FINAL REPORT

Social and Economic Impacts of 

Space Weather in the United 

States

September 2017

Abt Associates

Bethesda, Maryland

Written under contract for the 

NOAA National Weather Service
Abt Associates Inc.

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NOAA's National Weather Service

NOAA's National Weather Service is the US Government official and definitive source of civilian space weather 

watches, warnings, and alerts to the general public, industry, and government agencies. NOAA provides real-time 

monitoring and forecasting of solar and geophysical events, which impact satellites, power grids, communications, 

navigation, and other technological systems.
Table of Contents

1. Introduction 1

1.1 References 2

2. Approach 4

2.1. References 8

3. Electric Power 10

3.1 Impact Mechanisms 10

3.2 Stakeholder Perspective on Impacts 11

3.3 Cost Estimates 16

3.4. Power References 24

4. Satellites 26

4.1 Impact Mechanisms 26

4.2 Stakeholder Perspectives on Impacts 27

4.3 Cost Estimates 32

4.4 Satellite References 37

5. Global Navigation Satellite Systems (GNSS) Users 39

5.1 Impact Mechanisms 39

5.2 Stakeholder Perspectives on Impacts 40

5.3 Cost Estimates 46

5.4 GNSS References 51

6. Aviation 53

6.1 Impact Mechanisms 53

6.2 Stakeholder Perspectives on Impacts 54

6.3 Cost Estimates 59

6.4 Aviation References 64

7. Key Findings and Conclusions 65

8. Recommended Next Steps 68

8.1 References 70
Acknowledgements

We would like to thank the individuals who contributed their time, knowledge, and expertise to this effort. In addition 

to anonymous contributors, these individuals included (listed in alphabetical order): Dan Baker, Paul Cripwell, Geoff 

Crowley, Mark Dickinson, Gary Edwards, Kevin Forbes, Joaquim Fortuny-Guasch, Trevor Gaunt, Greg Ginrich, Mark 

Gunzelman, Ewan Haggarty, Tom Helms, Frank Koza, Elisabeth Krausmann, Justin Likar, Jeffrey J. Love, Yahya 

Memarzadeh, Pat Murphy, Paul O’Brien, Dr. Sten Odenwald, Antti Pulkkinen, Graham Rennie, Klaus Sievers, Mike 

Steckelberg, Mike Stills, and Hans Visser. 
1

1. Introduction

Space weather broadly refers to time-variable conditions in the near-Earth space environment including the sun, 

solar wind, magnetosphere, ionosphere, and thermosphere. It represents a natural hazard that is known to interrupt and 

damage technologies critical to modern society such as electric power grids, airlines, trains, pipelines, and Global 

Navigation Satellite Systems (GNSS) [National Research Council, 2008; Baker and Lanzerotti, 2016]. Despite such 

risks and our growing dependencies on these technologies for almost all aspects of daily life, there have been a limited 

number of studies on space weather’s social and economic impacts [National Research Council, 2008; Eastwood et al.,

2017]. In order to address this significant knowledge gap, this report represents a first attempt to systematically identify, 

describe, and quantify the impacts of space weather events within the United States (U.S.). Since better understanding 

these impacts is essential for enhancing our preparedness and strategically reducing our risks, this report also establishes 

the comprehensive foundation and analytical framework necessary for stimulating timely discussions and advancing this 

frontier. We furthermore hope our initial study helps enable the proliferation of careful research that is necessary for 

addressing the impacts of space weather with the same rigor and attention paid to other natural hazards where our 

collective understanding is comparatively more mature (e.g. hurricanes, tornadoes, tsunamis, wildfires, droughts). 

It is now well recognized that space weather presents significant risks to the U.S. economy and to the safety of 

its citizens. Space weather has been identified by the federal government as one of the grand challenges for disaster risk 

reduction [National Science and Technology, 2015], and most recently, it has been addressed in a National Space 

Weather Strategy [Executive Office of the President, 2015a] and National Space Weather Action Plan (SWAP) 

[Executive Office of the President, 2015b]. Our study was in part initiated in response to the SWAP (see Action Item 

4.5.2), a much larger U.S. effort for addressing potential vulnerabilities and increasing resilience by setting detailed 

national goals and promoting enhanced coordination and cooperation across public and private sectors [Executive Office 

of the President, 2015b]. Furthermore, NOAA recognizes that underlying the national effort to enhance the preparedness 

for space weather events is the need to improve our understanding of the social and economic impacts. NOAA also 

understands that there is a recurring need for this type of analysis and supports the full documentation of methods, 

procedures, data sources, and lessons learned to encourage the consistency of future efforts. Although the growing 

national and international recognition of this important topic has led to a handful of other socioeconomic impact studies 

that were recently finished or are concurrently underway in Europe, we were unable to draw upon such efforts for this 

study since they differ somewhat in scope [e.g. Oughton, 2017], are not yet published [e.g. Biffis and Burnett, 2017], or 

are publically unavailable [e.g. Luntama et al., 2017]. 

One of our study goals was to capture and synthesize what is known about space weather impacts across four 

technological sectors of prime concern: electric power, satellites, GNSS users, and aviation. Another goal involved 

translating our findings into quantitative estimates monetizing the potential impacts associated with different sized space 

weather storms including both a “moderate” and more “extreme” event. Analyzing two different sized events is an 

essential first step towards better understanding how impacts may change as storm size escalates. Examining “moderate” 

events that are lower in intensity but occur more frequently helps establish key thresholds above which notable impacts 

are expected based on empirical insights from sector and stakeholder experiences, including past-events where impacts 

were observed and impact thresholds were therefore exceeded (e.g. the March 1989 event [Allen, 1989] and the 2003 

Halloween Storm [Lopez et al., 2004]. Since impact thresholds may increase or decrease alongside changes in 
2

technologies, policies, and societal processes, studying the impacts of “moderate” events is also essential for anticipating 

how impacts may change in the future. The impacts of “moderate” events may also seem small when considered in 

isolation and/or when compared to more “extreme” event scenarios. However, since they occur more frequently, they 

may nonetheless add up and be significant over time. Considering more “extreme” events that are higher in intensity 

but occur less frequently is important for exploring more devastating and costly scenarios. To analyze a more “extreme” 

event, we considered both scientific and engineering expertise within each technological sector and different working 

definitions for “extreme” events such as the 1-in-100 year storm parameters set by the U.S. SWAP Phase I Benchmarks 

[Executive Office of the President, 2017] and “reasonable worst-case events” established by efforts in the United 

Kingdom (UK) [Cannon et al., 2013; Hapgood et al., 2016]. It is important to note that our “extreme” estimates do not 

necessarily reflect a Carrington-like event or the theoretical maximum level event. This topic was beyond the scope of 

our project since there is no scientific consensus on how large the Carrington event was or how big of an event is even 

possible. It is also important to note that there are inconsistencies (e.g. different event durations) with our space weather 

event scenarios for moderate and extreme events between sectors. This results from our approach that considers impacts 

on a sector by sector basis and captures stakeholder perspectives from different industries. Such inconsistences are not 

necessarily problematic but they should be further scrutinized and resolved with future efforts. Although we anticipate 

strong interest in our cost estimates, we emphasize that our numbers represent first pass estimates that should not be 

taken out of context or quoted without the appropriate caveats since they need to be critically reviewed and refined with 

future efforts. We therefore urge the reader to consider the qualitative information that we synthesize and the quantitative

framework that we establish to be equally informative and perhaps the more substantive contribution of our effort.

The following sections include an overview of the study methodology and framework (Chapter 2) followed by 

the findings for the four technology sectors (Chapters 3 – 6). Specifically, the sector chapters are organized into impact 

mechanisms, stakeholder perspectives, and cost estimates. Each sector chapter begins with the impact mechanisms, 

which outlines the major causal pathways from solar events to physical effects and then to societal impacts. The 

stakeholder perspectives provide an overview of our outreach findings and also more detailed notes. The cost estimates 

provide a tractable description of our quantification approach, including how we used key insights and assumptions from 

additional stakeholder outreach to build these estimates for both moderate and more extreme storm scenarios. Finally, 

Chapters 7 and 8 provide a summary of key findings and recommended next steps.

1.1 References 

Allen, J., H. Sauer, L. Frank, P. Reiff. 1989. Effects of the March 1989 Solar Activity. Eos, Vol. 70, No. 46.

The cost estimates provided in this report represent a first pass, and should not be taken out of 

context or quoted without appropriate caveats since they need to be critically reviewed and 

refined with future efforts. Readers are urged to consider the qualitative information 

synthesized from stakeholder outreach and peer reviewed sources and the quantitative 

framework established from this information as the more important contribution of this effort. 
3

Baker, D. N. (2009), What Does Space Weather Cost Modern Societies?, Space Weather, 7, S02003, 

doi:10.1029/2009SW000465.

Baker, D.N. and L.J. Lanzerotti. 2016. Resource Letter SW1: Space Weather. American Journal of Physics. Vol. 

84, No. 3.

Biffis, E. and C. Burnett. 2017. Report on the UKSA-funded IPSP SWx/SWe socio-economic study. Report on the 

ESA Space-Weather Socio-Economic Study L5 in Tandem with L1: Future Space-Weather Missions 

Workshop. March 6-9, 2017

Cannon, P.; Angling, M., Barclay, L., Curry, C., Dyer, C., Edwards, R., et al., 2013. Extreme space weather: impacts 

on engineered systems and infrastructure, UK Royal Academy of Engineering, London, ISBN 1-903496-95-0.

Eastwood, J.P., E. Biffis, M.A. Hapgood, L. Green, M.M. Bisi, R.D. Bently, R. Wicks, L.A. McKinnel, M. Gibbs, and 

C. Burnett. 2017. The Economic Impact of Space Weather: Where Do We Stand? Rick Analysis, Vol. 37, 

No. 2

Executive Office of the President, 2015a, National Space Weather Strategy. 

Executive Office of the President, 2015b, National Space Weather Action Plan. Product of the National Science And 

Technology Council. 

Executive Office of the President, 2017. Space Weather Phase I Benchmarks. Product of the Space Weather 

Operations, Research, and Mitigation Committee of The National Science and Technology Council. 

Hapgood, M., Angling, M., Attrill, G., Burnett, C., Cannon, P., Gibbs, M., et al., 2016. Summary of space weather 

worst-case environments. Revised edition. RAL Technical Report RAL-TR-2016-06. 

National Research Council. 2008 Severe Space Weather Events – Understanding Societal and Economic Impacts: A 

Workshop Report. National Academies Press. 

Lopez, R.E., D.N. Baker, and J.H. Allen. 2004. Sun unleashes Halloween Storm, Eos, Vol. 85, No. 11

Luntama, J.P, N. Bobrinsky, and S. Kfraft. 2017. Report on the ESA Space-Weather Socio-Economic Study L5 in 

Tandem with L1: Future Space-Weather Missions Workshop. March 6-9, 2017

Oughton, E. 2017. Report on the Cambridge SWx/SWe Socio-Economic Study, Report on the ESA Space-Weather 

Socio-Economic Study L5 in Tandem with L1: Future Space-Weather Missions Workshop. March 6-9, 2017
4

2. Approach

This study began with an extensive literature review; however, similar to a 

concurrent and recently published study, we also found a limited number of previous 

studies on the social and economic impacts of space weather [Eastwood et al., 2017]. 

We also quickly recognized that this topic represented a formidable research problem at 

the intersection of science, engineering, economics, and the social sciences [Baker,

2009]. For example, modern society’s fortunate lack of direct experience of “extreme” 

events, and either limited or rather largely undocumented/unshared experiences of 

“moderate” events, pose a number of theoretical and analytical challenges that require 

many assumptions, simplifications, extrapolations, and inferences. In addition, there is 

no standard definition nor scientific agreement on what constitutes either an “extreme” [e.g. Executive Office of the 

President, 2017] or “moderate” event, and when studying impacts, will furthermore be dependent on and relative to the 

specific technology and impact pathway of interest [e.g. Cannon et al., 2013; Hapgood et al., 2016]. The response of 

various technologies (e.g. power grid, satellites, airplanes, GNSS) to “extreme” events is furthermore largely unknown 

since they fall beyond engineering standards and operational experiences. Although the response of different 

technologies to “moderate” events may be relatively better understood, such information is often not readily available 

since publically disclosing potential vulnerabilities can be devastating for businesses. Moreover, impacts are not simply 

directly proportional to event sizes but are also affected by a number of other important factors like geography, the time 

of day, or season of the year which, for example, affect the demand on the electric power grid [e.g. Forbes and St. Cyr,

2012]. Further complications arise from economic and social processes that are complex, interconnected, and rapidly 

evolving. These early study findings therefore shaped our approach, in which we aimed to develop a comprehensive 

and coherent framework in order to help this become a more tractable research problem that others across industries, 

institutions, and disciplines can build off and contribute their knowledge and expertise to. 

Our review of existing information included findings of peer-reviewed literature, government reports, industry 

organizations, and other publically available documents. Given the lack of previous impact studies, we focused our 

efforts on dissecting the far more extensive scientific and engineering literature addressing the physical effects of space 

weather across our four focal sectors (electric power, satellites, GNSS users, and aviation) [see Baker and Lanzerotti, 

2016 for a recent and comprehensive overview]. Although effects and impacts are often used interchangeably, here we 

consider physical effects to be fundamentally different than impacts in the sense that the former represents effects on 

systems or system performance caused by natural phenomenon and processes. Effects are what, if not appropriately 

addressed by design and engineering decisions or managed with operator actions, will ultimately cause impacts (in the 

case of space weather, negative consequences) and therefore represent different potential impact mechanisms and 

pathways. Focusing on physical effects furthermore helped us establish a technically sound link between space weather 

events and their downstream social and economic impacts on a sector by sector basis. Although not widely studied, we 

found that the impacts of space weather are somewhat well documented in historic accounts of notable space weather 

events [Allen et al., 1989; Lopez et al., 2004] and also often highlighted in technical work as a research motivation. To 

synthesize our findings for each sector, we established a discrete list that included 17 known physical effects across the 

four sectors (Table 1). We also constructed impact mechanism diagrams for each sector that outline the major causal 

The impact of 

space weather is a 

formidable 

research problem 

at the intersection 

of science, 

engineering,

economics, and the 

social sciences.
5

pathways from solar events to physical effects and then impacts. These diagrams represent a first attempt to help simplify 

many of the complexities surrounding this interdisciplinary problem, allowing for a clear illustration of key processes 

and relationships. They should be refined and vetted with additional input from stakeholders and experts. 

Table 1. The physical effects of space weather on different technological sectors, as identified and defined in the 

report, include a range of natural processes and phenomenon that are relatively well studied by scientists and 

engineers. If these physical effects (defined and discussed throughout the remainder of report) are not appropriately 

addressed by design and engineering decisions or managed with operator actions, they will ultimately cause impacts 

(“negative consequences”) and therefore represent different potential impact mechanisms and pathways. Impacts 

caused by these effects can furthermore be organized into different impact categories (see Figure 1 and Table 2).

Technological Sector 

Electric Power Satellites GNSS Users Aviation

● Reactive Power Consumption

● Transformer Heating

● Improper Operation of 

Protective Relaying Equipment

● Real Power Imbalances 

● Generator Tripping

● Loss of Precision Timing

● Loss of Altitude

● Link Disruptions

● Anomalies

● Cumulative Dosage

● Ranging Errors

● Loss of Lock 

● Communication 

Degradation

● Navigation 

Degradation

● Avionic Upsets

● Effective Dose

After noting a wide range of socioeconomic impacts from the literature, we organized our analysis by creating 

five broad but interrelated impact categories (see Figure 1 and Table 2 for more details). Our first category, Defensive 

Investments, captures expenditures that help protect technologies against potential vulnerabilities such as on engineering 

designs or on situational awareness. Mitigating Actions covers real-time decisions made by system operators to reduce 

the consequences of an event that is anticipated or underway. Asset Damages refers to any physical damage to sector 

equipment that may result either suddenly (“acute”) or slowly over time (“chronic”). Service Interruptions addresses 

impacts seen by end users of technologies such as changes in provision, quality, and/or pricing. The final impact category 

is Health Effects, which covers any direct potential hazard to human well-being or life such as from elevated radiation. 

Focusing on direct health effects from events in this last category does not include any of the health effects that would 

result indirectly via our other impact categories (e.g. health effects from an extended power outage would be captured 

under Service Interruptions). In addition to showing how these different categories relate to one another, Figure 1 also 

shows the different types of space weather products and services, such as those provided by NOAA’s Space Weather 

Prediction Center (SWPC), that can add value to society by lessening these impacts. Note that the first two of these 

impact categories capture proactive approaches to managing space weather impacts whereas the last three capture the 

impacts that could be realized in the advent that such proactive strategies are insufficient for absorbing the full magnitude 

of the event. Although a rigorous consideration of how the impacts categories are interrelated is beyond the scope of 

this current body of work, it is important to note that there are costs associated with all of these impact categories and 

this is apt to represent an optimization problem in which one must consider the costs, benefits, and trade-offs associated 

with each. 
6

Figure 1. The range of potential economic and societal impacts of space weather to different technological sectors can 

be organized into five different but interrelated categories (red boxes). A range of space weather products and services, 

such as those offered by NOAA’s SWPC (blue boxes), are valuable at different points in time and have the potential 

to reduce specific types of impacts. 

We then conducted an initial round of stakeholder outreach to better understand these physical effects and the 

different categories of impacts associated with each. Although we use the word stakeholder generally to describe any 

individual with relevant knowledge from industry, government, or academics, our outreach was aimed most directly at 

engineers and operators working within our different focal sectors. We used a Delphi-like approach [Helmer, 1967] to 

solicit feedback on our literature review findings (e.g. physical effects and example impacts organized by impact 

category) from more than 30 stakeholders of diverse expertise. To facilitate these conversations, we constructed a simple 

matrix for each sector that connected our identified physical effects to our five different impact categories (for additional 

details, see sections on Stakeholder Perspective on Impacts within different chapters of this report). These matrices were 

initially populated with specific examples culled from the literature, shown to stakeholders for reactions and thoughts, 

and then expanded or revised based on information they provided. An updated matrix was iteratively shown to 

subsequent stakeholders so the next stakeholder could offer critical input on our current understanding and fill in any 

remaining gaps. We iterated this process until further input yielded few substantive changes but also took advantage of 

any additional opportunities to further discuss our matrices with other stakeholders even after they had solidified. 

Iterating this process allowed us to: (1) refine our list and descriptions of the physical effects; (2) gauge the relative 

frequency and severity of their occurrence, including information on impact thresholds; (3) identify likely future trends 

due to changing technologies, policies, and/or economics; (4) recognize consensus or disagreement between 

stakeholders; (5) contextualize space weather with other sector hazards; (6) gain insights on how the impacts may change 

as storm size escalates from “moderate” to “extreme”; and (7) understand how current applications of space weather 

information reduce sector vulnerabilities. We took detailed notes on each conversation but given that this can be a 

sensitive and largely private subject within various industries, our notes are organized and reported generally in tables 

and throughout this document without attribution to particular individuals. 
7

Table 2. Definitions of the five impact categories created to organize the vast number and wide range of potential social 

and economic impacts that could potentially result from space weather events across different technological sectors. 

Descriptions also address how the different categories may relate to one another and where space weather products and 

services, such as those provided by NOAA’s Space Weather Prediction Center, can add value by lessening these impacts. 

These impacts are presented in chronological order in relationship to a particular space weather event (see Figure 1 for 

additional information). 

Impact 

Category Definition

Defensive 

Investments

This impact category captures expenditures made in advance of any particular space weather event that help protect 

technological systems against potential impacts of an event. In general, such investments tend to be capital 

intensive and are therefore financially justifiable if they help make systems more robust to “all-hazards” as well 

(e.g. severe weather, earthquakes, floods, terrorism, etc.). Examples include the devotion of resources to 

engineering at both the component and system level, to enhancing real-time situational awareness, and to 

developing plans and operational procedures for different space weather scenarios. Space weather products and 

services, such as those provided by NOAA’s Space Weather Prediction Center (SWPC) add value to different 

sectors by providing scientific information necessary to properly understand their risks and vulnerabilities. 

Mitigating 

Actions

This refers to the undertaking of a specific action or suite of actions in preparation for an anticipated space weather 

event or in response to one that is underway in order to reduce or limit potential impacts. The ability to mitigate 

requires timely and accurate information about the space weather environment and operators must further be able 

to understand and act upon it. The mitigating actions enacted by operators involve different levels of 

resources/costs and may or may not impact the services they provide. Space weather products and services add 

value to different sectors by providing a range of information about the space weather environment that offer 

different lead times (e.g. forecasts, warnings, alerts, now casts) for different types of events (e.g. geomagnetic 

storms, radiation storms, and radio blackouts). 

Asset 

Damages

This impact category refers to any degree of physical damage to sector assets that may result from space weather 

either suddenly (“acute”) or slowly over time (“chronic”). Examples of acute damage include partial or complete 

destruction of an asset that may cause it to become temporarily or permanently inoperable. Acute damage may in 

turn lead to Service Interruptions if it is widespread or if it occurs to assets that are unique or else critically located. 

Chronic damage represents additional wear and tear on assets that accelerate their aging and reduce their lifespan. 

Chronic damage represents operational or maintenance costs to a sector as parts then have to be fixed or replaced 

more frequently. Space weather products and services, such as those provided by NOAA’s SWPC add value to 

different sectors by providing the scientific information necessary to conduct post-event analysis. Better 

understanding what caused a specific incident of asset damage can feed into various Defensive Investments (e.g. 

design and engineering or situational awareness) that help reduce future losses. Asset Damages caused to any 

downstream industry, due to Service Interruptions of the directly impacted sector, would be covered in the 

following category. 

Service 

Interruptions

This category captures the range of potential impacts seen by the end users of the services provided by a sector 

such as adverse changes in the quality, price, or provision. In general, Service Interruptions have direct economic 

consequences to service providers within each sector either by harming their reputation or due to losses in revenue 

during service outages. There are also economic and societal impacts on end users that vary depending on how 

the disturbance propagates and trickles through different businesses. It is through Service Interruptions that the 

sectors studied in this report are coupled to each other and to wider society. SWPC products and services add

value to different sectors by allowing service providers within different sectors to better communicate with their 

clients about the potential and probability for Service Interruptions so they can be informed of potential threats to 

their businesses and have more options available to them. Also, there can be indirect impacts to upstream and 

downstream businesses due to Service Interruptions with the directly impacted sector. 

Health 

Effects

This addresses direct health hazards such as radiation exposure and therefore is most applicable to humans flying 

at airplane altitudes at the time of a space weather event. Astronauts in space during severe space weather are also 

at great risk. The medical research linking aviation related exposure and adverse human health risks is tenuous but 

if established would imply economic impacts such as direct treatment costs (e.g., hospital bills), the costs of pain 

and suffering, the costs of lost life-years, and lost earnings. Space weather products and services, such as those 

provided by NOAA’s SWPC add value through the provision of scientific information that can be used to study 

and explore these potential linkages and by providing information about potential exposure environment so 

airlines, aircrew, and astronauts can be precautionary and track their total exposure or take actions to reduce their 

exposure. 

This initial round of stakeholder outreach allowed us to gather key insights and information that we then used 
8

to begin developing cost estimates for both our “moderate” and more “extreme” event scenarios. However, to ensure 

that we correctly understood and carefully interpreted these conversations and the various highly technical issues 

embedded within this topic, we continued to interact with these stakeholders intermittently and more informally as we 

proceeded with our research (e.g. quick emails, impromptu calls, in person meetings). This additional outreach helped 

us better understand the (1) key physical effects of concern for each sector, (2) most relevant impact category(s) and 

plausible impacts, (3) assumptions, nuances, and caveats surrounding these effects and their potential impacts, and (4) 

available information and data. Since estimating the total costs associated with both a “moderate” and more “extreme” 

event would involve considering impacts stemming from our 17 different physical effects across four sectors and all five 

social and economic impact categories, we needed to establish priorities for our quantitative effort. We decided to 

develop cost estimates most reflective of stakeholder concerns and for the impact categories that were also apt to reflect 

the largest potential impacts. Where possible (all sectors except GNSS users), we also tried to establish cost estimates 

for one of our proactive impact categories (either defensive investments or mitigation actions) and also one for our 

realized impact categories (asset damages, service interruptions, or health effects). Although tangential to our main 

study goals, we found it interesting and insightful to consider the different potential costs associated with these different 

approaches to managing space weather impacts. 

Stakeholders were very vocal about the challenges associated with trying to develop potential cost estimates 

and cautioned us about the many complexities and large uncertainties involved. Although we began our effort wanting 

to model the impacts of space weather, we simply could not justify such an approach since the stakeholders we spoke to 

emphasized how it is intractable at this point in time to rigorously connect the magnitude of a space weather event to our 

list of physical effects and ultimately to the types and sizes of the impacts that may result. Recognizing the importance 

and need to develop a better quantitative understanding of this topic, many of our stakeholders expressed their 

willingness to help guide our effort as their availability allowed (which in quite a few instances involved weekend emails 

and phone calls). In their opinion, it was essential to capture and codify certain industry realities and nuances that are 

essential to this problem. We therefore opted to formulate cost estimates that capture and translate stakeholder insights 

on key aspects of this research problem into logical and quantitative statements. This involved, for example, initial 

discussions about what is reasonable to expect under “moderate” compared to more “extreme” space weather conditions. 

After further researching and considering such input, we put together initial equations with numbers and then shared 

them with our stakeholders. In addition to receiving feedback, this allowed us to obtain additional stakeholder insights 

including their gut reactions to assumptions we made and their best guesses to help constrain key variables even if they 

could only provide order of magnitudes or rough ranges. Our approach allowed us to establish a robust and novel 

understanding for what needs to be known in order to quantify space weather impacts and where the outstanding 

knowledge gaps lay. Proposing transparent, tractable cost estimates that are easy to follow and reproduce is additionally 

advantageous as it will allow others to readily critique, question, and improve our initial effort. It also provides 

flexibility, enabling our cost estimates to be updated as technologies and our societies evolve and additional knowledge 

is acquired. To clearly emphasize the large uncertainties surrounding the cost estimates presented herein, many of which 

were derived using placeholder numbers and all of which should be critically and widely reviewed, we provide lower 

and upper range estimates and also round all final estimates to one significant figure. 

2.1. References
9

Allen, J., H. Sauer, L. Frank, P. Reiff. 1989. Effects of the March 1989 Solar Activity. Eos, Vol. 70, No. 46.

Baker, D. N. (2009), What Does Space Weather Cost Modern Societies?, Space Weather, 7, S02003, 

doi:10.1029/2009SW000465.

Baker, D.N. and L.J. Lanzerotti. 2016. Resource Letter SW1: Space Weather. American Journal of Physics. Vol. 

84, No. 3.

Cannon, P.; Angling, M., Barclay, L., Curry, C., Dyer, C., Edwards, R., et al., 2013. Extreme space weather: impacts 

on engineered systems and infrastructure, UK Royal Academy of Engineering, London, ISBN 1-903496-95-0.

Eastwood, J.P., E. Biffis, M.A. Hapgood, L. Green, M.M. Bisi, R.D. Bently, R. Wicks, L.A. McKinnel, M. Gibbs, and 

C. Burnett. 2017. The Economic Impact of Space Weather: Where Do We Stand? Rick Analysis, Vol. 37, 

No. 2

Forbes, K. F., and O. C. St. Cyr (2012), Did geomagnetic activity challenge electric power reliability during solar cycle 

23? Evidence from the PJM regional transmission organization in North America, Space Weather, 10, 

S05001, doi:10.1029/2011SW000752.

Executive Office of the President, 2017. Space Weather Phase I Benchmarks. Product of the Space Weather 

Operations, Research, and Mitigation Committee of The National Science and Technology Council. 

Hapgood, M., Angling, M., Attrill, G., Burnett, C., Cannon, P., Gibbs, M., et al., 2016. Summary of space weather 

worst-case environments. Revised edition. RAL Technical Report RAL-TR-2016-06. 

Helmer, O. 1967. Analysis of the Future: The Delphi Method. The RAND Corporation, Santa Monica, California. 

Lopez, R.E., D.N. Baker, and J.H. Allen. 2004. Sun unleashes Halloween Storm, Eos, Vol. 85, No. 11
10

3. Electric Power

3.1 Impact Mechanisms

A space weather event can produce Geomagnetically Induced Currents (GICs) that may be transmitted by 

effective conductors on the Earth’s surface such as the electric-power grid. When GICs enter the power grid, they act 

as direct current (DC) sources that flow alongside the normal alternating currents (AC) produced at power plants and 

transferred along power lines to electrical substations. Basic incompatibilities between DC and AC currents may 

interfere with the normal functioning and performance of Extra High Voltage (EHV) transformers. The interaction of 

GICs with these transformers can result in a number of physical effects that, if sufficiently large and not properly 

managed, may adversely impact the power system [Cannon et al., 2013; Pulkkinen et al., 2017]. For example, GICtransformer interactions can increase reactive power consumption [Tay and Swift, 1985; Price, 2002], contributing to 

voltage instabilities and potentially leading to power outages. They can also generate harmonics that can disconnect 

parts of the grid by causing the improper operation of protective relay equipment (e.g. static compensators) [e.g. 

Bolduc, 2002; Pulkkinen et al., 2005] and/or the tripping offline of generators [e.g. Rezaei-Zare and Marti, 2013]. It 

is important to note that this impact pathway is the only one that has to-date been known to trigger space weather-related 

blackouts. Specifically, it was the underlying cause of the 1989 Hydro-Québec outage [Bolduc, 2002] and the Swedish 

outage during the 2003 Halloween storm [Pulkkinen et al., 2005]. GIC-related degradations in transformer performance 

may also challenge electric power reliability as suggested by statistically significant empirical correlations between real 

power imbalances and GIC data [Forbes and St. Cyr, 2010; 2012]. And lastly, GIC-transformer interactions can cause 

transformer heating and if sustained over a sufficient period of time (e.g. tens of minutes ) may become problematic 

(e.g. hot-spot heating). This physical effect can in turn lead to various degrees of transformer damage from incremental 

degradation of transformer components [Tay and Swift, 1985; Gaunt and Coetzee, 2007] to more severe physical damage, 

such as the melting of copper windings, that may require repairs or removal from service [e.g. Kappenman, 2010]. Space 

weather impacts on GNSS users, covered in a later chapter of this report, may also be consequential to the power grid. 

GNSS/GPS precision timing enables key components of the grid to be synchronized (e.g. generation, transmission, and 

distribution) and if interrupted during a space weather event, may become problematic.
11

Figure 2. Impact mechanism diagram for electric power outlining the primary causal pathways from a solar event to 

physical effects (grey boxes) that can in turn cause a variety of social and economic impacts (green boxes). Note that 

our illustration depicted is not to scale, not comprehensive, and should be revised with future input from stakeholders 

to ensure it captures largest potential concerns. 

3.2 Stakeholder Perspective on Impacts

Our first phase of stakeholder outreach involved hour long phone calls with six individuals working within the 

power industry. As previously described (Approach), we used our power sector impact matrix to guide these 

conversations and to systematically collect stakeholder input on the various physical effects of space weather and the 

types of impacts caused by each. Our final impact matrix is presented below (Table 3) along with additional and 

important insights from these conversations, including definitions and notes on the various physical effects (Table 4) 

and impacts (Table 5). The text that follows provides a high-level overview of our most important findings. 

Of the various known physical effects of space weather on the power grid (Table 4), stakeholders all agreed 

that reactive power consumption is by far the most concerning. It is of particularly high concern because it represents a 

network threat that has the potential to, within less than one minute, lead to voltage collapse and system instability. 

Stakeholders noted that the U.S. power industry now widely and formally recognizes this threat, as evidenced by the 

National Energy Regulatory Commission (NERC) Emergency Preparedness and Operations (EOP) standard, EOP-010-

1, which became effective in April 2015. In order to enhance electric reliability, reliability coordinators and transmission 

operators report that they are now required by law to have contingency procedures for mitigating the effects of 

geomagnetic disturbances (GMD). Stakeholders report that these contingency procedures encompass a broad range of 

Mitigating Actions. They were able to offer some examples of what such procedure might entail (e.g. reducing 

transmission flows, redispatching generation, and/or reconfiguring network topology) but stressed that actual 
12

contingency procedure that might be enacted during any particular GMD event would vary from operator-to-operator 

and inevitably depend on many real-time power system details. It was further noted, however, that most if not all of the 

Mitigating Actions that might be enacted during a space weather event are routinely enacted for other non-space weather 

reasons (e.g. terrestrial weather) so their costs, while potentially significant on a per event basis, may be relatively small 

in the context of their annualized operational costs. 

Stakeholders noted that if such procedures are not enacted or are unable to boost reactive power to a sufficient 

level, far more costly wide-area blackouts could in theory result. Recovering the power system from such an occurrence 

might in turn take the industry ~6 to 9 hours, representing the time required to coordinate and synchronize the large 

number of individual system components. The industry stakeholders that we talked to also expressed less concern about 

transformer heating leading to damage (i.e. over-heating) which was the focus of early social and economic impact 

assessments. Although this impact pathway underpins such early scenarios envisioning catastrophic transformer damage

that causes prolonged power outages (e.g. months to years) [Kappenman, 2010], stakeholders noted that this physical 

effect is only worrisome if it is substantial and sustained. It is currently thought that reactive power consumption will 

quickly disconnect these transformers, cutting off the heating source that could potentially cause damage. In 2016, 

FERC mandated (TPL-007-1) that infrastructure owners conduct rigorous analyses in order to better understand how 

vulnerable our nation’s transformers may be to a severe, 1-in-100 years GMD benchmark event. Stakeholders report 

that these analyses will ultimately support decisions about what Defensive Investments (e.g. blocking capacitors, 

replacement transformers, etc.) the industry needs to make to increase reliability by hardening their infrastructure and 

assets against this benchmark event. They furthermore communicated that this mandate will likely impose one-time 

costs that are more substantial than the costs imposed by EOP-010-1. 
13

Table 3. Impact matrix populated during stakeholder outreach to better understand how the well-studied physical effects of space weather on electric power 

can cause different types of Social and Economic Impacts. Items in matrix reflect example impacts for moderate (normal text) and extreme (italic text) storms. 

Question marks denote instances where the physical effect may in theory be able to cause this impact but empirical support is lacking. *Additional details 

pertaining to a select set of these impacts can be found in Table 5. 

Physical Effects

Impact Categories

Defensive 

Investments

Mitigating

Actions

Asset

Damage

Service 

Interruptions

Health 

Effects

Reactive Power 

Consumption

•Infrastructure hardening*

•Situational awareness & 

Preparedness*

•Reduce transmission flows

•Redispatch generation

•Network reconfiguration

•Emergency procedures*

•Degradation in 

power quality*

•Price fluctuations

•Blackouts?

Transformer Heating

•Infrastructure hardening*

•Situational awareness & 

Preparedness*

•Spare transformers

•Reduce transmission flows

•Redispatch generation

•Network reconfiguration

•Emergency procedures*

•Transformer aging

•Partial damage

•Transformer Failure

•Price fluctuations

•Blackouts?

•Catastrophic grid 

failure

Improper Operation 

of Protective 

Relaying Equipment

•Infrastructure hardening*

•Situational awareness & 

Preparedness*

•Reduce transmission flows

•Redispatch generation

•Network reconfiguration

•Emergency procedures*

•Damaged equipment •Blackouts*

Real Power 

Imbalances

•Reduce transmission flows

•Redispatch generation

•Network reconfiguration

•Emergency procedures*

•Degradation in 

power quality

•Price fluctuations

•Blackouts?

Generator Tripping •Infrastructure hardening* •Protective relay settings •Loss of generation

Loss of Precision 

Timing

•Backup technologies
14

Table 4. Space weather can cause a variety of physical effects to the power grid. These physical effects, defined 

below, are relatively well-studied in the scientific and engineering literature. These physical effects were discussed 

with industry stakeholders in order to better understand their potential for causing different types of social and 

economic impacts. 

Physical 

Effects Definition Notes from Stakeholder Outreach

Reactive 

Power 

Consumption

Reduction in amount of 

reactive power flowing 

through grid due to the 

increased consumption of 

reactive power by 

transformers. 

• This is problematic because it depresses the system voltage and may lead to voltage 

collapse. It occurs at transformers but is a grid-scale threat. 

• Voltages are controlled within tight bands. When system gets to ~10-20% of normal 

voltage, this triggers a concern for blackouts. 

• Reactive power does not like to travel so highest vulnerability in areas farthest away 

from generation and highest loads. Managing reactive power issue may be most 

challenging in the spring and fall, where generation is modest but there are economic 

incentives for moving electricity long distances. 

• Increasing problem as we rely on higher voltage power lines (long distance 

transfers). Relying more heavily on local generation can help mitigate, but trend is 

for it to be shut down in favor of long distance transfers. Certain renewables (e.g. 

Solar), which tend to be local and more distributed, may be helpful for these reasons. 

Transformer 

Heating

Substantial heating of internal 

transformer components that 

can cause accelerated asset 

aging and perhaps even 

transformer damage. 

• Probability of damage depends on design, age, use history, etc. 

NERC’s recently approved threshold based on potential transformer heating is 75 

amps/phase. Transformers can take more than this but this is the trigger to pay 

attention. The relationship between heating and damage is transformer specific so 

FERC standard is conservative in order to cover potential differences across nation 

in transformer designs. 

• Certain stakeholders expressed dissatisfaction with early economic analyses and feel 

the potential for failure is overstated. Before failure occurs, it is likely that 

transformers will be disconnected. This negative feedback could cause a blackout 

that may also protect against catastrophic failures. Utility perspective on probability 

of transformer damage will be known when studies related to TPL-007-1 are 

complete, in ~2 to 4 years from now (2017). 

• Transformer overheating may have implications for real-power imbalances too. 

Improper 

Operation of 

Protective 

Relaying 

Equipment

Improper functioning of relay 

systems that are designed to 

protect grid by detecting 

electrical aberrations (e.g. 

faults, surges, over/under 

voltages) and then isolating 

the impacted area from the 

rest of the network. 

• Infrequently observed but it does happen and when it does, the cause is not clear. It 

will likely be attributed to space weather only if they know an event is expected or 

underway. 

• Older relays generally more susceptible to harmonics, modern relays less so. 

• Most often trip capacitors banks offline. This increases reactive power losses, 

depressing system voltage and introduces blackout threat. This is what triggered the 

1989 Quebec blackout and the outage in Sweden during the Halloween 2003 storm. 

Real Power 

Imbalances 

Difference in real-time supply 

and demand for power that 

must be managed by operators 

to maintain grid stability. 

• Caused by many things in addition to space weather such as hot weather, etc. 

• Industry is aware of statistical relationship but unclear about physical basis. 

Degradation in transformer performance may cause issue (via generation control 

errors and high voltage electricity flows) or may result due to operator actions. 

Generator 

Tripping

Space weather related 

harmonics can also send 

erroneous commands to 

generators, tripping them 

offline. 

• One stakeholder brought this to our attention, a more niche topic compared to other 

physical effects but is nonetheless an important additional issue. 

Loss of 

Precision 

Timing

Loss of satellite enabled 

technology that provides 

precise timing information 

that is used to improve grid 

synchronization. 

• When satellite signals are lost, substation clocks will continue to operate and remain 

accurate for several hours.

• Not clear how space weather threat compares to spoofing threat but addressing 

spoofing concerns makes grid less vulnerable to space weather interruptions. The 

spoofing threat has been well studied by the industry and they find the threat to be 

small. 

• This could become more problematic in the future if we over rely on these systems. 

• Dependence on precision timing may be bigger trend in U.S. power sector than 

abroad. Other countries are required to maintain traditional timing devices at 

substations. 
15

Table 5. Additional details on a select set of space weather impacts identified and organized in our impact matrix (Table 

3). 

Impact 

Category Examples Definition Notes from Stakeholder Outreach

Defensive 

Investments

Infrastructure 

hardening

A range of engineering and design 

modifications that reduce grid 

vulnerability such as installing GIC 

absorbing or blocking devices (e.g. 

neutral ground connections, series 

line capacitors) or replacing aging or 

vulnerable transformers.

 Understanding what to do requires many analyses. 

Installing a blocking device, for example, can reroute 

current in unexpected and devastating ways.

 This is the subject of the new FERC regulations. The 

types of investments that need to be made are 

understood but unclear how widely or where they will 

be required.

Situational 

Awareness & 

Preparedness

Utilizing a range of data and tools to 

stay aware of current and anticipated 

future conditions. Data and products 

can come from the government (e.g. 

NOAA’s Space Weather Prediction 

Center), GIC monitoring networks 

(e.g. magnetometers, internalinstruments within transformers) or 

transformer monitors and be fed into 

grid simulators and management 

systems. This information can then 

be used to inform what operational 

procedures should be enacted as 

various situations arise.

 This Defensive Investment is critical to being able to 

implement real-time Mitigating Actions.

 Operators have training to prevent key downstream 

impacts but they need to be made aware of the 

situation, day ahead space weather warnings are most 

important.

 Operators monitor space weather products and pay 

extra attention to own data when they receive alerts at 

the upper end of scales (K7 or greater).

 Diagnostic equipment is being installed on 

transformers in order to optimize maintenance cycle. 

Although not installed for space weather events per 

say, it will allow any transformer heating to be rapidly 

assessed.

Mitigating

Actions

Redispatch 

Generation

Deciding to utilize generators that 

will enhance grid stability rather 

than those that will maximize profits.

 Relatively low cost action. One stakeholder 

mentioned that one space weather event may cost 

~$1s million but redispatching costs them ~$100s 

million per year.

 This is a relatively easy action for operators and 

almost always impacts the price of electricity.

Emergency 

Procedures

A set of operating procedures that 

can be enacted in extreme cases and 

might include, for example, 

generator or equipment curtailment, 

voltage reductions, and load 

shedding as a last resort.

 Different grid operators have different sets of 

emergency procedures and different triggers for 

enacting them in place.

Asset 

Damages

Transformer 

Aging

Accelerated aging of transformer 

caused, for example, by degradation 

and gas generation within insulation 

materials.

 Logic of argument makes sense but the empirical data

is not significant enough for industry to believe that 

moderate events “add up” and, among all else, play a 

big role in transformer aging.

 Data currently being compiled by industry and 

academics is essential for better resolving this issue. 

Transformer

Failure

Any damage to a transformer that 

renders it permanently inoperable 

and cannot be repaired and so 

requires a replacement transformer.

 Probability and extent of damage requires long GIC 

durations and scale with duration of GIC.

 Most likely to happen to older transformer that are 

near the end of their lifetime.

Service 

Interruptions Blackouts Loss of power to electricity users. 

 Storms have to be particularly extreme for this to 

happen (K8 or K9). NOAA scales need refinement to 

better discriminate between large events.

 More permanent loss of service that would result if a 

large number or certain critical transformers 

permanently fail, but probability of this occurring is 

thought to be very low.

 Costs of outages depend on where and when an outage 

occurs, something that is almost impossible to know 

in advance of an event occur.
16

3.3 Cost Estimates 

In order to translate our findings into quantitative cost estimates that capture the most concerning and potentially 

largest impacts, we conducted a second round of stakeholder outreach. After discussing the various possibilities and 

better understanding some of the challenges inherent to quantifying many of the impacts we identified (Table 3), we 

ultimately decided to develop power sector cost estimates for (1) Defensive Investments (~$50 million to ~$1 billion) 

and (2) Service Interruptions (~$400 million to ~$10 billion for a moderate event and ~$1 billion to ~$20 billion for 

more extreme conditions respectively). Our cost estimate for Defensive Investments focuses on the potential financial 

impacts of hardening the grid to comply with NERC’s recently enacted, TPL-007-1 standard. Our cost estimate for 

Service Interruptions explores the potential impacts to the end users of electricity from potential power outages. Our 

quantification process involved an iterative series of discussions with particularly helpful and committed stakeholders, 

combined with quantitative analyses based on the Value of Lost Load [London Economic International LLC, 2013]. Key 

insights gleaned from these conversations are provided below alongside a description of how they influenced the 

derivation of our cost estimates. 

Table 6. Simplified impact matrix with the focus of our quantitative analysis highlighted in yellow. The presence 

(or absence) of a circle denotes where we were able to connect a given physical effect to a particular impact category 

based on outreach (see Table 3 to better understand items these circles represent). Black circles denote that a physical 

effect is known, from direct past experience, to cause a particular category of societal impact. Open circles indicate 

that a given physical effect may cause a particular category of societal impact but lacks empirical support.

Physical Effects

Impact Categories

Defensive 

Investments

Mitigating 

Actions

Asset 

Damages

Service 

Interruptions

Health

Effects

Reactive Power 

Consumption ● ● ○

Transformer Heating ● ● ● ○

Improper Operation of 

Protective Relaying 

Equipment

● ● ● ●

Real Power Imbalances ● ○

Generator Tripping ● ●

Loss of Precision Timing ● ○

3.3.1 Defensive Investments 

We estimate that the one-time cost of hardening the U.S. power grid against potential space weather impacts 

may be ~$50 million to ~$1 billion. This estimate focuses on NERC’s recently approved TPL-007-1 standard requiring 

that our national power infrastructure be capable of withstanding a benchmark GMD event. In order to achieve this goal, 

TPL-007-1 (approved by FERC on September 22, 2016) requires infrastructure owners to analyze and then address the 

vulnerabilities of their system to NERC’s established benchmark. Stakeholders report that these analyses are just 

beginning and it will be ~2 to 4 years until they have their results. Although they already understand the available design 

and engineering options for addressing potential issues such analyses uncover, they do not yet know where or how 

extensively they will need to implement such measures. Our cost estimate presented below therefore aims to incorporate 

present industry perspectives on this topic and should be revisited as more information is acquired. 
17

We base our estimate on (1) the type and number of industry assets that may be vulnerable to NERC’s 

benchmark event and therefore may require hardening and (2) lower and upper boundaries on potential asset hardening 

costs. Although many specifics are lacking, such as where or how extensively hardening measures will need to be 

implemented, it is Extra-High Voltage (EHV) (e.g. 765-345 kV) transformers that are currently of the largest concern. 

Stakeholders note, however, that assets with voltages down to 220 kV are also undergoing assessment. In addition to 

well-established and studied vulnerabilities of these assets to space weather events, EHV transformers range in price 

from ~$4.5 million to ~$7.5 million (NERC, 2011) and therefore also represent one of the most expensive infrastructural 

components. At this point in time, stakeholders therefore think that EHV transformers will constitute the majority of all 

TPL-007-1 related hardening costs (as opposed to Corrective Action Plans (CAPs) that address operational procedures 

or Mitigating Actions). Although stakeholders were able to point us to various documents containing general information 

about the U.S.’s fleet of ~2,000 EHV transformers [DOE, 2014], they were quite hesitant to even venture a guess as to 

how many of these transformers might be vulnerable. They emphasized the complexity of the issue and why providing 

even rough numbers is hard in advance of them finishing their rigorous analysis. Specifically, vulnerability depends on 

many factors including transformer design, location, age, use history, network typology, and current system load. Most 

stakeholders further shared a similar hunch that the recently started studies will ultimately find a small number of 

vulnerable assets. A few were willing to go out on a limb and speculate that maybe ~1 to 10% of the total U.S. fleet, 

equating to ~20 to 200 EHV transformers, might be found vulnerable to NERC’s benchmark event. Although we were 

unable to find readily available data on many of the important variables to further explore what stakeholders already 

know about variations in vulnerability (e.g. vulnerability may be largest in transformers near the system edges or nearing 

the end of their operational lifetimes), stakeholders were able to offer some rough numbers on transformer design: ~85% 

(or 1700) of all EHV transformer might be single-phase transformers with the remaining ~15% (or 300) being threephase transformers. Noting that single-phase transformers are in general more vulnerable than three-phase transformers, 

we assign the lower portion of the potential vulnerability range (~1 to 10% of the total U.S. fleet) to more robust, threephase transformers (~1 to 5%) and the higher range to more susceptible, single-phase transformers (~6 to 10%). This 

suggests that in total, ~102 to ~170 single-phase and ~3 to ~15 three-phase EHV transformers may require hardening in 

order to meet NERC’s TPL-007-1 standard (Table 7). 

The second part of our estimate considers the wide range of costs that could be associated with hardening these 

potentially vulnerable transformers. Stakeholders inform us that the least expensive option is usually to install GIC 

blocking devices which can cost at least ~$500,000 per EHV transformer. If this engineering measure is implemented 

at all vulnerable transformers, total costs would be ~$50 million to ~$100 million (Table 7). Although relatively 

inexpensive, stakeholders also noted that blocking devices may not be a universal solution in all locations since their 

installation typically pushes the GIC, and therefore the problem, elsewhere in the network. Moreover, they are generally 

disliked across industry because they add complexity to the system that requires additional management and 

maintenance. Stakeholders also discussed that the most expensive option is to replace vulnerable transformers but noted 

that such replacements would be warranted because of many additional, non-space weather reasons such as because they 

are near or have exceeded their design lifetime. If all vulnerable transformers are replaced though, costs to the industry 

would instead total ~$500 million to ~$1 billion (Table 7). These low and high end-member possibilities suggest a final 

cost estimate for Defensive Investments of ~$50 million and ~$1 billion. We emphasize that this is a rough estimate 
18

that is intended to be illustrative yet informative and should be revisited periodically as TPL-007-1 studies progress. 

Table 7. Potential cost estimate of NERC TPL-007-1 standard to harden the U.S. Extra High Voltage (EHV) 

transmission system against space weather. 

Transformer 

Type1

F.O.B 

Price1

Installed 

Cost2

Total 

Number 

in U.S.3

Number (%) that 

may require 

hardening4

Cost Estimate

Lowest Cost 

Option (Blocking)

High Cost Option

(Replacement)

Single-Phase ~$4.5 m ~$5.7 m ~1700 ~102-170

(6 to 10%) ~$50-90 m ~$0.5-1 b

Three-Phase ~$7.5 m ~$9.6 m ~300 ~3-15

(1 to 5%) ~$2-8 m ~$30-100 m

Total ~2000 ~105-185 ~$50-100 m ~$0.5-1 b

1

Information directly from p. 3 (Table 1) in NERC, 2011 

2Derived from NERC, 2011 which notes that taxes, transportation, installation, testing, and other associated 

expenses which generally add an additional ~25 to 30% to F.O.B. (“Factory on Board”) price. We therefore 

calculate the installed cost by multiplying F.O.B. prices by 1.275. 

3The U.S. transmission system has ~2,000 EHV transformers (DOE, 2014). Estimates for the number of singleand three-phase transformers was derived based on stakeholder input that they might ~15% and ~85% of entire 

U.S. fleet respectively. 

4Based on stakeholder input.

5Low cost option assumes that the system will be hardened by installing a blocking device (~$500,000 per 

transformer) at every vulnerable transformer. 

6High cost option assumes that the system will be hardened by replaced all vulnerable transformer (e.g. 

Replacement costs = Installed cost). 

3.3.2 Service Interruptions 

If a space weather event causes a power outage, we estimate costs to U.S. electricity consumers that may be 

~$400 million to ~$10 billion for a moderate event and ~$1 billion to ~$20 billion for a more extreme event. Although 

this potential impact has to date generated the most concern and attention, stakeholders were relentless in emphasizing 

the number of significant uncertainties surrounding this issue. Many stressed that there are currently so many unknowns 

that cost estimates should be carefully caveated. After closely reviewing the technical literature and discussing previous 

cost estimates with stakeholders [e.g. Kappenman, 2010; Oughton et al., 2016; 2017], we better understood the inherent 

challenges but nonetheless proceeded to construct an estimate that would at the very least complement the existing work 

by more closely reflecting where the power industry stands on the issue. Constructing a cost estimate, for example, 

requires making some assertion about which of the various physical effects will cause the power outage. This is 

necessary in order to make appropriate and realistic statements concerning the likely spatial and temporal scales of the 

outage which are both first-order controls on costs. Other important assumptions fundamental to assessing the costs of 

potential outages include the location, time of day, season of year, and the real-time information about the grid (e.g. 

generation location/sources, load, etc.). Moreover, stakeholders emphasize that the U.S. has not yet directly experienced 

a space weather related power outage. Our moderate event estimate of ~$400 million to ~$10 billion is therefore based 

on a hypothetical event that causes protective relays to mis-operate and in turn leads to a power outage that is 

commensurate in duration and scale with the Quebec 1989 storm. Our extreme event estimate of ~$1 billion to ~$20 

billion is based on a series of iterative conversations we had with stakeholders and scientists. We relied on this input to 

make the best possible assumptions about the most important controlling factors on the potential cost of this impact 
19

including, (1) which physical effect might cause the impact (reactive power consumption) and (2) the most likely scale 

(cascades across energy market) and duration (~9 hours) of the power outage. Note that ~9 hours corresponds to the 

length of time necessary to recover power once it is lost and assuming no equipment damage. If a space weather event 

causes a prolonged disturbance or causes extensive equipment damage that delays the recovery effort, the outage could 

be longer in duration. Note that there is no established protocol to follow when attempting to construct such estimates 

and the most appropriate methodology to use ultimately depends on the goal of a study. We emphasize that our estimates 

are intended to illustrate the power industry perspective and therefore complement the few other existing works which, 

for example, were instead driven by the insurance industry’s desire to explore the upper-most catastrophic outages 

scenario in order to better understand what financial responsibilities might fall under their purview [Oughton et al.,

2016]. 

3.3.2.a. Moderate Event Scenario

We estimate that a moderate space weather event may cost U.S. consumers of electricity ~$400 million to ~$10 

billion depending on where within the US it occurs. This estimate assumes a power outage that lasts ~6 hours, reflecting 

one similar in duration to the one occurring as a result of the Quebec 1989 storm [Oughton et al., 2017]. It reflects two 

independent estimates that are each based on a different metric describing the scale of this historic outage: (1) The 

amount of power lost (~14.5 to 19 GW) and (2) the number of customers left without electricity (~6 million) [Oughton 

et al., 2017]. We chose to develop two independent cost estimates because we were unable to find detailed studies or 

original references to better understand the scale of this historic outage. Our first estimate is based on the amount of lost 

power which yields a lower cost estimate of ~$400 million to ~$2 billion, whereas our second estimate based on the 

number of impacted customers yield a higher estimate of ~$4 billion to ~$10 billion. 

For our first estimate, we assume that a moderate space weather event causes a power loss of ~14.5 to 19 GW 

for ~6 hours so the resulting energy loss totals ~87 to 114 GWh. Multiplying this energy loss by the U.S. national range 

for the Value of Lost Load (VOLL), $5,000 to $10,000 per MWh (London Economic International LLC, 2013), suggests 

a cost that is ~$400 million to ~$2 billion. Although using the national range for VOLL allows for a tractable and 

straightforward estimate, the cost of a given duration outage (e.g. 6 hours) varies dramatically with geography since 

different areas have different customers bases (e.g. commercial, industrial, and residential users). We nonetheless 

present this simple VOLL-based estimate because it represents a standard and transparent approach for quantifying how 

electricity customers may be impacted by a power supply interruption of a given duration [London Economic 

International LLC, 2013]. 

For our second estimate, we instead assume that the event causes ~6 million electricity users to lose power. To 

explore stakeholder concerns that cost estimates are sensitive to assumptions about where in the nation the outage occurs, 

we calculated costs estimates for individual states and different regions of the country (Table 8) using state-level data 

provided by the Energy Information Agency and the Department of Energy’s Interruption Cost Estimate (ICE) Calculator 

(for additional details, see footnotes in Table 8). We found that an outage impacting ~6 million U.S. electricity customers 

could cost anywhere from ~$4 billion if it occurred in New England to ~$6 billion if it occurred in the West North 

Central region (Iowa, Kansas, Minnesota, Montana, Nebraska, North Dakota, and South Dakota). Since stakeholders 

emphasize that it is not possible to know where exactly an outage may occur, we use the full range of U.S. values for a 
20

cost estimate for the event that is ~$4 billion to ~$10 billion. At this point in time, we are unable to integrate important

but not yet known information about the probability of space weather events causing outage in these different locations. 

Our estimate therefore only reflects the consequences of an outage (impacts) in these different locations based on the 

assumption that one occurs. In addition to this geographic variability, these potential Service Interruptions 

asymmetrically impact different types of electricity users. Across the nation, impacts to commercial and industrial users 

would range from ~$1 to ~$10 billion whereas impacts to residential users would only be ~$10 to ~$100 million (Figure 

4). This key result emphasizes the importance of economic valuation studies that use input-output modeling to explore 

how these direct impacts on power users can in turn impact (“indirect impacts”) upstream and downstream industries 

[Oughton et al., 2017]. 

Table 8. Costs of outage that could occur during a moderate event will depend on where it occurs. 

Region1 States1

Total # of 

Customers 

(in 2015)1

% of Customers 

Impacted2 Cost to 

Customers

New England CT, ME, MA, NH, RI, VT 7,224,700 83% ~$4 b

Middle Atlantic NJ, NY, PA 18,174,969 33% ~$4 b

East North Central IL, IN, MI, OH, WI 22,310,236 27% ~$4 b

West North Central IA, KS, MN, MO, NE, ND, SD 10,817,289 55% ~$6 b

South Atlantic DE, DC, FL, GA, MD, NC, SC, VA, WV 30,532,365 20% ~$4 b

East South Central AL, KY, MS, TN 9,580,016 63% ~$5 b

West South Central AR, LA, OK, TX 17,811,548 34% ~$5 b

Mountain AZ, CO, ID, MT, NV, NM, UT, WY 10,862,155 55% ~$5 b

Pacific Contiguous CA, OR, WA 20,495,811 29% ~$5 b

Pacific 

Noncontiguous AK, HI 823,933 100% ~$2s b

Total 148,633,002 4 % ~$5 b

1

Information from the 2015 Total Electric Industry Customers, reported in Table 1 by the Energy Information Agency (Summary 

of data form EIA-861-schedules 4A, 4B, EIA-861S and EIA-861U), available at https://www.eia.gov/electricity/data.php#sales

2Percentage of region impacted is calculated by dividing the total number of people assumed to be impacted by the outage (6 

million customers) by the total number of customers within the region. 

3Cost of outage calculated by first using the U.S. Department of Energy’s (DOE) Interruption Cost Estimate (ICE) Calculator 

(available at http://www.icecalculator.com/ ) to estimate the costs of a 6 hour outage to all states within each region (100% of 

customers) and then multiplying results by the % of customers within the region that would actually be impacted. 
21

Figure 3. Cost estimates of a ~6 hour outage vary dramatically from state-to-state. Numbers in below figure derived 

by using state-level data provided by the Energy Information Agency and the Department of Energy’s Interruption 

Cost Estimate (ICE) Calculator (for additional details, see footnotes in Table 8). The below results demonstrate that 

the costs of a ~6 hour power outage to different U.S. states depends on where the outage occurs and may ranges from 

~$100s of millions to ~$10 billion. 
22

Figure 4. Costs of 6 hour outage (100% of customers) to different regions of the U.S. Note that Service Interruptions 

disproportionately impact different types of electricity users. Impacts to Commercial and Industrial users are $1 to $10 

billion whereas impacts to Residential users are ~$10 to $100 million. 

Figure 5. Cost estimate for moderate event that causes a ~6 hour outage impacting ~6 million customers in different 

regions of the country. Estimates derived using state-level data provided by the Energy Information Agency and the 

Department of Energy’s Interruption Cost Estimate (ICE) Calculator (see Table 8).
23

3.3.2.b. More Extreme Event Scenario 

We estimate that an extreme space weather event may cost U.S. consumers of electricity ~$1 billion to $20 

billion. This reflects the costs of a ~9 hour blackout to an entire U.S. energy market during peak demand. Stakeholder 

conversations helped inform our assumptions about how long the outage might last and how large of an area it might 

affect. Although too early to incorporate insights from the currently ongoing U.S. SWAP extreme benchmark effort 

[Love et al., 2016; Executive Office of the President, 2017], we discuss how insights from SWAP results will help 

bridge some of the many knowledge gaps surrounding the geography of potential power outages caused by space 

weather. Such information, as it becomes available, should be included in cost estimates to build a more robust 

understanding that includes many of the important variables (e.g. geo-electric hazards, network typology, system 

configuration, system load, time of day) necessary for developing more refined cost estimates. 

Although more than one of the physical effects of space weather on the power grid could in theory cause an 

outage during an extreme event, stakeholders note that the most probable outage scenario would be one driven by 

reactive power consumption. This industry insight is important since different assumptions about what triggers the 

outage are necessary to know what statements can be made regarding two first-order controls on potential costs: (1) 

How long the outage might last and (2) how large of an area it may affect. Stakeholders all generally agreed that a 

particularly extreme space weather storm, such as one analogous in size to the Carrington event, might quickly elevate 

reactive power consumption to a level that, if not properly managed by grid operators, could trigger a cascading 

outage. Although a cascading outage could potentially impact an entire U.S. electricity market, they noted that it is 

very unlikely that it would be able to cross grid interconnections to impact neighboring markets. Specifically, grid 

interconnections in the U.S. are typically separated by a set of direct DC tie lines and therefore are not synchronously 

tied together with the AC transmission lines where the reactive power consumption effect would be occurring (this 

may not be true in certain regions of the U.S. or in other countries). Stakeholders furthermore anticipate that the 

envisioned outage might last at most ~9 hours. The duration of this Service Interruption is commensurate with other 

recent examples of cascading outages that have impacted large areas (e.g. the Hydro-Quebec outage in 1989, the 

Western North American outages in 1996, and the Northeast outage in 2003) but that have not involved significant 

infrastructural damage. Although the last two of these outages were not caused by space weather, considering them 

as analogous events is appropriate since they require similar recovery efforts and procedures and therefore share 

similar outage durations. To translate these stakeholder insights on duration and scale into monetary terms, we 

calculated the costs of a 9 hour outage across the different U.S. electricity markets using the national range for the 

VOLL (Table 9). We found cost estimates that vary by over an order of magnitude. Estimated costs are lowest if the 

extreme event impacts New England (~$1 billion to ~$3 billion) and highest if the event instead impacts the Southeast 

(~$7 billion to ~$20 billion). As for our moderate event, we were unable to integrate into our analysis important but 

not yet known information about the probability of space weather events causing outage in these different locations. 

Our estimate therefore only reflects the consequences of an outage (impacts) in these different locations based on the 

assumption that one occurs. Note that these numbers reflect an upper limit on our extreme scenario since we assume 

that the event occurs during that market’s peak demand. Note that we were unable to use the ICE in this scenario 

because electricity markets are not organized along discrete state boundaries, the fundamental unit of analysis for this 

online tool (both methods are similar in that they use the VOLL methodology). 
24

Although it is hard to predict where within the U.S. an extreme event may be most likely to cause an outage, 

early results of an initial effort to systematically explore this hazard at the national scale have recently been published 

[Love et al., 2016]. It is important to note, however, that the geo-electric hazard is only loosely related to the actual 

GIC flow in the power system and is but one of the many other variables that needs to be known in order to rigorously 

assess if an outage will occur and with what level of associated costs. Therefore our initial estimate should be revisited 

and updated as more information is acquired. 

Table 9. The upper limit on the potential cost of a nine hour power outage that cascades across all electric power 

markets. The worst-case estimate assumes that the event causes a power outage that coincides with peak energy 

demand in each of the electric power markets. Given that the highest geo-electric hazard associated with the 1-in100 year benchmark scenario occurs within MISO, we use the cost of the outage in MISO as our worst-case extreme 

estimate. 

Electric Power Market1 Peak Demand (MW)1 Cost of 9 hr outage2

California (CAISO) 50,000 ~$2-5 b

Midcontinent ISO (MISO) 127,125 ~$6-10 b

New England (ISO-NE) 28,130 ~$1-3 b

New York (NYISO) 33,956 ~$1- 3 b

Northwest 69,621 ~$3-6 b

PJM 165,492 ~$8-10 b

Southeast 170,000 ~$8-20 b

Southwest 42,000 ~$2-4 b

SPP 45,279 ~$2-4 b

Texas 69,621 ~$3-6 b

1Peak-demand for each Electric Power Market provided by FERC (https://www.ferc.gov/market-oversight/mktelectric/overview.asp)

2Costs of worst case outage calculated by multiplying peak demand by 9 hours (to estimate total MWh lost) and 

using the national range for the VOLL of $5,000 to $10,000 per MWh). 

3.4. Power References

Cannon, P., Angling, M., Barclay, L., Curry, C., Dyer, C., Edwards, R., et al., 2013. Extreme space weather: impacts 

on engineered systems and infrastructure, UK Royal Academy of Engineering, London, ISBN 1-903496-95-0.

Forbes, K. F., and O. C. St. Cyr (2010), An anatomy of space weather’s electricity market impact: Case of the PJM 

power grid and the performance of its 500 kV transformers, Space Weather, 8, S09004, 

doi:10.1029/2009SW000498.

Forbes, K. F., and O. C. St. Cyr (2012), Did geomagnetic activity challenge electric power reliability

 during solar cycle 23? Evidence from the PJM regional transmission organization in North America, Space 

Weather, 10, S05001, doi:10.1029/2011SW000752.

Gaunt, C.T. and G. Coetzee. 2007. Transformer failures in regions incorrectly considered to have low GIC-risk. 2007 

IEEE Lausanne Power Tech.

Kappenman, J. 2010. Geomagnetic Storms and Their Impacts on the U.S. Power Grid. Metatech Corporation.

London Economic International LLC, 2014, Estimating the Value of Lost Load: Briefing paper prepared for the 

Electric Reliability Council of Texas, Inc. 
25

Love, J. J., Pulkkinen, A., Bedrosian, P. A., Jonas, S., Kelbert, A., Rigler, E. J., Finn, C. A., Balch, C. C., Rutledge, R., 

Waggel, R. M., Sabata, A. T., Kozyra, J. U. & Black, C. E., 2016. Geoelectric hazard maps for the continental 

United States, Geophys. Res. Lett., 43(18), 9415-9424, doi:10.1002/2016GL070469.

Oughton, E., J. Copic, A. Skelton, V. Kesaite, Z.Y. Yeo, S.J. Ruffle, M. Tuveson, A.W. Coburn, and D. Ralph. 2016. 

Helios Solar Storm Scenario. Cambridge Risk Framework series. Centre for Risk Studies, University of 

Cambridge.

Price, P. R. (2002), Geomagnetically induced current effects on transformers,

 IEEE Trans. Power Delivery, 17, 1002–1008, doi:10.1109/TPWRD.2002.803710.

Pulkkinen, A., S. Lindahl, A. Viljanen, and R. Pirjola (2005), Geomagnetic storm of 29–31 October 2003: 

Geomagnetically induced currents and their relation to problems in the Swedish high-voltage power 

transmission system, Space Weather, 3, S08C03, doi:10.1029/2004SW000123.

Pulkkinen, A., Bernabeu, E., Thomson, A., Viljanen, A., Pirjola, R., Boteler, D., Eichner, J., Cilliers, P. J., Welling, 

D., Savani, N. P., Weigel, R. S., Love, J. J., Balch, C., Ngwira, C. M., Crowley, G., Schultz, A., Kataoka, 

R., Anderson, B., Fugate, D., Simpson, J. J. & MacAlester M., 2017. Geomagnetically induced currents: 

Science, engineering and applications readiness, Space Weather, 15, doi:10.1002/2016SW001501.

Rezaei-Zare, A., and L. Marti, 2013. Generator thermal stress during a Geomagnetic Disturbance," 2013 IEEE Power 

& Energy Society General Meeting, Vancouver, BC. pp. 1-5. 

doi: 10.1109/PESMG.2013.6672072

Tay, H.C., and G. W. Swift, 1985. On the problem of transformer overheating due to geomagnetically induced 

currents, IEEE Trans. Power Appar. Syst., PAS‐104(1), 212–219, doi:10.1109/TPAS.1985.318916.
26

4. Satellites 

4.1 Impact Mechanisms

Enhanced radiation resulting from space weather events can affect satellites in different ways and vary in 

response to many factors such as orbit, design, and age. Space weather induced increase in particulate radiation affects 

satellites and can cause a range of anomalous satellite behaviors. Anomalies may result if charges gradually 

accumulate and then suddenly discharge on either spacecraft surfaces (“surface charging”) or in some of their interior 

components (“internal charging”) [Garrett, 1981; Baker et al., 1994; Fennell et al., 2001; Baker and Lanzerotti, 2016]. 

Anomalies may also result when single particles deposit charge near sensitive microelectronics. Examples of anomalous 

satellite behaviors potentially attributable to space weather range in severity and can include software glitches such as 

bit flips or phantom commands to partial or complete damage of critical hardware components such as those related to 

power, navigation, and/or communication [Bedingfield et al., 1996; Lohmeyer et al., 2015; Baker and Lanzerotti, 2016]. 

In addition to satellite anomalies, which are acute in the sense that they tend to occur at the time of a space weather 

event, enhanced levels of particulate radiation can also represent a chronic problem by increasing the cumulative dosage

of radiation received by a satellite. This can accelerate physical processes such as material embrittlement, displacement 

damage (e.g. damage to lattice structure of satellite materials), and surface erosion that may prematurely age and shorten 

the functional capacity and/or lifetime of satellites [Cannon et al., 2013; Baker and Lanzerotti, 2016]. Increases in 

ultraviolet radiation can also affect satellites, by heating the atmosphere and increasing the ambient density of the 

thermosphere. This is known to increase the drag force on satellites in Low Earth Orbits (LEO) (altitudes <~800km) 

which may in turn accelerate altitude losses [Jacchia, 1963; Nwankwo et al., 2015]. Increases in other types of 

electromagnetic radiation may lead to link disruptions, by interfering with the transmission and reception of the signals 

used to send information to and from satellites. Impacts from link disruptions in turn depend on many specifics including 

the criticality of the disrupted information and is considered in detailed in our GNSS user section. 
27

Figure 6. Impact mechanism diagram for satellites outlining the primary causal pathways from a solar event to 

physical effects (grey boxes) that can in turn cause a variety of social and economic impacts (green boxes). Note that 

our illustration depicted is not to scale, not comprehensive, and should be revised with future input from stakeholders 

to ensure it captures largest potential concerns. 

4.2 Stakeholder Perspectives on Impacts

Our first phase of stakeholder outreach involved hour long phone calls with 8 individuals working across the 

satellite industry. We used our satellite sector impact matrix to guide these conversations and to systematically collect 

stakeholder input on the various physical effects of space weather and the types of impacts caused by each. Our final 

impact matrix is presented below (Table 10) along with additional and important insights from these conversations, 

including definitions and notes on the various physical effects (Table 11) and impacts (Table 12). This section provides 

a high-level overview of these discussions. 

Satellite engineers and operators must overcome a range of environmental challenges in order for satellite 

missions in different orbits to provide various types of satellite services. Stakeholders across the industry therefore 

expressed different levels of concern about the different physical effects of space weather on satellites (Table 11) that 
28

tended to reflect fundamental differences between satellite orbits [e.g. Geostationary Earth Orbit (GEO) vs. Medium 

Earth Orbit (MEO) vs. Low Earth Orbit (LEO)] and missions [e.g. commercial communications, navigation, earth 

observations, military surveillance, research & development, meteorology, scientific, civil/military communications]. 

For example, building communication satellites to operate in GEO and Global Navigation Satellite System (GNSS) 

satellites to operate in MEO, where the radiation environment is relatively harsh, involves substantial Defensive 

Investments such as hardened components, shielding, or extra generous design margins to protect the integrity of 

satellites from high cumulative radiation dosages and from anomalous satellite behaviors that can be caused by surfaceand deep-dielectric charging. LEO engineers and operators explained that their assets are comparatively more shielded 

by the atmosphere but nonetheless are concerned about radiation especially under more severe conditions when it 

penetrates further into the atmosphere than normal. They also expressed an additional concern about an extreme space 

weather event and the large number of LEO spacecraft that could potentially lose altitude from excessive atmospheric 

heating. Specifically, the growing orbital population is approaching a level where one accidental collision could trigger 

cascading collisions [e.g. “Kessler Syndrome” (Kessler et al., 2010)] to potentially devastate many critical societal 

services such as earth observations and meteorology.

Although stakeholders emphasized that space weather impacts will be customer and mission dependent, 

stakeholders tended to agree that the largest impact category is Defensive Investments due to the very high costs of 

satellites and high value of their services. Satellite manufactures also noted that they tend to combine information from 

standard industry models and their own experiences when making many different decisions about design and 

engineering. They also noted that spare satellites add redundancy that may be inexpensive if the spare is a 

decommissioned satellite with some remaining capacity or costly if the spare is a new satellite. Stakeholders 

knowledgeable about satellite operations described different Mitigating Actions. Certain operators reported having 

procedures in place for space weather events, however, noted that such actions are infrequently enacted since the 

probability of any particular event impacting a satellite is considered low and the costs and risks of such procedures are 

too high (e.g. losses of revenue or potential problems recovering satellites once switched into safe mode). The preferred 

option at present is to instead observe what happens during an event and respond accordingly. Although not publically 

reported, this may involve non-routine operations and additional workload. Stakeholders noted that this represents an 

insignificant expense under normal conditions since companies have trained personnel on hand for such instances which 

can also result from other, non-space weather related issues (e.g. manufacturing glitches, terrestrial weather). Despite 

these concerns, most industry stakeholders emphasized that the satellite population is rather robust and that the challenges 

posed by space weather events are manageable, with some operational inconveniences but without any impacts to the 

end users of satellite services. Although the possibility of an event leading to Asset Damages and Service Interruptions 

is highly unlikely from their perspective, they noted that it cannot be ruled out and would furthermore be devastating if 

it occurred. 
29

Table 10. Impact matrix populated during stakeholder outreach to better understand how the known physical effects of space weather on satellites can 

cause different types of impacts. Items in the matrix reflect example impacts and we tried to capture stakeholder thoughts on differences between impacts 

that might occur during moderate (normal text) compared to more extreme (italic text) space weather conditions. Question marks denote instances where 

the physical effect may in theory be able to cause this impact but empirical support is lacking. *Additional details pertaining to a select set of these 

impacts can be found in Table 12. 

Physical Effects

Impact Categories

Defensive 

Investments Mitigating Actions Asset Damage Service Interruptions Health Effects

Loss of Altitude 

(LEO only)

•Design & 

Engineering*

•Situational awareness

•Insurance

•Spares*

•Unplanned 

operations*

•Fire thrusters

•Accelerated aging*

•Asset loss?*

•Quality degradation*

•Outages?*

Link Disruptions

•Design & 

Engineering*

•Situational awareness 

•Diversification

•Unplanned operations*

•Schedule changes •Quality degradation*

•Outages?*

Anomalies

•Insurance 

•Design & 

Engineering*

•Situational awareness

•Environmental 

testing

•Spares*

•Diversification

•Anomaly 

investigations*

•Safe mode

•Accelerated aging*

•Asset loss*

•Quality degradation*

•Outages?*

Cumulative Dosage

•Design & 

Engineering*

•Situation awareness

•Environmental 

testing

•Accelerated Aging*

•Asset loss?*

•Quality degradation*

•Outages?*
30

Table 11. Space weather can cause a variety of physical effects to satellites. These physical effects, defined below, 

are relatively well-studied in the scientific and engineering literature. These physical effects were discussed with 

industry stakeholders in order to better understand their potential for causing different types of impacts. These 

physical effects are connected to impacts in Table 10, with details on impacts provided in Table 12. 

Physical Effect Definition Notes from Stakeholder Outreach

Cumulative 

Dosage

Total amount of 

ionizing or non-ionizing 

radiation that a satellite 

is exposed to over its 

lifetime. 

• Very dependent on mission profile, standards are relaxed for LEOs and highest for 

MEOs and GEOs. 

• Physical effect is a natural and accepted process within the industry that causes slow 

and steady wear and tear. Conservatively accounted for with engineering and design. 

• Over engineering (x2-3 margin is typical) is costly but less costly than trying to

perfectly design a satellite (lifetime ends with planned mission) or losing one early.

• Experience suggests that solar minimum may be more damaging to satellites since 

strong solar activity shields them from really damaging heavy ions in cosmic rays. 

• Increasing usage of Commercial Off-the-Shelf Technologies with lower cumulative 

dosage specifications currently represents an unknown risk since satellites using these 

parts have not been tested in recent years by space weather. 

• Degrade all components on the satellite, including payload and bus. 

Anomalies Any malfunction in the 

normal, anticipated 

behavior of a satellite or 

satellite sub-system (e.g. 

power, attitude, 

stability, orientation) 

that is not readily 

explainable. 

• A range of malfunctions are possible and require increased workload for operators to 

troubleshoot and restore nominal operations. Anomalies are rarely severe enough to 

impact the provision of satellite services and can be non-space weather related. 

• A large portion of anomalies are recurring, novel ones are more resource intensive 

and resolving them can carry significant expense. 

• Some designs are more susceptible than others and resolving anomalies requires 

contingency procedures that have operational costs. 

• Only anomalies that decrease the capability of the satellite are key concern. 

• Impact depends on technology satellite utilizes, its function, and how event impacts 

that specific technology (e.g. momentum wheels, star trackers, etc.). 

Link 

Disruptions

Any degradation or 

interruption in the 

propagation or reception 

of signals used to 

transmit information to 

or from a satellite.

• Reliability of a particular satellite linkage is more often diminished due to a variety 

of non-space weather reasons (e.g. rain, weather).

• Probability of occurring depends on what bands are being used to send/receive signals 

and how space whether affects these bands. Satellites use different signal frequencies 

for Telemetry, Tracking, and Control (TT&C) and for providing services. 

• Costs escalate quickly in order to attain high levels of reliability and therefore depend 

on value of service to end user and also their budget. 

• For commercial satellites that have to send and receive signals 24/7 so any 

interruption in the signal (even one minute) is problematic. Time is money and costs 

scale non-linearly with the length of time a signal problem lasts. 

• Of large concern to satellite operators because they can directly impact revenues. 

Loss of Altitude Lowering of satellite 

velocity and in turn 

altitude, due to 

increased atmospheric 

drag. 

• Normal process that space weather can simply accelerate. 

• Loss of altitude due to increase in drag force relevant for LEO satellites only. Small 

losses (~10s-100s m) only trigger action if they introduce collision hazards but larger 

losses (~1-10s km) may trigger repositioning. Events where thrusters have to be 

fired are of special concern since it depletes fuel and fuel ends up being key constraint 

on mission lifetime.

• Effect may become more problematic as airspace becomes more crowded: One 

collision initiated by space weather could trigger cascading collisions (e.g. “Kessler 

Syndrome”). 
31

Table 12. Additional details on a select set of space weather impacts in our impact matrix (Table 10) identified during 

stakeholder outreach. 

Impact 

Category Examples Definition Notes from Stakeholder Outreach

Defensive 

Investments

Design and 

engineering

A range of engineering 

solutions that protect against 

space weather impacts such as 

component redundancies, 

physical shielding, radiation 

hardening, factors of safety, 

groundings/coatings, error 

detection/correction software, 

and end of lifetime designs. 

 Many decisions that all vary with satellite mission profile (e.g. orbit, 

performance, lifetime) and differ between manufacturers and customer. 

 Engineers start at end of mission lifetime and work backwards, building 

in margins that are ~10-50% at the end of life. 

 Can include spare capacity and cold vs. hot redundant systems. 

Diversity also helps: dissimilar units can provide a replacement 

capability when the other fails (e.g. Telecommand using different 

frequency receivers). 

Spares

Operators may have extra 

satellites to replace satellites 

that are temporarily inoperable 

or permanently lost. Note that 

onboard spare capacity (e.g. 

redundant units) is part of 

Design & Engineering. 

 Spares can be in space (“on-orbit”) and simply moved into necessary 

slot or stored on the ground and can be launched. 

 On-orbit spares can be new or old, decommissioned satellites that still 

function. More typical for satellites that belong to constellations (e.g. 

LEOs and MEOs) but GEO spares may also be invested in. 

 New spares, either on-orbit on the ground, are big economic 

investments. 

Mitigating 

Actions

Unplanned 

operations

Any unplanned operational 

procedure that results in nonnominal operations. Example 

may be recalibrating orientation 

equipment or firing thrusters to 

regain lost altitude or velocity. 

 Maintenance to bring sub-systems back into range. 

 Operators report no or rare incidences when they have had to fire 

thrusters but a concerning event would be one that consumes a 

significant % of fuel reserve. 

 Operations that consume fuel (e.g. fire thrusters) are biggest deal as fuel 

is key constraint on mission lifetime. 

Anomaly 

investigations

Assessment conducted after any 

anomalous satellite behavior is 

observed to understand likely 

cause and potential solutions. 

Note that most anomalies are 

not related to space weather but 

rate of anomalies is known to 

increase during events. 

 Diagnosing the origin of an anomaly is important because the concern 

is that an anomaly could (but often does not) decrease capability. 

 Minor investigations can require couple of hours to days and be done 

by one person. Major investigations can require weeks to years and 

may require a team of people that have to consult with manufactures, 

troubleshoot extensively, and run many computational simulations. 

 Societal implications are potentially large. Need quick diagnosis if 

anomaly cause is from space weather or humans (e.g. terrorists).

Asset 

Damages

Accelerated 

aging

Any reduction in the capacity of 

satellite sub-systems (e.g. 

power, power storage, 

transponders) that is faster than 

anticipated and could shorten 

the lifetime of a satellite. 

 A 4-5% reduction in capacity of satellite sub-systems is assumed and 

planned for. Power systems often have higher margins, ~10-20%. 

 Accelerated aging is only problematic if it reduces satellite lifetime or 

causes prime unit failures. 

 Ionizing vs. non-ionizing radiation causes different type of aging 

effects. 

Asset Loss

Permanent discontinuation of a 

satellite’s functionality that can 

occur either before or after it 

has exceeded its planned 

mission lifetime. 

 If lost after planned lifetime, the loss in functionality and revenue is 

unfortunate but the satellite has already exceeded planned life. 

 If lost before planned lifetime, economic loss can be devastating since 

service revenue has not yet paid for invested costs. Stakeholders note 

that satellites are rarely lost prematurely and usually last longer than 

mission lifetime. 

Service 

Interruptions

Quality 

degradation

Any reduction in the quality of 

satellite services provided 

including noisy data, bad 

images, and dropped calls. 

 Impact depends on many end user specifics.

 Although they would be biggest for those dependent on immediate, 

accurate, and continuous provision of satellite services, such users tend 

to have bigger budgets and invest more in quality assurance. 

Outages Temporary or permanent loss of 

satellite services. 

 Impact depends on many end user specifics. Impact highest for those 

relying on capabilities for primary rather than backup services. 

 When an LEO satellite malfunctions, service disruptions will be 

intermittent and global. When a GEO satellite malfunctions, service 

disruption will be continuous and localized to the satellite footprint. 

 Service options. End users may not be impacted because they could 

change service providers or service provides multiple satellites. Most 

likely to impact smaller businesses. 

 Can be triggered by false commands from space weather. Could result 

if a critical satellite is permanently lost. Critical satellites tend to be 

those in GEO that are expensive and unique. 
32

4.3 Cost Estimates

In order to translate our findings into quantitative cost estimates that capture the most concerning and potentially 

largest impacts, we conducted a second round of stakeholder outreach. After discussing the various possibilities and 

better understanding some of the challenges inherent to quantifying many of the impacts we identified (Table 10), we 

ultimately decided to develop satellite sector cost estimates for Defensive Investments (~$400 to ~$700 million in 2016) 

and Asset Damages (~$200 million to ~$2 billion for our moderate event scenario and ~$2 billion to ~$80 billion for our 

more extreme event scenario). Our cost estimate for Defensive Investments focuses on the potential financial impacts 

of designing and engineering satellites to withstand the physical effects caused by space weather. Our cost estimate for 

Asset Damages examines the possible costs associated with asset losses, including satellite replacement costs and losses 

in revenue. Almost all of our stakeholders agreed that Defensive Investments may represent the largest costs of space 

weather to the industry. They also emphasized that potential Asset Damages represents a worst-case scenario. In 

particular, stakeholders consider the possibility of this happening during an event to be highly unlikely, due to substantial 

Defensive Investments, but noted that it would nonetheless be very costly and is not entirely without precedent. Key 

insights gleaned from these conversations are provided below alongside a description of how they influenced the 

derivation of our cost estimates. 

Table 13. Simplified impact matrix with the focus of our quantitative analysis highlighted in yellow. The presence 

(or absence) of a circle denotes where we were able to connect a given physical effect to a particular impact category 

based on outreach, see Table 10 ). Black circles denote that a physical effect is known, from direct past experience, 

to cause a particular category of societal impact. Open circles indicate that a given physical effect may cause a 

particular category of societal impact, but stakeholders emphasize that this impact lacks empirical support.

Physical Effects

Impact Categories

Defensive 

Investments

Mitigating 

Actions

Asset 

Damages

Service 

Interruptions

Health

Effects

Cumulative Dose ● ○ ○

Anomalies ● ● ● ●

Link Disruptions ● ● ●

Loss of Altitude1 ● ○ ○ ○

1Only applicable to LEO satellites

4.3.1 Defensive Investments

We estimate that building satellites capable of withstanding space weather may have cost U.S. manufactures 

~$400 to ~$700 million in 2016 (Table 14). This estimate aims to capture what we heard from many of the engaged 

stakeholders during this study. The impacts of space weather events on satellites to date are relatively low because the 

industry carefully addresses the well-recognized hazard with appropriate design and engineering measures. Although 

many stakeholders thought that the largest costs to the industry would be associated with this impact category, they noted 

that substantial Defensive Investments are warranted and justified because losing a satellite or the services it provides 

would be far more economically devastating. 

We derived our estimate for Defensive Investments by combining manufacturing revenue data provided by the 
33

Satellite Industry Association [SIA, 2017] with stakeholder best judgement on the proportion of satellite manufacturing 

costs that may be attributable to defense from space weather. Although many specific satellite details on both topics 

represent well-kept trade secrets, stakeholders were able to offer general but important insights on the manufacturing 

process and its related costs. They discussed, for example, the complexity of various design and engineering decisions 

and the considerable variation between mission types (e.g. orbital regime and planned lifetime), manufacturers (e.g. 

experience and business strategy), and customers (e.g. service requirements, budget and risk aversion). For the best 

financial data, they pointed us to publically available information that is collected, aggregated, and reported annually by 

the Satellite Industry Association (SIA). According to the most recent SIA report [SIA, 2017], manufacturing revenues 

from satellites launched in 2016 totaled ~$13.9 billion globally. Global revenue is further broken down in the report by 

mission type, allowing us to calculate how much was spent on different types of satellite missions in 2016 (Table 14). 

Since stakeholders were unable to discuss specific design and engineering details, we instead probed for 

estimates of how much space weather might add to the manufacturing costs of a satellite. Stakeholders had a hard time 

answering this question despite finding it relatively easy to list many examples of Defensive Investments and knowing 

that each involved significant expenses (for details, see Table 12). One stakeholder, for example, noted that a radiation 

hardened component may cost orders of magnitude more than an analogous, non-radiation hardened component. 

However another noted that the physical parts of a satellite represent a very small percentage of a satellite’s total cost: 

The majority of a satellite’s costs is instead attributable to the painstaking design, engineering, and testing efforts (e.g. 

environmental simulations, space qualifying, performance testing and reviews etc.) that goes into ensuring that it will 

reliably operate and provide the planned services in the harsh space environment throughout its planned mission lifetime. 

Although hard to quantify what percentage of this total effort might be attributable specifically to space weather, a few 

stakeholders independently provided similar estimates that it might represent somewhere between ~1% and ~10% of a 

satellite’s manufacturing costs. These individuals further noted that the lower end of this range (~1-5%) would apply to 

satellites with recurring engineering (RE) while the higher end (~6-10%) to those with non-recurring engineering (NRE) 

due to one-time production costs (e.g. research, development, design, and testing)1. To estimate how much might have 

been spent across the global satellite industry in 2016, we multiplied our previously derived manufacturing revenues 

[SIA, 2017] by these percentages based on whether a mission type typically involves RE or NRE (Table 14). Global 

revenues associated with the manufacturing of satellites for military surveillance, for example, were $6.1 billion in 2016. 

Since these satellites typically entail NRE, Defensive Investments were estimated to be 6 percent to 10 percent of total 

revenues, or ~$400 million to ~$600 million. Similar computations were performed for each mission type, yielding an 

estimated Defensive Investment cost of ~$600 million to ~$1 billion globally in 2016. U.S. firms account for 64 percent 

of the market globally (for all mission types), so the Defensive Investment cost for the U.S. was estimated to range from 

~$400 million to ~$700 million in 2016 (64 percent of the global cost) (Table 14). Note that the aggregated data provided 

by the SIA [2017] does not allow us to provide a more granular cost estimate (broken down by mission type) of U.S. 

Defensive Investments.

 

1 Recurring Engineering (RE) refers to an engineering effort that has been previously researched, tested, and 

successfully implemented. Non-Recurring Engineering (NRE) refers to the novel engineering effort required to bring 

a new product or innovation to market and therefore tends to be more costly. 
34

Table 14. Cost estimate of Defensive Investments made by the global satellite industry in 2016. 

Mission Type1

Global 

Manufacturing 

Revenue2

Recurring 

Engineering 

(RE)3

Non-Recurring 

Engineering 

(NRE)3

Cost Estimate 

of 2016 Defensive Investments

Globally4 U.S.5

Military Surveillance ~$6.1 b ● ~$400-600 m 

Commercial 

Communications

~$2.2 b ● ~$20-100 m

Civil/Military 

Communications

~$0.83 b ● ~$50-80 m

Earth Observations ~$1.7 b ● ~$20-80 m

Navigation (GNSS) ~$1.7 b ● ~$20-80 m

Scientific ~$0.70 b ● ~$40-70 m

Meteorology ~$0.56 b ● ~$30-60 m

Research & 

Development

~$0.14 b ● ~$8-14 m 

Total $13.9 b ~$0.6-1 b6 ~$400-700 m

1Mission Type categories from SIA 2017 which does not report on government or university manufactured satellites. 

2Manufacturing revenue by Mission Type is derived from p. 17 of SIA 2017 by multiplying the total industry manufacturing 

revenue in 2016 ($13.9 billion) by percentage of total revenue attributable to different Mission Types.

3Stakeholders were able to identify which Mission Types tend to utilize Recurring Engineering (RE) versus those that tend to 

involve Non-Recurring Engineering (NRE). 

4Cost of Defensive Investments in 2016 calculated by simply multiply total manufacturing revenues by Mission Type by ~1 to 5% 

or ~6 to 10% for missions involving RE or NRE respectively.

5Derived from SIA 2017 data that U.S. firms earned ~64% of total manufacturing revenues in 2016. 

6The final estimate represents ~5% of total manufacturing revenues in 2016 of ~$13.9 b (p. 17 of SIA 2017). 

4.3.2. Asset Damages 

Our moderate and extreme space weather event scenarios both assume the loss of satellite assets, with costs to 

the U.S. satellite industry estimated at ~$200 million to ~$2 billion and ~$2 billion to ~$80 billion, respectively. Both 

of these estimates assume that space weather causes complete and permanent satellite damage and therefore they account 

for the costs of lost satellite asset values and satellite service revenues. Stakeholders stressed that this potential impact 

represents a worst-case scenario. They consider the possibility of this happening to be highly unlikely, due to substantial 

Defensive Investments discussed above, but noted that it would nonetheless be very costly and is not without precedent. 

Stakeholders therefore encouraged us to base our cost estimates on the industry’s collective experience of this impact 

and noted that it was intractable at this point in time to defensibly connect the magnitude of a space weather event to our 

list of physical effects (Table 11) and ultimately to the number of satellites that may be lost as a result. The cost estimates 

below are therefore based on combining insights from iterative stakeholder discussions with publically available 

information on historic satellite loss numbers, industry financials (e.g. asset values and revenues), and a dataset 

containing information on the ~1,459 operational satellites that were in orbit at the end of 2016 (Union of Concerned 

Scientists Satellite Database). 

4.3.2.a. Moderate Event Scenario 

 

We estimate that a moderate space weather event may cost the U.S. satellite industry ~$200 million to ~$2 

billion, including ~$20 million to ~$500 million of lost asset value and ~$200 million to ~$1 billion in lost revenues (as 
35

discussed in our approach, all numbers are rounded to one significant figure). In order to construct this estimate, 

stakeholders encouraged us to start by reviewing the industry’s collective experience of this impact (Table 15). In the 

last ~20 years, there have been a handful of complete and permanent satellite losses from space weather with only one 

loss observed during any specific event (Table 15) [Cannon et al., 2013]. Our moderate event scenario therefore begins 

by assuming the loss of one satellite. Although this reflects industry’s experience to date, one stakeholder further 

emphasized that this historic loss record is actually quite ambiguous since attributing an observed satellite loss to space 

weather is not straightforward. In certain cases, for example, subsequent investigations have concluded that at least one 

of these losses was not from space weather (e.g. Bodeau, 2007). A different stakeholder also noted that insurance 

companies typically cover space weather related losses in their standard packages, further supporting the low-probability 

nature of this impact. 

Table 15. Historic examples of complete and permanent Asset Damages caused by space weather. 

Event Date1

(Event Name) Satellite1 Orbit1 Cause1 Satellite Type Launch date2 Age at Loss (yr)3

01/11/97 Telstar 401 GEO Anomaly Commercial 

Communications 12/16/93 4

05/19/98 Galaxy IV GEO Anomaly4 Commercial

Communications 06/24/93 5

07/15/00

(Bastille Day)

Astro-D

(ASCA) LEO Loss of Altitude Scientific 02/20/93 8

10/24/03

(Halloween Storm)

MIDORI 2

(ADEOS) LEO Anomaly Scientific 12/14/02 7

01/14/05 Intelsat 804 GEO Anomaly Commercial 

Communications 12/22/97 8

1

Information reported by Cannon et al. 2013

2

Information from http://space.skyrocket.de/ 

3Derived by comparing event/loss date with launch date. 

4Note that further investigations by Bodeau 2007 suggests that this loss was not attributable to space weather. 

In order to quantify the total financial impact of this lost satellite, we assume the loss of one U.S. satellite and 

examine the potential loss of its value. As discussed previously, satellite financial data is proprietary information. Our 

stakeholders could only generally discuss satellite asset values by explaining, for example, that costs vary widely 

depending on the mission profile, manufacturer, and customer. To solicit more specific information, we asked 

stakeholder if they could at least provide their best guess on the asset values for different satellite missions. A few were

willing to offer rough estimates but expressed many hesitations given the wide ranges and large uncertainties (Table 16). 

Therefore we also derived an independent estimate for typical asset values of different satellite missions by combining 

aggregated financial data on satellite manufacturing with satellite launch numbers (both provided in SIA [2017] with 

methodology details provided in Table 16 footnotes). Consistent with stakeholder sentiments, we derived a wide range 

of asset values. Research and Development missions are on the lower end of the spectrum, with costs that may be ~$20 

million per satellite, and Military Surveillance missions are on the upper end with costs that may be ~$500 million per 

satellite. Although we use these derived values in our analysis, future efforts may want to focus on clarifying these 

uncertainties. Since it is not possible to know in advance of the event which satellite type will be the one that will be 

lost, we simply assume this lost satellite might cost anywhere between ~$20 million and $500 million. Note that 
36

individual satellites lost in historical, moderate space weather events have been either a commercial communication 

satellite (estimated here at ~$100 million per satellite) or a scientific satellite (estimated here at ~$200 million per 

satellite) (Table 16). 

In addition to the costs of this lost asset, additional impacts may result from the loss of this satellite’s services. 

Many types of satellite missions provide valuable societal services that are not straightforward to quantify (e.g. military 

surveillance, meteorology, navigation). We therefore assume that the lost satellite was generating revenue (e.g. 

commercial satellites). In order to estimate how much revenue the satellite may have been generating, we combined 

aggregated industry data on satellite service revenues with information from the Union of Concern Science’s (UCS) 

database on operational satellites. At the end of 2016, there were 1,459 operating satellites in orbit (UCS database) that

globally generated a total of $260.5 billion in satellite services revenue [SIA, 2017]. This suggests that the average 

service revenue generated by an average satellite in 2016 was ~$200 million/satellite per year (=$260.5 billion/1,459 

satellites). We derived a similar value of ~$200 million/satellite per year by noting that 594 of these 1,459 operational 

satellite were U.S. assets (UCS database) that collectively generated ~$110.3 billion in revenue in 2016 [SIA, 2017] 

(=$110.3 billion/594 satellites). Note that this reflects a conservative value for the services provided by each satellite 

since it does not account for any non-market, societal benefits generated by satellites. In order to assess how many years 

of revenue may be lost as a result of the event, we returned to the historical loss record (Table 15). Stakeholders noted 

that Scientific Satellites do not generate “revenue” for their owners and have large ranges in planned lifetimes whereas 

Commercial Communication satellites do generate revenue and typically have planned mission lifetimes that are ~10 

years. Based on publically available information (for details, see footnotes in Table 15), we were able to estimate that 

the two Commercial Communication satellites that may have been lost due to space weather, Telstar 401 in 1997 and 

Intelsat 804 in 2005, were ~4 and ~8 years old when lost (Table 15). These historic events therefore resulted in ~6 and 

~2 years of lost revenue for each satellite owner respectively. Combining ~2 to 6 years of lost revenue with our previous 

estimate of the amount of revenue the satellite may have been generating (~$200 million/year) suggests a financial impact 

that may be ~$200 million to ~$1 billion. Note that this loss only applies if the lost asset in this scenario fails prior to 

the end of its planned life. Loss of revenue from any satellites that have already exceeded their planned lifetimes would 

be unfortunate but not devastating. 
37

Table 16. Typical costs of different types of satellite assets vary my mission type. 

Mission Type1

Typical Asset Values (per satellite)

Stakeholder 

Estimate2

Derived Estimate3

Manufacturing 

Revenue4

2016 Launches

(% of total)5

Final Derived 

Estimate3

Earth Observations $300,000 ~$1.7 b 64 (51%) $30 m

Commercial Communications $200-250 m ~$2.2 b 20 (16%) $100 m

Navigation (GNSS) $200 m ~$1.7 b 13 (10%) $100 m

Military Surveillance $1-2 b ~$6.1 b 13 (10%) $500 m

Research & Development $10-20 m ~$0.14 b 8 (6%) $20 m

Meteorology $150 m ~$0.56 b 4 (3%) $100 m

Scientific $500-750 m ~$0.70 b 4 (3%) $200 m

Civil/Military 

Communications $200-250 m ~$0.83 b 2 (2%) $400 m

Total $13.9 b 126 (100%) ~$20-500 m

1Mission Type list consistent with SIA annual reports (e.g. SIA 2017). 

2Stakeholders were able to provide rough estimates of typical asset values for different Mission Types but noted wide ranges 

and large uncertainties. 

3Given uncertainties surrounding stakeholder estimates, we derived an independent estimate of typical asset values using 

industry data provided in SIA 2017. 

4For additional details, see Table 14

5Lauch numbers derived from p. 7 of SIA 2017, by multiplying percentages by 126 total launches. 

6Derived estimate divides reported manufacturing revenues by number of satellites launched for all Mission Types in 2016.

4.3.2.b. More Extreme Event Scenario 

We estimate that a more extreme event may cost the U.S. satellite industry ~$2 billion to ~$80 billion, 

accounting for both lost asset values and potential losses in satellite revenue. Our extreme scenario follows the 

methodology outlined for our moderate scenario and the only difference is in the assumed number of satellite losses. In 

discussing with industry stakeholders the potential number of satellites that could be lost in an extreme event, for which 

we have no historical experience, most noted that this is very uncertain but nonetheless expect the total number to be 

small. Our extreme scenario therefore assumes the loss of 10 to 100 satellites globally, representing one to two orders 

of magnitude more asset losses than assumed in our moderate event scenario. Note that this level of loss is unprecedented 

to date and would represent ~0.7-7% of all currently operational satellites (1,459 satellites as of the end of 2016). We 

calculate the value of these lost satellite assets at ~$200 million to ~$50 billion (= 10-100 satellites x ~$20-500 million 

per satellite) and the value of their lost service revenues at ~$4 billion to ~$120 billion (= 10-100 satellites x ~$200 

million per satellite per year x 2-6 years). Summing together these estimates suggests a total, global economic impact 

of ~$4 billion to ~$200 billion. As previously discussed, 594 of the 1,459 satellites (~40%) globally are currently 

owned/operated by the U.S. so we assume this portion of our global costs impacts the U.S. for a final estimate of ~$2 

billion to ~$80 billion. 

4.4 Satellite References 

Baker, D.N., S. Kanekal, J. B. Blake, B. Klecker, and G. Rostoker. 1994. Satellite anomalies linked to electron 

increase in the magnetosphere. Eos. Volume 75, Issue 35. Page 401-405.
38

Baker, D.N. and L.J. Lanzerotti. 2016. Resource Letter SW1: Space Weather. American Journal of Physics. Vol. 

84, No. 3.

Bedingfield, K.L., R.D. Leach, and M.B. Alexander. 1996. Spacecraft System Failures and Anomalies Attributed to 

the Natural Space Environment. NASA Reference Publication 1390.

Bodeau, M. Killer electrons from the angry Sun did not stop the pagers. Space Weather. Vol.5, S03006m 2007. 

doi:10.1029/2006SW000266

Fennell, J. F., H. C. Koons, J. L. Roeder, and J. B. Blake (2001), Spacecraft Charging: Observations and Relationship 

to Satellite Anomalies, in Proceedings of 7th Spacecraft Charging Technology Conference, 476, pp. 279–285, 

European Space Agency, Noordwijk, Netherlands.

Garrett, Henry Berry. 1981. The charging of spacecraft surfaces. Reviews of Geophysics. Volume 19, Issue 4. Page 

577-616

Jacchia, L. G. (1964), Influence of solar activity on the Earth’s upper atmosphere, Planet. Space Sci., 12, 355–378, 

doi:10.1016/0032-0633(64)

90032-7.

Kessler, D.J., N.L. Johnson, J.-C. Liou, and M. Matney. 2010. The Kessler Syndrome: Implications to Future Space 

Operations. American Astronautical Society: 33rd Annual AAS Guidance and Control Conference. 6-10 

February 2010

Lohmeyer, Whitney, Ashley Carlton, Frankie Wong, Michael Bodeau, Andrew Kennedy, and Kerri Cahoy. 2015. 

Response of geostationary communications satellite solid-state power amplifiers to high-energy electron 

fluence. Space Weather. Volume 13, Issue 5. Page 298-315.

Nwankwo, Victor U.J., Sandip K. Chakrabarti, and Robert S. Weigel. 2015. Effects of plasma drag on low Earth 

orbiting satellites due to solar forcing induced perturbations and heating. Advances in Space Research. 

Volume 56, Issue 1. Pages 47-56.
39

5. Global Navigation Satellite Systems (GNSS) Users 

5.1 Impact Mechanisms

A space weather event can potentially impact GNSS users by either directly affecting GNSS satellites and/or 

by interfering with the transmission of the broadcasted GNSS signal. This section focuses on potential impacts resulting 

from how space weather is known to physically affect the transmission of GNSS signals (For more information about 

potential impacts to satellites, please see previous section (Satellites) of this report). GNSS signals are sent from GNSS 

satellites via low power radio waves to different GNSS receivers and end users around the globe. These radio waves 

must transit the ionosphere, a region of our Earth’s upper atmosphere (extending from ~70 to 1000 km above sea level) 

comprised of enough ionized molecules and free electrons to significantly alter their propagation [Hernández-Pajares et 

al., 2011]. The nature and extent of this alteration depends largely on the number of electrons encountered by these 

radio waves. This varies dramatically under background or non-space weather conditions, since electron density in the 

ionosphere varies spatially (e.g. vertically and horizontally, small- and large-scale variations) and temporally (e.g. solar 

cycle variations (~11 years), seasonal changes, dawn/dusk instabilities, rolling disturbances) [for an overview, see 

Hernández-Pajares et al., 2011 and references therein]. Space weather events can cause additional variations to the 

electron density of the ionosphere and therefore alterations to the propagation of GNSS signals, introducing additional 

complexities that are not yet fully understood but are known to affect GNSS users in at least two ways [e.g. Kintner et 

al., 2007; Tsurutani et al., 2009; Cannon et al., 2013; Baker and Lanzerotti, 2016]. First, when space weather events 

sufficiently disturb the ionosphere from background (modeled) conditions, unaccounted for changes in the propagation 

speed of the GNSS signal can lead to ranging errors. Second, they can modify signal-to-noise ratios, preventing GNSS 

users from tracking or “locking” onto GNSS satellites. This can degrade or even prevent GNSS signal reception (e.g. 

Loss of lock). For example, small-scale variations in electron densities (ionospheric scintillations) are known to cause 

significant variations in both the phase and amplitude of GNSS signals [e.g. Kintner et. al., 2007]. Enhanced levels of 

solar radio noise emitted by solar flares can also overwhelm the GNSS signal, by increasing the total amount of noise in 

the system to also result in loss of lock [Cerruti et al., 2006; Cerruti et al., 2008; Tsurutani et al., 2009]. The physical 

effects can impact different GNSS users in different ways, depending on their utilization and reliance on the Positioning, 

Navigation, and Timing (PNT) information provided by GNSS satellites. 
40

Figure 7. Impact mechanism diagram for GNSS users outlining the primary causal pathways from a solar event to 

physical effects (grey boxes) that can in turn cause a variety of social and economic impacts (green boxes). Note that 

our illustration depicted is not to scale, not comprehensive, and should be revised with future input from stakeholders 

to ensure it captures largest potential concerns. 

5.2 Stakeholder Perspectives on Impacts

Our first phase of stakeholder outreach involved hour long phone calls with four individuals with expertise on 

space weather and GNSS. We used our impact matrix to guide these conversations and to systematically collect input 

on the known physical effects of space weather on the GNSS signal and the types of end user impacts that each may 

cause. Our final impact matrix is presented below (Table 17) along with additional and important insights from these 

conversations, including definitions and notes on the various physical effects (Table 18) and impacts (Table 19). The 

remainder of this section provides a high-level overview of what we learned from these stakeholder discussions.

Of the two known physical effects (Table 18), the stakeholders we spoke to all agreed that loss of lock is more 

concerning than ranging errors. “Lock” means that a GNSS receiver has an established connection with a GNSS satellite 

and can therefore acquire its Position Navigation, and Timing (PNT) information. Loss of lock therefore describes a 

situation where the GNSS user is not receiving a usable GNSS signal from a GNSS satellite. Stakeholders emphasized 

that the likelihood of this physical effect occurring varies dramatically from receiver-to-receiver, depending on many 
41

internal (e.g. design) and external (e.g. geography, time of day) specifics. The possibility that it will ultimately lead to 

an actual GNSS outage for the user also depends on which PNT service the end user needs. A GNSS receiver needs to 

be locked onto at least four satellites for positioning and/or navigation information but only one for timing. Stakeholders 

also noted that overall susceptibilities to this effect may or may not be in process of decreasing due to the increasing 

number of operational (e.g. the U.S.’s Global Positioning System and Russia’s GLONASS) and planned (e.g. the E.U.’s 

Galileo and China’s BeiDou) GNSS constellations. Stakeholders explained that ranging errors are less concerning 

because they can be largely eliminated with dual-frequency receivers. One stakeholder, however, noted that a fairly 

large portion of GNSS users remain reliant on single-frequency receivers. There may therefore be a subset of GNSS 

applications in which ranging errors remain a potentially large issue. 

Stakeholders offered a number of general insights about our social and economic impact categories and

emphasized the large number of important, user specific details that need to be considered when trying to understand 

potential space weather impacts. They were able to readily discuss different Defensive Investments, Service 

Interruptions (Table 17 and Table 19), and the direct relationship between these impact categories. Specifically, there is 

an extraordinarily wide variety of GNSS receivers on the market, which range in price (and therefore quality of GNSS 

service) from ~$10 to upwards of $100,000 each. In addition to end user decisions about what type of GNSS receiver 

to purchase, which involves individual cost-benefit considerations, stakeholders discussed how entities and/or industries 

using GNSS for safety-critical applications typically build external systems to enhance the overall performance of the 

standard GNSS service. These augmentation systems can be either space- or ground-based and tend to be quite costly 

since they require additional hardware and software that needs to be bought, deployed, and maintained. In addition to 

decreasing the potential for impacts during a space weather event, these expensive systems are justified because they 

increase the overall performance of GNSS across a broad spectrum of potential issues (e.g. terrestrial weather, 

intentional/non-intentional interference, multipath problems). Stakeholders also noted that these safety-critical 

applications (e.g. aviation) are not yet exclusively reliant upon GNSS and have retained or developed backup 

technologies and procedures in place to use in situations where GNSS becomes unavailable. 

Our stakeholders found it difficult to populate our impact matrix for Mitigating Actions and Asset Damages. 

They noted that it was theoretically possible to enact different Mitigating Actions in response to a specific space weather 

event, for example by post-processing GNSS derived data or by making schedule changes, but were uncertain if these 

options were standard practice. One individual further speculated that such Mitigating Actions might be evoked and be 

particularly effective for reducing potential impacts of an extreme event. Stakeholders were also unable to identify any 

potential Asset Damages to GNSS users but noted that they could potentially occur more indirectly via Service 

Interruptions. The degradation or disruption of navigation information could, in theory and for example, cause moving 

vehicles such as cars or airplanes to collide with one another or immobile objects. They were unaware, however, of any 

incidences where this potential impact has occurred to date. 

Although these general insights were informative, our stakeholders emphasized that there are many 

complexities and uncertainties surrounding this topic. They stressed, for example, that the probability of the physical 

effects (e.g. ranging errors and loss of lock) leading to a Service Interruption and their resulting consequences both vary 

as widely, and are changing as rapidly, as GNSS use itself. Stakeholders also expressed uncertainties about how these 

impacts have or will change with time. On one hand, GNSS users may be becoming less susceptible to potential space 
42

weather events due to increased understanding and more robust Defensive Investments (e.g. GNSS modernization, 

enhanced receiver design and engineering). On the other hand, the potential consequences of Service Interruptions may 

be simultaneously increasing due to the growing number of GNSS uses and users. As the PNT information provided by 

GNSS technology becomes increasingly relied upon and further embedded into more complex, interdependent systems 

and processes, a better understanding of the potential impacts will become more challenging and also more pressing. 
43

Table 17. Impact matrix populated during our first round of stakeholder outreach to better understand how the well-studied physical effects of space weather on GNSS 

users may lead to different categories of social and economic impacts. Bulleted items inside matrix reflect example impacts identified by space weather for both 

moderate and extreme storms. Question marks denote instances where the physical effect may in theory be able to cause this impact but empirical support is lacking. 

Additional notes about each of these impacts from our discussions can be found in Table 18 and Table 19. 

Physical 

Effects

Impact Categories

Defensive Investments Mitigating

Actions

Asset

Damage

Service Interruptions Health 

Effects

Ranging 

Errors

•Receiver Design & 

Engineering

•Additional constellations

•Augmentation Systems

•Differential Correction? •Quality Degradation 

Loss of Lock

•Receiver Design & 

Engineering

•Additional constellations

•Augmentation Systems

•Schedule Changes? •Quality Degradation

•Outage
44

Table 18. Space weather is known to physically affect the transmission of GNSS signals in a variety of ways, with a 

few examples defined below that are relatively well studied in the scientific and engineering literature. The physical 

effects of space weather on GNSS satellites are also addressed in another section of this report. We discussed these 

physical effects with knowledge stakeholders in order to better understand their potential for causing different types of 

social and economic impacts (Table 19). 

Physical 

Effects Definition Notes from Stakeholder Outreach

GNSS 

Satellites*

(For list of 

physical 

effects on 

satellites, 

see Table 

11). 

Any direct impact to 

GNSS satellites that 

interferes with the 

normal operations 

and/or performance 

• GNSS satellites remain military/government investments and therefore 

may be even more conservatively designed and therefore more robust 

than many commercial satellites where cost tends to be a bigger 

constraint and consideration. 

• Uncertain if any GNSS satellites have been acutely impacted by any 

space weather event to date. Also uncertain the degree to which historic 

events may be adding up (chronic impacts). 

• The increasing number of GNSS constellations in orbit, launched by 

other countries, can provide redundancy and may increase impact 

threshold. 

• GNSS is moving towards dual- and multiple-frequency signals and 

receivers, increasing impact threshold. 

Ranging 

Errors 

Inaccurate 

Positioning, 

Navigation, Timing 

(PNT) information 

caused by 

unaccounted for 

changes in the 

propagation speed of 

the GNSS signal 

through the 

ionosphere. 

• This only affects GNSS users with single-frequency receivers. 

• This is also caused by other phenomena (e.g. rain, humidity, and physical 

obstructions) and can be eliminated by using a dual-frequency receiver.

• Under normal non-disturbed conditions, the standard positioning 

accuracy of single- vs. dual-frequency receivers is ~1 meter vs. ~1cm. 

Large disturbances caused by space weather may be able to reduce the 

baseline accuracy of single-frequency receivers by one or two orders of 

magnitude (~10 to ~100 meters) whereas dual-frequency receivers are 

largely impervious. 

• The potential that this physical effect will lead to problems is 

idiosyncratic and depends on many GNSS user details that are not easily 

generalizable (e.g. specific GNSS application and service requirements). 

Although ranging errors would cause the most problems for highaccuracy, real-time applications (e.g. off-shore drilling) needing 

continuously available PNT information of a known quality, these users 

typically make substantial Defensive Investments. Impacts to them 

might therefore be eliminated or else occur at a much higher impact 

threshold. 

Loss of 

Lock 

Inability of a GNSS 

satellite signal to be 

tracked by a receiver, 

reducing the number 

of usable satellites in 

the sky. 

• Susceptibility to this physical effect is receiver dependent. 

• Loss of lock leads to outage if receiver cannot lock onto at least 4 

satellites for positioning and navigation and at least one satellite for 

timing. 

• Amount of time to recover from loss of lock is also receiver dependent. 

Reacquiring a signal can be nearly instantaneous or it can take ~30 mins 

to an hour to get high-precision services back. 

• Uncertain how often this will occur during the next solar cycle since there 

will be many more GNSS constellations/satellites in the sky then. 
45

Table 19. Additional notes from stakeholder discussions on items listed in our final GNSS impact matrix (Table 17)

Impact 

Category Examples Definition Notes from Stakeholder Outreach

Defensive 

Investments

Receiver 

Design and 

Engineering

A variety of techniques used by 

GNSS receiver manufacturers to 

increase GNSS service quality 

including, for example, special 

computer algorithms, holdover 

technologies (e.g. highly 

accurate internal 

synchronization devices), 

increasing the maximum age of 

corrections, and inertial 

navigation systems. 

 Depends on user needs. 

 Also varies with geography and becomes especially important in 

areas where reliability of GNSS signal is a chronic problem (e.g. 

high-latitudes, equatorial regions). 

 Holdover capacity is application specific but can range from 

hours to days. Holdover is invested in for other reasons besides 

space weather and can be costly. To maintain accuracy for 5 

minutes without GNSS signal, for example, may cost ~$100,000.

Additional 

constellations

Utilizing GNSS signals 

broadcasted by more than one 

GNSS constellation (e.g. GPS 

built by the U.S., GLONASS 

built by Russia, DBS built by 

China, Galileo built by the 

European Union) to solve 

positioning calculations.

 Impacts to GNSS signals tend to be more “local” so if satellite 

signals are used, the impacted signal will have less weight in the 

GNSS solution.

 Less likely for receivers to lose lock since more satellites can be 

seen at any one time.

Augmentation 

Systems

Supplemental systems external 

to GNSS systems that provide 

additional data to GNSS users to 

improve quality of GNSS 

service. Systems can be ground 

or space based and can provide 

a variety of data, for example, 

GNSS error information and 

corrections. 

 Ground based augmentation services are more local in nature. 

They also tend to be resource intensive to operate and maintain so 

some are starting to be decommissioned. 

 Satellite based augmentation services are more expensive but 

provide regional coverage (e.g. the Wide Area Augmentation 

System (WAAS) in U.S. and the European Geostationary 

Navigation Overlay Service (EGNOS) in Europe). They can also 

be affected by space weather (e.g. December 2006) but unclear 

extent to which it may compromise operations. 

 Corrections sent by satellites can be interrupted for ~5-10 minutes 

but this can be addressed by increasing the holdover capacity of 

receivers. 

Mitigating 

Actions

Differential 

Correction

Decision made to post-process 

GNSS data to increase its 

accuracy by comparing 

measurements taken by more 

than one GNSS receiver. 

 Theoretically possible, but not clear if or under what 

circumstances this may be done. Users typically worried about 

having highly-accurate information to inform the appropriate 

Defensive Investments. 

 Any automatic, real-time applications of this are covered in our 

Defensive Investment category (e.g. Receiver Design & 

Engineering). 

Schedule 

Changes

In anticipation of possible 

service degradation and/or 

service outages, GNSS users 

may decide to change timing of 

operations that may be sensitive 

to potential problems. 

 Decision hinges on how costly schedule changes are to end users 

and may rarely occur, especially if costs are high (e.g. off-shore 

drilling). 

 Some third-party GNSS service providers offer their own 

forecasts of anticipated disruptions to end users to make them 

aware of risks. 

Service 

Interruptions

Quality 

Degradation

Any reductions in the quality of 

information provided by the 

standard GNSS service. 

 There are many different ways to think about the “quality” of 

GNSS service (e.g. availability, accuracy, continuity, integrity).

 Quality needs and therefore impacts from quality vary 

dramatically from user to user. 

Outage 

Inability of GNSS user to 

receive usable PNT information 

from GNSS satellites. 

 Impact occurs most frequently in high-latitudes and equatorial 

region. 

 Uncertain if it has been observed in mid-latitudes regions but this 

could certainly happen during an extreme event.
46

5.3 Cost Estimates

In order to translate our findings into quantitative cost estimates that capture the most concerning and potentially 

largest impacts, we conducted a second round of stakeholder outreach. Although this additional input helped us quantify 

the potential impacts from Service Interruptions (~$4 million to ~$8 million for the moderate event scenario and ~$100 

million to ~$600 million for the extreme event scenario), we received much less guidance from our stakeholders on this 

sector compared to others. The input gained from our additional outreach is nonetheless provided below alongside a 

description of how it influenced the derivation of our cost estimates. Note that our estimate are conservative since they 

only capture how GNSS outages may reduce the economic benefits provided by GNSS to a sub-set of applications where 

there has been a relative large penetration of the technology. Although the potential costs would certainly be much 

higher if we included other types of impacts from GNSS outages (e.g. health and safety, environment, etc.), we were 

unable to find adequate information on these topics to propose defensible estimates [Leveson, 2015a]. Our cost estimates 

are also preliminary and rely upon an early quantitative analysis of this topic and data from 2013 [Leveson, 2015a]. 

There was not enough publically available information on this study to be able to use updated and current numbers for 

2016. Given the rapid increase in GNSS usage in the intervening years, impacts estimated herein may therefore be 

understated. 

Table 20. Simplified GNSS impact matrix, with the focus of our cost estimate highlighted in yellow. The presence 

(or absence) of a circle denotes where we were able to connect a given physical effect to a particular impact category 

during our first round of stakeholder outreach (see Table 17 for a list of items represented by each circle). Closed 

circles denote that the physical effect is known, from direct past experience, to cause impacts of that particular 

category. Open circles indicate that the physical effect may cause that particular type of impact but the linkage 

presently lacks empirical support.

Physical Effects

Impact Categories

Defensive 

Investments

Mitigating 

Actions

Asset 

Damages

Service 

Interruptions

Health

Effects

Ranging Errors ● ○ ●

Loss of Lock ● ○ ●

5.3.1 Service Interruptions 

We estimate that a moderate event may cost GNSS users ~$4 to ~$8 million (Table 21) whereas a more extreme 

event may cost ~$100 million to $600 million (Table 22). Our stakeholders emphasized that the potential impacts from 

a GNSS Service Interruption varies as widely and changes as rapidly as GNSS use itself. Our cost estimate therefore 

builds off a recent study that quantifies the benefits of GNSS (GPS) to the U.S. [Levenson et al., 2015a; 2015b]. We 

assume that a moderate and extreme space weather event both lead to a GNSS outage that imposes costs to end users by 

reducing these economic benefits. Note that GNSS provides additional, non-market benefits (e.g. health and safety, 

environment) that we were unable to capture due to insufficient quantitative information of this topic [Leveson et al.,

2015]. We were also unable to find enough information to capture any societal costs resulting from potential impacts to 

our nation’s critical infrastructure (e.g. chemical, communications, energy, financial services, informational technology, 

water and waste water, etc.) (for the complete list of 16, as defined by the Department of Homeland Security (DHS), see 
47

Table 23). Our cost estimates are therefore incomplete and should be updated when such pertinent information becomes 

available. At present, our numbers should therefore be interpreted as conservative estimates of potential costs. 

5.3.1.a. Moderate Event Scenario 

We estimate that a moderate space weather event may cost end users of GNSS in the U.S. ~$4 to ~$8 million. 

This estimate captures the costs of an event that is able to cause a ~1 hour GNSS outage across the U.S. and that impacts 

different types of end users to various degrees. It is based on a historic consideration of past events that have impacted 

GNSS users, important differences between users in their susceptibilities to an event, and the economic benefits of GNSS 

to a representative set of applications. 

Our first step involved considering past historic space weather events in order to develop a moderate scenario 

for the duration and extent of the GNSS signal disruption. Stakeholders pointed us to the Halloween storm in 2003 and 

the December 2006 event as key events with notable impacts to GNSS users. Although we located a number of detailed 

scientific analyses of these events [e.g. Chen et al., 2005; Cerruti et al., 2006; Cerruti et al., 2008], we found limited 

and anecdotal documentation about their actual impacts. During the 2003 Halloween storm, for example, one report 

states that surveying activities on land, in the air, and at sea were delayed and drilling operations were either postponed 

or cancelled [e.g. NOAA, 2004]. Although our stakeholders provided order of magnitude cost estimates of these impacts 

of ~$10,000 to ~$100,000 per day, it is unclear how long these delays and cancellations lasted and how widespread they 

were (or could be). We therefore reviewed the more detailed scientific analyses of these events to develop a GNSS 

outage scenario for our moderate event. Specifically, during the 2003 Halloween Storm, a series of solar radio bursts 

caused GNSS receivers worldwide to intermittently lose lock for periods of time from minutes [Chen et al., 2005] up to 

hours [Astafyeva et al., 2014]. Airlines were also unable to use the Federal Aviation Administration’s (FAA) Wide Area 

Augmentation System (WAAS) for precision approaches for a total of ~25 hours over two days during the Halloween 

2003 storm (e.g. for ~15 hours on October 29 and ~11 hours on October 30) [e.g. NOAA, 2004; Doherty et al., 2004]. 

We were unable to determine, however, if this ~1 day long interruption caused substantive impacts (e.g. flights were 

delayed) or if it was more of a nuisance (e.g. pilots reverted to alternate landing procedures). During the December 2006 

event, GNSS receivers on the sunlit side of the Earth were disrupted for tens of minutes [Cerruti et al., 2008] up to ~1 

hour [e.g. Carrano et al., 2009]. Similar to the Halloween 2003 storm, however, we found limited documentation on 

how this event in turn impacted GNSS users. To reflect these historical observations, our moderate scenario therefore 

envisions a space weather event that disrupts GNSS signals across the entire U.S. for ~1 hour. Note that this assumes 

that the GNSS service ceases and resumes with the space weather disruption. Moreover, it seems as if we have not 

experienced a “moderate” storm that has significantly impacts GNSS users since the U.S. made GNSS [Global 

Positioning Service (GPS)] freely available in 2000. It is therefore hard to establish potential impact thresholds if we 

have not yet experienced significant impacts.

Our next step was to determine what percentage of GNSS users within the U.S. may incur an outage as a result 

of this disruption. Stakeholders emphasized that the susceptibility of different GNSS users to any given space weather 

event varies dramatically from user-to-user and for a given user, from location-to-location. There are at least nine types 

of GNSS applications at present with substantial economic benefits including precision agriculture, construction, 

surveying, transportation (including air, rail, maritime, and road), timing, and consumer location-based services (LBS) 
48

[Levenson, 2015a]. Although each of these applications is comprised of a diverse GNSS user base, it is possible to make 

some generalization about typical users susceptibilities within each application. We classified users within each of these 

applications as having either low, medium, or high quality GNSS service needs by reviewing key GNSS performance 

parameters listed for different GNSS market receivers [European GNSS Agency, 2016]. These parameters include 

accuracy, availability, continuity, integrity, robustness, continuity, indoor penetration, time to first fix, latency, and 

power consumption [see Annex I in European GNSS Agency, 2016]. We used accuracy and continuity as our quality 

indicators since they most directly correspond to the effects of space weather on the GNSS signal (Table 18). 

Specifically, ranging errors and loss of lock can both degrade accuracy whereas loss of lock can interfere with continuity. 

We then mapped our nine different types of GNSS applications of focus to their mass markets and noted whether user 

priorities for both accuracy and continuity are either lower or higher (Table 21). Recall that our stakeholders also 

reported a large range in GNSS receiver price and quality, from ~$10 to more than ~$100,000 per receiver. To reflect 

the fact that users needing different quality services generally purchase receivers of different qualities that will vary in 

their susceptibilities to a given disturbance, we assume that the disruption occurring in our moderate event scenario 

causes as outage impacted ~100% of users with the low quality GNSS needs, 10% of users with medium quality GNSS 

needs, and 1% of users with high quality GNSS needs (e.g. users with lower quality needs purchase less expensive 

receivers that are more vulnerable to events whereas those with higher quality needs purchase more expensive receivers 

that are less vulnerable to disruptions).

Our final step is to compute the costs of this outage scenario to different GNSS applications. Levenson et al.,

[2015a] estimate that the economic benefit of GNSS enabled technologies across these nine different applications may 

total ~$37.1 to ~$74.5 billion per year (Table 21). We assume that our moderate event imposes costs to these GNSS 

users by reducing these total annual benefits by an amount that is proportional to the length of the outage (~1 hour) and 

the percentage of application users within the U.S. that are impacted. Our calculations assume that the event happens 

during working hours and these benefits, and therefore costs, accrue during the eight hour working day rather than over 

a full 24 hour day. Summing our results across all applications suggests a cost to these applications that varies by 

multiple orders of magnitude but may collectively total ~$4 to $8 million, with largest costs (~$3 to $6 million) for mass 

market users of GNSS enabled Consumer Location Based Services (for additional details, see Table 21). Note that this 

approach ignores the potentially important insight that some of these applications may be able to absorb a ~1 hour 

disruption without being impacted by it. Certain applications may be impacted by GNSS outages of any non-zero 

duration whereas other may not be impacted until it exceeds some threshold length. It is unclear, for example, if a ~1 

hour outage would or would not reduce the annual economic benefits of GNSS across all of these applications (e.g. a ~1 

hour outage that results in a delay for air transportation may prove large whereas the same ~1 hour outage that results in 

a delay of fertilizing, watering, or seeding for precision agriculture may be inconsequential). We were unable to find 

enough information about this topic to incorporate this potentially important point into our current cost estimate. As 

mentioned in the beginning of this section, this approach produces a conservative estimate of the potential economic 

impact of the event since it only captures how an outages may reduce the economic benefits provided by GNSS to a subset of applications where there is enough information to quantify and there has been a relative large penetration of the 

technology. It is furthermore conservative because it is built off a study that assesses only a subset of users within each 

application (e.g. estimate of precision agriculture only considers benefits to grain farming). Although the costs may be 
49

much higher if we include other types of impacts from GNSS outages (e.g. health and safety, environment, etc.), we 

were unable to find enough information on these topics to propose defensible numbers. 

Table 21. Cost estimates reflecting a GNSS outage, as envisioned in our moderate event scenario, that lasts ~1 hour 

and impacts a broad spectrum but different percentage of GNSS users across the U.S.

GNSS 

Application1

Receiver 

Market2

User Priorities2

Quality 

Needs3

% of Users 

with 

Outage4

Range of 

Benefits

(Billions/yr)1

Estimated Costs

Accuracy Continuity

To 

Application

To 

Market

Consumer 

LocationBased 

Services

Mass Market Low Low Low 100% $7.3-18.9 $3-6 m $3-6 m

Timing

High 

precision, 

timing & 

asset

management 

solutions

High Low

Medium

10%

$0.025-0.050 $900-2000

$1-2 m

Precision 

Agriculture High Low $10-17.7 $0.3-0.6 m

Surveying High Low $9.8-13.4 $0.3-0.5 m

Construction High Low $2.2-7.7 $0.08-0.3 m

Fleet Vehicle 

Telematics High Low $7.6-16.3 $0.3-0.6 m

Maritime 

Transport

Transport & 

Safety 

Liability 

Critical 

Solutions

High High

High

1% $0.106-0.263 $400-900

$800-

2000 Air Transport High High $0.119-0.168 $400-$600

Rail 

Transport High High $0.010-0.100 $30-$300

Total $37.1-74.5 ~$4-8 m

1

Information provided in Leveson, 2015a unless otherwise noted. Annual benefits represent mid-range values. 

2

Information derived from GNSS User Technology Report [European GNSS Agency, 2016], which describes different 

GNSS receiver markets and identifies their user priorities in terms of key performance parameters. Here, these three 

mass markets are mapped to different applications [Leveson, 2015a] and note whether the most relevant performance 

parameters for space weather impacts, accuracy and continuity, are of high or low priority to these users. For 

information on Mass Markets see p. 31, on Transportation & Safety Liability Critical Solutions see p. 40, and on High 

Precision, Timing & Asset Management Solutions see p.53. 

3Applications where users have accuracy/continuity needs that are low/low, high/low, and high/high are assumed to 

need low, medium, and high quality GNSS services respectively. 

4Stakeholders reported a large range in GNSS receiver price and quality, from ~$10 to ~$100,000 per receiver. To 

reflect the fact that users needing different quality services generally purchase receivers of different qualities that will 

vary in their susceptibilities to a given disturbance, we assume that the event causes an outage to 100%, 10%, and 1% 

of users with low, medium, and high service quality needs respectively. 

5.3.1.b. More Extreme Event Scenario 

Under more extreme conditions, we estimate space weather impacts that could cost GNSS users within the U.S. 

~$100 million to ~$600 million. Our extreme scenario follows the methodology outlined for our moderate event scenario 

but assumes that the outage will instead last for ~1-3 days [Cannon et al., 2013; Hapgood et al., 2016] and impacts an 

order of magnitude more users than in our moderate event scenario (Table 1). 

Table 22. Cost estimates reflecting a GNSS outage, as envisioned in for the extreme event scenario, that lasts ~1-3 days 

and impacts a broad spectrum but different percentage of GNSS users across the U.S.

GNSS 

Application

Receiver 

Market

Quality 

Needs

% of Users 

with Outage

Range of Benefits

(Billions/yr)

Estimated Costs

To Application To Market
50

Consumer 

Location-Based 

Services

Mass Market Low 100% $7.3-18.9 $20-200 m $20-200 m

Timing

High 

Precision, 

Timing & 

Asset

Management 

Solutions

Medium 100%

$0.025-0.050 $0.07-0.4 m

$80-500 m

Precision 

Agriculture $10-17.7 $30-100 m

Surveying $9.8-13.4 $30-100 m

Construction $2.2-7.7 $6-60 m

Fleet Vehicle 

Telematics $7.6-16.3 $20-100 m

Maritime 

Transport

Transport & 

Safety 

Liability 

Critical 

Solutions

High 10%

$0.106-0.263 $0.03-0.2 m

Air Transport $0.119-0.168 $0.02-0.1 m $0.06-$0.4 m

Rail Transport $0.010-0.100 $3,000-$80,000 

Total ~$100-600 m

In addition to being a conservative estimate for all previously mentioned reasons, note that GNSS enabled 

technologies are becoming more and more integral to our nation’s Critical Infrastructure [e.g. Caverly, 2011]. For 

example, we found a preliminary report stating that 11 out of 16 components of our nation’s Critical Infrastructure were, 

as of 2011, reliant upon GNSS technologies (Table 23) (e.g. internal systems that allow them to run for a specific length 

of time without GNSS) [e.g. Caverly, 2011]. However, we were unable to find information describing these 

dependencies in sufficient detail to analyze potential impacts of an event. Note that this report also provides information

of different holdover capacities (e.g. internal systems that allow them to run for a specific length of time without GNSS), 

which are all commensurate in length with the low-end of our outage duration (~1 day) and smaller than our high-end 

(~3 days). Although this suggests the potential for societal impacts, we were unable to find more information on how 

these holdover capacities may have changed over the last 6 years [i.e. since Caverly, 2011]. SWAP efforts to establish 

benchmark GNSS outage scenarios are not yet complete [Executive Office of the President, 2017] but will be followed 

by a comprehensive vulnerability assessment of our nation’s Critical Infrastructure to such benchmarks [Space Weather 

Action Plan, 2015]. While there is not currently enough information to assess the impacts of potential GNSS outages 

via effects on Critical Infrastructure, it will be important to estimate the costs when these other studies conclude and in 

light of their light findings.

Table 23. U.S. Critical Infrastructure is reliant on GNSS technologies so the potential societal impacts of an 

extreme event on the U.S. may be large but is currently unknown. 
51

Critical Infrastructure (CI) Sector1 Reliant on GNSS2? Holdover Capacity

(Hours)2

Chemical Yes 1

Commercial Facilities

Communications Yes 24+

Critical Manufacturing Yes 1.7

Dams Yes 1

Defense Industrial Base Yes 1.7

Emergency Services Yes 24+

Energy Yes 1

Financial Services Yes <0.24-1.7

Food and Agriculture

Government Facilities

Healthcare and Public Health

Information Technology Yes 1

Nuclear Sector Yes 1

Transportation Systems Yes 24+

Water and Wastewater Systems

1https://www.dhs.gov/critical-infrastructure-sectors 

2Assessment of reliance is based on sectors where GNSS timing information was identified by DHS as essential (Caverly, 

2011)

3

In order to determine if a Critical Infrastructure (CI) sector is impacted by a moderate and extreme event, the sector must (1) 

be reliant on GNSS and (2) the outage duration for the moderate (1 hour) and extreme (1 day) space weather scenarios must be 

greater than the sector’s holdover capacity. 

5.4 GNSS References 

Astafyeva, E, Yu. Yasyukevich, A. Maksikov, and I. Zhivetiev. 2014. Geomagnetic storms, super-storms, and their 

impacts on GPS-based navigation systems. Space Weather. Volume 12, Issue 7. Pages 508-525.

Baker, D.N. and L.J. Lanzerotti. 2016. Resource Letter SW1: Space Weather. American Journal of Physics. Vol. 

84, No. 3.

Cannon, P.; Angling, M., Barclay, L., Curry, C., Dyer, C., Edwards, R., et al., 2013. Extreme space weather: impacts 

on engineered systems and infrastructure, UK Royal Academy of Engineering, London, ISBN 1-903496-95-0.

Caverly, J.R. 2011 GPS Critical Infrastructure (Usage/Loss Impacts/Backups/Mitigation). Space Weather Workshop. 

Boulder Colorado. April 26-29. April 27, 2011. 

Cerruti, Alessandro P., Paul M. Kintner, Dale E. Gary, Louis J. Lanzerotti, Eurico R. de Paula, and Hien B. Vo. 2006. 

Observed solar radio burst effects on GPS/Wide Area Augmentation System carrier-to-noise ratio. Space 

Weather. Volume 4, Issue 10.

Cerruti, Alessandro P., Paul M. Kintner Jr., Dale E. Gary, Anthony J. Mannucci, Robert F. Meyer, Patricia Doherty, 

and Anthea J, Coster. 2008. Effect of intense December 2006 solar radio bursts on GPS receivers. Space 

Weather. Volume 6, Issue 10. doi:10.1029/2007SW000375.

Chen, Z., Y. Gao, and Z. Liu (2005), Evaluation of solar radio bursts’ effect on GPS receiver signal tracking within 

International GPS Service network, Radio Sci., 40, RS3012, doi:10.1029/2004RS003066.

Doherty, P., A.J. Coster, and W. Murtagh. 2004. Space weather effects of October-November 2003.” GPS Solutions. 

Vol. 8, Issue 4. P. 267-271. Doi:10.1007/s10291-004-0109-3

European GNSS Agency, GNSS User Technology Report, Issue 1, copyright c 2016

Hernández-Pajares, M., J. M. Juan, J. Sanz, À. Aragón-Àngel, A. García-Rigo, D. Salazar, and M. Escudero 
52

(2011), The ionosphere: effects, GPS modeling and the benefits for space geodetic techniques, JGeod, doi: 

10.1007/s00190-011-0508-5.

Kintner, P. M., B. M. Ledvina, and E. R. de Paula (2007), GPS and ionospheric scintillations, Space Weather, 5, 

S09003, doi:10.1029/2006SW000260.

Leveson, I., 2015a. The Economic Benefits of GPS. GPS World. September 2015. 

Leveson, I., 2015b. The Economic Value of GPS: Preliminary Assessment. National Space-Based Positioning, 

Navigation and Timing Advisory Board Meeting, June 11, 2015. Downloaded from: 

http://www.gps.gov/governance/advisory/meetings/2015-06/leveson.pdf 

National Oceanic and Atmospheric Agency (NOAA). 2004. Service Assessment: Intense Space Weather Storms 

October 19-November 7, 2003.

Tsurutani, B. T., O. P. Verkhoglyadova, A. J. Mannucci, G. S. Lakhina, G. Li, and G. P. Zank (2009), A brief review 

of ‘‘solar flare effects’’ on the ionosphere, Radio Sci., 44, RS0A17, doi:10.1029/2008RS004029.
53

6. Aviation 

6.1 Impact Mechanisms

During space weather events, increases in both electromagnetic and particulate radiation may affect aviation in 

various ways [Jones et al., 2005; Cannon et al., 2013; Baker and Lanzerotti, 2016]. Increases in electromagnetic 

radiation may diminish the capabilities of various aircraft communication and navigation systems that are fundamental 

to airplane operations. This may occur, for example, if the ionosphere becomes highly ionized and attenuates rather than 

reflects the High Frequency (HF) radio waves that airborne planes use to send and receive critical information. 

Communication and navigation capacities may similarly be diminished when electromagnetic radiation from a space 

weather event introduces sufficient noise to significant lower signal-to-noise ratios [Jones et al., 2005; Cannon et al.,

2013; Baker and Lanzerotti, 2016]. Effects may also result from enhanced levels of particulate radiation given its ability 

to penetrate matter and deposit energy. Neutrons, for example, are thought to be particularly effective at penetrating and 

depositing energy inside the silicon microchips that control a growing number of airplane electronic (“avionic”) 

equipment. Such effects involve an individual incident neutron and are therefore referred to as Single Event Upsets 

(SEUs) or avionic upsets [Dyer et al., 2000; Normand, 2001; Campbell et al., 2002; Dyer, 2002]. SEUs may cause 

either soft or hard errors such as bit flips or circuit latch-ups and burn-outs. Particulate radiation can also penetrate 

human cells and may directly break down deoxyribonucleic acid (DNA) strands in tissue or produce free radicles in 

biological tissues that may alter cellular functions. Space weather is therefore also potentially hazardous to those onboard

aircraft where potential radiation exposure at high dose rates received at airplane altitudes may be significant [Butikofer 

et al., 2008; Dyer et al., 2003; Langtos and Fuller, 2003; Getley et al., 2005; Getley et al., 2010], potentially leading to 

adverse health outcomes such as increases in the risk of cancer and lower cognitive ability of unborn fetuses.
54

Figure 8. Impact mechanism diagram for aviation outlining the primary causal pathways from a solar event to physical 

effects (grey boxes) that can in turn cause a variety of social and economic impacts (green boxes). Note that our 

illustration depicted is not to scale, not comprehensive, and should be revised with future input from stakeholders to 

ensure it captures largest potential concerns. 

6.2 Stakeholder Perspectives on Impacts

Our first phase of stakeholder outreach involved hour long phone calls with 6 individuals with expertise on 

space weather and aviation. We used our impact matrix to guide these conversations and to systematically collect input 

on the known physical effects of space weather on aviation and the types of impacts that each may cause. Our final 

impact matrix is presented below (Table 24) along with additional and important insights from these conversations, 

including definitions and notes on the various physical effects (Table 25) and impacts (Table 26). The remainder of this 

section provides a high-level overview of what we learned from these stakeholder discussions.

Depending on roles and responsibilities, industry stakeholders emphasized different concerns about the known 

physical effects of space weather on aviation (Table 25). Airplane manufactures, for example, were most concerned 

about safeguarding airplane electronics (“avionics”) against Single Event Upsets (SEUs). Although critical avionic 

equipment and circuits are rigorously designed and tested to minimize the potential problems that SEUs can cause, they 

explained how this hazard is continuously evolving in complexity alongside other industry trends such as the increasing 
55

dependence on aircraft computers, shrinking chip sizes, and increasing flight altitudes. Airplane operators on the other 

hand were primarily concerned about space weather’s potential to disrupt different communication technologies, 

especially High Frequency (HF) radio which to date remains an important mode of communication especially along 

polar and oceanic routes. Many stakeholders noted that the nature of this effect may change in the future, as satellite 

communication technology which has different vulnerabilities to space weather (e.g. see Link Disruptions in the Satellite 

section) is increasingly adopted across the industry. Stakeholders working more directly on a range of aircraft safety 

issues expressed unknown but potentially growing risks from the increasing role of GNSS in airplane navigation 

combined with the decommissioning of ground based navigation aids around the world. And lastly pilots, flight 

attendants, and representatives throughout the industry also expressed concerns about exposure to enhanced level of 

radiation that could occur if flying at altitude during a space weather event. 

Stakeholders were able to readily populate our impact matrix with many examples across the different impact 

categories (Table 26). Stakeholders spoke at length about the substantial number of Defensive Investments made across 

the industry that protect against the impacts of space weather events but also stressed that such investments are made to 

ensure and enhance the safety and efficiency of airplane services against all-hazards (e.g. terrestrial weather, bird strikes, 

terrorists, etc.). Stakeholders with experience working in polar-regions were most familiar with space weather and noted 

that potential disruptions to HF radio often prevent airlines from flying planned schedules or routes since the inability of 

an aircraft to be in continuous contact with Air Traffic Control (ATC) violates Federal Aviation Administration (FAA) 

law. Although rerouting airplanes around regions where HF radio may be disrupted can be considered an effective 

Mitigating Action, stakeholders noted that it tends to be costly to airlines in terms of additional fuel, reduced cargo, 

landing fees, and employee workloads. They also reported a drop in the number of occasions of this occurring in the 

recent past, due to the relatively calm recent solar conditions. Depending on the circumstances, airlines may also opt to 

delay or cancel flights depending on where and how long the disturbance lasts. Although infrequently enacted for space 

weather reasons, all Mitigating Actions are a routine part of the business and are frequently enacted for a variety of 

reasons and directly cause Service Interruptions for passengers who will then arrive late at their destinations. Although 

many stakeholders were concerned about potential Health Effects, they stressed that the scientific connection between 

radiation exposure and health outcomes (e.g. cancer) remain heavily debated and largely uncertain. Many airlines 

nonetheless take simple precautionary actions such as temporarily lowering cruising altitude if it does not jeopardize 

aircraft safety for other reasons (e.g. surrounding airspace is uncrowded and sufficient fuel is aboard to compensate for 

decreased fuel efficiency). 
56

Table 24. Impact matrix populated during stakeholder outreach to better understand how the known physical effects of space weather (Table 25) on 

aviation can cause different types of impacts. Items in the matrix reflect example impacts and stakeholder perspectives on the differences between 

impacts that might occur during moderate (normal text) compared to more extreme (italic text) space weather conditions. Question marks denote 

instances where the physical effect may in theory be able to cause this impact but empirical support is lacking. *Additional details pertaining to a 

select set of these impacts can be found in Table 26. 

Physical Effects

Impact Categories

Defensive Investments Mitigating Actions Asset Damage Service 

Interruptions Health Effects

Communication

•Personnel training

•Maintenance of 

alternative procedures*

•Redundant technologies*

•Situational Awareness

•Preflight planning

•Aircraft 

schedule/route 

changes*

•Accidents?* •Delays*

Navigation

•Personnel training

•Maintenance of 

alternative procedures*

•Redundant technologies*

•Augmentation systems

•Alternative 

procedures •Accidents?* •Delays*

Avionic Upsets 

(SEUs)

•Design & Engineering

•Avionic testing 

•Redundant technologies*

•Equipment 

inspections

•Alternative 

procedures

•Equipment 

failure 

•Accidents?* 

Effective Dose •Situation awareness

•Inflight measurements 

•Preflight planning

•Reduce altitude

•Post-event analysis

•Aircrew schedule 

changes

•Delays*

•Cancer*

•Lower Cognitive 

Ability*
57

Table 25. Definitions of key effects of space weather on aviation that includes notes from stakeholder interviews on 

current status and future of each specific impact. 

Physical 

Effects Definition Notes from Stakeholder Outreach

Communication Any degradation or 

interruption in the signal used 

to transmit information 

to/from an aircraft and 

therefore can potentially cause 

the degradation or disruption 

of communication systems. 

• Most frequently a problem for routes still reliant on High-Frequency (HF) radio 

(e.g. polar, high-latitude, and oceanic). These routes are also some of the most 

profitable in an industry with small margins. 

• Importance of effects in the polar region is relatively recent, starting after Russian 

airspace opened in 2001 and after long-haul aircraft with sufficient ranges were 

built. 

• Communication problems could decrease in future if more airlines move away 

from HF radio to usage of satellite communications. Currently, these services (e.g. 

IRIDIUM or INMARSAT) are proving beneficial. 

• Communication problems could also decrease if industry adopts technologies with 

Ka-frequencies. Ka-frequencies are not currently utilized due to problems with 

rain fade but the industry is actively working to overcome issues due to their higher 

bandwidths. 

• Potential decreases could be offset by increase in air travel. Impacts in future could 

still increase if a larger number of airplanes/people are impacted by an event. 

Navigation Any degradation or 

interruption in the signal used 

to transmit information 

to/from an aircraft that can 

potentially cause the 

degradation or disruption, or 

failure of navigation systems.

• A number of navigation systems utilized by an airline can be impacted (e.g. Radar, 

Satcom) but main concern is interruption to GPS-based navigation (e.g. WAAS). 

• Impact largely unknown due to recent increase in GNSS over recent years. It may 

cause a real problem or just be nuisance creating more workload for pilots. 

• Although less frequently observed in mid-latitude areas, problems have most 

potential to be problematic here given the higher volume and density of air traffic. 

Navigation problems only apply to approaches/landings and may be growing issue 

due to decommissioning of ground based navigation aids. 

Avionic Upsets 

(SEUs)

A random, non-permanent 

soft error in the digital 

systems that are the 

foundation of airplane 

electronic (“avionic”) 

equipment. 

• SEUs are a well-studied and understood phenomenon that engineers expect to 

happen and therefore design accordingly (e.g. radiation hardened microchips, 

voting systems in circuits, and error detection/correction software).

• SEUs have potential to cause problems in digital electronics but infrequently do.

• The more critical a system is, the more engineering goes into it. Avionic equipment 

must surpass tight standards and often undergo testing and accreditation by third 

parties to ensure the integrity of their performance at inflight conditions. Unclear 

the degree to which space weather events are addressed by industry design 

standards. 

• Problem is likely to increase in future due to technological trends including 

increased usage of electronics, the miniaturization of silicon chips, and use of 

commercial off-the-shelf technologies. 

• SEUs are also caused by internal processes (e.g. interconnect coupling) so 

determining precise cause of any given SEU is hard. 

• Cabin equipment manufacturers are starting to put time and effort into SEUs 

because glitches in performance of entertainment equipment can degrade airline 

brand. 

Effective Dose Absorbed ionizing radiation 

dose weighted for the radiosensitivity of each organ and 

the type/energy of radiation. 

• Largest exposure in polar/high-latitude regions and on long haul flights. 

• Very sensitive topic, empirical evidence linking exposure to effects is lacking. 

Uncertainties lead to wide variety of responses within industry. 

• Stewardesses and pilots have mixed concerns, caring about potential health issues 

but also potential loss of work (e.g. restricted hours or early retirement) if 

regulations were established. 

• Problem is likely to remain and be key concern in future since, unlike other 

impacts, there is no foreseeable technological fix (e.g. shielding thickness required 

would be uneconomical). 

• Unlikely that the scientific uncertainties will be resolved in near future. Certain 

airlines nonetheless take issue serious even though there are no regulations in place 

about annual dose limits. 

• Exposure levels may increase in future if airlines continue trend of offering longer 

and higher altitude flights. On the other hand, exposure levels may decrease if 

more airlines start considering exposure in route and schedule planning for flights 

or key personnel (e.g. pilots, stewardesses). 
58

Table 26. Additional details on a select set of space weather impacts in our impact matrix (Table 10) identified 

during stakeholder outreach. 

Impact 

Category Examples Definition Notes from Stakeholder Outreach

Defensive 

Investments

Maintenance 

of alternative 

procedures

Retaining the capacity for 

a range of alternative 

procedures (e.g. nonprecision approaches) 

under sub-optimal 

operating conditions 

requires infrastructure, 

published information 

(e.g. book, maps, etc.), 

and trained personnel. 

Very expensive but invested in due to range of hazards faced by industry. 

Space weather events are more likely to change take-off and landing 

procedures rather than inflight procedures. 

Key personnel are trained to follow specific procedures if a given 

condition arises. Although helpful against potential problems caused by 

single event effects, tends to be more relevant for 

communication/navigation problems. For example, fall back on 

traditional navigation aids if space weather renders GNSS navigation 

unavailable. On an event-by-event basis, the additional workload for 

personnel may be more of a nuisance than costly. 

Redundant 

technologies

Airlines are required by 

law to have multiple 

systems that can be used 

to maintain continuous 

communication and 

navigation capabilities. 

Very expensive but invested in due to range of hazards faced by industry 

and fundamental importance of safety. 

Capabilities of redundant (e.g. backup) technologies are still very high and 

automatically enacted so their utilization is typically seamless. 

Mitigating 

Actions

Aircraft 

schedule and 

route changes

Deciding to delay an 

aircraft from taking off or 

to fly a different route 

than planned in 

anticipation or reaction to 

a space weather event. 

Most often a precautionary decision based on information provided by 

SWPC or other commercial providers. 

Delays are usually minor since many events tend to be short lived. 

Most common for polar routes and high-latitude routes where it may occur 

a couple to a handful of times per year. May happen more frequently in 

future as we transition from solar minimum to maximum. 

A variety of factors need to be considered and downstream logistics need 

to be coordinated. Economic consequences become non-linear if changes 

cause crew to run out of workable hours. 

Asset 

Damages Accidents

Any incident resulting in 

physical damage to an 

aircraft due to space 

weather. 

Could in theory happen due to physical effects (inability to communicate, 

failure of critical equipment, or erroneous positioning/navigation 

information). Not clear that this has ever happened to industry. 

Would be a hard to attribute to space weather, especially for moderate 

sized events. 

Service 

Interruptions Delays

Passengers on aircraft 

arrive late to destinations 

when airlines make 

various Mitigating 

Actions (e.g. delays, 

reroute changes) to reduce 

risk of space weather 

impacts.

Not clear how often it happens, especially outside polar-regions. 

Notable example was a relatively recent event in Sweden. Airspace was 

shut down since due to solar interference with radar systems. 

Costs increase quickly for rerouting if crew runs out of time and there are 

no replacements (e.g. in remote areas) 

Health 

Effects

Cancer

Increase in risk of cancer 

due to elevated exposure 

received while at airplane 

altitudes. Potentially 

relevant components of 

health cost include direct 

treatment costs (e.g., 

hospital bills), the costs of 

pain and suffering, the 

costs of lost life-years, 

and lost earnings.

Most relevant for those spending a lot of time in air (e.g. pilots, 

stewardesses, frequent flyers) or those in the air during a severe event. 

Now that internet services are offered in flight, informed passengers may 

access space weather alerts and advocate from cabin that pilots reduce 

altitudes. It is not clear how frequently this happens but it is a concern. 

Health concerns may not outweigh lost income concerns if limits were set 

(e.g. early retirement). 

Large uncertainties about actual exposure (e.g. not measured onboard 

aircraft but estimated/modeled) and linkages lead to diverse opinions. 

Could lead to class action lawsuits although not clear if currently 

happening for this reason. 

Lower 

Cognitive 

Ability

Increase in risk that 

unborn children in utero 

will have lower cognitive 

ability due to exposure 

received while at airplane 

altitudes. 

Large uncertainties about linkages lead to diverse opinions. 

Could lead to class action lawsuits although not clear if currently 

happening for this reason. 
59

6.3 Cost Estimates 

In order to translate our findings into quantitative cost estimates reflective of the most concerning and 

potentially largest impacts, we conducted a second round of stakeholder outreach. Most stakeholders suggested that we 

focus our quantification on impacts stemming from how space weather events affect High Frequency (HF) radio 

communication. This effect therefore underpins the costs estimates we developed for Mitigating Actions (~$400,000 to 

~$5 million for our moderate event scenario and ~$1 million to ~$30 million for our more extreme event scenario) and 

Service Interruptions (~$900,000 to ~$5 million for our moderate event scenario and ~$6 million to ~$200 million for 

our more extreme event scenario). The cost estimates for Mitigating Actions capture the costs of rerouting planes away 

from polar-regions during a moderate event and canceling flights in the continental U.S. under a more extreme scenario. 

Since these Mitigating Actions disrupt normal air traffic, our cost estimates of Service Interruptions therefore consider 

how these decisions in turn impact airline passengers in terms of their lost time. Although we examine the impacts 

stemming from potential disruptions to High Frequency (HF) Radio, note that this impact may decrease in the future as 

the industry continues to lessen its reliance on this communication technology. Key insights gleaned from our second 

round of stakeholder conversations are provided below alongside a description of how they influenced the derivation of 

our cost estimates. 

Table 27. Simplified aviation impact matrix with the focus of our cost estimates highlighted in yellow. The presence 

(or absence) of a circle denotes where we were able to connect a given physical effect to a particular impact category 

during our first round of stakeholder outreach (see Table 25 for a list of items represented by each circle). Closed 

circles denote that the physical effect is known, from direct past experience, to cause impacts of that particular 

category. Open circles indicate that the physical effect may cause that particular type of impact but the linkage 

presently lacks empirical support.

Physical Effects

Impact Categories

Defensive 

Investments

Mitigating 

Actions

Asset 

Damages

Service 

Interruptions

Health

Effects

Communication 

Degradation ● ● ○ ●

Navigation

Degradation ● ● ○ ○ ○

Human Exposure ● ○ ○

Avionic Upsets ● ○ ○ ○ ○

6.3.1. Mitigating Actions

We estimate that a moderate space weather event may cost the U.S. airlines ~$400,000 to ~$5 million, with a 

more extreme scenario that may cost ~$1 million to ~$30 million. Our estimates reflect how airlines are apt to respond 

to the potential loss of HF communication capabilities, and are therefore based on some initial assumptions about the 

duration and location of potential HF Radio disruptions. In our moderate scenario, a HF Radio outage in the polar-region 

causes operators to reroute their polar-flights for 1 day. The outage in our more extreme scenarios lasts for 1-3 days and 

results in the cancellation of ~1-10% of all domestic flights. Our stakeholders emphasized that rerouting or cancelling 

flights in anticipation or in reaction to an ongoing a space weather event are precautionary measures. They reduce the 
60

risk of more serious impacts that could in theory occur, for example accidents or collisions, if airplanes are unable to 

communicate important information with one another and/or with ground control. However, there is not enough 

information at this time to defensibly quantify the potential impacts that could results if such Mitigating Actions are not 

enacted. 

6.3.1.a. Moderate Event Scenario

We estimate that a moderate space weather event may cost U.S. airline operators ~$400,000 to ~$5 million. 

This estimate is based on a series of stakeholder discussions about moderate events, which are known to affect HF 

communications in polar-regions and therefore only impact airline carriers flying polar routes. According to polar 

operators, there is a standard industry response to moderate space weather events. When NOAA’s Space Weather 

Prediction Center issues a storm watch that is S3 or greater, they reroute all of their planned polar flights to lower 

latitudes. They further noted that the pre-flight decision-making process typically occurs in daily increments so it is 

appropriate to assume that an anticipated event will impact a full day of flights even if the HF disturbance created by a 

moderate event only lasts for a small fraction of a day. Our cost estimate outlined below therefore involves combining 

information on the costs of polar rerouting, the number of flights rerouted, and the percentage of polar flights operated 

by U.S. carriers. 

We need to first understand the costs associated with polar rerouting. The most widely cited figure for this 

Mitigating Action is ~$10,000 to $100,000 per flight [NOAA, 2004]. Although it in unclear where this estimate came 

from, our stakeholders were also somewhat uncertain about the actual costs involved. They reacted to this cited number 

favorably while noting that ~$100,000 is not typical but is reasonable as an upper limit. They further noted that the 

reported range captures the increased and variable costs of flying non-polar routes. Longer distances between 

destinations increases fuel consumption, travel time, and can often require additional stops plus landing fees for refueling 

and crew changes. This range is also consistent with reported costs savings of example polar flights (Table 28). One 

stakeholder noted that there are currently ~16 polar-routes, so this table includes a small sample of all polar routes flown 

by different airlines. We therefore assume the reported range for the costs of polar rerouting of ~$10,000 to $100,000 

per flight [NOAA, 2004]. 

Table 28. Example time and cost savings of polar routes for a set of example city pairs. 

City Pair1 Time Savings1 Cost Savings (Canadian $)1 Cost Savings (USD)2

Atlanta to Seoul 124 minutes $44,000 ~$41,000

Boston to Hong Kong 138 minutes $33,000 ~$31,000

Los Angeles to Bangkok 142 minutes $33,000 ~$31,000

New York to Singapore 209 minutes $44,000 ~$41,000

1Source: AMS, 2007

2Values converted to 2016 USD based on the mid-year 2004 currency conversion of 0.74605 USD per CAD 

(www.xe.com) and the U.S. BEA’s GDP price deflator value of 1.2505 to adjust from 2004 to 2016 (www.bea.gov). 

Our next step involved an assessment of the number of polar flights that would be rerouted. We were able to 

find a publically available document reporting that there were over 15,000 polar flights in 2015 [Nav Canada, 2016]. 

This suggests that a moderate event impacting polar operations for one day might result in the rerouting of ~41 flights 
61

(=~15,000 flights per year/365 days per year). Our stakeholders noted that polar air traffic is steadily increasing but that 

such information is not captured and cannot be derived from publically available flight data. The US Bureau of 

Transportation Statistics dataset, for example, only provides flight counts into and out of airports but does not provide 

information about the route that these planes took. Such information is logged, however, by different entities responsible 

for monitoring and controlling polar airspace. Stakeholders at the FAA and those affiliated with the Cross Polar Working 

Group were able to provide us with more recent and detailed polar flight statistics data by month. In 2016, there were a 

total of 15,815 polar flights with an average of 40.2-48 flights per day depending on the month (Table 29). Data available 

for 2017 suggests a slightly higher daily average that ranges from 44.6-50.4 flights per day. To capture the lower and 

higher end of these recent summary statistics, we simply assume that our moderate event involves the rerouting ~40-50 

flights (Table 29). One stakeholder further noted that ~100% of airlines operating polar routes remain reliant on HF 

communications (they are not equipped with polar satellite communications [e.g. IRIDIUM]) and that ~90% of all polar 

flights are operated by U.S. carriers. Combining all this information together, suggest rerouting costs to U.S. airlines 

that may be ~$0.4-$5 million (=$10,000-$100,000 per flight x 40.2-50.4 flights per day x 1 day x 0.90 U.S. flights). 

Our estimate does not consider the Southern Polar Region given the absence of U.S. carriers and the smaller 

volume of air traffic. We also do not consider the costs of rerouting flights away from High-Latitude Regions (e.g. those

along the North Atlantic Oceanic Track (NAT OTS) and the Pacific Oceanic Tracks [PACOTS]) since stakeholders note 

that polar flights constitute the vast majority (>95%) of space weather related rerouting.

Table 29. Statistics of polar flight numbers provided by a stakeholder. Note that these numbers are preliminary and 

should be critically reviewed and examined for consensus among the different entities that collect polar flight data.

2016 2017

Month Total Average Daily Total Average Daily

January 1,256 40.5 1,470 47.4

February 1,126 40.2 1,268 45.3

March 1,312 42.3 1,401 45.2

April 1,228 40.9 1,337 44.6

May 1,291 41.6 1,562 50.4

June 1,300 43.3 1,410 47.0

July 1,350 43.5

August 1,441 46.5

September 1,447 48.2

October 1,329 42.9

November 1,274 42.5

December 1,461 47.1

Yearly 15,815 40.2-48.2 44.6-50.4

 

6.3.1.b. More Extreme Event Scenario

Under more extreme conditions, we estimate that a space weather event may cost airline operators ~$1 million 

to ~$30 million. This estimate assumes disruptions to HF communications that are longer-lasting (e.g. ~1-3 days) and 

also more widespread, extending to lower-latitudes and impacting ~1-10% of all U.S. domestic flights. Our cost estimate 

also assumes flight cancellations, rather than rerouting as in our moderate scenario, and is therefore based on the number 

of cancelled flights and the average per flight costs of cancellations. 
62

In our extreme scenario, we assume disruptions to HF communications that are longer-lasting (~1-3 days) and 

that extend over a larger geographical area that encompasses the continental US. Airlines may therefore be unable to 

reroute flights around the disturbed area, as in our moderate scenario, and instead need to prevent flights from taking off 

until the event and the disturbance pattern it created within the atmosphere and ionosphere have both passed. We assume 

airlines cancel rather than delay flights because stakeholders note that the former is usually the less costly option, and 

therefore the preferred Mitigating Action, for more prolonged and more extensive air traffic interruptions as envisioned 

here. We furthermore assume that the outage only impacts ~1-10% of all U.S. domestic flights. This scenario 

assumption could be interpreted as the total portion of U.S. airspace that may be disturbed or else the percentage of 

airlines across the U.S. actually impacted by the disturbance which would depend, for example, on the backup 

communications onboard individual aircraft (e.g. Satellite communications) and their ability to perform under the 

disturbed conditions. In 2016, the average number of domestic flights in the U.S. was ~21,000-24,000 flights per day 

(Table 30). Note that we only consider domestic flights since we were unable to find a cost estimate that considers the 

cost of canceling international flights. This furthermore suggests that our final cost estimate may be conservative. An 

event that results in the cancellation of ~1-10% of domestic flights for ~1-3 days would therefore impact ~200-7,000 

flights (=0.01-0.10 x 1-3 days x 21,000-24,000 flights per day). According to a recent report, there is no generally 

accepted cost of cancellations for use in government cost-benefit studies but a reasonable estimate of the fixed cost to 

aircraft operators is ~$5,000 per flight cancellation [FAA, 2016]. This suggests that our extreme scenario might cost 

U.S. airlines ~$1 million to ~$30 million. 

 

Table 30. Monthly statistics describing U.S. Domestic air traffic in 2016.

2016

Month Total Number of 

Domestic Flight1 

Daily Average2 Total Number of 

Passengers1

Passengers per 

Flight3

January 636,907 ~21,000 52,474,764 ~80

February 612,287 ~21,000 51,112,202 ~80

March 697,968 ~23,000 61,593,910 ~90

April 675,765 ~23,000 58,894,484 ~90

May 702,507 ~23,000 62,751,668 ~90

June 713,120 ~24,000 64,757,139 ~90

July 730,481 ~24,000 66,133,058 ~90

August 731,594 ~24,000 63,497,082 ~90

September 672,886 ~22,000 58,618,920 ~90

October 688,246 ~22,000 61,709,276 ~90

November 658,300 ~22,000 59,270,072 ~90

December 662,304 ~21,000 59,178,742 ~90

Yearly 8,182,365 ~21,000-24,000 719,991,317 ~80-90

1Bureau of Transportation Statistics T-100 Segment data for All Carriers and All Airports. Available at: 

https://www.transtats.bts.gov/Data_Elements.aspx?Data=1 (flights and passenger data tabs) 

2Derived by dividing monthly BTS flights numbers by number of days in each month. 

3Derived by dividing monthly BTS flight numbers by monthly BTS passenger numbers. 

6.3.2. Service Interruptions 
63

In addition to imposing financial costs on the airline industry, space weather events may impact airline end 

users with estimated costs of ~$900,000 to ~$5 million and ~$6 million to ~$200 million for our moderate and extreme 

storm scenarios respectively. These cost estimates consider direct impacts to airline passengers who will be delayed 

because of airline Mitigating Actions, where impacts are assessed using the value of lost time [Department Of 

Transportation, 2016]. Note that there are other end users of airline services, for example, the shipping industry uses 

airlines to transport freight. There are also other upstream and downstream businesses dependent on airline transport 

that may be indirectly impacted by these disruptions in air traffic. Although such costs are also involved and important, 

such topics are beyond the scope of our current analysis.

6.3.2.a. Moderate Event Scenario

We estimate that our moderate event costs airline passengers ~$900,000 to ~$5 million. Recall that our 

moderate scenario assumes that airlines reroute ~40-50 polar flights (Table 29). Since lower-latitude routes are longer 

than polar routes, passengers scheduled to fly on these flights would therefore arrive late to their destinations. To derive 

a cost estimate, we therefore needed to establish the number of passengers impacted by the event, the amount of time 

they are delayed, and the costs per unit time of their delay. 

In order to understand how many passengers may be delayed, stakeholders noted that there are a limited number 

of aircraft models capable of flying polar-routes and include, for example, those manufactured by Airbus (e.g. models 

A340, A350, and A380) and by Boeing (e.g. models B744, B77, and B787). Publically available information on these 

specific aircraft models suggests that one polar flight may carry ~242-615 passengers (Table 31). This suggest that the 

event may delay ~10,000-30,000 passengers (= ~40.2-50.4 polar flights x ~242-615 passengers per polar flight). 

Table 31. Estimated number of passengers transported by various aircraft models flying polar routes.

Manufacturer Model # of Passengers

Airbus

A3401 250-475

A3502 280-366

A3803 489-615

Boeing

B7444 376

B7775 313-396

B7876 242-330

Range 242-615

1http://www.aircraft.airbus.com/aircraftfamilies/previous-generation-aircraft/a340family/

2http://www.aircraft.airbus.com/aircraftfamilies/passengeraircraft/a350xwbfamily/

3https://www.emirates.com/us/english/flying/our_fleet/emirates_a380/emirates_a380_specifications.aspx

4https://www.delta.com/content/www/en_US/traveling-with-us/airports-and5

aircraft/Aircraft/boeing-747-400-744.html

5http://www.boeing.com/commercial/777/#/design-highlights/characteristics/777-200er/

6http://www.boeing.com/commercial/787/by-design/#/787-10-characteristics

Our next step involved establishing the length of time that these passengers are delayed and the value of their 

lost time. We assumed that all passengers on these flights are delayed ~124-209 minutes, reflecting lower and upper 

bounds on the time savings associated with example polar routes (Table 28) [AMS, 2007]. Although this information is 

not a representative sample of all polar routes (i.e. 4 of ~16 routes as previously discussed), we were unable to obtain 

more precise information from the literature or via stakeholder discussions. We then noted the average value of this lost 

passenger time at ~$47.10 per person per lost hour (Department of Transportation, 2016). The estimate is also known 
64

as the Value of Travel Time Savings (VTTS) and values lost travel time for intercity flights at $36.10 per person per 

hour for personal travel and at $63.20 per person per hour for business trips. Noting a distribution between personal and 

business travel that is 59.6% to 40.4%, the weighted average value equates to ~$47.10 per person per lost hour (or $0.785 

per minute). Note that the vast majority of polar routes connect the US Eastern seaboard to Asia. If polar routes involve 

a larger proportion of business-related travel relative to all flights on average, using the average value of lost time may 

understate the economic impact. Moreover, it is unclear what percentage of people on these flights are U.S. citizens. 

We therefore simply assume ~90%, to be consistent with our previous assumption about the percentage of polar flights 

operated by U.S. carriers. Multiplying these estimates together, we arrived at a cost to passengers of $0.9-5 million 

(=~10,000-30,000 passengers x ~124-209 minutes delayed x ~$0.785 per minute x 0.9 U.S. citizens). 

6.3.2.b. More Extreme Event Scenario

Under more extreme conditions, we estimate space weather impacts that could cost U.S. airline passengers ~$6-

200 million. This estimate is also based on the value of lost passenger time of ~$47.10 per hour (~$0.785 per minute), 

as outlined in our moderate event scenario. Recall that our extreme scenario assumes that ~200-6,000 domestic flights 

are cancelled in the US. This may in turn potentially impact ~80-90 passengers per flight (see Table 30 and footnotes 

for details). Note that the average lost time per cancellation (e.g. rebooking process, etc.) has been estimated at ~457 

minutes per passenger [FAA, 2016]. This suggest total costs to passengers of our extreme event that may be ~$6-200 

million (=200-6,000 cancelled flights x ~80-90 passengers per flight x 457 minutes per passenger x $0.785 per minute). 

6.4 Aviation References 

American Meteorological Society, 2007. Integrating Space Weather Observations & Forecasts into Aviation 

Operations. American Meteorological Society & Solar Metrics Policy Workshop Report

Baker, D.N. and L.J. Lanzerotti. 2016. Resource Letter SW1: Space Weather. American Journal of Physics. Vol. 

84, No. 3.

Bütikofer, R., E.O. Flückiger, L. Desorgher, and M.R. Moser. 2008. “The extreme solar cosmic ray particle event on 

20 January 2005 and its influence on the radiation dose rate at aircraft altitude.” Science of the Total 

Environment. Volume 391, Issues 2-3. Pages 177-183.

Campbell, A., S. Buchner, E. Petersen, J. B. Blake, J. Mazur, and C. S. Dyer (2002), SEU measurements and 

predictions on MPTB for a large energetic solar particle event, IEEE Trans. Nucl. Sci., 49, 6, 1340-1344.

Cannon, P.; Angling, M., Barclay, L., Curry, C., Dyer, C., Edwards, R., et al., 2013. Extreme space weather: impacts 

on engineered systems and infrastructure, UK Royal Academy of Engineering, London, ISBN 1-903496-95-0.

Department of Transportation, 2016. The Value of Travel Time Savings:

Departmental Guidance for Conducting Economic Evaluations.

Dyer, C. S., F. Lei, S. N. Clucas, D. F. Smart, and M. A. Shea (2003), Solar particle enhancements of single event 

effect rates at aircraft altitudes IEEE Trans. Nucl. Sci., 50, 6, 2038-2045, doi: 10.1109/TNS.2003.821375.
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Dyer, C.S., Truscott, P., Sanderson, C., et al. 2000. Cosmic radiation effects on avionics, an increasing hazard in the 

new millennium, in: Presented at 22nd International Congress on Aeronautical Sciences, Harrogate, UK, 

September 2000.

Federal Aviation Administration (FAA), 2016. Update to the Business Case for the Next Generation Air 

Transportation System (NextGEN) based on the Future of the NAS Report. Available at: 

https://www.faa.gov/nextgen/media/BusinessCaseForNextGen-2016.pdf

Getley, I. L., M. L. Duldig, D. F. Smart, and M. A. Shea (2005), Radiation dose along North American 

transcontinental flight paths during quiescent and disturbed geomagnetic conditions, Space Weather, 3, 1, 

S01004, doi: 10.1029/2004sw000110.

Getley, I. L., L. G. I. Bennett, B. J. Lewis, B. Bennett, C. S. Dyer, A. D. P. Hands, and M. L. Duldig (2010), 

Evaluation of new cosmic radiation monitors designed for aircrew exposure assessment, Space Weather, 8, 1, 

S01001, doi: 10.1029/2009sw000492.

Jones, J.B.L., R.D. Bentley, R. Hunter, R.H.A. Iles, G.C. Taylor, and D.J. Thomas. 2005. “Space weather and 

commercial airlines.” Advances in Space Research. Volume 36, Issue 12. Pages 2258-2267.

Lantos, P., and N. Fuller (2003), History of the solar particle event radiation doses on-board aeroplanes using a semiempirical model and Concorde measurements Radiation Protection Dosimetry, 104, 3, 199-210.

NavCanada, 2016. The Next Level. 2016 Annual Report. 

National Oceanic and Atmospheric Agency (NOAA). 2004. Service Assessment: Intense Space Weather Storms 

October 19-November 7, 2003.

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7. Key Findings and Conclusions 

This study advances our overall understanding of the potential impacts of space weather and in addition to 

stimulating timely discussions, provides a solid, tractable foundation for future work. The systematic approach 

developed for exploring and synthesizing the many qualitative and quantitative complexities of this topic can also be 

readily applied to other sectors known to be impacted by space weather (e.g. trains, pipelines). Further, this study is 

based on scientific and engineering literature addressing space weather events, and expert stakeholder understanding of 

the physical effects and key concerns. Below we summarize several initial key findings from this study:

1. Space weather impacts are a real concern

The concept of “space weather” has advanced over the past decade from something mostly known to space 

researchers to a topic of concern to policy specialists, public officials, and many in the general public. Specifically, three 

key policy efforts were recently issued regarding space weather: the October 2016 Executive Order entitled 

“Coordinating Efforts to Prepare the Nation for Space Weather Events,” the “Space Weather Action Plan” issued by the 

Office of Science and Technology Policy in October 2015, and the “Space Weather Research and Forecasting Act” 

introduced as Senate Bill 2817 in April 2016. There is also traction internationally, with a handful of other 

socioeconomic impact studies underway, as well as a United Nations and US workshop on the International Space 
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Weather Initiative held August 2017. Industry stakeholders contacted for this study demonstrated evidence that space 

weather has the potential to cause significant impacts and support the development of improved understanding of the 

hazards, risks, and costs. 

2. Stakeholders are interested and committed to helping 

Contrary to popular belief, industry stakeholders have been very forthcoming with information; this may be in 

part related to the fact that they have a vested interest in the quality of the research that is being done. Stakeholders were 

very responsive to our inquiries. They emphasized the importance and challenges involved and generously provided 

their time, insights, and feedback to help guide and strengthen our endeavor. Stakeholders were also able to readily 

discuss and connect the physical effects identified for their sector to our five different impact categories. Many 

emphasized, however, that almost all of the impacts we identified also apply to other non-space weather hazards. 

Overall, stakeholders helped shape our ultimate approach and inform our assumptions, and were thrilled that this effort 

aimed to capture their understanding and perspective on the issue.

3. Impacts are complex and not well understood

The social and economic impacts of space weather intersect the fields of physics, engineering, industry 

operations, and economics. A limited number of previous studies have assessed the social and economic impacts of 

space weather. Some of the complexities include modern society’s lack of a direct experience of a severe space weather 

event, the rapidly evolving technological advances, and impacts that are not directly proportional with storm magnitude. 

Though our study initiated as an economic-centric approach, it was quickly evident that the problem first requires 

analytical mapping of space weather events and the physical effects by sector to the downstream social and economic 

impacts. Additionally, stakeholders engaged in this study emphasized that it is intractable at this point in time to 

rigorously connect the magnitude of a space weather event to our list of physical effects and ultimately to the types and 

sizes of the impacts that may result. To this end, we developed an analytical framework that accounts for much of the 

complexity and can accommodate additional information as it is acquired. Our study produced cost estimates using 

expert opinion and existing data and identified additional research needed to further refines these estimates including the 

estimation technique. 

4. Demonstrated value of defensive investments and SWPC science 

The estimated costs of proactive measures that prevent impacts are low compared to the impacts that could be 

realized during space weather events. Our cost estimates suggest that preventative expenditures associated with 

Defensive Investments and Mitigating Actions tend to be small relative to the much larger potential costs that result from 

the other impact categories including Asset Damage, Service Interruptions, and Health Effects. These proactive costs 

are an indication that such investments might payoff, though we did not explore the reduction in economic impacts 

enabled by Defensive Investments or Mitigating Actions. Scientific research on space weather contributes knowledge 

that is essential for designing and engineering robust and safeguarded systems Stakeholders discussed the central 

importance of space weather products and services as trigger points for Mitigating Actions such as the forecasts and 
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alerts provided by NOAA’s SWPC (Figure 1). Many stakeholders also noted that a severe event may cause 

disproportionate impacts in regions that do not experience more moderate space weather events since they lack the 

familiarity, training, and preparedness that accompanies more frequent exposure to potentially hazardous conditions. 

5. Applicability of study to the value of NOAA’s investments and to inform program planning 

This study has implications to help inform the value of science and forecasting investments and to improve the 

focus of investments relevant to societal outcomes (e.g. areas subject to significant impacts). A necessary first step in 

assessing the value of improving NOAA’s forecasting capabilities is the ability to estimate the economic impacts. These 

economic impacts cannot be estimated without understanding the impact of space weather across key technological 

sectors. Only after these impacts are understood, a value chain linking research and forecast investments to societal 

outcomes can then be produced and used to make decisions about where to invest. Specifically, NOAA can prioritize 

investments in new products and services that demonstrate a clear linkage to improving societal outcomes. This effort 

is the critical first step towards developing an approach for transparently establishing priorities that maximize societal 

value. 

Additionally, the analytical framework developed in this study identifies some initial information on who uses 

NOAA’s products, services, data and science; how they use it; and how they benefit from it. While specific NOAA staff 

might have access to this information, a concerted effort should be made to identify the information that is being 

collected, how it can be used in programmatic evaluation and planning, and how to make it accessible. One possible 

approach discussed amongst the study team and relevant for this study is to release the final report with a request and 

mechanism that will allow anyone to respond to the findings. This might entail, for example, the establishment of a 

dedicated email account or Google Form inviting feedback and comments. This would allow a wider variety of 

individuals to constructively contribute their knowledge and thoughts to this effort. This repository of input could help 

establish future collaborates and also provide a wealth of ideas for future work to pursue. 
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8. Recommended Next Steps

The goals of this initial NOAA effort were to capture, synthesize, and share what is currently known about the 

social and economic impacts of space weather. In order to advance our collective understanding of this important but 

not well studied topic [Eastwood et al., 2007], we encourage others to challenge, expand, and refine what is presented 

herein. We furthermore recommend the following next steps that we think are essential for this is to become a more 

tractable research problem that others can productively contribute their knowledge and expertise to. Next steps are listed 

in order of priority, with short-term steps requiring relatively less effort that escalate into longer-term steps requiring 

more substantial effort. 

Critical Review 

This interdisciplinary study spans a large number of scientific, engineering, and economic topics. We tried our 

best to carefully include essential technical details and key concepts from each of these fields into our analysis. Although

our effort was guided by extensive input and iterative feedback from stakeholders and experts, it is important for this 

report to be further critically reviewed by knowledgeable individuals not yet engaged. To this end, the study team will 

be submitting this work to a journal for publication at the conclusion of this project. In addition to the critiques and 

revisions that will accompany the peer-review process, contributing our analysis to the literature is essential for 

stimulating much needed research interest and attention on this topic. 

Discuss Findings 

 

This initial effort attempts to fill a large knowledge gap that is essential to other ongoing efforts and timely 

discussions within the U.S. and abroad. The contents of this report should be considered preliminary and this document 

viewed as a tool for stimulating critical discussions that need to occur within and across different technological sectors, 

institutions, and disciplines. To this end, we recommend that NOAA and/or other entities use this document as a 

mechanism for soliciting input, fostering dialogue, and building the working relationships necessary for advancing our 

understanding of this important but challenging real-world issue. This could occur, for example, via round table 

discussions, the establishment of a dedicated email account, and/or an online community forum. It is essential to create 

a variety of easy opportunities for a wider variety of individuals to contribute their knowledge and this would also help 

foster future collaborations. 

Establish Best Practices 

The growing recognition of space weather’s ability to cause social and economic impacts has led to a handful 

of recent and concurrent studies on the topic by other countries and research institutions [e.g. National Research Council,

2008; Biffis and Burnett, 2017; Oughton, 2017; Luntama et al., 2017]. Our study team has had limited but insightful 

interactions with representatives of these other efforts. At the 2017 Space Weather Workshop, for example, we came 

together for a day-long exchange to better understand similarities and differences in terms of project scopes, challenges, 

and methodologies. We collectively agreed that at the conclusions of our independent efforts, it would be fruitful to 

more thoroughly debrief and discuss our experiences as well as compare and contrast our different studies including 

approaches and findings. This could, for example, lead to a clear articulation of the various challenges inherent to this 
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type of an analysis and the establishment of best practices for studying space weather impacts. This can help guide those 

wishing to conduct similar studies, allowing them to learn and build from these early efforts. This is also important since 

some of these efforts are not yet, and may not become, publically available. 

Conduct Case Studies 

This study establishes an initial, transparent methodology for deriving quantitative estimates of various 

categories of impacts across our four different sectors of interest. Our effort was in part restricted by our inability to find 

well documented, detailed accounts of impacts observed during historic space weather events. A more extensive 

consideration, application, and verification of our estimation techniques to the impacts that we have collectively observed 

as a society, in the form of case studies, should be central to future efforts. At this point in time, for example, it is unclear 

whether or not the information necessary for this recommended next step exists and/or is publically available. Clearly 

establishing what needs to be known in the advent of an event will enable the rapid collection, rigorous assessment, and 

quantitative reporting of impacts associated with any future events. This has been essential for strategically managing 

and responding to other natural hazards (e.g. hurricanes, tornados, earthquakes, tsunamis, etc.). This is especially timely 

since we are entering a new solar cycle, with an anticipated upswing in solar activity. 

Analyze Sensitivity

This study identifies key variables and parameters that need to be known in order to estimate impacts. In many 

instances, we were unable to find the appropriate data for constraining these inputs and therefore relied upon expert best 

judgement or used order of magnitude assumptions based on available but coarse information sources. A more robust 

exploration of estimate sensitivity and parameter space would help diagnose where more detailed information is 

necessary for reducing the uncertainties in our cost estimates. For example, it would be helpful to at the very least 

understand which inputs change our cost estimates by factors versus by orders of magnitudes. 

Add Context 

This study explored the full spectrum of potential impacts and then, considered in more depth those that seemed 

to be the most significant as identified by stakeholder discussions. Before refining these estimates or proposing 

additional estimates for impacts not quantitatively covered in our report, we recommend adding context to the numbers 

presented herein. This could include an assessment of how potential costs compare to other costs within the industry 

including those imposed by other natural hazards and also how these costs may be increasing or decreasing with time to 

better understand what issues may be growing or diminishing within these industries. Such context is essential for truly 

understanding the importance of these impacts and can help establish clear priorities for future research. 

Update Estimates 

Research on this topic requires a sustained attention and iterative effort for it to advance and keep pace with our 

growing technical understanding of space weather and our modern society’s rapidly evolving dependence on potentially 

vulnerable technologies. Impacts not only depend on technologies but also on various business and governmental 

changes. The opening of Russian airspace for polar flights, for example, introduced new airline vulnerabilities to 
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moderate space weather events. Policies instated across the power sector, including those by Federal Energy Regulatory 

Commission (FERC) and National Energy Regulatory Commission (NERC), may soon reduce the probability of impacts 

to electricity across all sized space weather events. A better understanding of impacts will occur through many different 

U.S. Space Weather Action Plan (SWAP) efforts including the finalization of benchmarks for an extreme event 

[Executive Office of the President, 2017] and the vulnerability assessments of our nation’s Critical Infrastructure 

[Executive Office of the President, 2015a,b]. Keeping pace with change and incorporating the results of concurrent 

efforts is essential if this work is to stay current and relevant to decision making and policies. 

Explore Interdependencies 

This study independently considers impacts to the U.S. of space weather events resulting from four different 

technological sectors. We did not consider impacts that may result, for example, due to the known effects of space 

weather on other important sectors (e.g. trains, pipelines, etc.). We also did not consider potentially more catastrophic 

scenarios due to the known coupling between different sectors and also different space weather phenomena. Nor did we 

explore any of the international dimensions of this problem, including impacts that may result abroad as a result of U.S. 

impacts or else impacts that may result in the U.S. due to the impacts of space weather on other countries. These 

additional considerations and complexities should be carefully examined and considered as we begin to better understand 

impacts across different sectors and across different countries. 

8.1 References

Biffis, E. and C. Burnett. 2017. Report on the UKSA-funded IPSP SWx/SWe socio-economic study. Report on the 

ESA Space-Weather Socio-Economic Study L5 in Tandem with L1: Future Space-Weather Missions 

Workshop. March 6-9, 2017

Eastwood, J.P., E. Biffis, M.A. Hapgood, L. Green, M.M. Bisi, R.D. Bently, R. Wicks, L.A. McKinnel, M. Gibbs, and 

C. Burnett. 2017. The Economic Impact of Space Weather: Where Do We Stand? Rick Analysis, Vol. 37, 

No. 2

Executive Office of the President, 2015a, National Space Weather Strategy. 

Executive Office of the President, 2015b, National Space Weather Action Plan. Product of the National Science and 

Technology Council. 

Executive Office of the President, 2017. Space Weather Phase I Benchmarks. Product of the Space Weather 

Operations, Research, and Mitigation Committee of The National Science and Technology Council. 

Luntama, J.P, N. Bobrinsky, and S. Kfraft. 2017. Report on the ESA Space-Weather Socio-Economic Study L5 in 

Tandem with L1: Future Space-Weather Missions Workshop. March 6-9, 2017

National Research Council. 2008 Severe Space Weather Events – Understanding Societal and Economic Impacts: A 

Workshop Report. National Academies Press. 

Oughton, E. 2017. Report on the Cambridge SWx/SWe Socio-Economic Study, Report on the ESA Space-Weather 

Socio-Economic Study L5 in Tandem with L1: Future Space-Weather Missions Workshop. March 6-9, 2017