Pentagon Fuel Use, Climate Change, and the Costs of War
Neta C. Crawford1
Boston University
June 12, 2019
Summary
In its quest for security, the United States spends more on the military than any othercountry in the world, certainly much more than the combined military spending of its
major rivals, Russia and China. Authorized at over $700 billion in Fiscal Year 2019, andagain over $700 billion requested for FY2020, the Department of Defense (DOD) budget
comprises more than half of all federal discretionary spending each year. With an armed
force of more than two million people, 11 nuclear aircraft carriers, and the most advanced
military aircraft, the US is more than capable of projecting power anywhere in the globe,
and with “Space Command,” into outer-space. Further, the US has been continuously at war
since late 2001, with the US military and State Department currently engaged in more than
80 countries in counterterror operations.2
All this capacity for and use of military force requires a great deal of energy, most of itin the form of fossil fuel. As General David Petraeus said in 2011, “Energy is the lifeblood of
our warfighting capabilities.”3 Although the Pentagon has, in recent years, increasingly
emphasized what it calls energy security — energy resilience and conservation — it is stilla significant consumer of fossil fuel energy. Indeed, the DOD is the world’s largest

1 Neta C. Crawford is Professor of Political Science at Boston University and Co-Director of the Costs of War

project. Crawford thanks Matthew Evangelista, Anna Henchman, Catherine Lutz, Nathan Phillips, Stephanie
Savell, Adam Sweeting, and Alexander Thompson for their critical comments and helpful suggestions on an
earlier draft of this paper. Crawford also benefited from feedback at Ohio State University in April 2019.
2 Crawford has previously estimated that the budgetary costs of the post-9/11 wars, including Homeland
Security and our future obligations to care for the veterans of these wars, are nearly $6 trillion dollars. Neta
C. Crawford, “United States Budgetary Costs of the Post-9/11 Wars Through FY2019: $5.9 Trillion Spent andObligated,” Costs of War Project, November 2018.
https://watson.brown.edu/costsofwar/files/cow/imce/papers/2018/Crawford_Costs%20of%20War%20Es
timates%20Through%20FY2019.pdf.
3 General David Petraeus, quoted in Department of Energy, “Energy for the Warfighter: The Department of
Defense Operational Energy Strategy,” 14 June 2011, https://www.energy.gov/articles/energy-war-fighterdepartment-defense-operational-energy-strategy.

1

institutional user of petroleum and correspondingly, the single largest producer ofgreenhouse gases (GHG) in the world.4
This paper specifically examines military fuel usage for the US post-9/11 wars and theimpact of that fuel usage on greenhouse gases emissions. The best estimate of US military
greenhouse gas emissions from 2001, when the wars began with the US invasion of
Afghanistan, through 2017, is that the US military has emitted 1,212 million metric tons ofgreenhouse gases (measured in CO2equivalent, or CO2e). In 2017, for example, thePentagon’s greenhouse gas emissions were greater than the greenhouse gas emissions ofentire industrialized countries as Sweden or Denmark.
DOD emissions for all military operations from 2001 to 2017 are estimated to be about
766 million metric tons of CO2e. And of these military operations, it is estimated that total
war-related emissions including for the “overseas contingency operations” in the major
war zones of Afghanistan, Pakistan, Iraq and Syria,5 are more than 400 Million Metric Tons
of CO2e.
The US military is preparing for threats of attack from human adversaries. The threatsof terrorism, Russian, Iranian, Chinese or Korean aggression are all real, but terrorists andthese countries are not certain to attack the US. Arms control and diplomacy can deescalate
tensions and reduce threats. Economic sanctions can also diminish the capacity of states
and non-state actors to threaten the security interests of the US and its allies.
Global warming is the most certain and immediate of any of the threats that the US
faces in the next several decades. In fact, global warming has begun: drought, fire, flooding,and temperature extremes that will lead to displacement and death. The effects of climatechange, including extremely powerful storms, famine and diminished access to fresh water,
will likely make regions of the world unstable — feeding political tensions and fueling massmigrations and refugee crises. In response, the military has added the national security
implications of climate change to its long list of national security concerns.
Unlike some elements of the present US administration, which is in various modes ofclimate denial, the US military and intelligence community act as if the negative security
consequences of a warming planet are inevitable. The DOD has studied the problem for
decades and begun to adapt its plans, operations and installations to deal with climatechange.
The US military has an opportunity to reduce the risks associated with climate change— and the security threats associated with climate change — by reducing their role in
4 These emissions are a result not only of war, but also of on-going non-war operations and maintenance ofmilitary installations. For a discussion of the concept of greenhouse gas equivalencies, see Appendix 1. Also
see https://www.epa.gov/energy/greenhouse-gas-equivalencies-calculator.
5 See Appendix 1. This is a conservative estimate. Not including biogenic sources or reductions fromrenewable energy use; the latter were less than 1 percent of emissions. In the most recent year for which
statistics are available, total greenhouse gas emissions by the DOD for FY2017 were about 58.4 million metrictons of CO2 equivalent.

2creating greenhouse gas emissions. While some sea level rise and mass extinction willcertainly occur — these changes have already begun — the most dire consequences ofclimate change and the associated threats and consequences to national security are notalready baked into the system.6 There is time to act to reduce greenhouse gas emissions
and it is urgent to do so. If the US military were to significantly decrease its greenhouse gas
emissions it would make the dire climate change caused national security threats the US
military fears and predicts less likely to occur.
Part I of this paper outlines the scale and pattern of US military fuel use, including theoil that the US uses to protect access to Persian Gulf oil. Part II estimates greenhouse gas
emissions by the US military and the portion of those emissions that are a consequence ofthe major post-9/11 US wars. The US military has begun greenhouse gas emissions
reductions, but there is room for much steeper cuts. For readers interested in further
detail, Appendix 1 elaborates on technical issues and summarizes the sources of data andassumptions for the best estimates of greenhouse gas emissions the US has made in war
from 2001 to 2017.
Part III of the paper summarizes the way the US military understands the national
security implications of the military’s oil dependency and climate change. The Pentagon
views climate change as a threat to military installations and operations, as well as tonational security, when and if climate change leads mass migration, conflict and war. Yet
the Pentagon does not acknowledge that its own fuel use is a major contributor to climatechange. The military uses a great deal of fossil fuel protecting access to Persian Gulf Oil.
Because the current trend is that the US is becoming less dependent on oil, it may be thatthe mission of protecting Persian Gulf oil is no longer vital and the US military can reduce
its presence in the Persian Gulf. The Pentagon can also reduce US military greenhouse gas
emissions in other ways. These alternatives are discussed more in Appendix 2, whichsuggests specific measures Congress might consider to reduce DOD fossil fuel consumption.
Absent any change in US military fuel use policy, the fuel consumption of the US military
will necessarily continue to generate high levels of greenhouse gases. These greenhousegases, combined with other US emissions, will help guarantee the nightmare scenarios thatthe military predicts and that many climate scientists say are possible.
Reductions in military fossil fuel use would be beneficial in four ways. First, the US
would reduce greenhouse gas emissions. This would thereby mitigate climate change andits associated threats to national security. Second, reducing fossil fuel consumption would
have important political and security benefits, including reducing the dependence of troops
in the field on oil, which the military acknowledges makes them vulnerable to enemy
attacks. If the US military were to significantly decrease its dependence on oil, the US could
reduce the political and fuel resources it uses to defend access to oil, particularly in the
Persian Gulf, where it concentrates these efforts. Third, by decreasing US dependence on
6 Keeping global warming to less than 1.5°C yields a much more livable planet than if the climate warms morethan that. Intergovernmental Panel on Climate Change (IPCC), “Global Warming of 1.5°C,” Summary for
Policymakers, (Switzerland: IPCC, 2018).

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oil-rich states the US could then reevaluate the size of the US military presence in the
Persian Gulf and reevaluate its relationship with Saudi Arabia and other allies in the region.
Finally, by spending less money on fuel and operations to provide secure access topetroleum, the US could decrease its military spending and reorient the economy to more
economically productive activities.
I. US Military Energy Consumption and Fuel
War and preparation for it are fossil fuel intensive activities. The US military’s energy
consumption drives total US government energy consumption. The DOD is the single
largest consumer of energy in the US, and in fact, the world’s single largest institutional
consumer of petroleum.
Figure 1 tracks US Federal government energy use. From 1975 until 1990, the energy
consumed by the DOD was essentially steady. During the 1991 Gulf War, US alliancepartners, namely Saudi Arabia, provided much of the fuel used in that war. After the 1991
Gulf War, and with the end of the Cold War, US military energy consumption declined until
the 9/11 attacks. In 2001, as a consequence of beginning a major war in Afghanistan,energy consumption by the DOD increased, and in 2005 hit its highest level in a decade.
Since 2001, the DOD has consistently consumed between 77 and 80 percent of all US
government energy consumption.

Trillions of British Thermal
Units (BTUs)

Figure 1. DOD and Total US Federal Government Energy Consumption, 1975-2017, in
BTUs7
2000
1500
1000
500
0
U.S. Department of Defense Consumption

U.S. Government Total Consumption

7 In Trillions of British Thermal Units. Source of data: US Energy Information Administration.

https://www.eia.gov/totalenergy/data/monthly/dataunits.php.

4Since the 2007 Energy Independence and Security Act the US government has
gradually decreased its overall energy use.8 Only in FY2013 did DOD energy consumption
return to the level it was in 2000. The headline from the Energy Information
Administration announcing the transition said “Defense Department Energy Use Falls to
Lowest Level Since 1975.”9 Yet, even as it has realized significant reductions in fossil fueluse, the Pentagon’s consumption remains high. Indeed, the military annually consumes
more fuel than most countries.
As the next figure illustrates, jet fuel, diesel fuel, and electricity production are thelargest elements of DOD, and therefore US government, energy consumption.
Figure 2. Categories of Energy Consumed by the US Government and DOD10

Why does the US military consume so much energy? It’s fighting “tooth” employs
equipment that guzzles fuel at an incredible rate. The logistical “tail” and the installations
that support operations are also extremely fuel intensive. Even the military’s non-armoredvehicles are notoriously inefficient. For instance, the approximately 60,000 HUMVEEs
remaining in the US Army fleet get between four to eight miles per gallon of diesel fuel.11

8 Energy Independence and Security Act of 2007, https://www.govinfo.gov/content/pkg/BILLS-

110hr6enr/pdf/BILLS-110hr6enr.pdf/. See the Department of Defense, “Operational Energy Strategy:
Implementation Plan,” March 2012https://www.globalsecurity.org/military/library/policy/dod/operational-energy-strategy_implementationplan201203.pdf.
9 US Energy Information System, “Defense Department Energy Use Falls to Lowest Level Since 1975.”
https://www.eia.gov/todayinenergy/detail.php?id=19871.
10 Source: U.S. Energy Information Administration, “U.S. Federal Government Energy Costs at Lowest Point
Since Fiscal Year 2004,” 2 October 2017, https://www.eia.gov/todayinenergy/detail.php?id=33152. Overall,gasoline led total US petroleum consumption, followed by diesel fuel and home heating oil, and natural gases(HGLs) of various types.
11 Daniel Gouré, “The U.S Army’s All-But Forgotten Vehicle Fleet,” Real Clear Defense, 22 August 2017,https://www.realcleardefense.com/articles/2017/08/22/the_us_armys_allbut_forgotten_vehicle_fleet_112116.html. The gas hungry Ford F-150 pickup truck gets 17 miles per gallon in
the city; the hungrier Chevrolet Suburban gets 15 miles per gallon in the city.

5Installation and Operational Energy Use
The DOD tracks its energy consumption in two baskets. Energy usage for installations isabout 30 percent of Pentagon consumption. Although these military installations in the US
and abroad necessarily support operations, the DOD tracks installation energy use
separately.12 But, as the Pentagon notes, “In many ways, installation energy supports
warfighter requirements through secure and resilient sources of commercial electricalenergy, and where applicable, energy generation and storage, to support mission loads,
power projection platforms, remotely piloted aircraft operations, intelligence support, andcyber operations.”13
The installation tail that supports US operations and power projection capability
includes more than 560,000 buildings at about 500 installations, located on over 27 million
acres of land in the US and across the globe.14 In FY2017, the DOD spent $3.5 billion to heat,cool, and provide electricity to its facilities, down from the previous year, when it spent$3.7 billion.15 Each installation, of course, can produce greenhouse gas emissions. The
Pentagon building itself emitted 24,620.55 metric tons of CO2e in 2013.16
Despite the fact that in May 2018 the Trump administration rescinded the Obamaadministration’s federal energy efficiency goals, the DOD remains committed to reducing
its energy consumption for pragmatic reasons.17 The Pentagon and each service branchhave multiple projects underway to reduce installation energy use and the overall trend ininstallation consumption over the last ten years has been downward. Efforts to decreaseenergy consumption at installations include gradually replacing some non-tactical fleet
vehicles with hybrid, plug in hybrid and alternative fuel vehicles, reducing engine idling,developing solar installations at some forts and bases, and concluding power purchaseagreements for wind and solar energy.18 These efforts have borne fruit, but there the US
military has room for more reductions.

12 Office of the Assistant Secretary of Defense for Sustainment, “Installation Energy,”

https://www.acq.osd.mil/eie/IE/FEP_index.html.
Department of Defense, “2016 Operational Energy Strategy,”
https://www.acq.osd.mil/eie/Downloads/OE/2016%20OE%20Strategy_WEBd.pdf, p. 4.
14 Each installation consists of one or more sites, which may or may not be located contiguous to theinstallation.
15 Statement of Honorable Lucian Niemeyer, Assistant Secretary of Defense, Energy, Installations andEnvironment, before the Senate Committee on Appropriations, Subcommittee on Military Construction,
Veterans Affairs, and Related Agencies,” 26 April 2018, p. 13.
https://www.acq.osd.mil/eie/Downloads/Testimony/FY19%20EI&E%20Posture%20Statement%20%20SAC-M.pdf. See Office of the Assistant Secretary of Defense for Energy, Installations, and Environment,“Department of Defense Annual Energy Management and Resilience (AEMR) Report, Fiscal Year 2016, (July
2017) p. 15. https://www.acq.osd.mil/eie/Downloads/IE/FY%202016%20AEMR.pdf.
16 See the EPA, https://www.epa.gov/ghgreporting/ghg-reporting-program-data-sets.
17 Executive Order 13693 of 19 March 2015 “Planning for Federal Sustainability in the Next Decade” wasrevoked by President Trump with Executive Order 13834 on 17 May 2018. See
https://www.fedcenter.gov/programs/eo13834/ and https://www.fedcenter.gov/programs/eo13693/.
18 The Department of Defense Energy Performance Master Plan was developed in FY2011.

6

As figure 3 below shows, while the Army is the most energy intensive at its
installations, energy consumption at installations is relatively equally shared by theservices.
Figure 3. DOD Installation Energy Consumption, in BTUs, by Service19

The profile of fossil fuel energy consumption looks different when we consider“operational” energy. Operational energy use, defined as the energy “required for training,
moving, and sustaining military forces and weapons platforms” accounts for 70 percent of
DOD energy consumption.20 Most operational energy consumed is in the form of “bulk fuel”
purchases of jet (JP-8 and JP-5) and diesel fuel.21 Operational use varies, of course,
depending on what the US military is doing in any particular year — its ongoing andoccasional missions. When the US is engaged in war, as one would expect, consumption of
jet and diesel fuels increase. Their ratio will depend on the types of operations the militaryis performing — whether the war or particular phase of the war is land or air intensive.

19 Source: “Figure 4.1: FY2017 Installation Energy (Goal Subject) Consumption by Military Service,” from the

Office of the Assistant Secretary of Defense for Energy, Installations, and Environment, “Department of
Defense Annual Energy Management and Resilience (AEMR) Report, Fiscal Year 2017, (July 2018) p. 12.
20 Department of Defense, “Operational Energy,” https://www.acq.osd.mil/eie/OE/OE_index.html.
21 The services may purchase fuel locally and be reimbursed by the Defense Logistics Agency. United States
General Accountability Office, “Bulk Fuel: Actions Needed to Improve DOD’s Fuel Consumption Budget Data”(GAO-16-664) (September 2016), p. 6. https://www.gao.gov/assets/680/679682.pdf.

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The figure below shows operational energy use in FY2014, when DOD operational
consumption was 87.4 million barrels of petroleum. Jet fuel consumption by all the armed
services accounted for more than 70 percent of operational energy use that year. Although
all services have aircraft, the Air Force is the largest user of petroleum jet fuel among thearmed services. In 2014, the US was largely absent from Iraq, had reduced its forces in
Afghanistan, and began its war against ISIS in Syria, which started in August 2014 with air
strikes.
Figure 4. Operational Energy Use by Domain and Mission, FY201422

Because operational fuel use is greater than for installation fuel use, the US spends
more on it. In FY2017 the DOD consumed over 85 million barrels of operational fuel topower ships, aircraft, combat vehicles, and contingency bases at a cost of nearly $8.2
billion.23
22 Department of Defense, “2016 Operational Energy Strategy,”

https://www.acq.osd.mil/eie/Downloads/OE/2016%20OE%20Strategy_WEBd.pdf, p. 4.
23 Office of the Assistant Secretary of Defense for Sustainment. The DOD notes that “Traditionally, the scope ofoperational energy excludes nuclear energy used for the propulsion of the U.S. Navy’s aircraft carriers andsubmarines, as well as the energy used for military space launch and operations. Operational energy does
include the energy needed to operate the carrier’s embarked aircraft and helicopters.” Department of Defense,“Operational Energy,” [emphasis in the original] https://www.acq.osd.mil/eie/OE/OE_index.html. The US
Navy uses more than 180 nuclear reactors to power over 140 submarines and surface ships including all 11
US aircraft carriers and 70 submarines. See Department of the Navy, “United States Naval Nuclear Propulsion
Program,” September 2017.
https://www.energy.gov/sites/prod/files/migrated/nnsa/2018/01/f46/united_states_naval_nuclear_propul

8

Operational fuel consumption varies more than installation fuel use. For example,
operational fuel consumption in FY2017 was lower than in FY2016.24
Unsurprisingly then, total US military fuel consumption tracks US engagement in wars
and occupations. All told, from 1998 to 2017 the US purchased 2.4 billion barrels of
petroleum fuel.25 Since the 9/11 attacks, annual fuel purchases have averaged more than
120 million barrels of all types of fuel. Between 2010 and 2015, the armed services
purchased an average of 102 million barrels of fuel per year from the DOD.26 Purchases
have declined in recent years as the US has reduced its operations in Iraq and Afghanistan,
averaging about 100 million barrels a year from 2013-2017.

Millions of Barrels Purchased

Figure 5. Defense Logistics Petroleum Product Purchases in Millions of Barrels,
FY1998 - FY201727
200
100
0
19981999200020012002200320042005200620072008200920102011201220132014201520162017

Jet Fuel, all types
DieselTotal Petroleum Purchases, including othersion_program_operating_naval_nuclear_propulsion_plants_and_shipping_rail_naval_spent_fuel_safely_for_over_sixty_years.pdf.
24 In FY2016 the DOD consumed about 86 million barrels of fuel for operational purposes. Office ofUndersecretary of Defense for Acquisition, Technology and Logistics, “Fiscal Year 2016 Operational Energy
Annual Report,” https://www.acq.osd.mil/eie/Downloads/OE/FY16%20OE%20Annual%20Report.pdf.
25 The 1999 spike in jet fuel purchases corresponds with the 78-day NATO air war in Kosovo to which the US
contributed more than 500 aircraft. For statistics on the US role, see
https://www.afhistory.af.mil/FAQs/Fact-Sheets/Article/458957/operation-allied-force/.
26 The DOD thus likely itself emitted an average of 44 million metric tons of CO2 from burning petroleum per
year for this period from oil use alone. GAO, “Bulk Fuel: Actions Needed to Improve DOD’s Fuel Consumption
Budget Data,” p. 9. Carbon emissions per barrel of oil are 0.43 metric tons. See US Environmental Protection
Agency, Greenhouse Gases Equivalencies Calculator, https://www.epa.gov/energy/greenhouse-gasesequivalencies-calculator-calculations-and-references. (The average heat content of crude oil is 5.80 mmbtu
per barrel (EPA 2018). The average carbon coefficient of crude oil is 20.31 kg carbon per mmbtu (EPA 2018).
The fraction oxidized is 100 percent. 5.80 mmbtu/barrel × 20.31 kg C/mmbtu × 44 kg CO2/12 kg C × 1 metricton/1,000 kg = 0.43 metric tons CO2/barrel.)
27 Source of Data: Reports by the Department of Defense various years. For FY2017, see Defense Logistics
Agency- Energy,
https://www.dla.mil/Portals/104/Documents/Energy/Publications/E_Fiscal2017FactBookLowRes2.pdf?ver=2018-03-29-073051-897. Defense Energy Support Center, DESC, renamed the Defense Logistics AgencyEnergy in FY2010. Also see https://www.dla.mil/Energy/About/Library/Publications/. Also see Thomas P.
Frazier, et al, “Fuel Price Effects on Readiness,” Institute for Defense Analysis, May 2014, p. C-2.
https://www.ida.org/~/media/Corporate/Files/Publications/IDA.../P-5087.ashx.

9

The DOD does not report fuel consumption information to Congress in its annual
budget requests. Indeed, although the Pentagon calculates fuel consumption for internal
planning purposes, this information is explicitly withheld by the DOD in its reporting toCongress.28 The Department of Energy, however, does report the fuel consumption data formobile vehicle emissions by the US military from 1975 to 2017. Figure 6 illustrates the mix
of fossil fuels, by type from 1975 to 2017.29
Figure 6. DOD Vehicle Fuel Consumption, 1975-2017, in Millions of Gallons30
NAVY SPECIAL FUEL

6,329
181,436

JET FUELAVIATION GAS

592

LPG/ PROPANE

1437,918

DIESELGASOLINE

6,296

II. Estimating US Military Greenhouse Gas Emissions and Effects of Recent Wars
How much greenhouse gas does the US military emit, and how are those emissions
distributed between base and overseas contingency operations? There are many sources ofgreenhouse gases related to war and preparation for it. Specifically, there are seven major
sources of greenhouse gas emissions one could consider.31

28 Actual and estimated future petroleum, oil and lubricants consumption and costs for aircraft are analyzed

on the DOD’s OP-26A forms “POL Consumption and Costs” which explicitly states that fuel consumption data
is not to be shared with Congress: “The OP-26A exhibit will not be included in justification material
forwarded to Congress.” Emphasis in the original. Department of Defense, Comptroller, DOD Financial
Management Regulation, Chapter 3, p. 3-108.
https://comptroller.defense.gov/Portals/45/documents/fmr/archive/02aarch/02a_03old.pdf.
29 The US Air Force and Army use JP-8 fuel; the Navy uses JP-5 fuel. In 2017 jet fuel consumption accounted
for about 394 Trillion BTU. This was a slight decrease from the previous fiscal year, when it accounted forabout 398 trillion BTUs. See the US Department of Energy, Comprehensive Annual Energy Data andSustainability Performance,
http://ctsedwweb.ee.doe.gov/Annual/Report/SiteDeliveredEnergyUseAndCostBySectorAndTypeAndFiscalY
ear.aspx.
30 Data from the Department of Energy,
https://ctsedwweb.ee.doe.gov/Annual/Report/HistoricalFederalEnergyConsumptionDataByAgencyAndEnergyType
FY1975ToPresent.aspx. .
31 Biogenic emissions are excluded in these calculations. The Department of Energy does track these forrecent years.

101. Overall military emissions for installations and non-war operations.
2. War-related emissions by the US military in overseas contingency operations.
3. Emissions caused by US military industry — for instance, for production of weapons
and ammunition.
4. Emissions caused by the direct targeting of petroleum, namely the deliberateburning of oil wells and refineries by all parties.
5. Sources of emissions by other belligerents.
6. Energy consumed by reconstruction of damaged and destroyed infrastructure.
7. Emissions from other sources, such as fire suppression and extinguishing chemicals,
including Halon, a greenhouse gas, and from explosions and fires due to thedestruction of non-petroleum targets in warzones.
I focus here on the first two sources of military GHG emissions — overall military andwar-related emissions — and briefly discuss military industrial emissions.
Domestic and overseas military installations account for about 40 percent of DOD
greenhouse gas emissions.32 As we see from Figures 5 and 6 above, jet fuel is a major
component of US military fuel use and therefore of greenhouse gas emissions. During each
air mission, aircraft puts hundreds of tons of CO2 in the air, not to mention the support
activities of naval and ground based assets for these air missions. The US wars in
Afghanistan and Iraq began with days of massive airstrikes. Moreover, in each case,material was flown to the war zones and bases were set up to prosecute the wars andoccupations. Similarly, the US war against ISIS in Syria and Iraq, which began in August
2014 has entailed tens of thousands of aircraft sorties for various missions — fromreconnaissance, to airlift, refueling, and weapons strikes.33 A B-2 Bomber on a mission fromWhiteman Air Force Base in Missouri might be refueled many times. For example, on 18
January 2017, two B-2 B bombers, accompanied by 15 KC-135 and KC-10 aerial refuelingtankers made a 30 hour round trip mission from Whiteman Air Force Base to Libya to drop
bombs on ISIS targets in Libya.34
For purposes of illustration, Table 1, below, shows the capacities and relative fuelefficiency of several Air Force aircraft and emissions without aerial refueling. Note that thefuel economy of these aircraft is measured not in miles per gallon, but gallons per mile.35

32 Senate Appropriations Committee, Report (S. Rept. 112-168, 22 May 2012). Quoted in Moshe Schwartz,

Katherine Blakely, and Donald O’Rourke, “Department of Defense Energy Initiatives: Background Issues forCongress,” Congressional Research Service, 10 December 2012, p. 48.
33 See Data from US Central Command.
https://www.afcent.af.mil/Portals/82/Documents/Airpower%20summary/(U)%20APPROVED%20Dec%20
2018%20APS%20Data.pdf?ver=2019-02-08-022732-933.
34 See Tom Demerly, “All We Know About the U.S. B-2 Bombers 30-hour Round Trip Mission to Pound Daesh
in Libya,” The Aviationist, 29 January 2017. https://theaviationist.com/2017/01/20/all-we-know-about-theu-s-b-2-bombers-30-hour-round-trip-mission-to-pound-daesh-in-libya/.
35 Fuel use depends on the flight profile of the aircraft and other factors, such as load. By contrast withmilitary aircraft, a commercial Boeing 747 gets about 5 gallons per mile, and can carry over 500 passengers.

11

Table 1. Examples of US Military Aircraft Jet Fuel Consumption and CO2 Emissions36
Aircraft

MissionB-2

Bomber

F-35A(CTOL)
A-10

FighterbomberClose Air
Support
Refueling
Tanker

KC-135R

KC46A39

Internal
Fuel
Capacitypounds andin gallons37
167,000
lbs/
25,692 gal
18,499 lbs/
2,846 gal
11,000 lbs/
1,692 gal
50,000 lbs/
7,692 galRefueling EstimatedTanker
16,000 gal
and Cargo

Range innautical miles
on internal
fuel

Fuel
consumption,
gallons pernautical mile

Metric Tons ofCO2e Emissions,
without aerial
refueling.38

6,000

4.28
gallons/mile

251.4 Metric Tons

1,199

2.37
gallons/mile
3.38
gallons/mile
4.9
gallons/mile

27.8 Metric Tons

Estimated 2.9
gallons/mile

156.5 Metric Tons

500
1,500
(loaded with
150,000 lbs
of transfer
fuel)
6,385
(loaded with
210,000 lbs
of transfer
fuel)17.5 Metric Tons
75.3 Metric Tons

The Pentagon does not publicly and regularly report its fuel consumption or
greenhouse gas emissions, and there is no official publicly available DOD source for all
military greenhouse gas emissions. 40 It is possible, however, to estimate the overall
greenhouse gas of the US military using publicly available emissions data from the
Department of Energy for recent years, FY2008 and FY2010-2017 and fuel consumption

36 Calculated by the author from data about each aircraft. For instance, the B-2 carries 167,000 pounds of jet

fuel (almost 25,000 gallons) to travel 6,000 nautical miles (c. 6.900 miles) and is capable of mid-air refueling,taking on an additional 99,000 pounds of fuel at each refueling. The F-35A, with a combat radius estimated to
be about 584 nautical miles has an internal fuel capacity of 2,761 gallons. The A-10 has an internal fuelcapacity of 1,642 gallons of jet fuel has a combat radius of about 250 nautical miles.
37 Assuming each pound of jet fuel weighs an average of 6.5 pounds.
38 See the Appendix.
39 The KC-46A can refuel itself. Boeing has not released data on its internal fuel capacity. The estimate here
for fuel capacity and consumption is based on the Boeing 767-400ER range and fuel capacity.
40 Some have tried to estimate the greenhouse gas emissions of the Pentagon in war. See, for instance, Nikki
Reisch and Steve Kretzman, “A Climate of War: The War in Iraq and Global Warming,” Oil ChangeInternational (March 2008),
http://priceofoil.org/content/uploads/2008/03/A%20Climate%20of%20War%20FINAL%20(March%2017%202008).pdf.

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data for the period of 1975 to 2017. This data allows an estimate of how much of theseemissions may be attributable to war.
While the DOD categorizes its energy use into installations and operations, theDepartment of Energy uses different categories, dividing government departments CO2
equivalent emissions into three categories — standard operations, non-standard
operations and biogenic emissions.41 Because the paper focuses on greenhouse gas
emissions resulting from fossil fuel use, biogenic emissions are not included in theestimates; biogenic emissions are much smaller than standard and non-standard
emissions.
By Department of Energy definition, non-standard operations are “vehicles, vessels,
aircraft and other equipment used by Federal Government agencies in combat support,
combat service support, tactical or relief operations, training for such operations, law
enforcement, emergency response, or spaceflight (including associated ground-support
equipment). Non-Standard operations also include the generation of electric power
produced and sold commercially to other parties.”42 Standard operations appear to be
everything else that a department does to accomplish its functions, roles and missions. The
Department of Energy reports that the US DOD has produced a total (standard and nonstandard) of 527 million metric tons of CO2 equivalent from 2010 to 2017, an average ofabout 66 million metric tons per year in this period, roughly the same greenhouse gas
emissions of 14 million passenger cars driven for one year.43
Department of Energy data, were used to estimate the total greenhouse gas emissions
for standard and non-standard operations of the DOD from FY2001-2017 to be a total of
1,212 million metric tons of CO2 equivalent. In any one year, the Pentagon’s emissions are
greater than many smaller countries total greenhouse gas emissions. For example, in 2017,
US DOD greenhouse gas emissions were 59 million metric tons (not including biogenic
emissions) of CO2e. In that same year, Pentagon emissions were greater than Finland,
which emitted 46.8 million metric tons, Sweden which emitted 50.8 million metric tons,
and Denmark which emitted 33.5 million metric tons of CO2e.44

41 Department of Energy Federal Energy Management Program. Energy Information Agency, Comprehensive

Annual Energy Data and Sustainability Performance,
http://ctsedwweb.ee.doe.gov/Annual/Report/ComprehensiveGreenhouseGasGHGInventoriesByAgencyAndF
iscalYear.aspx. These categories do not correspond to the EPA Greenhouse Gas Inventory Reports, nor to the
DOD categories.
42 Besides the DOD, only the Department of Homeland Security performs a significant amount of “nonstandard operations.” Department of Energy,
https://ctsedwweb.ee.doe.gov/Annual/Report/ComprehensiveGreenhouseGasGHGInventoriesByAgencyAnd
FiscalYear.aspx.
43 There were about 268 million passenger vehicles in the US in 2016. See the EPA, passenger vehicles per
year, https://www.epa.gov/energy/greenhouse-gases-equivalencies-calculator-calculations-andreferences#vehicles.
44 M. Muntean, D. Guizzardi, et al, Fossil CO2 Emissions of All World Countries: 2018 Report (Joint ResearchCentre, European Commission, 2018) https://ec.europa.eu/jrc/en/publication/eur-scientific-and-technicalresearch-reports/fossil-co2-emissions-all-world-countries-2018-report13Figure 7. Estimate of DOD Greenhouse Gas Emissions, Millions of Metric Tons CO2efrom Total and Non-Standard DOD operations, 2001-201745
90
80

Millions of MT CO2e

70
60
50
40
30
20
10
-

2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017
Standard Emissions

Non-Standard Emissions

Total CO2e Emissions

How much of the total GHG emissions should be attributed to US post-9/11 wars? As
discussed in Appendix 1, there are various ways to estimate this. The estimate ofgreenhouse gas emissions in the major wars is based on the proportion of fuel use by
Central Command, which is the command responsible for operations in Afghanistan and
Iraq and Syria. In FY2014 (see figure 4) this was about 24 percent of the total non-standard
operational fuel consumption by the DOD. But because the US counterterror operations areunderway all over the world (in about 80-90 countries) the Central Command is not the
only war zone in the global war on terror. The portion of all greenhouse gas emissions
related to Central Command including overseas contingency operations, and the Global
War on Terror, is estimated to be about 35 percent of total greenhouse gas emissions fornon-standard and standard operations.
Table 2. Estimated DOD and War Related Overseas Contingency Operation
Greenhouse Gas Emissions, Millions of Metric Tons CO2e, 2001-201746

Standard
Non-standard (directly
support combat)
Total Emissions by Category

Total DOD CO2e
Emissionsin Millions of Metric
Tons
445
766
1,212

OCO-related CO2e
Emissionsin Millions of MetricTons
155.84268.21424.0645 Based on Department of Energy data. Methods are detailed in the Appendix.
46 Based on Department of Energy data.

14

The estimate above focuses on DOD emissions. Yet, a complete accounting of the total
emissions related to war and preparation for it, would include the GHG emissions ofmilitary industry. Military industry directly employs about 14.7 percent of all people in the
US manufacturing sector.47 Assuming that the relative size of direct employment in thedomestic US military industry is an indicator for the portion of the military industry in the
US industrial economy, the share of US greenhouse gas emissions from US based militaryindustry is estimated to be about 15 percent of total US industrial greenhouse gas
emissions.48 If half of those military related emissions are attributable to the post-9/11
wars, then US war manufacturing has emitted about 2,600 million megatons of CO2
equivalent greenhouse gas from 2001 to 2017, averaging 153 million metric tons of CO2eeach year.
Figure 8. Greenhouse Gases Attributable to Military Industry from 2001-201749

Millions of Metric Tons

350
300
250
200
150
100
50
0
2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017
GHG Attributed to Military Industry

Estimate of Military Industry GHG attributable to war

Finally, other emissions sources that are not calculated or estimated here may besignificant sources of greenhouse gasses. Specifically, it was not possible to estimate theemissions due to the burning of oil by sabotage and destruction of oil infrastructure by
47 In 2016, 839,171 people worked in US Defense Industries out of a total of 12,348,100 jobs total in the US

manufacturing sector. See Deloitte, “2017 Aerospace and Defense Sector Export and Labor Market Study,” p.
13. https://www2.deloitte.com/content/dam/Deloitte/us/Documents/manufacturing/us-2017-us-A&Dexports-and-labor-market-study.pdf and the US Bureau of Labor Statistics
https://www.bls.gov/emp/tables/employment-by-major-industry-sector.htm. Louis Uchitelle, “The U.S. Still
Leans on the Military-Industrial Complex,” The New York Times, 22 September 2017,https://www.nytimes.com/2017/09/22/business/economy/military-industrial-complex.html. In 1992,
about 14.4 percent of manufacturing jobs were in military industries. Ann Markeson and S. S. Costigan, eds.,
Arming the Future: A Defense Industry for the 21st Century (New York: Council on Foreign Relations, 1999) p.
341. Manufacturing accounts for most of the industrial sectors greenhouse gas emissions according to theannual EPA Inventory of U.S. Greenhouse Gases and Sinks, 1990-2017. The most recent is found athttps://www.epa.gov/sites/production/files/2019-02/documents/us-ghg-inventory-2019-main-text.pdf.
48 This does not include indirect jobs and therefore indirect military related emissions.
49 Calculated from U.S. Greenhouse Gas Emissions by Economic Sector with Electricity-Related Emissions
Distributed (MMT CO2Eq). EPA “Inventory of U.S. Greenhouse Gases and Sinks, 1990-2017.”

15

belligerents, the energy consumed by reconstruction, in particular in making cement, andemissions from other sources. Of these, the emissions from burning oil infrastructure in
Iraq and Syria may be the largest. In the 2003 invasion of Iraq, oil wells were set alight by
the Iraqi military and burned for several months.50 Oil infrastructure was targeted again in
2015, when the US bombed oil infrastructure in Iraq and Syria as a means of reducing ISIS
revenue. And when ISIS retreated, it set oil wells and pipelines on fire in Iraq and Syria.51 In
many cases, these fires burned for several months. For instance, starting in September
2014 the US targeted tanker trucks, and oil refinery and storage sites controlled by ISIS as ameans of cutting off their revenue stream. In October 2015, the US attacked more oil
producing ISIS controlled oil infrastructure.52 Further, NATO tankers were often attacked
by militants and burned during their transit through Pakistan into Afghanistan.
In addition, it would be possible, using the methods used here for US military
greenhouse gas emissions, to calculate the emissions of other belligerents. More than 60
countries joined the US in their war in Afghanistan, 37 fought with the US in the Iraq War,and more than 60 were allied with the US in the war against ISIS. These emissions may besubstantial.
In addition to accounting for greenhouse gas emissions, a full assessment of the climatechange consequences of war would include the loss of actual and future carbon
sequestration due to deforestation. Deforestation may occur as people displaced by war
use forests for shelter and fuel. In some wars, such as the US Civil War and the Vietnam
War, forests were deliberately burned to deprive adversaries of places to hide. In
Afghanistan, war caused migration and illegal logging appear to be the chief cause of
deforestation. The causes of deforestation in Iraq are complex but include war.53

50 Iraq did the same in the 1991 Gulf War, setting oil production facilities in Kuwait alight as they retreated. In

April and May 1991, an estimated 3 million barrels of oil were burning each day, 1 or 2 million tons of carbon
dioxide, or about 2 percent of worldwide CO2 emissions from fossil fuel and biomass. Congressional ResearchService, “The Environmental Impact of the Gulf War,” for the United States Senate Committee on Environment
and Public Works Gulf Pollution Task Force, March 1992, pp. 10 and 24. Out of the 82 million barrels releasedon land and at sea during the 1991 Gulf War, an estimated 11 million barrels of oil spilled into the Persian
Gulf, coating the coastlines of not only Kuwait, but other countries in the Gulf, including Saudi Arabia, andIran. More than a decade later, much of that oil remained in coastal areas. See Erich R. Gundlach, John C.
McCain, and Yusef H. Fadallah, “Distribution of Oil Along the Saudi Arabian Coastline (May/June 1991) as a
Result of the Gulf War Oil Spills,” Marine Pollution Bulletin, vol. 27, (1993) pp. 93-96. Dagmar Schmidt-Etkin,“Spill Occurrences: A World Overview,” in Mervin Fingas, ed., Oil Spill Science and Technology (Amsterdam:
Elsevier, 2011) p. 8 and Jacqueline Michel, “1991 Gulf War Oil Spill,” in Fingas, ed. Oil Spill Science andTechnology, pp. 1127-1132.
51 Saif Hameed and Dominic Evans, “Islamic State Torches Oil Field Near Tikrit as Militia Advances,” Reuters, 5March 2015, https://www.reuters.com/article/us-mideast-crisis-iraq-idUSKBN0M10Z420150305.
52 This was known as Operation Tidal Wave II. See Matthew Reed, “Blowing up the Islamic State’s Oil
Company,” Foreign Policy, 26 October 2016, https://foreignpolicy.com/2016/10/26/blowing-up-the-islamicstates-oil-company-isis-abu-sayyaf/.
53 Zabihullah Ghazi, “Afghanistan’s Forest Cover Illegally Stripped Away,” Environment New Service, 29 August
2013, https://ens-newswire.com/2013/08/29/afghanistans-forest-cover-illegally-stripped-away/. UN
Environment, “Salvaging Iraq’s Remaining Wilderness,” 10 July 2018.
https://www.unenvironment.org/news-and-stories/story/salvaging-iraqs-remaining-wilderness.

16III. National Security Threats Posed by Oil Dependency and Climate Change
Three national security concerns overlap. First, the US government has long been
concerned about dependency on Persian Gulf Oil. At the same time, some portion of themilitary’s operational fuel consumption is related to missions associated with protecting
access to oil and protecting the regimes that assure US and global access to oil. Some
believe this mission is vital, while others question whether it is still necessary. Whether or
not this mission is essential, operations to ensure access to oil are expensive, not tomention, fuel intensive. By one estimate, the annual incremental cost of US operations toprotect against threats against Persian Gulf oil is about $5 billion.54 By another estimate, ata minimum the US spends about $81 billion annually defending the global oil supply.55
Second, the DOD has become increasingly concerned that climate change poses threats
and challenges to the military as an institution, specifically to military installations andoperations. This is coupled with a concern that fuel dependency makes the US militaryvulnerable. The US has reduced fuel consumption so that it is less dependent on fossil fuel.
And third, the Pentagon is concerned with the threats climate change pose tointernational security, namely massive migration and potentially war. However, themilitary seems unaware of how much its efforts to protect access to Persian Gulf Oil, its
other military operations including war, and consumption at installations are a major
driver of greenhouse gas emissions, and therefore ultimately of climate change.
In sum, the DOD assumes that climate change will be a disaster for the institution andthe planet no matter what they do, even as they believe that they must continue to protect
access to Persian Gulf oil so that the US and the rest of the world can burn as much oil as it
wants at as low a price per barrel as possible. The Pentagon focuses their efforts on
adapting to climate change and preparing for climate caused insecurity, even as they
continue to ensure that Americans continue to have relatively inexpensive access toimported oil.
Protecting Persian Gulf Oil: Is this Still a Vital Mission?
The concern about access to oil is twofold. The US economy remains heavily reliant onoil. The military has defended against several scenarios regarding a cut-off of Persian Gulf
oil. The first scenario is the threat that a hostile power would gain control of oil in the
Persian Gulf — for instance by occupying Saudi Arabia and Kuwait or by blocking the Straitof Hormuz — and be able to control world supply and increase the price of oil. In responseto the first fear, the US created the Strategic Petroleum Reserve in 1975 and the Rapid
Deployment Force (RDF) in 1979, whose specific mission was to defend US interests in the
54 Eugene Gholz, “U.S. Spending on Its Military Commitments to the Persian Gulf,” in Charles L. Glaser andRosemary A. Kelanic, eds., Crude Strategy: Rethinking the U.S. Military Commitment to Defend Persian Gulf Oil(Washington, DC: Georgetown University Press, 2016), pp. 167-195.
55 Securing America’s Future Energy, “The Military Cost of Defending the Global Oil Supply,” 21 September,
2018, http://secureenergy.org/wp-content/uploads/2018/09/Military-Cost-of-Defending-the-Global-OilSupply.-Sep.-18.-2018.pdf.

17Middle East, including oil. In January 1983, when US commands were reorganized, the RDF
became US Central Command (CENTCOM).
Figure 9. Zones of US Military Commands

When Iraq invaded Kuwait in 1990, the Bush Administration reiterated the importanceof oil in the region in National Security Directive 45. “U.S. interests in the Persian Gulf arevital to the national security. These interests include access to oil and the security andstability of key friendly states in the region. The United States will defend its vital interestsin the area, through the use of U.S. military force if necessary and appropriate, against any
power with interests inimical to our own.”56 In 1991 the US evicted Iraq from Kuwait not
only because the Iraqi invasion of Kuwait was illegal, but also in part because it feared that
Iraq posed a threat to Saudi Arabia, and thus to American access to oil.
Since then, the US has stationed large numbers of troops in the Persian Gulf at Army,
Navy, and Air Force bases. The Afghan and Iraq wars increased the US presence in theregion, as well as US military petroleum consumption. In late 2008, in addition to theconcern that a local state might try to control the flow of oil from the Persian Gulf,
President George W. Bush added the concern that extremists might control oil and try to
blackmail the US: “You can imagine them saying, ‘We’re going to pull a bunch of oil off themarket to run your price of oil up unless you do the following. And the following would bealong the lines of, well, ‘Retreat and let us continue to expand our dark vision.’"57
The idea that the US has to protect the global flow of oil, and more specifically oil fromthe Persian Gulf, has largely been taken for granted by the US military and national security
56 National Security Directive 45, 20 August 1990, https://fas.org/irp/offdocs/nsd/nsd_45.htm.

57 Peter Baker, “Bush Says U.S. Pullout Would Let Radicals Use Oil as a Weapon,” Washington Post, 5

November 2006. http://www.washingtonpost.com/wpdyn/content/article/2006/11/04/AR2006110401025.html.

18

experts. A report by the Council on Foreign Relations noted in 2006, “Until very low levelsof dependence are reached, the United States and all other consumers of oil will depend on
the Persian Gulf.”58
Perhaps in part because dependence on Persian Gulf oil has declined significantly since2006, some analysts have recently questioned whether the large US presence in the Persian
Gulf region, and the infrastructure in Europe that supports it, is necessary.59 The argument
is that the US is less dependent on Persian Gulf oil than in the past, that price shocks will
not necessarily be as severe if oil flows were disrupted, and that even if a single country
controlled supplies, they would still want to sell the oil. The exception to the latter is Iraq,
which burned Kuwaiti Oil fields when they retreated from Kuwait in 1991 and the IslamicState, which burned oil facilities as they retreated from 2015-2018. In any case, theargument goes, even if the US were completely absent from the Gulf, the US could return to
the Gulf and restore oil flow at some later point. US forces in the region have alreadydeclined from their peak of about 230,000 troops in 2008.60
What would happen in the worst-case scenario — if oil flows from the Persian Gulf
were curtailed or ceased for a week or several months? There would be some disruption to
the US economy, but the economy would not collapse if oil flows from the Middle East were
disrupted for some time. It is arguable that a total loss of Gulf oil for up to three months,
would be, at worst, quite expensive. In the short term, it is likely that the US would adapt —as it did when the oil imports from Iraq and Kuwait were halted after Iraq’s invasion of that
Kuwait in 1990. The principle reaction of world markets would be an increase in the priceof oil.
This would not be a devastation for three reasons. First, the US is less dependent on
Persian Gulf oil than in the past; the US has a more diverse supply network of petroleum,
including increases in domestic production and increased imports from Canada and othercountries. Second, the US has a strategic oil reserve containing 727 million barrels of oil,which could carry the US through several months of shortages in supply. And third, andperhaps most important, overall demand for oil has decreased in the US. Petroleum
consumption peaked in 2005 at 40 percent of total US energy consumption and has

58 Council on Foreign Relations, National Security Consequences of Oil Dependency: Report of an Independent

Task Force (Washington, DC: Council on Foreign Relations, 2006) p. 29. https://cfrd8files.cfr.org/sites/default/files/report_pdf/0876093659.pdf.
59 See Glaser and Kelanic, eds., Crude Strategy; John Glazer, “Does the U.S. Military Actually Protect Middle
East Oil?” Cato Institute, 9 January 2017. https://www.cato.org/publications/commentary/does-us-militaryactually-protect-middle-east-oil; Emma Ashford, “Unbalanced: Rethinking America’s Commitment to theMiddle East,” Security Studies Quarterly, vol. 12, no. 1 (Spring 2018) pp. 127-148. Also see Milton R. Copulos,“America’s Achilles Heel: The Hidden Cost of Imported Oil,” The National Defense Council Foundation,(Washington, DC: October 2003).
http://citeseerx.ist.psu.edu/viewdoc/download;jsessionid=DD3F77E8166A096D9F1BB3B615199125?doi=1
0.1.1.186.7523&rep=rep1&type=pdf.
60 Joshua Rovner, “After America: The Flow of Persian Gulf Oil in the Absence of US Military Force,” in Glaserand Kelanic, eds., Crude Strategy, pp. 141-165: 160.

19

declined 10 percent since then. In 2017, petroleum accounted for 37 percent of US energy
consumption.61 China is more vulnerable than the US to Persian Gulf oil supply disruptions.
Nevertheless, economists tend to associate oil price shocks due to restrictions on theflow of oil (such as the Arab Oil Embargo) with recessions. This is true. Yet, because
military spending is less productive compared to other forms of spending — say on
education, health care, infrastructure, or renewable energy — military spending is arguably
an overall drag on the US economy because it produces fewer jobs than spending on othersectors. Which raises the question of whether, in protecting against a potential oil priceincrease, the US does more harm than it risks by not defending access to Persian Gulf oil. In
sum, the Persian Gulf mission may not be as necessary as the Pentagon assumes.
National Security Implications of Climate Change
The US military, the intelligence community, and scholars of international security havebeen warning of the dangers posed by climate change for several decades. The military andintelligence community tend to cluster the national security implications of global warming
induced climate change into two overlapping areas: how climate change will affect US
installations and military operations, including how responding to climate disasters will
stress military operations and potentially detract from other military missions; and how
climate change poses political and national security threats, up to and including war.62
The military has emphasized how climate change challenges military systems,
operations, and infrastructure. For instance, in May 1990, Terry P. Kelly produced a paper
for the Naval War College, “Global Climate Change Implications for the United States Navy”
emphasizing threats to Navy “naval operations, facilities, and systems” in coming decades.
The analysis focuses its recommendations on monitoring and adapting to climate change.63
More recently, the DOD offered a “Climate Change Adaptation Roadmap” in 2014 thatstressed the necessity of preparing for and adapting to climate change.64 In early 2018, theDOD reported that about half of their installations had already experienced climate change
related effects.65 A year later, the DOD reported that the US military is already experiencing
the effects of global warming at dozens of installations.66 These include recurrent flooding

61 US Energy Information Agency, https://www.eia.gov/energyexplained/?page=us_energy_home.
62 For instance, see the US National Intelligence Council, “Implications for U.S. National Security of AnticipatedClimate Change,” 21 September 2016.
63 Terry P. Kelly, “Global Climate Change Implications for the United States Navy” Naval War College, May
1990. https://documents.theblackvault.com/documents/weather/climatechange/globalclimatechangenavy.pdf.
64 Department of Defense, “2014 Climate Change Adaptation Roadmap,”
https://www.acq.osd.mil/eie/Downloads/CCARprint_wForward_e.pdf.
65 Office of the Undersecretary of Defense for Acquisition, Technology and Logistics, “Department of Defense,
Climate-Related Risk to DOD Infrastructure Initial Vulnerability Survey (SLVAS) Assessment Report,”(January 2018). https://climateandsecurity.files.wordpress.com/2018/01/tab-b-slvas-report-1-242018.pdf.
66 Department of Defense, “Report on the Effects of a Changing Climate to the Department of Defense,” Officeof the Undersecretary of Defense for Acquisition and Sustainment, January 2019.

20

(53 installations), drought (43 installations), wildfires (36 installations) and desertification(6 installations). Vulnerability will only increase over the next twenty years unless theworld begins to dramatically reduce all greenhouse gas emissions and sequester carbon
dioxide.67
The most urgent threat to infrastructure has perhaps been the Navy’s on-going concernthat rising sea levels and major storms will inundate coastal infrastructure and limit theuse of naval bases.68 For instance, melting permafrost in the Arctic threatens the physicalstability of the US military facilities there, Norfolk Naval Base is being inundated, andKeesler Air Force Base is regularly flooding. The National Climate Assessment released inlate 2018 showed images of the US Naval Base at Norfolk Virginia as particularly
vulnerable.
Figure 10. US Military Assets with Climate-Related Vulnerabilities.69

The Pentagon’s response to the infrastructural and operational challenges of climatechange has been to urge military preparations. These include potentially moving or closing
military bases, developing training and equipment to operate in hotter and wetter or drier
climates to meet climate change related threats to operations and resiliency.

https://climateandsecurity.files.wordpress.com/2019/01/sec_335_ndaareport_effects_of_a_changing_climate_to_dod.pdf.
67 Department of Defense, “Report on the Effects of a Changing Climate to the Department of Defense,” p. 5.
Thawing permafrost is already occurring at Fort Greeley, Alaska.
68 See U.S. Navy “Climate Change Roadmap,” April 2010, Department of the Navy,
https://www.navy.mil/navydata/documents/ccr.pdf.
69 Source: Figure 1.9. United States Global Change Research Program, Fourth National Climate Assessment:
Volume II Impacts, Risks and Adaptation in the United States, (2018) https://nca2018.globalchange.gov/.

21

In addition to the concern that a decline in access to oil would hurt the US and theglobal economy, the DOD has long been concerned that the US military itself, by requiring
enormous quantities of fuel for its operations, is too dependent on oil. Specifically, high fuelconsumption rates during war — for weapons, equipment, heating and cooling tents —increase the need to transport fuel to conflict zones, which is itself a vulnerability and a lossof efficiency. Further, fuel has to be protected in transit and is vulnerable to disruptions in
supply.
For example, during the US occupation of Afghanistan, US and NATO forces weredependent on the transit of fuel through Pakistan. Importing fuel into Afghanistan throughPakistan — where it comprised between 30 and 80 percent of each convoy — made thetankers vulnerable to attack. Between 2008 and 2014 convoys were attacked en route
through Pakistan to NATO bases in Afghanistan 485 times, causing 167 deaths and 450
injuries. As the then Secretary of the Navy, Ray Mabus said, “Fossil fuel is the No. 1 thing we
import to Afghanistan and getting that fuel is keeping the troops doing what they were sent
there to do, to fight or engage the local people.”70 Further, tanker convoys through Pakistan
were disrupted from late 2011 to early 2012 after the US inadvertently killed Pakistani
troops and Pakistan halted those convoys for several months.
In 2003, then Marine Corp General John Mattis said that the US had to be “unleashedfrom the tether of fuel.” In 2011, when asked by Congress member Adam Smith during
Armed Services Committee Hearings Mattis elaborated.
On the fuel, it is a significant Achilles heel for us when you have to haul the amounts offuel that we have to haul around the battlefield for the generators and for the vehicles.
We are working with DARPA [Defense Advanced Research Projects Agency], we areworking with a number of civilian organizations to try and find solutions. There are
efforts under way to make more expeditionary bases which would actually generatesome of their own energy requirements using, for example, solar power. In many ofthese places, there is a lot of sunshine. If we can get expeditionary capability to capturethat and then basically recharge our batteries. I mean, it is an amazingly complex effort
to maintain the fuel lines. And it also gives the enemy an ability to choose the time andplace of attacking us. We are engaged with Science and Technology, we are engaged
with DARPA, and we are looking at very pragmatic ways of doing this. We are also
looking at what we can do to actually change how we distribute fuel, to reduce theenemy's opportunities to come after us.71

70 Elisabeth Rosenthal, “U.S. Military Orders Less Dependence on Fossil Fuels,” The New York Times, 4 October

2010, https://www.nytimes.com/2010/10/05/science/earth/05fossil.html.
71 Mattis at the Committee on Armed Services, Hearing on National Defense Authorization Act for Fiscal Year2012, 3 March 2011. https://www.govinfo.gov/content/pkg/CHRG-112hhrg65114/html/CHRG112hhrg65114.htm.

22

Figure 11. Attacks on NATO Supply Convoys Through Pakistan, 2008 to 201472

160
140
120

Nimber

100
80
60
40
20
0
2008

2009

2010
Incidents

2011
Killed2012
Injured

2013

2014

The Pentagon’s response to concerns about fuel use has been to track fuel consumption,and to find ways to decrease consumption of fossil fuels through conservation andincreased investment in renewable energy. The military efforts to reduce dependency haveincluded reducing energy used at military installations and educating soldiers about theneed to minimize idling vehicles — from Humvees to tanks, to jets.
For example, in 2009 the newly created Marine Corps Expeditionary Energy Officebegan to collect data on Marine Corp energy usage from bulk distribution to the unit
level.73 The Marines have gone quickly from analysis to action. In 2009, the Marines madetheir first study of fuel use in Afghanistan and in the following year the Marine Corps sent
solar panels and chargers to their forces there.74 A few months later, the solar panels
deployed in the Ground Renewable Expeditionary Energy System (Greens) had reportedly
cut generator fuel consumption by nearly 90 percent, from 20 to 2.5 gallons per day.75 In2010 the DOD established a Senior Sustainability Council. All of this work on efficiency has
72 Source of data: Pak Institute for Peace Studies, annual Pakistan Security Report,

https://www.pakpips.com/publications#1512730923805-d52fde57-07fa.
73 See, Marine Corps, “United States Marine Corps Energy Expeditionary Strategy and Implementation Plan:
Bases to Battlefields,” 2010.
https://www.hqmc.marines.mil/Portals/160/Docs/USMC%20Expeditionary%20Energy%20Strategy%20%
20Implementation%20Planning%20Guidance.pdf.
74 Suzanne Goldenberg, “US Marines in Afghanistan Launch First Energy Efficiency Audit in War Zone,” The
Guardian, 13 August 2009, https://www.theguardian.com/environment/2009/aug/13/us-marinesafghanistan-fuel-efficiency.
75 Spencer Ackerman, “Afghanistan’s Green Marines Cut Fuel Use by 90 Percent,” Wired, 13 January 2011,https://www.wired.com/2011/01/afghanistans-green-marines-cut-fuel-use-by-90-percent/.

23

been accelerated and would not only save money, the military emphasizes, but also
increase the resilience of the armed forces.76
In addition, the Pentagon uses other fuels and has continued to diversify its energy
supplies. The US military relies on nuclear power for some important uses — most notably
to power its fleet of 11 aircraft carriers. It is possible to substitute some alternative fuels
for military applications and research on using bio-fuel in military vehicles, including jets.
The Pentagon has increased its use of renewable energy since 2009. The military has
made a massive investment in solar generation and other renewable energy, doubling
renewable power generation between 2011 and 2015.77 But so far, switching to renewablesources has yielded the savings in emissions offsets less of than 1percent of US DOD
Greenhouse Gas emissions.78 Taken together, these efforts have borne fruit; the military
has significantly reduced fuel use — even while waging war in Afghanistan, Iraq, and Syria— and there is enormous scope for reducing emissions even further. In 2017, the military’s
push to reduce energy consumption ran into politics when the Trump administration
decided to deny climate change. The Pentagon was put in an awkward position; a headline
in Fortune magazine framed the issue nicely “The Military is Getting Greener, but That
Clashes with Trump’s Promises.”79
The other operational concern is the threat climate change poses to the military’s
capacity to perform its core missions. National security officials anticipating a growing role
supporting civil authorities in disaster relief missions are concerned that natural disasters,
made worse as a consequence of climate change, will stress the operational capacities of
the US military. As sea levels rise, critical civilian infrastructure will be at risk. In
September 2016, President Obama issued a National Security Memorandum that said,“Climate change and associated impacts on U.S. military and other national security-related
missions and operations could adversely affect readiness, negatively affect militaryfacilities and training, increase demands for Federal support to non-federal civil
authorities, and increase response.”80

76 Office of the Assistant Secretary of Defense, Department of Defense Annual Energy Management andResilience Report (AEMRR) https://www.acq.osd.mil/eie/Downloads/IE/FY%202017%20AEMR.pdf.
77 Timothy Garder, “U.S. Military Marches on Toward Green Energy, Despite Trump,” Reuters, 1 March 2017,https://www.reuters.com/article/us-usa-military-green-energy-insight/u-s-military-marches-forward-ongreen-energy-despite-trump-idUSKBN1683BL. Also see Reuters, “military Getting Greener,”
http://fingfx.thomsonreuters.com/gfx/rngs/USA-TRUMP-ENERGY-MILITARY/0100400G00X/index.html.
78 Annual Data on Energy from https://www.energy.gov/eere/femp/federal-facility-annual-energy-reportsand-performance.
79 Associated Press, “The Military is Getting Greener, but That Clashes with Trump’s Promises.” Fortune, 14
January 2017. http://fortune.com/2017/01/14/military-oil-trump-green-power/.
80 Memorandum for the Heads of Executive Departments and Agencies, Climate Change and National Security,
21 September 2016, https://www.justice.gov/opa/file/895016/download.

24

Climate Chaos and War
The military has become increasingly concerned that climate change poses a threat tointernational security.81 In the 2015 National Security Strategy, the Obama Administration
said, “Climate change is an urgent and growing threat to our national security, contributing
to increased natural disasters, refugee flows, and conflicts over basic resources like foodand water. The present day effects of climate change are being felt from the Arctic to theMidwest. Increased sea levels and storm surges threaten coastal regions, infrastructure,and property. In turn, the global economy suffers, compounding the growing costs of
preparing and restoring infrastructure.”82
In the most recent National Security Strategy, the Trump administration ignored
climate change. In response, more than 100 members of Congress wrote to the President inJanuary 2018 to underscore the risks and to urge the President to include climate change in
the National Security Strategy.83 And at the same time, Retired Admiral James Stavridis
argued that climate change was arguably the most pressing national security challenge the
US faced. Stavridis said, “What makes climate change so pernicious is that while the effects
will only become catastrophic far down the road, the only opportunity to fix the problem
rests in the present. In other words, waiting ‘to be sure climate change is real’ condemns us
to a highly insecure future if we make the wrong bet. We are in danger of missing not only
the vast forest of looming climate change, but the ability to see some of the specific treesthat will cause us the most problems.”84
The military has been concerned that climate change will lead to a more chaotic anddangerous world. They are concerned for instance that the Arctic Sea is now open, leading
to questions about the need to patrol it.85 National security analysts now frequently suggestthat drought in Syria from 2007 to 2010, and the subsequent mass migration to cities,
created the conditions that contributed to the emergence of the civil war there in 2011.
Indeed, strategists paint nightmare scenarios where climate change leads to armed
conflict — such as when crop failures produce famine and drought lead to conflicts overwater and other natural resources. The White House said in 2016 that “The national
81 For instance, see Kurt M. Campbell, et al, “The Age of Consequences: The Foreign Policy and National

Security Implications of Global Climate Change,” Center for Strategic & International Studies and Center for
New American Security, November 2007. https://csis-prod.s3.amazonaws.com/s3fspublic/legacy_files/files/media/csis/pubs/071105_ageofconsequences.pdf. Center for Naval Analysis,
National Security and the Threat of Climate Change, Center for Naval Analysis 2007.
https://www.cna.org/cna_files/pdf/national%20security%20and%20the%20threat%20of%20climate%20c
hange.pdf.
82 White House, “National Security Strategy,” February 2015, p. 12.
https://obamawhitehouse.archives.gov/sites/default/files/docs/2015_national_security_strategy_2.pdf.
83 The letter is found at https://langevin.house.gov/sites/langevin.house.gov/files/documents/01-1118_Langevin_Stefanik_Letter_to_POTUS_Climate_Change_National_Security_Strategy.pdf.
84 James Stavridis, “America’s Most Pressing Threat? Climate Change” Bloomberg Opinion, 11 January 2018,https://www.bloomberg.com/opinion/articles/2018-01-11/america-s-no-1-enemy-climate-change.
85 US Navy Task Force on Climate Change, “The United States Navy Arctic Roadmap, 2014-2030,” February
2014, http://navysustainability.dodlive.mil/files/2014/02/USN-Arctic-Roadmap-2014.pdf.

25

security implications of climate change impacts are far-reaching, as they may exacerbate
existing stressors, contributing to poverty, environmental degradation, and politicalinstability, providing enabling environments for terrorist activity abroad. For example, theimpacts of climate change on key economic sectors, such as agriculture and water, can haveprofound effects on food security, posing threats to overall stability.”86 Similarly, in
September 2016, the National Intelligence Council listed a range of concerns fromincreased migration, to food shortages, to greater conflict and war caused by shortages offresh water and access to arable land.87 The intelligence community has kept its eyes on
climate change even as President Trump denies that global warming is a problem. In
January 2019, Daniel R. Coats, Director of National Intelligence told the Senate SelectCommittee on Intelligence that, “Global environmental and ecological degradation, as well
as climate change, are likely to fuel competition for resources, economic distress, and social
discontent through 2019 and beyond. Climate hazards such as extreme weather, higher
temperatures, droughts, floods, wildfires, storms, sea level rise, soil degradation, andacidifying oceans are intensifying, threatening infrastructure, health, and water and foodsecurity. Irreversible damage to ecosystems and habitats will undermine the economic
benefits they provide, worsened by air, soil, water, and marine pollution.”88Part of the Pentagon’s response to concerns about climate change has been to create
new organizations within the DOD and to study the issue.89 For instance, the Navy createdthe “Task Force Climate Change” (TFCC) in 2009. However, the Pentagon does not
acknowledge that its own fuel use is a part of the problem or that reductions in Pentagon
fuel use are a potentially significant way to reduce the risks of climate caused national
security risks. But the Pentagon could make the same connections that Henry Waxman
made more than two decades ago. In May 1998, Congressman Henry Waxman said, “theKyoto Protocol will improve the national security of the United States by reducing the riskof catastrophic climate change, which would create upheaval and unrest throughout theworld, including the potential for millions of environmental refugees.” Waxman also argued
that “measures to implement the Kyoto Protocol can improve our security by reducing ourdependence on imported oil through improved energy efficiency and increased reliance on
domestic renewable energy resources.”90

86 White House, “Findings from Select Federal Reports: The National Security Implications of Climate Change”

May 2015, p. 3.
87 National Intelligence Council, “Implications for US National Security of Anticipated Climate Change,” NIC
WP2016-01, 21 September 2016.
https://www.dni.gov/files/documents/Newsroom/Reports%20and%20Pubs/Implications_for_US_National_
Security_of_Anticipated_Climate_Change.pdf.
88 Daniel R. Coats, “Worldwide Threat Assessment of the US Intelligence Community, Statement for the
Record,” Senate Select Committee on Intelligence” 29 January 2019.
https://www.dni.gov/files/ODNI/documents/2019-ATA-SFR---SSCI.pdf, p. 23.
89 On the other hand, a 2017 GAO report suggested that the US military had not consistently taken the likely
budgetary impacts of climate change into account. Government Accountability Office, “Climate Change
Adaptation: DOD Needs to Better Incorporate Adaptation into its Planning and Collaboration at Overseas
Installations. November 2017. https://www.gao.gov/assets/690/688323.pdf.
90 Waxman, 20 May 1998. Congressional Record, House, vol. 144, part 7, Proceedings and Debates of the 105th
Congress, p. 9983.

26

Conclusion
Even as the US says it will scale back the size of its military presence in Afghanistan,Iraq, and Syria, the US has begun a massive build-up of its military capacities. The US
military budget is larger than it has ever been since the end of the Cold War. The US seems
to be on track to continue policing the Persian Gulf even as it turns to what it perceives isan emerging threat from China and has an increasing military presence in Africa. All ofthese activities demand fuel consumption and are hence greenhouse gas emission
intensive.
The US has an important public policy decision to make. Do we continue to orient ourforeign policy and military force posture toward ensuring access to fossil fuels? Or do wedramatically reduce the use of fossil fuels, including the military’s own dependency, andthus reduce the perceived need to preserve access to oil resources?
Reductions in military fuel use would be beneficial in four ways. First, if the US were to
decrease its dependence on oil, the US could reduce the political and fuel resources it uses
to defend access to oil. If the US further reduced its imports of oil from the Persian Gulf,
including fuel used by the military to protect those imports, it could then reevaluate thesize of the US military presence in the region and reevaluate its relationship with Saudi
Arabia and other allies in the region. The US would reap political and security benefits,
including reducing the dependence of troops in the field on oil and decreasing dependenceon oil and those who provide it.
Second, by dramatically decreasing fossil fuel consumption, the US military would
reduce overall US greenhouse gas emissions and perhaps promote carbon sequestration(taking carbon out of the atmosphere and fixing it in the soil and trees). There are many
ways to do this, from more modest measures such as increasing fuel economy and using
alternative fuels, which the Pentagon has begun to do. Some base closures will benecessitated by climate change itself. More significant reductions in greenhouse gas
emissions will be gained by restructuring the US military posture, including reducing US
military operations and installations worldwide, and closing bases in the US. Base closures
could also lead to significant carbon sequestration if those public lands are reforested. See
Appendix 2 for modest suggestions for Congressional action.
Third, by reducing the use of greenhouse gas-emitting fuels (coupled with emission
reductions in other sectors) the Pentagon would decrease its contribution to the associatedclimate change threats to national security. Indeed, the Pentagon could play a major role in
reducing the worst effects of climate change, and any potential security consequences ofglobal warming, rather than reacting or cleaning up after those effects have occurred.
Fourth, as a consequence of spending less money on fuel and operations to provide
secure access to petroleum, the US could, in the long run decrease US military spending andreorient its economy to more economically productive activities. Indeed, if the US militaryconverted more of its energy consumption to renewable energy, this would stimulate the27renewable energy industry in the US, with important economic benefits for the entire US
economy.91
In sum, reducing Pentagon fossil fuel use could have enormous positive implications forthe climate.

Appendix 1. Calculating US Military Greenhouse Gas Emissions
Due to gaps in reporting and accounting, it is impossible to provide a precise calculationof the total greenhouse gas emissions of the US military. Most US government accounting of
US greenhouse gas emissions omit figures on how much the military and military industry
contributes to US emissions. This is in part because the Pentagon does not releasepetroleum fuel consumption data. Further, as discussed below, emissions frominternational bunker fuels (for military aircraft and ships) and multilateral wars were
excluded from national accounts in the Kyoto Protocol negotiations in 1998. The US does
not appear to count most bunker fuels in its Greenhouse Gas Inventory national totals.92
Absent a full Pentagon accounting of their fuel consumption and emissions by operation
there are various ways to estimate DOD greenhouse gas emissions in the post-9/11 wars.
One could base an estimate of the proportion of total greenhouse gas emissions that should
be attributed to the war on the proportion of the total military budget spent on Overseas
Contingency Operations. In other words, one can use the average portion of the DOD
budget spent on Overseas Contingency Operations as an approximate measure of energy
use related to the war effort and assume that some portion of the base budget, andtherefore base/non-war operations and installation energy use is correlated to war related
spending. The Overseas Contingency Operations budget for the major war zones accounted
for an average of 17 percent of the entire DOD (top line) budget from 2001 to 2017. But
this rule of thumb would give an estimate of war related emissions that would be too low
since non-standard emissions account for such a high proportion of all DOD fuel use.
A better way to estimate greenhouse gas emissions due to war would be to focus on
non-standard fuel consumption and to estimate total greenhouse gas emissions forOverseas Contingency Operations. For example, on average, between 2010-2017 the91 The author thanks Alexander Thompson for raising this point.
92 See US Environmental Protection Agency, Inventory of Greenhouse Gases and Sinks: 1990-2016,

https://www.epa.gov/sites/production/files/2018-01/documents/2018_complete_report.pdf and US
Environmental Protection Agency, Inventory of Greenhouse Gases and Sinks: 1990-2017,https://www.epa.gov/sites/production/files/2019-02/documents/us-ghg-inventory-2019-main-text.pdf.
Also see Annex 3, Part A, Section 3.8 where the method is to “omit all international fueltransactions/deliveries” and “all land based fuels.” https://www.epa.gov/sites/production/files/201902/documents/us-ghg-inventory-2019-annex-3-additional-source-or-sink-categories-part-a.pdf.

28

Department of Energy attributed 65.9 percent of all DOD greenhouse gas emissions to nonstandard operations. But to assume that all non-standard fuel use was for the major wars
would yield an estimate that would be too high since the DOD performs other, non-post9/11 war missions.
Another and arguably even better method would be to base the estimate of greenhousegas emissions on the major wars on the proportion of fuel use by Central Command. In
FY2014 (see figure 4) this was about 24 percent of the total non-standard operational fuelconsumption by the DOD. But because the US counterterror operations are underway allover the world (in about 80-90 countries) the Central Command is not the only war zone in
the global war on terror. The estimate here is that the portion of all greenhouse gas
emissions related to the Global War on Terror, in patrolling the Persian Gulf, and Central
Command Overseas Contingency Operations is about 35 percent of total greenhouse gas
emissions for non-standard and standard operations.
The estimates of greenhouse gas emissions by the DOD in this analysis are based
calculations of US government data on fuel consumption from the US Department ofEnergy, Comprehensive Annual Energy Data and Sustainability Annual Reports.93 Data forstandard and non-standard greenhouse gas emissions by Department is available on the
Department of Energy website for FY2008, and FY2010-2017. In addition, the Departmentof Energy provides non-standard fuel consumption data for vehicle and equipment energy
use for other years.94
It is possible to calculate annual DOD vehicle and equipment caused greenhouse gas
emissions for each fuel type based on fuel consumption rates. For example, a calculation of
CO2 equivalent emissions of jet fuel makes the following assumptions: each gallon of jet
fuel produces 0.135 HHV MMBtu/gallon. Using the standard emission factors for jet fuel —CO2 of 72.22 kg/ MMBtu; for CH4 (methane) of .003 kg/MMBtu; and for N2O (nitrous
oxide) of .0006 kg/MMBtu — one can calculate the greenhouse gas, CO2 equivalent,emissions for a given quantity of jet fuel.95 The Global Warming Potential 100 year values
are the EPA and Department of Energy assumptions of 25 for methane and 298 for Nitrous
Oxide.96
Department of Energy provided consumption data, and the EPA Global Warming
Potentials for CO2, CH4 and N2O were used to calculate greenhouse gas emissions for
93 Department of Energy, “Comprehensive Annual Energy Data and Sustainability Performance,” Annual

Reports,
http://ctsedwweb.ee.doe.gov/Annual/Report/ComprehensiveGreenhouseGasGHGInventoriesByAgencyAndF
iscalYear.aspx. Data as of 1 June 2018.
94 Energy consumption from the Department of Energy,
http://ctsedwweb.ee.doe.gov/Annual/Report/HistoricalFederalEnergyConsumptionDataByAgencyAndEnerg
yTypeFY1975ToPresent.aspx.
95 CO2, Methane and Nitrous Oxide emission factors are from Office of Energy & Renewable Energy, Federal
Comprehensive Annual Energy and reporting Requirements, https://www.energy.gov/eere/femp/federalfacility-consolidated-annual-reporting-requirements.
96 GWP emissions coefficients, https://www.eia.gov/environment/emissions/co2_vol_mass.php.

29

gasoline, diesel, LPG/propane, aviation gas, jet fuel, and Navy special fuel for the years
where there is no published Department of Energy emissions data.97 For example,
calculations of CO2e emissions for US DOD jet fuel consumption in 2017 are illustrated inTable 3.
Table 3. Calculating Greenhouse Gas Emissions for US Military Jet Fuel Consumption,
FY2017

Annual Consumption GHG NonStandard Operations
Total Energy Consumed
Cost
Unit Cost
Anthropogenic CO2 Emission Factor

Jet Fuel

Unit of Measure

2,915,738.50
393,624,693.30$6,681,061.20
$2.29
72.2

thousand gallons
MMBTU

kg CO2/MMBtu

CH4 Emission Factor
N2O Emission Factor
Total Quantity Emitted Anthropogenic
CO2
Total Quantity Emitted CH4

0.003
0.0006kg CH4/MMBtu
kg N2O/MMBtu

28,427,575,352.60
1,180,874.10

kg
kg

Total Quantity Emitted N2O
GWP Factor for CO2
GWP Factor for CH4
GWP Factor for N2O
Total Quantity Emitted (CO2e)
Total Quantity Emitted (MT CO2e)

236,174.80
125
298
28,527,477,299.80
28,527,477.30

kg
CO2e
CO2e
CO2e
kg CO2e
MT CO2eAssuming that non-standard emissions from vehicle fuel consumption were very close
to the total non-standard fuel consumption for the DOD, standard emissions were
estimated for each year. During the years where there is Department of Energy data for
DOD emissions, non-standard emissions were on average 63 percent of total emissions.
Total and standard emissions were estimated assuming that the ratios were the same
through the entire period. The results are graphed in the following figure and shown in
Table 4.

97 The Department of Energy has published emissions data for non-standard emissions for 2008, and 2010-2017. They have provided vehicle fuel consumption data for the years 1975-2017. Annual GHG CO2eemissions from fuel consumption data are calculated assuming that vehicle consumption was the majority of
non-standard consumption.

30

Figure 12. Estimated DOD Greenhouse Gas Emissions, 1975-201798
120

Millions of Metric Tons CO2e

100

80

60

40

-

1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017

20

Standard Emissions

Non-Standard Emissions

Total CO2e Emissions

Table 4. Estimated Annual Greenhouse Gas Emissions of the DOD, 1975-201799

1975
1976
1977
1978
1979
1980
1981
1982
1983

Standard
Emissions
Millions ofMetric Tons
40
35
35
34
35
36
39
39
39

Non-Standard Emissions
Millions of Metric Tons
69
59
60
58
60
61
66
67
67

Total CO2e Emissions
Millions of Metric
Tons
109
93
95
92
95
97
104
107
106

98 For FY2008 and FY2010-2017, this estimate uses the Department of Energy figures. The other years are

estimates calculated from Department of Energy fuel consumption data.
99 Calculated from Department of Energy fuel consumption data. For FY2008 and FY2010-2017, using the
Department of Energy reported figures.

31

1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000

40
39
39
40
35
40
39
41
32
32
30
28
27
27
25
25
23

68
67
66
69
60
68
66
69
55
55
51
48
46
45
43
42
39

109
106
105
109
95
109
105
110
88
87
80
76
74
72
69
66
62

2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015

23
26
29
32
31
27
28
27
28
27
26
25
24
24
24

40
44
49
54
52
46
48
50
48
50
49
45
39
38
39

63
70
78
85
83
73
76
77
77
77
75
70
64
62
63

2016
2017
Total

22
22
1,340

37
37
2,290

59
59
3,629

32

These estimates are likely conservative for three reasons.
First, the impact of methane and nitrous oxide gases, their Global Warming Potentials(GWP) is not the same as C02 but significantly higher. When calculating the total
greenhouse gas emissions these other greenhouse gases are scaled into an equivalentrelation to carbon dioxide, which has, by definition, a GWP of 1. The Department of Energy
and the EPA use the US EPA 100 year Global Warming Potentials which scales the GWP ofmethane, CH4, at 25 and nitrous oxide, N2O, at 298 over 100 years.100 The
Intergovernmental Panel on Climate Change Fifth Assessment Report uses different GWP of
34 for Methane’s CO2 equivalent.101 If the IPCC global warming potentials were used,
estimates of US DOD greenhouse gas emissions would be higher.
Second, recall that jet fuel is the major source of vehicle non-standard military
greenhouse gas emissions. CO2 is the major product of jet fuel consumption but jet fuelcombustion emissions at high altitude also contain the much more potent greenhouserelease water vapor, a global warming gas, which itself causes the formation of cirrus
clouds. The DOD puts additives in its jet fuels to ensure they perform according to militaryrequirements. For instance, because military jets fly at much higher altitudes thancommercial jets they use additives to ensure that the fuel lines do not freeze. Any emissions
from those additives and water vapor are not counted. Scientists agree that even though
CO2 is the major product of jet fuel consumption, the impact of these other greenhousegases is significant. While the Department of Energy figures and the calculations here
include nitrous oxide and methane, it is possible that the additional effects of high altitude
water vapor and additives for jet fuel combustion, which are not included in thesecalculations, may be significant. “Non-CO2 impacts cannot be ignored as they potentiallyrepresent approximately 60% of total climate impacts that are important in the shorter
term (excluding cloudiness impacts).”102 In sum, this means that the impact of aviation

100 PFCs, HFCs, NF3, and SF6 have global warming potentials that range from 7,390 to 22,800. While theglobal warming effects of methane, nitrous oxide and water vapor are well understood, when they are
emitted during jet fuel combustion at high altitudes the effects are not as well understood as the effects of
CO2. See the US Environmental Protection Agency, “Emissions of Flourinated Gases,”
https://www.epa.gov/ghgemissions/overview-greenhouse-gases#f-gases and “Understanding Global
Warming Potentials,” https://www.epa.gov/ghgemissions/understanding-global-warming-potentials. The
Department of Energy uses the EPA GWP factors. See their Energy Management Data Report.
https://www.energy.gov/eere/femp/downloads/annual-energy-management-data-report and Council on
Environmental Quality, “Federal Greenhouse Gas Accounting and Reporting Guidance,” 17 January 2016, p. 4.
https://www.sustainability.gov/pdfs/federal_ghg%20accounting_reporting-guidance.pdf.
101 IPCC Second Assessment Report 100 GWP See the IPCC Fifth Assessment Report, Climate Change 2014:
Synthesis Report. Contribution of Working Groups I, II and III to the Fifth Assessment Report of theIntergovernmental Panel on Climate Change [Core Writing Team, R.K. Pachauri and L.A. Meyer (eds.)]. (IPCC,
Geneva, Switzerland, 2014).
https://www.ipcc.ch/site/assets/uploads/2018/02/SYR_AR5_FINAL_full.pdf.
102 European Environment Agency, European Union Aviation Safety Agency, Eurocontrol, “European Aviation
Environment Report, 2019” January 2019, p. 88.
https://www.easa.europa.eu/eaer/system/files/usr_uploaded/219473_EASA_EAER_2019_WEB_LOWRES.pdf. Also see Martin Cames, Jakob Graichen, Anne Siemons, and Vanessa Cook, “Emission Reduction
Targets for International Aviation and Shipping,” Policy Department A: Economic and Scientific Policy,

33

emissions when all greenhouse gases are included may be higher than those estimatedhere.
Third, the focus is on the major emissions of the DOD. Specifically not included are
estimates for what are called Scope 3 emissions from, for instance, employee air andground business travel, wastewater treatment, and solid waste disposal. For example, US
DOD Scope 3 emissions in 2008 were 7.6 million MT CO2e and in 2016, 7 million MT CO2e.
Nor are biogenic emissions included. In 2017, US DOD biogenic emissions were .57 million
MT CO2e.
Finally, international military bunker fuels are excluded from greenhouse gas emission
accounting. As part of the Kyoto Protocol, signed in December 1997, the US insisted that
fuel sold to ships and aircraft for international transport and for multilateral military
operations, “bunker fuels” should not be counted against a country’s total emissions.103 As
the US Undersecretary of State Stuart Eizenstat said in testimony to Congress, the Kyoto
Protocol did not limit the US:
We took special pains, working with the Defense Department and with our uniformed
military, both before and in Kyoto, to fully protect the unique position of the UnitedStates as the world's only super power with global military responsibilities. We
achieved everything they outlined as necessary to protect military operations and ournational security.
At Kyoto, the parties . . . took a decision to exempt key overseas military activities fromany emissions targets, including exemptions for bunker fuels used in international
aviation and maritime transport and from emissions resulting from multilateral
operations, such as self defense, peacekeeping, and humanitarian relief.
This exempts from our national targets not only multilateral operations expressly
authorized by the U.N. Security Council, such as Desert Storm or Bosnia, but,importantly, also exempts multilateral operations that the U.S. initiates pursuant to
the U.N. Charter without express authorization, such as Grenada.104
The Intergovernmental Panel on Climate Change continues to treat national militaryemissions, specifically international aircraft and naval bunker fuels, differently than otheremission types.105

European Union, November 2015, pp. 13-14.
http://www.europarl.europa.eu/RegData/etudes/STUD/2015/569964/IPOL_STU(2015)569964_EN.pdf.
103 See Roy K. Salomon, “Global Climate Change and U.S. Military Readiness,” Federal Facilities Environmental
Journal, Summer 1999, vol. 10, no. 2, pp. 133-142.
104 Undersecretary of State Stuart Eizenstat, testimony, Hearing Before The Committee on Foreign Relations,
11 February 1998, https://www.govinfo.gov/content/pkg/CHRG-105shrg46812/html/CHRG105shrg46812.htm.
105 See IPCC, “Good Practice Guidance and Uncertainty Management in National Greenhouse Gas Inventories,”
https://www.ipcc-nggip.iges.or.jp/public/gp/bgp/2_5_Aircraft.pdf.

34

Appendix 2. Possible Next Steps for Congressional Action on the DOD and Climate
ChangeThe Pentagon has made significant reductions in greenhouse gas emissions in recent
years. By continuing to decrease fossil fuel consumption, the US military would reduceoverall US greenhouse gas emissions and could perhaps promote carbon sequestration(taking carbon out of the atmosphere and fixing it in the soil and trees).
There is room for the DOD to continue reductions, using many more modest measures
including increasing fuel economy and using alternative fuels. More significant reductions
in greenhouse gas emissions will be gained by restructuring, including making training
more efficient, reducing US military operations and installations worldwide, and closing
bases in the US. Some base closures and restructuring will be necessitated by climatechange itself. Base closures could also lead to significant carbon sequestration if thosepublic lands are reforested.
This is a win-win-win strategy. Reductions in fuel use save money and make the US
military less vulnerable to fuel shortages; in the long run, reductions in fuel use andconversion of bases by reforestation decrease climate change caused impacts including
insecurity; and conversion to renewable energy sources and alternative fuels could
significantly boost the renewable energy industry and electric car industry in the US.
Congress might become much more active in tracking and reducing greenhouse gas
emissions by the DOD. Specifically, Congress might require the Pentagon to supply more
information on fuel consumption and energy use and require the Pentagon to increase its
analysis and planning for a transition to reductions in fossil fuel use and to immediately
reduce fuel consumption. Some potential actions are outlined below.
1. Comprehensive reporting of DOD fuel consumption and energy usage.
a. In all future years, the DOD should report fuel consumption to Congress in its
budgetary submission and in a separate annual report on DOD fuel consumption.
Consumption reports should be both aggregated and disaggregated (by fuel type e.g.
jet, diesel, and other fuels) each year by named operation and war, and for otheroperations and installations, for each operational command and eachservice. Consumption information should also be added to the annual Defense
Logistics Agency Energy Fact books.
b. The DOD should report these same figures for the period from FY2000 throughFY2019 in a separate report.
c. The DOD should report fuel consumption for training missions and public displays
such as fly-over events.
2. Comprehensive Analysis and Planning
a. DARPA should work with the services to produce a study showing current DOD
non-tactical vehicle fleet fuel consumption, and to identify ways to immediately
reduce fuel consumption beyond levels already targeted.
b. Each service should identify ways to reduce consumption of fuel by decreasing thefuel use and increasing the fuel efficiency of training exercises.
35

c. Each installation should inventory its environment to identify “heat islands” by theend of FY2020.
d. Each installation should produce plans to reduce overall energy consumption by 10
percent and 20 percent by the start of FY2022.
e. Identify installations that should be closed or reduced in size due to climate change
impacts (such as rising sea levels or extreme weather). Develop a plan forconverting these installations to sites for carbon sequestration.
3. Comprehensive Approach to Reductions in Fossil fuel usage.
a. Switching to alternative fuels for electricity generation at all US military installations
so that all DOD installations are 90 percent reliant on renewable technologies, e.g.
wind, solar, geothermal and hydropower and large storage capacity batteries
through power purchase agreements or local generation by 2022.
b. Increase the rate of adoption of all electric, hybrid and plug in hybrid non-tacticalfleet vehicles (NTV) based on the results of the DARPA study identified above. Moveto 90 percent electric, or gas-electric hybrid by 2022. Prioritize for new purchases
the most efficient vehicles made in the US that meet the Department of Energy NTV
fuel economy standards.
c. To reduce the “heat island” effect of large expanses of concrete and asphalt, andthereby reduce the necessity for air conditioning on bases and other installations,each base shall inventory its percentage of tree cover and plant shade trees so thatthe percentage of shade tree coverage is increased by 10-20 percent by the end of
FY2021.
4. Military and Installation Base Conversions and Closures
a. Designate which military and national guard bases and installations should beclosed due to climate change impacts and which bases can be closed for otherreasons, such as diminished threat.106b. As bases and installations are cleared of toxic contamination (such as chemical
waste and asbestos), change land use so that carbon sequestration is possible suchas by planting trees or restoring wetlands.
c. Use closed DOD bases and installations as sites of alternative energy production —wind, solar, or geothermal as is most appropriate and efficient for that base or
installation. Similarly, converted National Guard bases could become sites ofalternative energy production and carbon sequestration.

106 Department of Defense, “Report on the Effects of a Changing Climate to the Department of Defense,” Officeof the Undersecretary of Defense for Acquisition and Sustainment, January 2019.
https://climateandsecurity.files.wordpress.com/2019/01/sec_335_ndaareport_effects_of_a_changing_climate_to_dod.pdf.

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