Service Assessment 

Intense Space Weather Storms 

October 19 – November 07, 2003 

 

U.S. DEPARTMENT OF COMMERCE 

National Oceanic and Atmospheric Administration 

National Weather Service 

Silver Spring, Maryland
Cover Photographs: 

Left: From a vantage point approximately 1/100 of the distance from Earth to the Sun, 

the Advanced Composition Explorer (ACE) satellite provides critical advance warning of 

geomagnetic storms that can overload power grids, disrupt spacecraft operations, and 

interrupt communications on Earth. The ACE satellite was one of many spacecraft that 

experienced significant problems during the late October 2003 solar activity. 

Right: A dramatic depiction of the November 04 flare, probably the brightest X-ray solar 

flare ever seen by the GOES XRS X-ray sensor (estimated at X28), seen here in an SXI 

image. 
Service Assessment 

Intense Space Weather Storms 

October 19 – November 07, 2003 

April 2004 

U.S. DEPARTMENT OF COMMERCE 

Donald L. Evans, Secretary 

National Oceanic and Atmospheric Administration 

Vice Admiral Conrad C. Lautenbacher, Jr., Administrator 

Oceanic and Atmospheric Research 

Richard D. Rosen, Assistant Administrator 

National Weather Service 

David L. Johnson, Assistant Administrator 
Preface 

The October-November 2003 solar storms rank as one of the largest outbreaks of 

solar activity in recent history. The global effects were wide-ranging, impacting power 

grids, airline flights, spacecraft operations, and much more. Media interest and public 

awareness of this activity was at the highest levels ever. 

Due to the magnitude of this space weather event, a service assessment team was 

formed to examine the space environment warning and forecast services provided by the 

NOAA Space Environment Center. Service assessments provide a valuable contribution 

to our ongoing efforts to improve the quality and timelessness of our products and 

services for the protection of life and property. Findings and recommendations from the 

assessment team are offered to improve techniques, products, services, and the 

information provided to the American public and citizens around the world. 

 Richard D. Rosen, Ph.D. David L. Johnson 

Assistant Administrator Brigadier General, USAF (Ret.) 

Oceanic and Atmospheric Research Assistant Administrator 

National Weather Service 

 

April 2004 

ii
Table of Contents 

 Page

Preface ......................................................................................... ii 

Service Assessment Team .................................................................. iv 

Acronyms ..................................................................................... vi 

Service Assessment Report ..................................................................1 

 Introduction and Overview......................................................... 1 

 Warning and Forecast Services ................................................... 5 

 Customer Support and Impacts.................................................... 10 

Facts ........................................................................................... 31 

Findings and Recommendations ........................................................... 33 

Best Practices ................................................................................. 37 

Appendix A – NOAA Space Weather Scales ............................................ 39 

Appendix B – X-ray Flare Classification ................................................. 43 

 

Appendix C – Event Statistics ............................................................. 45 

 

Appendix D – Historical Perspective ...................................................... 47 

 

iii
Service Assessment Team 

The service assessment team was activated on December 01, 2003. Team

members interviewed many on SEC’s diverse customer list. Customers included multiple 

government agencies and private sector parties, with both U.S. and international interests. 

Their concerns were wide-ranging, from biological impacts of radiation storms to space 

weather effects on technology infrastructure, in space and on Earth. The team was 

comprised of the following individuals: 

Christopher Balch Team Leader, Lead Space Weather Forecaster, NOAA 

Space Environment Center (SEC), Boulder, Colorado 

Bill Murtagh Lead Author, Space Weather Forecaster, NOAA Space 

Environment Center, Boulder, Colorado 

 

LT David Zezula NOAA Corps, Space Weather Forecaster, NOAA Space 

Environment Center, Boulder, Colorado 

Larry Combs Space Weather Forecaster and SEC Media Spokesperson, 

NOAA Space Environment Center, Boulder, Colorado 

Gayle Nelson Lead Space Weather Operations Specialist, NOAA Space 

Environment Center, Boulder, Colorado 

Ken Tegnell Space Weather Operations Specialist, NOAA Space 

Environment Center, Boulder, Colorado 

 

Misty Crown Space Weather Operations Specialist, NOAA Space 

Environment Center, Boulder, Colorado 

Barbara McGehan NOAA Public Affairs Officer, Boulder, Colorado 

Other valuable contributors include: 

Joe Kunches Chief, Space Weather Operations, NOAA Space 

Environment Center, Boulder, Colorado 

Capt. Kelly Doser Officer-In-Charge (OIC), Operating Location P, Air Force 

Weather Agency, Boulder, Colorado 

 

Terry Onsager Physicist, NOAA Space Environment Center, 

Boulder, Colorado

iv
The following provided significant inputs to the storm impact lists: 

Mike Golightly Manager, NASA Space Radiation Analysis Group, NASA 

Johnson Space Center, Houston, Texas 

John Kappenman Manager, Applied Power Solutions Division, Metatech 

Corporation, Duluth, Minnesota 

David Webb Air Force Research Lab (AFRL), Solar and Solar Wind 

Disturbance Prediction group (VSBXS), Hanscom AFB, 

Massachusetts 

Joe Allen Scientific Secretary - Scientific Committee On SolarTerrestrial Physics (SCOSTEP), NOAA-NGDC, Boulder, 

Colorado 

Capt. Herbert Keyser Chief, Space Weather Branch, A.F. Weather Agency, HQ 

AFWA/XOGX, Omaha, Nebraska 

v
Acronyms 

ACE Advanced Composition Explorer - NASA research satellite monitoring the 

 space environment beyond Earth's magnetic field 

ADEOS Advanced Earth Observing Satellite 

Afr A daily index of geomagnetic activity at Fredericksburg, VA, derived as 

 the average of the eight 3-hourly a indices 

AFWA Air Force Weather Agency

Ap A 3 hourly equivalent amplitude of magnetic activity derived from the Kp 

 index 

ATC Air Traffic Controllers 

CDS Coronal Diagnostic Spectrometer on SOHO 

CHIPS Cosmic Hot Interstellar Plasma Spectrometer satellite

CME Coronal Mass Ejection 

DGPS Differential Global Positioning System 

DHS Department of Homeland Security 

DMSP Defense Meteorological Satellite Program

DP Dynamic Positioning 

EDP Electron Density Profile 

EIT Extreme ultraviolet Imaging Telescope - used to view the sun in extreme 

 ultraviolet wavelengths 

EPAM Electron, Proton, and Alpha Monitor – its data disclose approaching 

 shocks 

ESA European Space Agency 

EUV Extreme UltraViolet 

FAA Federal Aviation Administration 

GALEX Galaxy Evolution Explorer 

GIC Geomagnetically Induced Current 

GOES Geostationary Orbiting Environmental Satellite 

GPS Global Positioning System

GSFC NASA Goddard Space Flight Center

Ha Hydrogen Alpha - 6353 Angstrom filtered imagery used to detect features 

on the Sun 

HALOE Halogen Occultation Experiment (on UARS) 

HF High Frequency (3-30 MHz) 

ICESat Ice, Cloud, and Land Elevation Satellite 

IMF Interplanetary Magnetic field 

ISS International Space Station 

JAXA Japan Aerospace Exploration Agency 

vi
JSC Johnson Spaceflight Center 

km/s Kilometers per Second

Kp A 3 hourly planetary index of geomagnetic activity 

L1 Lagrangian point. A point on the Sun – Earth line about 1/100 of the 

 distance from Earth to the Sun

LASCO Large Angle Spectrometric Coronagraph - used for detecting coronal 

mass ejections 

LEMS Low Energy Magnetic Spectrometers 

mph Miles Per Hour 

NASA National Aeronautics and Space Administration

NERC North American Electric Reliability Council 

NESDIS National Environmental Satellite, Data, and Information Service

NOAA National Oceanic and Atmospheric Administration 

NRC Nuclear Regulatory Commission 

nT nanoTesla – Unit of magnetic field measurement 

OAR Office of Oceanic and Atmospheric Research 

Pfu Particle Flux Units (1 pfu = particle/cm^2-s-ster) 

RHESSI Reuven Ramaty High Energy Solar Spectroscopic Imager 

RSTN Radio Solar Telescope Network 

RXTE Rossi X-ray Timing Explorer (satellite) 

SEC Space Environment Center 

SEM Space Environment Monitor - instrument package aboard GOES 

spacecraft 

sfu Solar Flux Units (1 sfu = 10^-22 W/m^2/Hz) 

SI Sudden Impulse - sudden perturbation in Earth’s magnetic field due to 

 compression from a shock in the solar wind 

SIRTF Space Infrared Telescope Facility 

SOHO SOlar and Heliospheric Observatory - a joint NASA/ESA research 

 satellite 

SOON Solar Observing Optical Network 

SSIES Special Sensor - Ions, Electrons, and Scintillation (instrument on DMSP) 

SSN Smoothed Sunspot Number - an average of 13 monthly RI numbers, 

centered on the month of concern 

SWEPAM Solar Wind Electron, Proton, and Alpha Monitor - used to monitor solar 

 wind 

SXI Solar X-ray Imager on GOES - used to detect flare location 

TEC Total Electron Content 

TOMS Total Ozone Mapping Spectrometer (satellite) 

TRMM Tropical Rainfall Measuring Mission (satellite) 

UARS Upper Atmosphere Research Satellite 

UTC Universal Time Coordinated 

VHF Very High Frequency (30 – 300 MHz)

XRS X-ray Sensor on GOES 

vii
viii
Service Assessment Report 

Introduction 

Solar Cycle 23 began its 11-year cycle in May 1996 with a monthly smoothed 

sunspot number (SSN) of 8.0, and peaked in April 2000 at 120.8. October 2003 marked 

the 92nd month in Cycle 23 and the early-October sunspot count reflected another quiet 

month in the unremarkable waning phase of an average solar cycle. The quiet period 

would abruptly end. With little warning, large and intense sunspot groups developed on 

the solar surface, and by the end of October 2003, NOAA Space Weather Forecasters 

were engaged in the most active and demanding solar activity epoch in years. In the 60 

days prior to this outbreak, two solar energetic event alerts were issued. In contrast, 

during the late October – early November three week period, NOAA SEC staff issued 

over 250 solar energetic event watches, warnings, and alerts, as three of the largest 

sunspot clusters in over 10 years emerged on the surface of the Sun. 

Impacts were wide ranging. The Sydkraft utility group in Sweden reported that 

strong geomagnetically induced currents (GIC) over Northern Europe caused transformer 

problems and even a system failure and subsequent blackout. Radiation storm levels were 

high enough to prompt NASA officials to issue a flight directive to the ISS astronauts to 

take precautionary shelter. Airlines took unprecedented actions in their high latitude 

routes to avoid the high radiation levels and communication blackout areas. Rerouted 

flights cost airlines $10,000 to $100,000 per flight. Numerous anomalies were reported 

by deep space missions and by satellites at all orbits. GFSC Space Science Mission 

Operations Team indicated that approximately 59% of the Earth and Space science 

missions were impacted. The storms are suspected to have caused the loss of the $640 

million ADEOS-2 spacecraft. On board the ADEOS-2 was the $150 million NASA 

SeaWinds instrument. Due to the variety and intensity of this solar activity outbreak, 

most industries vulnerable to space weather experienced some degree of impact to their 

operations. 

Widespread concerns by affected commercial sectors generated intense global 

media interest. The storms were covered by major media organizations around the world. 

SEC staff participated in over 300 news broadcasts and interviews, assisting media 

outlets from Chile to Hong Kong. The high levels of activity fueled more public and 

media interest than any other solar event or period this cycle. Customer concerns and 

heightened public awareness produced a frenzy of interest in the SEC web page, which 

saw the daily average hit-rate of 500,000 rise to over 19 million hits on October 29. Solar 

images and solar activity stories were flashed on newspapers around the world, making 

“solar flares” a household term. 

This activity outbreak occurred 42 months after Cycle 23’s peak in April 2000. 

While late cycle active periods have occurred in the past, it is unusual to see this extreme 

level of activity during this stage of the solar cycle. Seventeen major flares erupted on the 

sun between October 19 – November 05, 2003, including perhaps the most intense flare 

1
ever seen by a GOES XRS instrument – a huge X28 flare (NOAA scale R5 – see 

Appendix A and B) on November 04. Many of these flares had associated radiation 

storms, including an S4 (severe) storm on October 29. Geomagnetic storm periods were 

observed on 12 of the 20 days, with two storms reaching the G5 (extreme) level on 

October 29 and 30. The last occurrence of such late cycle activity was April/May 1984 

during Cycle 21. That period saw a total of nine major flares, 52 months after the 

December 1979 peak of the Cycle. It should also be noted that 28 major flares occurred 

in 1973 during the late stages of Cycle 20. Cycle 20 peaked in November 1968. 

Overview 

Solar activity from October 19 to November 05, 2003 originated from three 

sunspot regions, numbered by SEC forecasters as Regions 484, 486, and 488. While each 

of these regions was remarkable in size and magnetic complexity, Region 486 was by far 

the most significant. With a size exceeding 2600 millionths of the solar disk (over 13 

times the size of Earth), Region 486 was the largest sunspot group observed since 

November of 1990. It maintained its extreme size, complex magnetic structure, and thus, 

great flare potential, during its entire transit across the visible disk (Figure 1). Twelve of 

the seventeen major flares that occurred during this period came from Region 486. Of 

the twelve major flares, three stand out as defining events: the X17 (R4) on October 28, 

X10 (R4) on October 29, and X28e (R5) on November 04. 

 23 

 Figure 1. White light and magnetic imagery showing the solar 

Oct

26

Oct

28

Oct

24

Oct

25 

Oct

27

Oct

30 

Oct

S16E70 S16E57 S15E45 S15E31 S16E18 S17E04 S16W11

31

Oct

29

Oct

01

Nov

S18W23 S17W36 S17W49

Region 486

02

Nov

S17W62

White Light

Image Magnetic Field

Image

 disk transit of super Region 486. Courtesy of Big Bear Solar Observatory. 

Solar flares are measured by their X-ray emissions as recorded by the GOES XRS 

instrument (Appendix B). On October 28 at 1110 UTC, a powerful X17 flare occurred 

from Region 486 (Figure 2), producing a category R4 (severe) radio blackout on the 

NOAA Space Weather Scales (Appendix A). This flare had intense radio bursts including 

a 245 MHz burst near 500,000 sfu – one of the largest ever recorded. The flare occurred 

near center disk and was promptly followed by a very fast coronal mass ejection (CME) 

2
and a strong radiation storm. The solar radiation storm quickly reached category S3 

(strong) levels and, after 13 hours, exceeded S4 (severe) levels. This was the second most 

intense radiation storm this cycle, and the fourth most intense since measurements began 

in 1976. The CME was observed by the LASCO coronagraph on board the SOHO 

spacecraft and had an estimated speed of 2125 km/s (over 5 million mph). The CME Sunto-Earth transit took just 19 hours, arriving at Earth on October 29 at 0613 UTC (the 

fastest on record is 17 hours in August 1972). The fast CME impacted Earth’s magnetic 

field and produced a G5 (extreme) geomagnetic storm. The storming lasted for twentyseven hours and was the sixth most intense geomagnetic storm on record (since 1932). 

 

N

E W

S

 Figure 2. EIT 195 (left) and LASCO imagery (right) of R4 flare and full 

 halo CME on October 28. Note the bright emission that surrounds the Sun 

 (the halo), indicating that the CME is directed toward Earth. (NASA/ESA)

Less than 24 hours after the X17 flare, Region 486 produced another major 

eruption. On October 29 at 2049 UTC, an X10 flare (S4 - severe radio blackout) erupted, 

followed by an S3 (strong) radiation storm and another powerful, Earth-directed CME 

(Figure 3). The estimated speed for this extremely fast CME was 1948 km/s and the 

transit time was, again, 19 hours, arriving at Earth at 1600 UTC on October 30. Another 

G5 (extreme) geomagnetic storm followed quickly on the heels of the powerful October 

29 storm (Figure 4) and lasted for twenty-four hours. 

 Figure 3. GOES SXI (left) and LASCO imagery (right) of S4 flare and 

 halo CME on October 29. (NOAA/NASA) 

3
 

 

 

 Figure 4. The Kp index for the back-to-back G5(extreme) 

K >4 

K =4 

K <4 

 geomagnetic storms. (NOAA/NCEP/SEC) 

The last event of significance during this outbreak was an X28e (estimated) major 

flare from Region 486, producing category R5 (extreme) radio blackout levels on 

November 04 at 1950 UTC (Figure 5). The GOES XRS instrument became saturated at 

the X17.5 level for 12 minutes during this flare. Using historical flare data and 

mathematical modeling, an estimated peak flux of X28 was assigned. This flare was one 

of the strongest flares since GOES XRS measurements began in 1976. Despite the record 

size of the flare, its location near the west limb of the Sun limited its impact. The 

associated CME, as seen in Figure 5, was directed away from Earth. As a result, the 

subsequent radiation storm and geomagnetic storm only reached category S2 (moderate) 

and G1 (minor) levels. 

 Figure 5 – GOES SXI (left) and LASCO imagery (center) of November 04, X28e flare 

 And CME. On the right GOES XRS measurement of the record event. 

 (NOAA/NCEP/SEC, NASA) 

A total of 17 major flares (>R2), six radiation storms (>S1), and four severe 

geomagnetic storms (>G2) occurred in this 20-day period. 

4
Warning and Forecast Services 

NOAA's Space Environment Center is the national and world warning center for 

disturbances in the space environment. The Space Environment Center provides real-time 

monitoring and forecasting of solar and geophysical events, and issues space weather 

watches, warnings and alerts to multiple government and private entities in the United 

States. 

Geophysical Activity Forecast 

The first of the three big sunspot groups (Region 484) emerged rapidly near the 

southeast limb of the Sun on October 18. The daily forecast on the 18th showed increased 

percentage probabilities for flare activity. This region continued in a growth phase 

through October 19 and by midday produced an X1 flare (R3 radio blackout). The flare’s 

impulsive signature and location near the southeast limb suggested to forecasters that no 

radiation or geomagnetic storm was likely. No warnings were issued and no storms

occurred. 

By October 21, Region 484 maintained considerable size and complexity, but it 

was the activity originating from behind the southeast limb that alarmed forecasters. At 

least four large coronal mass ejections were observed to occur from a source behind the 

east limb between October 18 - 22. The combined potential of this new region (numbered 

by SEC as Region 486 on October 22) and the existing Region 484 prompted SEC to 

issue a Space Weather Advisory. This, in turn, led to a NOAA Press Release. The 

advisory alerted customers that a prolonged period of solar activity was expected: 

SEC Space Weather Advisory 

Official Space Weather Advisory issued by NOAA Space Environment Center, Boulder, 

Colorado, USA 

SPACE WEATHER ADVISORY BULLETIN #03- 2 

2003 October 21 at 06:11 p.m. MDT (2003 October 22 0011 UTC) 

**** INTENSE ACTIVE REGIONS EMERGE ON SUN   

Two very dynamic centers of activity have emerged on the sun. NOAA Region 484 developed 

rapidly over the past three days and is now one of the largest sunspot clusters to emerge during 

Solar Cycle 23, approximately 10 times larger than Earth. This region, which is nearing the center 

of the solar disk, already produced a major flare (category R3 Radio Blackout on the NOAA 

Space Weather Scales) on 19 October at 1650 UTC. The region continues to grow, and 

additional substantial flare activity is likely. 

A second intense active region is rotating around the southeast limb of the sun. Though the 

sunspot group is not yet visible, two powerful eruptions occurred on 21 October as seen from the 

LASCO instrument on the SOHO spacecraft. These eruptions may herald the arrival of a volatile 

active center with the potential to impact various Earth systems. 

Further major eruptions are possible from these active regions as they rotate across the face of 

the sun over the next two weeks. Agencies impacted by solar flare radio blackouts, geomagnetic 

storms, and solar radiation storms may experience disruptions over this two-week period. These 

include satellite and other spacecraft operations, power systems, HF communications, and 

navigation systems. 

5
Early on October 22, an Earth-directed coronal mass ejection (CME) was 

observed to originate from Region 484, which was nearing disk center. SEC forecasters 

viewed the ejection as a moderate event and expected the CME to arrive at Earth a few 

days later. It was expected to create some periods of strong storming, but a G4 (severe) or 

G5 (extreme) geomagnetic storm was not expected. Geomagnetic storm watches were 

issued for October 24 – “ The CME from today is expected to arrive mid-day on the 24th 

of October and may produce periods of strong storming...Afr prediction for 24 Oct: 

040.” The timing of a NASA press release concerning an historical solar event that 

occurred in 1859 unfortunately coincided with the NOAA press release on the current 

activity. Confusion among certain national media sources led to some suggestions that 

the predicted CME impact would be one of the strongest ever. SEC staff spent a 

considerable amount of time quelling the concerns of the public and correcting 

misconceptions in the media. The over-hyped event even took its toll on Wall Street 

where several companies with space assets saw their stock suffer a sell off as investors 

feared impact from the CME. The CME impacted Earth’s magnetic field on October 24 

at 1530 UTC. The sudden impulse (SI) was followed by approximately two hours of G3 

(strong) geomagnetic activity, and the maximum Afr was 41. 

 Sun-Spot Worries Flare at Sirius 

 By Scott Moritz 

 Senior Writer 

 10/24/2003 03:20 PM EDT 

 Sirius (SIRI:Nasdaq - commentary - research) investors were sweating it out Friday. 

 The stock sold off in unusually heavy trading as investors worried that solar flares 

 could damage the company's satellites. 

 The Street.com – Oct 24, 2003 

 ------------------------------------------------------------------------------ 

 

 

 

 “...the storm created big headaches for the Space Environment Center in Boulder. 

 Forecasters there spent much of Friday trying to correct misconceptions about the 

 storm’s severity.” 

 Rocky Mountain News – Oct 25, 2003 

Nine significant flares occurred between October 22 - 27, most of them from

Region 486 and all of them in the R2 (moderate) - R3 (strong) range. As Region 486 

approached center disk, new Region 488 emerged rapidly, also at center disk. Three 

major sunspot groups now populated the visible solar disk. By October 27, solar storm 

forecast probabilities were at the highest levels of the solar cycle. 

Arguably, the largest solar event of Solar Cycle 23 erupted on October 28 at 1110 

UTC. Over 500 customers immediately received the severe flare alert. The huge X17 

flare from disk center prompted forecasters to immediately issue radiation storm

6
warnings. The radiation storm began just 20 minutes after the flare onset and lasted for 

days. LASCO coronagraph imagery showed a powerful and fast, Earth-directed CME. 

The extreme magnitude and speed of the event led the forecasters to examine the 

historical record to provide some guidance for the likely Sun-Earth transit time. It was 

found that the fastest Sun-Earth transit of a CME observed to date for the current solar 

cycle was 28 hours, from the X5 flare on July 14, 2000. Forecasters expected this CME 

transit to be even faster, and predicted a transit time of 24 hours. Geomagnetic storm

watches were issued predicting the strongest geomagnetic storm of Solar Cycle 23. 

SPACE WEATHER ADVISORY BULLETIN #03- 3 

2003 October 28 at 10:55 a.m. MST (2003 October 28 1755 UTC) 

** ** SOLAR ACTIVE REGION PRODUCES INTENSE SOLAR FLARE ****

The dynamic solar regions reported on October 21 continue to produce high levels of solar 

activity. NOAA Region 486 produced a category R4 (severe) radio blackout with an associated

category S3 (strong) solar radiation storm on October 28 at 1110 UTC (6:10 A.M. EST). The 

SOHO/LASCO instruments also observed a full halo coronal mass ejection with this activity, 

which is Earth directed. This region is the second largest in size this solar cycle. 

As a result of this activity a category G4 (severe) geomagnetic storm is expected with periods of 

category G5 (extreme) levels possible. The solar radiation storm is also expected to continue at 

strong (G3) levels for the next 48 hours. Further major eruptions are possible from these active 

regions as they rotate across the face of the Sun over the next few days. 

SEC had additional staff on duty in anticipation of the CME arrival. By 0400 

UTC on October 29, low-energy particle sensors on the ACE satellite hinted that the 

CME was fast approaching. Power grid customers were notified of the imminent threat. 

At 0601 UTC on the 29th, a remarkably fast CME impacted the ACE spacecraft. 

Important sensors on ACE were already rendered useless due to the severe radiation 

storm; however, the transit time alone pointed to a powerful geomagnetic storm.

Forecasters immediately issued severe geomagnetic storm warnings, and with just 13 

minutes elapsed since the impact at ACE, the CME slammed Earth’s magnetic field at 

almost 5 million mph. An extreme (G5) geomagnetic storm ensued and persisted for over 

24 hours. 

Forecasters continued to ascribe very high flare probabilities on October 29, and 

theses were validated at 2010 UTC when another powerful flare erupted from Region 

486. The X10 (R4 – severe radio blackout) flare generated another fast Earth-directed 

CME. Radiation storm warnings already in effect for the previous day’s storm were now 

extended an additional 24 hours. Geomagnetic storm watches were issued for another 

extreme (G5) geomagnetic storm, which was expected to arrive within 24 hours. The 

CME impacted the ACE spacecraft at 1440 UTC on October 30. Severe geomagnetic 

storm warnings were issued, and within one hour, the geomagnetic field was once again 

undergoing severe geomagnetic storming. 

The X8 flare that erupted on November 02 (Figure 6) from Region 486 (nearing 

the west limb of the sun) highlighted the importance of a space-based coronagraph for 

CME measurements. LASCO imagery was unavailable on November 02 and Type II 

radio sweeps (a proxy for CME speed) were proven unreliable as a CME speed indicator 

7
in the previous week’s CMEs. Forecasters could assume with confidence that a large 

CME occurred, but knew that its direction and speed were highly uncertain. Historical 

data revealed that the geomagnetic response from large CMEs that originated from near 

the west limb varied dramatically. Given the intensity of the recent storms, forecasters 

predicted another severe storm with an onset in less than 25 hours. Updated LASCO 

imagery on November 03 (Figure 6), revealed that while there was an Earth-directed 

component (full halo CME was identified), most of the ejecta were directed away from 

Earth: an impact was likely, but the storming would be considerably less than initially

expected. Also significant was the deceleration of the CME as it moved away from the 

Sun. The initial prediction for a <25 hour arrival was changed to ~40 hours. A short-lived 

geomagnetic storm began early on November 04 (36.5 hour transit) and briefly reached 

severe levels before quickly subsiding. 

 

 Date: Mon, 3 Nov 2003 19:06 

 Subject: Full Halo CME on 2003/11/02, frontsided 

 LASCO and EIT observed a full halo CME on 2003/11/02. The event was first 

 Observed in C2 at 17:30... The mean plane-of-sky speed for this event was 

1826 km/s at PA 272, with evidence for strong deceleration. 

Excerpt from the LASCO halo CME message received November 03. (NASA) 

Figure 6. EIT image showing location of X8 flare on November 02 (left), with associated 

large CME off SW limb (center), and relatively weak geomagnetic response on 

November 04 (right). (NASA, NOAA/NCEP/SEC) 

The November 03 forecast issued by SEC indicated that major flare probabilities 

would remain at record highs for at least two more days. The X-class flare probability for 

November 04 - 05 was 75%. 

8
 Event Probabilities 04 Nov-06 Nov 

 Class M 90/90/70 

 Class X 75/75/50 

 Proton 99/75/50 

 

Excerpt from the Joint USAF/NOAA Report of Solar and Geophysical Activity 

On November 04, Region 486 produced what is estimated to be an X28 flare, one 

of the largest solar flares on record. Statistical databases indicate that radiation storm and 

geomagnetic storm potential was high from large flares on the west limb, but storm

intensities would likely be weak - “Day two's geomagnetic activity may stay enhanced 

due to a glancing blow from the X28 flare from today.” Forecasters accurately predicted 

the subsequent radiation storm and geomagnetic storm as category S2 (moderate) and G1 

(minor) levels. 

NOTE: The GOES-12 Solar X-ray Imager (SXI) experienced a high voltage anomaly on 

Sepember 02, 2003. SXI imagery was not available in the Space Forecast Center from

September 02 to October 28, 2003. SEC Operations submitted a formal request to NOAA 

and NESDIS management to resume SXI operations, and real-time SXI imagery was 

made available in the forecast center on October 28, 2003. 

9
Customer Support and Impacts 

SEC’s customer base is wide ranging and includes multiple organizations (private 

and public) involved in deep space missions, satellite and space operations in near-Earth 

orbits, the airline industry, electric utilities, communications and navigation interests, and 

more. Support provided by SEC during the high solar activity period differed 

considerably from agency to agency. The following paragraphs address the impact of 

space weather on the various technologies both on Earth and in space. While addressing 

impacts, it is important to categorize the effectiveness of SEC services in aiding 

customers to prepare and react to a rapidly changing and hostile space environment. In 

all, 278 alerts, watches and warnings were issued totaling 93,680 customer contacts in the 

20-day period. Of this total, 253 alerts, watches, and warnings were issued following 

energetic events from the three large sunspot groups. In contrast, the average monthly 

number of alerts, watches, and warnings for energetic events during the 12-month period, 

October 2002 – September 2003, was 25. The October – November 2003 tally does not 

include the critical services provided on the SEC webpage, nor does it take into account 

the hundreds of phone inquiries from industry interests around the globe. 

NASA SRAG/ISS 

Close coordination between SEC and the NASA Space Radiation Analysis Group 

(SRAG) at Johnson Spaceflight Center (JSC) is vital. SRAG is responsible for ensuring

that the radiation exposure received by astronauts remains below established safety 

limits. Telephone briefings between both agencies are conducted daily, and the support 

tempo increases significantly during special operations such as space shuttle missions and 

extra-vehicular activity (space walks). SEC also provides close support to the ISS 

Environments System Team (Boeing/NASA). During periods of high solar activity, SEC 

maintains constant communication with NASA. The coordination between the agencies 

during this solar activity outbreak was at a level unseen since 1991. 

During this 20-day period, SEC conveyed via telephone to NASA, over 140 

alerts, watches and warnings. Detailed discussion on the analysis and prediction of solar 

events occurred daily. The extensive coordination between SEC and NASA resulted in 

actions by SRAG that ensured astronauts would not exceed acceptable risk from exposure 

to radiation. Management at NASA/JSC released the following: 

“Solar flare activity caused flight controllers to issue 

contingency directives for the ISS Expedition 8 crew to briefly 

relocate to the aft portion of the station's Zvezda Service Module 

and the Temporary Sleep Station (TeSS) in the U.S. Lab. The 

Expedition 8 crew of Commander Mike Foale and Flight 

Engineer Alexander Kaleri spent brief periods of time 

 in the aft end of the Zvezda Service Module, which is the most 

shielded location aboard the International Space Station from 

higher levels of radiation. During Tuesday (Oct. 28) there The ISS 

Courtesy of NASA/SRAG

10
 were five, 20-minute periods during which the crew was asked to remain in the aft end of 

Zvezda.” 

These actions cut the potential radiation exposure of the crew by approximately 

50%. Only twice before has NASA asked the ISS crew to seek shelter during solar 

radiation storms - November 2000 and November 2001. 

NASA also decided to do a ground-commanded powerdown of the billion dollar 

robotic arm and workstation, which are sensitive to radiation events. They also prepared 

to take other precautionary actions (e.g., shut down the S-band antenna controller and 

external color TV cameras) if radiation levels were to increase more than they did. The 

ISS Environments System Team also reported that the ISS experienced abnormal 

frictional drag.

Deep-Space Missions 

Numerous deep-space missions in progress during the October-November time 

frame were impacted by the severe solar activity. All these missions rely on NOAA data 

for anomaly assessment, and most, if not all, subscribe to SEC’s alert list. Scientists 

stressed the importance of situational awareness during solar storms – “If we had not 

known about the flare we could have floundered for days and perhaps even sent 

commands that would have been detrimental.” – Stardust Team. The most significant 

impact during the October-November activity was the likely loss of the Martian 

Radiation Environment Experiment (MARIE) on the NASA 

Mars Odyssey mission. The list of impacts below highlights 

some details of known anomalies at this time. It is expected 

that further details will emerge in the months ahead, but the 

true assessment of the October-November 2003 solar activity 

impacts may never be fully understood or revealed. 

Mars Odyssey 

Photo courtesy of 

NASA/ JPL

Mars Odyssey - Spacecraft entered safe mode during the 

severe radiation storm. During downloading on October 29, 

the spacecraft had a memory error that was corrected with a 

cold reboot on October 31. The MARIE instrument on the 

Mars Odyssey had a temperature red alarm leading it to be 

powered off on October 28. The MARIE instrument is not 

expected to recover. Ironically, MARIE’s mission was to 

assess the radiation environment at Mars to determine 

the radiation risk that astronauts on a Mars mission may 

encounter. 

11
NASA Newsroom Press Release 

 

2001 Mars Odyssey 

November 26, 2003

Mars Odyssey Mission Status

 The martian radiation environment experiment on NASA’s 2001 Mars Odyssey orbiter has collected data 

continuously from the start of the Odyssey mapping mission in March 2002 until late last month. The 

instrument has successfully monitored space radiation to evaluate the risks to future Mars-bound 

 astronauts. Its measurements are the first of their kind to be obtained during an interplanetary cruise

and in orbit around another planet. On Oct. 28, 2003, during a period of intense solar activity, the 

 instrument stopped working properly. Controllers’ efforts to restore the instrument to normal operations 

have not been successful. These efforts will continue for the next several weeks or months. 

Stardust - Comet mission went into safe mode due to read errors; recovered. 

SMART-1 - Had auto shutdown of engine due to radiation levels in lunar transfer orbit. 

Reported a total of 3 shutdowns; decided not to thrust below altitude of 10,000 km. 

Mars Explorer Rover - Spacecraft entered “Sun Idle” mode due to excessive star tracker 

events. Waited out event and recovered. 

Microwave Anisotropy Probe - Spacecraft star tracker reset, and backup tracker 

autonomously turned on. Prime tracker recovered. 

Mars Express - Spacecraft had to use gyroscopes for stabilization, because the flare made 

it impossible to navigate using stars as reference points. The radiation storm blinded the 

orbiter's star trackers for 15 hours. The flares also delayed a scheduled Beagle 2 checkout 

procedure. 

Earth Orbiting Spacecraft 

The GFSC Space Science Mission Operations Team indicates that approximately 

80% of the Earth and Space science missions (both deep space and near-Earth missions) 

experienced effects from the October-November activity. And though space weather is a 

major consideration during spacecraft design, about 40% of the missions either turned off 

their instruments or took other protective action in response to the severe solar activity. 

All organizations involved with space operations rely on NOAA data for 

situational awareness and anomaly assessment, but during the October-November 

activity, the importance of NOAA data and SEC services for pursuing mitigating actions 

were also very apparent. The anomalies identified in this document are just some of the 

impacts reported. Many anomalies will never be reported and many others are still in the 

investigation stage. 

12
ADEOS-2 - Japan Aerospace Exploration Agency 

(JAXA) lost contact with the ADEOS-2 satellite, 

following an intense CME, which impacted Earth’s 

magnetic field on October 24. ADEOS-2 is an 

environmental observation LEO satellite, launched in 

December 2002 by the Japanese Space Agency. It was 

designed to collect data on global warming and other 

climate-change phenomena. Developed at a cost of 70 

billion yen ($640 million), it had an expected lifespan 

of three years. On board the ADEOS-2 platform was 

the NASA SeaWinds instrument, designed to map 

wind speed and direction across much of the Earth's ice-free 

ADEOS-2 (Midori-II) JAXA

oceans each day. The SeaWinds had a total cost of $154 million ($138 million for 

development; $16 million for five years of operations); additional NASA ground network 

costs of $11 million, which was to support the overall ADEOS-2 mission. NOAA was 

contributing $14 million for the NASA ground network support to the overall Adeos-2 

mission. Loss of the Sea Winds instrument caused a major system acquisition and 

development loss to the U.S. Navy. ADEOS-2 is not expected to recover. Though space 

weather is suspected as a major contributor to the ADEOS-2 demise, no official cause has 

been identified at the time of this writing. 

Japan Aerospace Exploration Agency Press Release 

Earth Observation Operation of Midori-II 

(Advanced Earth Observing Satellite-II, ADEOS-II) 

 The Japan Aerospace Exploration Agency has been investigating the 

 possibility of recovering the observations of Midori-II after an anomaly was 

 detected in the satellite on October 25 (Saturday), 2003. JAXA has been

 continually trying to send the satellite commands to restore its functions, and analyze its current

status. 

 However, as a result of our investigation, analysis, and inability to re-establish 

 any communications with the satellite, JAXA found today that the possibility of restoring the

operations of Midori-II is extremely slim. 

 JAXA would like to express our sincere apologies to all Japanese citizens, 

 Midori-II users, and parties concerned, including the Ministry of Environment,

 NASA (the National Aeronautics and Space Administration) and CNES (Center 

 National d'Etudes Spatiales), whose observation equipment is onboard Midori-II. 

 SEC staff assisted JAXA in their recovery efforts and anomaly assessment. A note 

from Tateo Goka of JAXA to SEC expressed appreciation – “Thank you again for your 

great help on ADEOS-2 anomaly study.” 

 

Advanced Composition Explorer (ACE) - EPAM Low Energy Magnetic Spectrometer 

(LEMS 30) damaged: Noise levels increased in several ion channels and remain 

abnormally elevated. This instrument is not expected to recover. 

13
Note: While ACE is not Earth orbiting, it is not as far away as deep space missions so is 

included here. 

 

Kodama, Data Relay Test Satellite (DRTS) - Went into safe mode on the morning of 

October 29 during the severe (S4) solar radiation storm. The DRTS is a geostationary 

communications satellite that relays data among Low Earth Orbit (300-1,000 km altitude) 

spacecraft (including the International Space Station) and ground stations. JAXA’s 

associate executive director indicated, “The excessive signal noise coming from the Earth 

sensor assembly suggests the satellite was affected by a proton barrage. The most likely 

culprit is the solar flare.” From a Tokyo press release: 

TOKYO -- The massive solar flare that erupted Oct. 28 has shut down and possibly crippled an

experimental communications satellite owned by the Japanese Aerospace Exploration Agency 

(JAXA), officials said. The Data Relay Test Satellite (DRTS), also known as Kodama, went into 

safe mode, essentially shutting down all noncritical functions, the morning of Oct. 29, according 

to Tsuguhiko Katagi, JAXA’s associate executive director. 

. 

Status: Kodama was recovered on November 07, 21:19 JST

CHIPS - Satellite computer went offline on October 29, and contact was lost with the 

spacecraft for 18 hours (loss of 3-axis control because its single board computer stopped 

executing). When contacted, the spacecraft was tumbling, but was recovered 

successfully. It was offline for a total of 27 hrs. 

DMSP F16 - SSIES sensor lost data twice, on October 28 and November 03; Microwave 

sounder lost oscillator; Switched to redundant system. 

CHANDRA - Observations halted on several occasions during the October-November 

activity, including an extended outage from October 28 – November 01. 

GOES-9, 10 and 12 - High bit error rates (9 and 10) and magnetic torquers disabled (12) 

due to solar activity. 

Inmarsat (fleet of 9 geosynchronous satellites) - Controllers at their Satellite Control 

Center had to quickly react to the solar activity to control Inmarsat’s fleet of 

geosynchronous satellites. Two experienced speed increases in momentum wheels 

requiring firing of thrusters, and one had an outage when its CPU tripped out.

Other satellites with known anomalies during this timeframe include: FedSat, 

POLAR, GALEX, Cluster, RXTE, RHESSI, Integral, Genesis, and more. On October 

28, 2003 the NOAA-17 spacecraft experienced a significant problem with the scan 

motors of the AMSU-A1. The instrument was powered down and no recovery efforts are 

planned. The cause of this failure is unclear at this time. SEC staff assisted NASA, 

JAXA, ESA, and commercial satellite companies with spacecraft anomaly assessments. 

 

14
TV and Pay Radio Satellite Services: TV satellite controllers told of many problems 

with maintaining routine operations. They had to resort to "manual attitude control" for 

18-hour to 24-hour periods due to magnetopause crossing events that affected the attitude 

controller of two or more of their fleet. A component "burned out" in one circuit box 

(ungrounded) in a newer satellite that has required a workaround (they were successful). 

Pay radio satellite had several short-lived periods where they lost satellite lock. 

Department of Defense: Satellite operations over high-interest regions were lost for 29 

hours when three spacecraft either experienced anomalies or were shut down to avoid 

damage due to space weather.

Mitigating Actions Taken by Spacecraft Operations Teams

Aqua, Landsat, Terra, TOMS, TRMM - NASA’s Earth Sciences Mission Office 

directed all instruments on these five spacecraft be turned off or safed due to the extreme 

solar storm prediction (October 29). 

 Aqua - From the Atmospheric Infrared Sounder (AIRS), Table of Data 

Outage Periods:

 29 Oct – 06 Nov: AIRS turned off as a precaution because of three large 

 solar flares and associated coronal mass ejections. 

SIRTF - In orbit drifting behind Earth, turned off science experiments and went to Earth 

pointing due to high proton fluxes (October 28). Four days of operations lost. 

CDS instrument on SOHO spacecraft at the L1 point commanded into Safe mode for

three days (October 28-30). 

UARS/HALOE - Turn on of the instrument was delayed due to solar activity. 

Department of Defense – Air Force Space Command corrected for satellite orbit 

changes by running satellite drag models based on advanced warning of geomagnetic and 

solar activity indices.

 

SEC sources indicate that additional satellites were put into safe modes, solar 

panels rotated, and operations reduced. It is important to note that actions not taken due 

to accurate assessment and prediction of the space environment are also very important. 

For example, SEC staff worked closely with a satellite company that provides highresolution satellite imagery to a huge customer base that includes multiple DoD agencies. 

Company management was prepared to “safe” the satellite in late October to avoid space 

weather damage. They estimated the cost of such action at “several million dollars per 

day.” SEC staff accurately predicted space weather storm levels would remain below 

their “safing” threshold. Based on the SEC forecast, the company maintained continuous 

operations through the storm. They followed up with this note of verification and support: 

15
 “During the recent large solar activity, our company did not experience any 

anomalies. Thanks to the availability of NOAA SEC space weather data, we decided with 

confidence not to take any spacecraft safing actions. Safing procedures will power off all 

components except those required to maintain spacecraft health and safety, and will 

maneuver the spacecraft to a "defensive" posture.

 

 Continued availability of the NOAA SEC data is vital to our safe operations in the 

presence of elevated solar activity.” 

Airlines 

Airlines have long recognized the potential cost benefits of flying polar routes for 

the North America to Asia flights. The end of the cold war opened these flight paths, and 

by the end of the last decade, several airlines were operating on these new efficient routes 

(Figure 7). Airlines using polar routes benefit from additional passenger revenue, while 

producing significant savings on fuel and crew costs. Typical time and cost savings for a 

polar flight from New York to Singapore is 209 minutes and $44,000. A polar route from

Boston to Hong Kong will save 138 minutes and $33,000 as compared with previous 

non-polar routing. 

Polar flights departing from North America use VHF (30-300 MHz) 

communication with the Canadian ATCs. Flights will communicate initially with the 

Edmonton control center and then transition to Arctic Radio - the responsible agency for 

relaying messages between the flight crew and controllers at the various control centers. 

While the flight’s initial communication with Arctic Radio is generally on VHF, they 

soon switch to HF (3 – 30 MHz). Satellite communication (SATCOM) is considered a 

backup during polar flights, but it is rarely available above 82 degrees north latitude

(Figure 8). 

 Figure 7. North America routes to Asia. 

16
Flying time for airline pilots is restricted to 16 hours per day. A typical flight 

duration for a polar route from a North American destination to Asia is over 15 hours. If 

the flight must divert for any reason, an additional stop-off is required. This results in

considerable time loss, additional fuel, and the added time will require a whole new crew. 

The average cost of this kind of diversion is approximately $100,000. 

 Figure 8. Typical communication modes for polar routes. 

 Although there may be many reasons for an airline to want to fly over the poles, 

it is these regions that are impacted most by solar activity. Airlines on polar routes must 

contend with degraded communications; potential biological impacts from radiation 

storms; impacts to navigational systems (generally a lesser concern); and as avionics 

evolve, a potential impact to electronic systems. The October-November solar storms

created a significant disruption to airline operations, and though difficult to accurately 

assess, the dollar cost was likely in the millions. 

Airlines and ground controllers experienced communications problems almost 

daily during the October – November solar activity outbreak. Initially (October 19 – 23), 

the degraded HF communications were due to elevated X-ray solar emissions and the 

moderate to strong solar flare activity. On October 19, following the X1 (R3) flare, Air 

Traffic Centers reported moderate-to-severe impacts on all HF groups and HF service 

was degraded for over two hours. In response, a major carrier rerouted three polar flights 

from Polar Route 3 to Polar Route 4 (Figure 7), which is more desirable for data-link and 

Satcom. This required an additional 26,600 pounds of fuel and resulted in over 16,500 

pounds of cargo being denied. More impacts to airline operations were reported on 

October 24 following the onset of a G3 (strong) geomagnetic storm. Solar radiation 

remained at background levels, but high latitude communications were severely degraded 

due to the geomagnetic storm. These communication problems forced the Edmonton 

Center to release the following notice to airmen (NOTAM): 

17
 CZEG EDMONTON CENTRE (ACC)

 A8577/03 - ROUTE AND LEVEL RESTRICTIONS DUE TO GEO-MAGNETIC STORM

 IMPACT ON COMM IN EDMONTON ACC ALL FLT TRANSITING CZEG FIR N OF 5700N 

 AT FL290 OR ABOVE: 1. NORTHBOUND POLAR FLT PROCEEDING OVER DEVID, ORVIT

 OR RAMEL SHALL ROUTE VIA: A) 7500N 8000W - 8000N 8300W - PIGSO - 8852N

14100W - DEVID B) YRB - TAPSA - OVDON - 7810N 14100W - ORVIT C) 7000N 

 10500W - TAVRI - 8415N 14100W - RAMEL 2. ALL ACFT SHALL OPR ON PUB 

 TRACKS 3. NO LATERALS, NO DIRECTS WHILE E OF 7000W 4. ACFT THAT ARE 

 UNABLE TO OPR ON PUB TRACKS DUE TO THE NATURE OF FLT SHALL REQUIRE 

 PRIOR APPROVAL OF THE ROUTE FROM SHIFT MANAGER AT 1-(780)890-8397 5. 

 ZAN SHALL RESTRICT ALL EASTBOUND ACFT ENTERING CZEG FIR AT AND N OF 

 6900N TO 20 MIN IN TRAIL. 6. OPR ARE ADVISED THAT VHF AND HF COMM

 RELAYED FROM THE TRANS SITE TO ATC VIA SATELLITE MAY FAIL DUE TO THE 

 EFFECTS OF THE CURRENT INTENSE MAGNETIC STORM. CZEG WILL UPDATE THESE 

 MEASURES AS THE STORM IMPACTS BECOMES BETTER KNOWN. FOR INFO CONTACT: 

 CZEG SHIFT MANAGER 1-(780)890-8397/1-(877)342-2276 NATIONAL OPS CENTRE

 

These were the first of several such periods of severely degraded communication. 

As each major flare occurred, HF communications at low and mid-latitudes underwent a 

range of problems from minor signal degradation to complete HF blackout. Higher 

latitudes would experience even more difficulty following the onset of the radiation 

storms on October 26. Air traffic operators reported minor to severe impacts on HF 

communications every day between October 26 and November 05. Communications 

were so poor on October 30 that additional staff was necessary to handle air traffic. The 

radiation storms would also introduce a second major concern for the airlines - radiation 

effects on passengers and crew. 

SEC staff participated in teleconferences with major airlines at an average rate of 

three to five times a day. Teleconferences were conducted by SEC staff with airline 

dispatchers, pilots, and airline safety personnel as an important part of their decision 

making process. With SEC’s help, airlines made critical decisions about route and/or 

altitude restrictions to flight operations during solar activity. Flight Centers restricted 

flight paths due to degraded communications, but it was each individual airline’s 

responsibility to assess the radiation threat and take appropriate action. All commercial 

aviation interests were made aware of the radiation storm levels on October 28-29, when 

the Federal Aviation Administration (FAA) issued their first ever advisory suggesting 

that flights traveling north and south of 35 degrees latitude were subject to excessive

radiation doses (Figure 9). This FAA product is based on data from the NOAA GOES 

particle sensors and is an advisory only. Airlines are not required to take action based on 

this advisory. Currently, two major U.S. airline companies conduct flight operations over 

the poles, and both took action to limit radiation exposure to passengers and crew. Polar 

flights were rerouted during this period (e.g., between October 24 – 31, one major airline 

rerouted six polar flights to non-polar routes requiring fuel stops in Japan and/or 

Anchorage). Flights on the U.S. to Europe routes did fly at lower altitudes during this 

severe radiation storm. The FAA issued a Solar Radiation Alert for the following 

timeframes: 

18
 Start End Duration 

10/28 1208 UT 10/29 0603 UT 17h 55min 

10/29 2123 UT 10/30 1158 UT 14h 35min 

11/02 1808 UT 11/02 2343 UT 05h 35min 

Airlines have established their “go/no-go” radiation storm threshold at the S3 

level. Dispatchers informed SEC that they must make route decisions several hours in 

advance of the scheduled takeoff time and that a prediction of a storm being above or 

below the S3 level is vital. Maximum radiation storm intensity predictions are not part of 

SEC’s radiation storm warning procedures. Forecasters adjusted to this need and 

provided dispatchers with radiation storm maximum intensity predictions. Perhaps the

best example of the value of an intensity prediction was on November 04, when the X28 

(R5 extreme) flare erupted. Airline companies immediately assumed a flare this large 

would surely produce a significant radiation storm. Forecasters advised dispatchers that 

because of the source location on the sun, an S3 storm was not likely. No route alterations 

were made, and the prediction materialized when a moderate size S2 radiation storm

unfolded. SEC’s radiation storm warnings are currently under review. The support 

provided to the airlines by SEC was recognized in the following correspondence: 

 

Continental Airlines wants you to know how appreciative we are for the fantastic 

support we have received from the whole team at the NOAA Space Environment Center. 

The insight provided by your experts was extremely beneficial to the Continental Airlines 

operations team. We consider the information obtained from your web site and the 

conference calls with your experts to be an important component of our decision making 

process when it comes to applying route and/or altitude restrictions to our flight

operations due to solar activity. Continental Airlines effectively used your information

and input to define appropriate operational parameters for our flight operation thereby 

improving our safety and efficiency. 

 Your willingness to share your expertise and expectations concerning the 

solar event should be a model for other agencies when it comes to working together with 

industry. 

 Sincerely, 

 Sr Mgr SOCC 

Department of Defense 

A maritime interdiction mission, requiring 100% communications, was cancelled based 

on scintillation forecasts issued by AFWA Space Weather Operations Center. 

19
 

 Space Weather Message Code: ALTPAV Issue Time: 2003 Oct 28 2123 UTC 

 ALERT: Solar Radiation Alert at Flight Altitudes 

 Conditions Began: 2003 Oct 28 2113 UTC 

 Comment: 

 Satellite measurements indicate unusually high levels of ionizing radiation, coming 

 from the sun. This may lead to excessive radiation doses to air travelers at Corrected 

 Geomagnetic (CGM) Latitudes above 35 degrees north, or south. 

 Avoiding excessive radiation exposure during pregnancy is particularly important. 

 Reducing flight altitude may significantly reduce flight doses. Available data indicates 

 that lowering flight altitude from 40,000 feet to 36,000 feet should result in about a 30 

 percent reduction in dose rate. A lowering of latitude may also reduce flight doses but 

 the degree is uncertain. Any changes in flight plan should be preceded by appropriate 

 clearance. 

Figure 9 – Map and text of the FAA Solar Radiation Alert issued on October 28, 2003. A 

Solar Radiation Alert indicates a radiation storm is in progress that may lead to a 

substantial increase in radiation at aircraft altitudes in shaded areas shown on the map. 

(FAA) 

GPS Users 

GPS operations are affected by the changes in total electron content (TEC) of the 

ionosphere along the path to the satellite during large solar flares and geomagnetic 

storms. These kinds of solar activity can cause large increases and decreases in TEC, 

20
which impacts the accuracy of single-frequency GPS. Dual-frequency GPS receivers can 

better adjust to a disturbed ionosphere, but still experience some difficulty. 

GPS is used by millions of people around the world. Many GPS users will 

experience little or no impact during geomagnetic storms, but those requiring precise 

GPS measurements have a great need for SEC alerts and warnings. Those with the 

greatest concerns include FAA’s Wide-Area Augmentations Systems (WAAS), 

surveying companies using GPS measurements for land surveying, topographic work, 

and property boundary analysis; deep-sea drilling operations; land drilling and mining, 

and various DoD operations. 

The WAAS system was seriously impacted. For a 15-hour period on October 29 

and an 11-hour interval on October 30, the ionosphere was so disturbed that the vertical 

error limit, as defined by the FAA’s Lateral Navigation Vertical Navigation 

(LNAV/VNAV) specification to be no more that 50 meters, was exceeded. That 

translated into commercial aircraft being unable to use the WAAS for precision 

approaches.

Operators relying on GPS can and will take important actions during geomagnetic 

storms. During the October-November activity, companies delayed high resolution land 

surveying; postponed airborne and marine survey operations; cancelled drilling 

operations; and some, as was the case with the C.R. Luigs deep water drill ship, resorted 

to backup systems to ensure continuity of operations. An international oilfield services 

company issued an internal "technical alert" via their worldwide network, to alert their 

surveying and drilling staff on potential impacts from solar storms. They reported six 

cases of survey instrument interference in late October from sites around the world. By 

early November, the value of space weather services became very apparent to many 

agencies relying on the Global Positioning System. This is well reflected in this feedback 

from operators on the C.R. Luigs: 

The Solar warnings were very helpful. We encountered DGPS interruptions at 

the height of solar activity. These interruptions made the DGPS solutions un-reliable at 

the worst times. We ended up using primarily our acoustic array at the seabed as the 

primary solution for position when the DGPS solutions were affected. We now follow 

the Space Weather regularly. Thanks for your assistance. 

DP Operator 

C.R Luigs 

 The C.R Luigs is the largest state of the art 

 ultra-deep water drill ship in the world. It relies 

 on its Dynamic Positioning System (which 

 partially relies on GPS) for precise drilling in

 9.000 – 12,000 feet of water (drills wells 

 35,000 feet below sea level). When operating 

 efficiently, this Positioning System can hold the

 ship to within 3 meters of the required location.

21
Figure 10. TEC measurements from GPS following the X17 flare on October 28 (top) 

and during the extreme geomagnetic storm on October 30 (bottom). Typical TEC 

background values in the enhanced areas above are approximately 100-130 TEC units. 

The geomagnetic storm on October 30 produced TEC measurements that exceeded 250 

TEC units (extremely high) over portions of North America. (NASA/JPL) 

22
Antarctic Operations 

The Antarctic science groups and staff rely on MacRelay radio operations to 

provide essential radio communications between McMurdo Station and remote sites on 

the Antarctic. MacRelay is also responsible for communication links with aircraft and 

ships supporting the United States Antarctic Program. 

The primary source of communication is HF radio. 

MacRelay experienced over 130 hours of HF 

communication blackout during the October – 

November activity. 

Following an extended solar flare-induced 

HF outage earlier in this solar cycle, McMurdo staff 

developed a contingency plan to use Iridium

satellite phones as backup during HF outages. 

During these previous periods of severe solar 

activity (2000 – 2001), numerous support flights were 

MacRelay member checks SEC data 

(Photo courtesy Kris Kuenning – The 

Antarctic Sun) 

delayed for several days. During the October – November 2003 activity, the LC-130 

aircraft that service the remote sites used Iridium phones to communicate with McMurdo 

and the remote locations. And to ensure safety, take-off and landing restrictions changed 

during the HF blackout periods. The 150-meter cloud ceiling and 3.2 km of visibility was 

increased to 900 meters with 4.8 km of visibility. 

Scientific missions in the field (at camp) in Antarctica are required to 'check in'

with MacRelay communications under normal circumstances via HF. If they miss their 

'check in' then a rescue mission is considered. MacRelay was made aware that space 

weather was causing significant HF blackout conditions, allowing them to implement 

contingency plans. MacRelay received SEC alerts and warnings, but SEC staff also 

coordinated with MacRelay staff via telephone during the October-November activity. 

Electric Utilities 

The geomagnetic storms on October 29 and 30 were certainly among the strongest 

this cycle. When a CME impacts Earth’s magnetic field, the fluctuations generate electric 

fields on Earth, and the potentially damaging geomagnetically induced currents (GIC) 

can flow into power lines and transformers. The late October storms caused GICs that 

impacted power grids around the globe. 

Typically, when smaller, less powerful CMEs impact the geomagnetic field, GICs 

at a few amps to a few tens of amps can occur which can cause some problems for grid 

operators. Larger CMEs can generate GICs of well over 100 amps which can lead to 

transformer saturation and over-heating, false relay trippings, an increase of harmonics, 

voltage drops, and in worst case scenarios - a blackout of an entire grid and/or permanent 

damage to transformers. 

23
How impacting a CME is on the power grid depends on several factors. One of 

the most important variables is how the CME magnetic field will couple with Earth’s

magnetic field. Relatively weak CMEs will on occasion generate much stronger 

geomagnetic storms than larger CMEs that had greater potential, but coupled differently 

with the geomagnetic field. But even when strong storms occur, the potential impact on 

the grid depends on several factors. How much load is on the grid at the time of the storm

onset is critical. During those times of the day and year when electrical demands are low, 

the grid is not as vulnerable to impacts from GICs. The location on Earth where GICs are 

most intense is also important, because strong GICs in remote locations of the world 

won’t make much difference to the North American grid. Equipment type and preventive 

actions will also affect the degree of impact on the grid. 

The X17 and X10 flares that occurred on October 28 and 29, respectively, 

produced powerful geomagnetic storms. However, the magnetic storm coupling was 

considerably less than it could have been, and the resultant geomagnetically induced 

currents were not as large as many in the past. According to John Kappenman of the 

Metatech Corporation, both storms were "far less severe than a Superstorm status, and 

resulting GICs that did occur could perhaps be a factor of 3 to 10 times larger in most 

regions than those observed.” GICs in excess of 100 amps were observed, and 

Kappenman suggest that larger GIC’s were observed globally during the large shock on 

October 29, following the arrival of the first large CME from the X17 flare. 

Power companies in North America did experience some problems. Impacts and 

actions reported by grid operators included: less use and switching between systems; high 

levels of neutral current observed at stations throughout the country; a capacitor trip in 

the northwest (known to be GIC susceptible); transformer heating in the east – 

precautions were implemented; and a ‘growling’ transformer that was backed down to 

help cool it down. GIC impacts were more significant in Northern Europe where heating 

in a nuclear plant transformer was reported and a power system failure occurred on 

October 30 in Malmo, Sweden resulting in blackout conditions (Figure 12). 

Electrical companies took considerable effort to prepare for and be aware of the 

storm onsets. Companies received the standard suite of geomagnetic storm watches, 

warnings and alerts, but SEC staff also supplemented standard support with several 

phone discussions. Preventive action helped to counter the GIC stresses that were 

observed. A representative from the North American Electric Reliability Council (NERC) 

commented - “Although the bulk electric system was not significantly affected by the 

solar activity, some systems reported higher than normal GICs that resulted in 

fluctuations in the MW and MVAR output of some generating units, while the output of 

other units was reduced in response to the K-index forecast.” Responses to warnings 

included reducing system load, disconnecting system components, and postponing 

maintenance. Some actions taken by the U.S. Nuclear Regulatory Commission were 

included in their Power Reactor Status Report for October 30, 2003 (Figure 11). Many

utility companies expressed their appreciation for SEC’s efforts during the high solar 

activity – “Central Maine Power appreciates and values NOAA's SEC's efforts in keeping 

24
the public and electric utilities informed of pending space weather events (Nov 06, 

2003).” 

The military was forced to switch an Early Warning Radar from commercial to 

generator power to avoid damage from GICs. 

U.S. Nuclear Regulatory Commission 

Power Reactor Status Report for October 30, 2003 

 Unit Power Reason or Comment

Hope Creek 1 80 REDUCED POWER DUE TO SOLAR 

 MAGNETIC DISTURBANCES 

Salem 1 80 REDUCED POWER DUE TO SOLAR 

 MAGNETIC DISTURBANCES 

Braidwood 2 90 COASTDOWN TO REFUELING OUTAGE 

 REVIEWING SYSTEM PLANNING OPERATING 

 GUIDE FOR SOLAR FLARE RESPONSE 

Arkansas Nuclear 1 100 HOLDING OFF ON SWITCHYARD 

 MAINTENANCE FOR SOLAR FLARE 

Palo Verde 1 98 T-HOT LIMITED TAKING EXTRA READINGS 

 ON PLANT COMPUTE DUE TO SOLAR FLARE 

Comanche Peak 1 100 CANCELLED D/G SURVEILLANCE 

 DUE TO SOLAR FLARE RESPONSE 

Figure 11. Extracted from NRC Status Report on October 30, 2003 (NRC) 

25
October 31 - Sun storm causes problems for Swedish power system. The solar 

storm has caused technical glitches in Sweden's power system in the past few days 

and may be to blame for a blackout that affected 50,000 people on Thursday, October 

30. Magnetic solar storms can wreak havoc with electricity grids, and the effects continued to 

be felt on Friday, October 31, in the Nordic region, particularly in Sweden where problems 

with transformers at a nuclear station and in the grid were observed, officials said. Power 

was cut around 9 p.m. on Thursday in the southern Sweden city of Malmo and lasted 20 

minutes to a half hour, utility Sydkraft said in a statement. "We have not 100 percent 

identified the solar storm as the cause, but it might have been," said Sydkraft official Peter 

Sigenstam. A spokesperson for Sweden's national grid, Svenska Kraftnat said that two 

transformers had malfunctioned, but the problems were quickly fixed and had not caused 

power outages to consumers. 

Figure 12. Power grid problems in Sweden are discussed in this excerpt from the 

Department of Homeland Security Infrastructure Report, November 03, 2003. (DHS)

Aurora 

The Aurora Borealis and Aurora Australis (northern and southern lights) are the 

visible manifestation of geomagnetic disturbances. With the advent of the Internet and 

other advances in communication mediums, entrepreneurs are seizing commercial 

opportunities to provide aurora alerts, image galleries and photo sales, and even aurora 

viewing tours. The public’s interest in aurora viewing generated numerous contacts from

media and the general public alike. 

Though not a part of SEC’s product line, SEC staff assisted with dozens of 

inquiries about aurora viewing. The extreme and prolonged geomagnetic storms on 

October 29 and 30 ensured widespread middle and even low latitude aurora. Aurora 

sightings occurred from California to Houston to Florida. Tremendous aurora viewing 

was also reported from Australia, mid-Europe and even as far south as the Mediterranean 

countries. 

26
Aurora over North America – October 30, 

2003 (USAF DMSP satellite) 

Aurora over Colorado – October 29, 2003

(Photo by Ginger Mayfield)

Media Response 

The media response was undoubtedly the largest volume ever experienced at 

SEC. Over 300 media contacts occurred over this 20-day period. Details of the solar 

activity were sent over the AP network, CNN, NE Paging Service, NPR, Reuters News, 

Metro Network, and others. SEC staff provided daily updates and interviews to TV, 

Radio, and Internet sources (national and local – ABC, NBC, CBS, FOX, CNN, Weather 

Channel, PBS, and many more). Several live interviews were conducted for International 

media such as the Canadian Radio Corporation, BBC, and the Voice of America. SEC 

members participated in an hour-long worldwide interview on VOA, fielding questions 

from listeners on every continent. Newspapers and magazines around the world 

(Washington Post, NY Times, Chicago Tribune, USA Today, Herald Newspaper 

Glasgow, LePress Canada, London Times, PC Magazine, New Scientist, Discover, and 

more) would check daily to update their stories and do articles concerning the forecasts 

and possible problems and effects from this flurry of activity. The NY Times sent a 

reporter to SEC to shadow a forecaster for two days. The subsequent Times article 

included an extended front section article. Other agencies such as NASA and ESA also 

experienced a deluge of media interest in the activity outbreak. 

Internet Services

The SEC Web site and the Internet proved to be an invaluable information tool. 

This fact became most apparent when the web site could no longer handle the volume of 

interested users. Prior to the onset of the late October-November activity, SEC’s webpage 

averaged 0.5 million hits daily. Following the first SEC Space Weather Advisory Bulletin 

and NOAA Press Release in late October, web site access increased to around 3 million 

hits per day. This overwhelmed the system, and the site had to switch to an OAR Web 

Farm in order to handle the volume of file transfers. The site received 19 million hits on 

October 29 (Figure 13). In July 2003, during Hurricane Claudette, the NOAA National 

27
Hurricane Center website averaged 3.7 million hits per day. During the 15-day period – 

October 24 Oct through November 07, the SEC website averaged 6.2 million hits per 

day. 

 

Figure 13. SEC Web site statistics (NOAA/NCEP/SEC)

Partner Coordination 

Space Weather Operations Center, Air Force Weather Agency (AFWA):

SEC works closely with its Air Force sister center in Offutt AFB, Nebraska. Daily 

coordination calls are standard procedure and play an important role in developing 

accurate and consistent forecasts of space weather. During the October-November 

activity period, coordination between the centers was at unprecedented levels. 

Both centers relied on each other’s data to ensure accurate and timely products 

were provided to their respective customers. Both SEC and AFWA have internal models 

for forecasting energetic particle events and geomagnetic storming. SEC has additional 

models they make available on their website, which AFWA uses to help in their 

forecasting processes. Immediate and intense coordination occurred between the two 

centers to produce the best-possible forecast of the space weather parameters for both 

customer bases. This complementary utilization of resources provided enhanced warning 

to the nation's DOD and civilian concerns impacted by space weather. 

SEC relied on solar observations provided by the Air Force’s Solar Electro 

Optical Network (SEON). AFWA operates five observatories (Figure 14) that monitor 

solar activity in both optical and radio wavelengths. These observations of flare location, 

radio burst intensity, and radio sweep characteristics were all used in radiation storm and 

geomagnetic storm forecasts. The 24-hour (global network) solar observations were vital 

28
in assessing the complexity and potential of the three major active regions. This was 

especially important during the October activity, because the SXI imager was not 

operational during the first 11 major flares from October 19 – 28. Knowing the solar 

source of the large X-ray flares was imperative for radiation storm forecasting. Radio 

data from the sites were key inputs to SEC products and support for the FAA and the 

NWS Doppler radar sites. Solar activity discussion bulletins from the SEON sites 

provided forecasters with critical details on the developments in the three large active 

regions. The mix and integration of information between these two centers ensured 

consistent, accurate and timely alerts and predictions. The Chief of the Space Weather 

Operations Center at AFWA had this to say: “Daily forecast discussions were 

irreplaceable. These helped our forecasters focus, and provided a consolidated forecast 

for the nation. Also, the expertise from SEC in evaluating the significant events allowed 

us to focus on the resulting impacts to our customers.” 

The AFWA Space Weather Branch issued 458 unclassified warnings and 99 

National Intelligence Community (NIC) warnings for space weather during the October–

November outbreak. 

U.S. Air Force Solar/Electro-Optical Network 

(SEON)

San Vito IT

Palehua HI Sag Hill MA

Learmonth AU

SEON

Sites

R R

Holloman NM

R

R

R

R S

S

S

S

RSTN

SOON

AFWA

Offutt AFB, NE

 Figure 14. The SEON Network provided critical real-time optical 

 and radio patrol during the severe October-November solar storms. 

 (AFWA) 

NASA SOHO-LASCO Operations Team - Coronagraph observations are the 

only way to directly observe coronal mass ejections (CME). In addition, they are able to 

indicate halo CMEs, which, when Earth-directed, are the best and earliest predictor of

29
strong geomagnetic disturbances. The LASCO team issues coded and plain language 

alerts when Earth-directed halo CMEs are observed (Figure 15). The LASCO team’s 

detailed analysis and reporting of the many CMEs during the October-November period 

was very valuable in operations. Additionally, LASCO scientists were available for 

consultation, and SEC staff gleaned important details on the various events. 

 

 UCMEO 93001 301028 1500/ 

 31028 61054 91420 0001/ 360// 233// 42125 

 31028 61036 91212 20916 10486 1111/

 99999 

 PLAIN 

 LASCO and EIT observed a full halo CME on 2003/10/28. The event was first observed in C2 

 at 10:54 UT as a bright loop front over the W limb; by 11:30 UT the front had developed into a 

 full halo CME, very bright all around the occulting disk. The front first appeared as a full halo 

 CME in C3 images at 11:42 UT. The mean plane-of-sky speed for this event was 1785 km/s at 

 PA 92, with evidence for strong acceleration below 5Rs. The height-time profile above 5Rs I 

 is moderately linear and has a mean plane- of-skyspeed of 2125 km/s 

 The CME was probably associated with an X17.2 X-ray flare observed by EIT between 10:36 – 

 12:012 UT, centered at S16E09 with peak emission at 11:12 UT. GOES records this flare from 

 AR 0486 between 09:51 - 11:24 UT with peak emission at 1110 UT. A very large EIT wave, 

 and dimming,were observed in association with this event. This event has therefore been 

 determined frontsided. Please note that a large prominence can be seen erupting slightly 

 below the active region prior to the flare, and this prominence material can clearly be seen in 

 LASCO images, to the S.

Figure 15. LASCO CME message and images following the X17 flare on October 28, 2003

(NASA/ESA)

30
FACTS 

FACT: A total of 17 major X-ray flares (R2 – R5) were observed during the late 

October – early November time frame. These flares and the associated solar activity 

were some of the strongest on record. The November 04, 2003 flare saturated the GOES 

X-ray sensor for 12 minutes and is estimated at X28 (R5 extreme). This event is perhaps 

the largest flare ever measured by GOES X-ray sensors (measurements began in 1975). 

FACT: The solar activity produced some of the most intense geophysical events on 

record. Six distinct radiation storms were discerned, including the second largest storm

(S4 severe) of Solar Cycle 23. This storm ranked 4th in the all-time list dating back to 

1976. 

FACT: There were two distinct, intense geomagnetic storms associated with this 

activity. The coronal mass ejections that created these storms made the Sun-Earth transit 

in ~ 19 hours, making their average speed at near 5 million mph. These may be the fastest 

transits since August 1972. The storms were ranked as number 6 and 15 on the Top 30 

Ap Geomagnetic Storm List, which dates back to 1932. 

FACT: For the first time this solar cycle, three major active sunspot regions populated 

the visible disk at the same time. At its largest, Region 486 was equivalent in size to over 

13 Earths, making it the largest sunspot group this cycle and the largest since November

1990. 

FACT: This activity occurred 3.5 years after the peak month of Solar Cycle 23 (April 

2000). 

FACT: NOAA/SEC staff participated in numerous teleconferences with dispatchers,

pilots, and airline safety personnel from major airlines. Airlines rerouted over a dozen 

flights due to HF/VHF communications problems and potential biological impacts of 

radiation storms. Airlines (both U.S. and foreign) made important route and/or altitude 

restrictions to flight operations during the solar activity. SEC information was an 

important part of their decision making process. 

FACT: Several satellites and deep space instruments were put into safe mode in 

response to storm predictions. 

FACT: The astronauts on the International Space Station (ISS) were directed to take 

shelter in the service module during the peak exposure intervals of the October 28-30 

radiation storms. NASA also stowed the 56-foot-long Space Station Remote Manipulator 

System (robotic arm) during this period to prevent damage to this billion-dollar 

instrument. 

FACT: Operators in at least 13 nuclear power reactors took precautionary actions to 

mitigate the impacts of geomagnetically induced currents during geomagnetic storms. 

31
They expressed their appreciation to NOAA for helping them to counter the potential 

impacts and emphasized the importance of SEC data during extreme storming periods. 

FACT: The Space Weather Operations (SWO) alone logged over 300 media contacts 

from agencies around the world. SEC representatives participated in numerous live radio 

and TV interviews. Solar activity stories were sent over every major news agency. 

FACT: SEC issued four Space Weather Advisory Bulletins and assisted with eight 

NOAA Press Releases between October 22 – November 06. 

FACT: For the first time ever, the Federal Aviation Administration issued an advisory 

suggesting that airline pilots fly at lower altitudes when traveling above 35 degrees 

latitude, both north and south. This was in response to the strong – severe radiation 

storms that began on October 28. 

FACT: In late October, SEC’s web site usage increased from the average 0.5 million 

hits per day, to around 3 million hits per day. The site received over 19 million hits on 

October 29. 

32
Findings and Recommendations of the Assessment Team 

Observations 

Finding: The coronagraph proved to be an invaluable tool during this high solar activity 

period. Currently, there is no coronagraph instrument dedicated to real-time operational 

use. Those periods when LASCO coronagraph data were not available seriously limited 

NOAA/SEC’s ability to accurately assess and predict a rapidly changing space weather 

environment. 

Recommendation: NOAA should make the coronagraph a baseline instrument on future 

GOES spacecraft or other space-based platform. If the coronagraph is not deployed as an 

operational instrument, NOAA will suffer degradation in its current capability to provide 

space weather alerts and warnings. 

Finding: The only way to forewarn about geomagnetic storms and to drive models of 

the magnetosphere is to use measurements of the solar wind upstream of Earth. The 

current source of these data is a NASA research satellite (ACE), which has already 

outlived its expected period of service, and will not be replaced by NASA. Certain 

operationally important sensors on this research satellite are rendered useless during 

moderate to large radiation storms, which seriously impacted SEC’s storm assessment 

and warning ability. When solar data are no longer available from ACE, storms will be 

detected only when they have arrived at Earth; there will be no possibility to give reliable 

warnings. 

Recommendation: NOAA should either procure, launch, operate, and acquire data from

a series of real-time solar wind monitors placed near the Sun-Earth line, or NOAA should 

buy such data from a commercial supplier. 

Internal and External Coordination 

Finding: Teleconferences were conducted between airline representatives and SEC staff 

on a daily basis. Some difficulty in the understanding of solar phenomena and 

interpretation of SEC products was evident. 

Recommendations 1a: Develop a website for the airline user community. Pending 

developments in the private sector, post the applicable services and explanations that 

apply to airline operational needs. 

Recommendations 2a: Provide training for airline staff and management. Best options 

are for SEC staff to visit airline companies and/or facilitate a workshop for all interested 

parties (airline personnel, FAA, DOT, medical, etc). 

33
Finding: The deluge of media contacts at times overwhelmed SEC staff. The response to 

media requests was performed in a professional and timely manner; however, it had the 

potential to interfere with SEC operations. 

Recommendation: Improve the SEC web page to better facilitate the needs of media 

and the NOAA Public Affairs Office. Make plain language forecasts, Space Weather 

Bulletins, Alerts, Watches, and Warnings readily available and easily accessible. This 

would help alleviate the distraction during high solar activity. 

Models and Guidance 

Finding: The current D-Region Absorption Prediction model does not provide a true 

overall representation of space weather effects on communications for airline operations. 

The D-Region plot only identifies the impact of solar flares on communications. The 

additional impact of radiation storms and geomagnetic storms is not depicted. This 

caused some confusion to the airlines when making their decisions to route flights, 

especially on high latitude routes. 

Recommendation: Pending developments in the private sector, improve the D-Region 

Absorption Plot to include impacts of radiation storms and geomagnetic storms on 

communications, or develop a product for airlines that would depict high latitude HF and 

VHF communication effects. 

Finding: The Major Event Database proved to be a very valuable statistical tool in 

estimating a geophysical response from large flares. The database and interactive tool are 

still being developed, but the limited information available was used extensively. 

Recommendation: Complete this database and interactive software and install in the 

Forecast Center. 

Finding: Significant shortfalls exist in warning and forecast capability due to inadequate 

models and tools to derive forecast products. There is currently limited capability to warn 

for solar flare radio blackouts, high energy radiation storms, and many other aspects of 

space weather. 

Recommendation: NOAA and SEC must assist in and support modeling efforts such as 

the Center for Integrated Space weather Modeling (CISM) and the Community 

Coordinated Modeling Center (CCMC) as well as other research and commercial 

institution modeling capabilities. Fully functional Rapid Prototyping Centers (RPCs), 

operations testbeds, or commercially outsourced engineering implementation contracts 

must be in place for rapid, focused development and transition of required models into 

Space Weather operations. The recent activity highlighted the need for the following 

models: 

34
 Coronal Mass Ejection Propagation - CME characterization (mass, speed, 

direction, and magnetic structure) for predicting time of CME arrival and 

onset and intensity of geomagnetic storming. 

 Solar Energetic Particles (SEP) - SEP spectra for airlines, satellite 

anomaly, and manned space flight hazard prediction. Airline companies 

and satellite operators requested more detailed SEP onset time and 

duration predictions. 

 Radiation Belt Particle distribution (>100 keV) for satellite upset 

prediction. Precipitating particle characterization (location, energy, 

timing) for polar ionosphere prediction. Requested by both government 

and commercial satellite companies. 

 Ionosphere - Global EDP for radar and communications signal path 

bending prediction. Global TEC for radar and communications signal path 

delay prediction. Global ionospheric currents for ionospheric event 

propagation prediction - A three-dimensional Global Assimilative 

Ionospheric Model (GAIM). This would help meet the communication 

needs identified by HF users including airlines. 

 Polar Scintillation - Arctic spatial and frequency distribution for 

communications, radar, and navigation signal corruption and outage 

prediction. Both DoD and commercial high latitude interests identified this 

need. 

 Neutral Environment - Global neutral density and composition (>90 km)

for accurate satellite, space debris, and missile orbit prediction. Global 

neutral winds (>90 km) for accurate communications, radar, and 

navigation signal corruption and outage prediction. Global neutral 

temperature (>90 km) for accurate communications, radar, and navigation

signal corruption and outage prediction. 

Warnings and Forecasts 

Finding: Customers have established radiation storm thresholds to mitigate potential 

impacts. SEC does not currently provide predictions of the maximum flux of a radiation 

storm. 

Recommendation: Utilize developments in modeling efforts, including those in the 

academic and vendor community, to provide improved radiation storm warnings to 

include maximum flux expected. 

35
Finding: SEC provides a daily forecast at 2100 UT. This forecast is not amended as 

conditions change during the day, and consequently, it can be used only as guidance and 

not as an operational tool. 

Recommendation: Establish requirements for amending the forecast or develop a new 

web-based dynamic forecast product. 

Dissemination 

Finding: The file transfer requests from the SEC web pages slowed our system after the 

first couple days of high solar activity. This halted processes, and as a result, many users 

attempting to access SEC’s web site during peak periods could not get in. It was resolved 

by configuring software and systems to begin mirroring SEC web site content on the 

NOAA Network Operations Center (NOC) Web Farm in Boulder, Colorado. 

Recommendation: Establish a permanent networking agreement with the NOC to 

continue this expanding service. 

36
Best Practices 

1. Maintaining Focus on the Space Environment 

Forecasters focused on the space environment in teleconferences with the airlines. 

Forecasters are not qualified to assess and predict the biological impacts of the high 

radiation storms. Varying opinions would only serve to confuse both the public and the 

airlines in regard to this issue. Appropriate references are available in the Forecast 

Center, and SEC staff routinely and consistently distributed this information. 

2. Media Management 

Management ensured additional staff members were on duty to handle the deluge 

of media interests in this solar activity outbreak. As a consequence, forecasters could 

concentrate on product generation and dissemination and maintain high quality customer 

support. 

3. Airline Teleconferences 

Additional staff members were also made available to support airline operations. 

Teleconferences were, on occasion, quite lengthy, and the duty forecaster could not 

afford to be involved in lengthy discussions. 

4. Daily Staff Meetings 

Daily operations meetings were initiated to ensure consistency among SEC staff. 

It was important for SEC staff to be aware of the rapidly changing space weather 

conditions when advising media and public alike. These meetings also gave the staff an 

opportunity to share their expertise and provide input to the forecasts and warnings. 

5. OAR Web Farm 

Switching over the overwhelmed SEC website to an OAR Web Farm in order to 

handle the volume of file transfers was critical. The web farm servers were available to 

mirror SEC’s website content to the public. 

6. SXI Activation 

SEC Operations submitted a formal request to NOAA and NESDIS management 

to resume SXI operations. The expedited request was immediately approved, and realtime SXI imagery was made available in the forecast center. 

37
BLANK PAGE

38
APPENDIX A 

NOAA SPACE WEATHER SCALES

39
APPENDIX A – NOAA SPACE WEATHER SCALES

Category Effect Physical

measure 

Average Freq. 

(1 cycle = 11 yr)

Scale Descriptor Duration of event will influence severity of effects 

Solar Radiation Storms 

Flux level 

of >= 10 

MeV 

particles 

(ions)* 

 

Number of 

events when

flux level was 

met ** 

S 5 Extreme Biological: unavoidable high radiation hazard to astronauts on EVA (extravehicular activity); high radiation exposure to passengers and crew in 

commercial jets at high latitudes (approximately 100 chest x-rays) is possible. 

Satellite operations: satellites may be rendered useless, memory impacts can

cause loss of control, may cause serious noise in image data, star-trackers may

be unable to locate sources; permanent damage to solar panels possible. 

Other systems: complete blackout of HF (high frequency) communications 

possible through the polar regions, and position errors make navigation

operations extremely difficult. 

105 Fewer than 1 per 

cycle 

S 4 Severe Biological: unavoidable radiation hazard to astronauts on EVA; elevated 

radiation exposure to passengers and crew in commercial jets at high latitudes 

(approximately 10 chest x-rays) is possible. 

Satellite operations: may experience memory device problems and noise on

imaging systems; star-tracker problems may cause orientation problems, and

solar panel efficiency can be degraded. 

Other systems: blackout of HF radio communications through the polar

regions and increased navigation errors over several days are likely. 

104 3 per cycle 

 

S 3 Strong Biological: radiation hazard avoidance recommended for astronauts on EVA; 

passengers and crew in commercial jets at high latitudes may receive low-level

radiation exposure (approximately 1 chest x-ray). 

Satellite operations: single-event upsets, noise in imaging systems, and slight 

reduction of efficiency in solar panel are likely. 

Other systems: degraded HF radio propagation through the polar regions and 

navigation position errors likely.

103 10 per cycle 

 

S 2 Moderate Biological: none. 

Satellite operations: infrequent single-event upsets possible. 

Other systems: small effects on HF propagation through the polar regions and 

navigation at polar cap locations possibly affected. 

102 25 per cycle 

S 1 Minor Biological: none. 

Satellite operations: none. 

Other systems: minor impacts on HF radio in the polar regions. 

10 50 per cycle 

* Flux levels are 5 minute averages. Flux in particles·s

-1·ster-1·cm-2. Based on this measure, but other physical measures

are also considered. 

** These events can last more than one day. 

40
APPENDIX A – NOAA SPACE WEATHER SCALES

Category Effect Physical

measure 

Average Freq. 

(1 cycle = 11 yrs) 

Scale Descriptor Duration of event will influence severity of effects 

Radio Blackouts 

GOES Xray peak 

brightness 

by class 

and by

flux* 

Number of events

when flux level 

was met 

R 5 Extreme HF Radio:Complete HF (high frequency**) radio blackout on the entire 

sunlit side of the Earth lasting for a number of hours. This results in no HF 

radio contact with mariners and en route aviators in this sector. 

Navigation: Low-frequency navigation signals used by maritime and general 

aviation systems experience outages on the sunlit side of the Earth for many

hours, causing loss in positioning. Increased satellite navigation errors in 

positioning for several hours on the sunlit side of Earth, which may spread

into the night side. 

X20 

(2 x 10-3) 

Less than 1 per 

cycle 

 

R 4 Severe HF Radio: : HF radio communication blackout on most of the sunlit side of

Earth for one to two hours. HF radio contact lost during this time. 

Navigation: Outages of low-frequency navigation signals cause increased

error in positioning for one to two hours. Minor disruptions of satellite 

navigation possible on the sunlit side of Earth. 

X10 

(10-3) 

8 per cycle 

(8 days per cycle) 

 

R 3 Strong HF Radio: Wide area blackout of HF radio communication, loss of radio

contact for about an hour on sunlit side of Earth. 

Navigation: Low-frequency navigation signals degraded for about an hour. 

X1 

(10-4) 

175 per cycle 

(140 days per 

cycle) 

R 2 Moderate HF Radio: Limited blackout of HF radio communication on sunlit side, loss 

of radio contact for tens of minutes. 

Navigation: Degradation of low-frequency navigation signals for tens of 

minutes. 

M5 

(5 x 10-5) 

350 per cycle 

(300 days per 

cycle) 

R 1 Minor HF Radio: Weak or minor degradation of HF radio communication on sunlit

side, occasional loss of radio contact. 

Navigation: Low-frequency navigation signals degraded for brief intervals. 

M1 

(10-5) 

2000 per cycle 

(950 days per 

cycle) 

* Flux, measured in the 0.1-0.8 nm range, in W·m-2. Based on this measure, but other physical measures are also

considered. 

** Other frequencies may also be affected by these conditions. 

41
APPENDIX A – NOAA SPACE WEATHER SCALES

Category Effect Physical

measure 

Average Freq.

(1 cycle = 11 yrs) 

Scale Descriptor Duration of event will influence severity of effects 

Geomagnetic Storms 

Kp values* 

determined

every 3 

hours 

Number of storm 

events when Kp

level was met 

G 5 Extreme Power systems: : widespread voltage control problems and protective

system problems can occur, some grid systems may experience complete 

collapse or blackouts. Transformers may experience damage. 

Spacecraft operations: may experience extensive surface charging, 

problems with orientation, uplink/downlink and tracking satellites. 

Other systems: pipeline currents can reach hundreds of amps, HF (high 

frequency) radio propagation may be impossible in many areas for one to 

two days, satellite navigation may be degraded for days, low-frequency

radio navigation can be out for hours, and aurora has been seen as low as

Florida and southern Texas (typically 40° geomagnetic lat.)**. 

Kp = 9 4 per cycle 

(4 days per cycle) 

G 4 Severe Power systems: possible widespread voltage control problems and some 

protective systems will mistakenly trip out key assets from the grid. 

Spacecraft operations: may experience surface charging and tracking 

problems, corrections may be needed for orientation problems. 

Other systems: induced pipeline currents affect preventive measures, HF

radio propagation sporadic, satellite navigation degraded for hours, lowfrequency radio navigation disrupted, and aurora has been seen as low as

Alabama and northern California (typically 45° geomagnetic lat.)**. 

Kp = 8,

including a 9- 

100 per cycle 

(60 days per cycle) 

G 3 Strong Power systems: voltage corrections may be required, false alarms

triggered on some protection devices. 

Spacecraft operations: surface charging may occur on satellite 

components, drag may increase on low-Earth-orbit satellites, and

corrections may be needed for orientation problems. 

Other systems: intermittent satellite navigation and low-frequency radio

navigation problems may occur, HF radio may be intermittent, and aurora

has been seen as low as Illinois and Oregon (typically 50° geomagnetic 

lat.)**. 

Kp = 7 200 per cycle 

(130 days per 

cycle) 

G 2 Moderate Power systems: high-latitude power systems may experience voltage 

alarms, long-duration storms may cause transformer damage. 

Spacecraft operations: corrective actions to orientation may be required

by ground control; possible changes in drag affect orbit predictions. 

Other systems: HF radio propagation can fade at higher latitudes, and 

aurora has been seen as low as New York and Idaho (typically 55°

geomagnetic lat.)**. 

Kp = 6 600 per cycle 

(360 days per 

cycle) 

G 1 Minor Power systems: weak power grid fluctuations can occur. 

Spacecraft operations: minor impact on satellite operations possible. 

Other systems: migratory animals are affected at this and higher levels;

aurora is commonly visible at high latitudes (northern Michigan and 

Maine)**. 

Kp = 5 1700 per cycle 

(900 days per 

cycle) 

* Based on this measure, but other physical measures are also considered. 

** For specific locations around the globe, use geomagnetic latitude to determine likely sightings. 

42
APPENDIX B 

X-RAY FLARE CLASSIFICATION 

The X-ray flare class is the rank of a flare based on its X-ray energy output. Flares 

are classified by the order of magnitude of the peak burst intensity (I) measured by the Xray sensor on GOES satellites in the 1 to 8 angstrom band as follows: 

 Class (in Watt/sq. Meter) 

 B I < 1.0E-06 

 C 1.0E-06 <= I <= 1.0E-05 

 M 1.0E-05 <= I <= 1.0E-04 

 X I >= 1.0E-04 

43
44
APPENDIX C 

EVENT STATISTICS 

Radio Blackouts 

 October November 

Days 19 20 21 22 23 24 25 26 27 28 29 30 31 01 02 03 04 05 06 07

Intensity R3 R1 R2 R2 R3 R2 R1 R3 R2 R4 R4 R1 R1 R1 R3 R3 R5 R2 

 Number of Days with Radio Blackouts: 18 

 Number of Alerts (>R1): 17

NOTE 1: Warnings are not issued for Radio Blackouts 

Geomagnetic Storms 

 

 Number of Days with Storming: 12 

 Number of Watches Issued: 14 

 Number of Warnings Issued: 12 

 Number of Alerts Issued: 41 

 Avg Leadtime: 14 mins 

 Avg Leadtime for G2-G5 Warnings: 21 mins 

 False alarm rate: 20%

 Missed warnings: 1

Days 19 20 21 22 23 24 25 26 27 28 29 30 31 01 02 03 04 05 06 07

Intensity G1 G2 G2 G1 G3 G1 G5 G5 G4 G1 G3 G1 

 October November 

45
Radiation Storms 

Days 19 20 21 22 23 24 25 26 27 28 29 30 31 01 02 03 04 05 06 07

Intensity S2 S2 S3 S4 S3 S2 S1 S2 S3 S2 S2 S1 S1

Number of Radiation Storm Days: 13 

Number of Warnings Issued: 4 

Number of Alerts Issued: 31 

Avg Leadtime: 195 mins 

False Alarm Rate: 0%

Missed Warnings: 0 

 October November 

NOTE 1: Intensity is highest storming level for each day, i.e., the S4 storm on October 29 began on October 28, 

but did not reach the S4 level until October 29. 

NOTE 2: Eleven additional radiation storm warnings were issued, but all were continuations of existing warnings.

NOTE 3: Lead times on the four radiation storm warnings ranged from 14 minutes to 10 hours. 

.

46
APPENDIX D 

HISTORICAL PERSPECTIVE 

Top 30 Geomagnetic Storms

(Potsdam Running Ap - since 1932) 

Rank Intensity Date Rank Intensity Date

 1 312 09/18/1941 16 220 10/30/2003

 2 293 11/12/1960 17 216 07/08/1958 

 3 285 03/13/1989 18 215 03/28/1946 

 4 277 03/23/1940 19 214 09/22/1946 

 5 258 10/04/1960 20 212 03/01/1941 

 6 252 10/29/2003 21 212 07/26/1946 

 7 252 07/15/1959 22 203 08/19/1950 

 8 251 03/31/1960 23 201 09/04/1982 

 9 241 05/25/1967 24 199 02/07/1946 

 10 229 07/11/1982 25 199 02/11/1958 

 11 228 02/07/1986 26 196 05/12/1949 

 12 226 03/29/1940 27 196 06/04/1991 

 13 223 08/04/1972 28 195 03/24/1946 

 14 222 07/05/1941 29 193 05/09/1992 

 15 221 09/02/1957 30 192 07/14/2000 

NOTE: Potsdam, Germany, is the official world center for the Ap geomagnetic indices. 

47
Top 20 Radiation Storms

(NOAA GOES >10 MeV Proton Data - since 1976)

 

Rank Intensity Date Rank Intensity Date

 (pfu) (pfu) 

1 43,000 03/23/1991 11 7,300 11/30/1989 

2 40,000 10/19/1989 12 4,600 05/09/1982 

3 31,700 11/04/2001 13 4,500 09/29/1989

4 29,500 10/28/2003 14 3,500 03/08/1989 

5 24,000 07/14/2000 15 3,000 06/04/1991 

6 18,900 11/22/2001 16 2,900 06/11/1982 

7 14,800 11/08/2000 17 2,700 10/30/1992 

8 12,900 09/24/2001 18 2,520 04/21/2002 

9 10,000 02/20/1994 19 2,500 04/25/1984 

 10 9,200 08/12/1989 20 2,360 10/01/2001 

NOTE: The X10 flare on October 29 produced a peak of 3300 pfu on October 30, but this 

new peak occurred in the waning stages of the October 28, 29,500 pfu radiation storm. 

Overlapping radiation storms are identified on this list as one storm. 

 Top Solar Flares

(NOAA GOES X-ray Flares - since 1976)

Date X-ray Region Date X-ray Region

 11/04/03 X28e 486 12/15/82 X12 4026

 08/16/89 X20e 5629 06/04/91 X12e 6659 

 04/02/01 X20e 9393 06/06/91 X12e 6659 

 10/28/03 X17 486 06/11/91 X12e 6659

 07/11/78 X15e 1203 06/15/91 X12e 6659 

 03/06/89 X15e 5395 12/17/82 X10 4025 

 04/24/84 X13e 4474 05/20/84 X10 4492 

 10/19/89 X13e 5747 01/25/91 X10 6471 

 06/06/82 X12e 3763 06/09/91 X10 6659 

 06/01/91 X12e 6659 10/29/03 X10 486

 

NOTE: Flares with an “e” suffix are estimated due to saturation of the GOES XRS 

instrument. The saturation level was increased to X17.4 in 1993.

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