The U.S. military is the largest institutional user of fossil fuels and polluter of carbon emissions in the world (Zarook). Additionally, the military acts as a massive subsidy to the oil industry through violently maintaining access to foreign oil for private extraction and use, which emits yet more carbon. Through this cycle of fossil fuel extraction, they are arguably the largest organizational contributor of carbon emissions causing climate change. This resulting atmospheric warming is causing planet-wide environmental havoc, including more frequent and intense natural disasters, extreme weather, habitat loss, and species extinction. This wide-ranging wreckage is current, compounding, hurting the country the military was founded to protect, and its allies, damaging ecosystems spanning land, air, water and all inhabitants in irreversible ways.
Reducing the U.S. military’s impact on the planet’s climate remains an underdiscussed decarbonization strategy. Carbon emissions directly from the military primarily originate domestically, but policy changes to reduce emissions would affect everywhere the U.S. military has bases or operates, plus supply chain manufacturing happening globally, and countries to which U.S. sells or donates its weaponry. The avoided climate consequences and positive market impacts of this decarbonization project would be felt globally.
Due to the structure of the federal government and military, as described in the U.S. Constitution and evolution since, decisions around the military’s direction stem from a complex web of parties with wildly varying incentives and goals.
- President of the U.S., as Commander in Chief. President Biden wants to be a leader on the environment but is pro-military freedom/expansion, has helped enact policy to prevent counting military emissions, and is wary of optics of being perceived as anti-military. Each President brings a new attitude to the issue, and can reverse course on their predecessor’s actions.
- U.S. Congress. Members of Congress, across parties, are generally pro-military-expansion, since it creates jobs and grows the economy. Republicans are forwardly enthusiastic, but to any extent others are less so, they are wary of same optics as the president, and the negative economic trade-offs for their constituents. Congress is not answerable to climate needs unless there’s re-election risk associated.
- Joint Chiefs of Staff and leadership of military branches. This group is unabashedly pro-military in growing the budgets and power over time. Yet their position is deeply intertwined with contributing to, mitigating, researching, and planning for climate collapse. They see climate as the most significant threat to military operations, and ostensibly want to mitigate that risk, but not in any way that would compromise military readiness or budgets. They will take pro-climate actions like installing renewable energy when it improves military readiness, but only under that justification. Under all types of leadership, the military has funded foundational research in climate, renewable energy/solutions, and been the first government branch to make major movements under the reasoning of climate change. This stakeholder does not fit cleanly under a “for” or “against” category.
- Military contractors. They want as much business and profit as possible with as little oversight/compliance on them as possible; they are anti-regulation on themselves but will seize opportunity to be profitably hired to handle the military’s regulatory compliance.
- U.S. taxpayers. They fund the military through taxes, and are aware of that role, but no majority expresses opinions on this issue.
The key takeaway from this list of stakeholders is that none of the major players weighs climate goals over military expansion.
For the majority of the military’s history, there was no concern, measurement, record-keeping, oversight, or legislation of its environmental impact of any kind. The destruction of enemies was, and widely still is, seen as worth any price tag, financial, human, or environmental. Until a few decades ago, this attitude coincided with the sense of the bountiful infinity of the earth, and the costs of war were seen through the former two lenses. At times, the U.S. military has exhibited pride in destroying the local environments of enemies, such as by spraying toxic chemicals including Agent Orange during the Vietnam War to cause widespread forest defoliation and kill crops. Massive-scale environmental destruction is the critical backdrop for any contemporary analysis of the military machine’s carbon footprint and other effects discussed in this paper.
As Bill Anderson, the former assistant secretary for installations, environment and logistics of the Air Force under President George W. Bush, said, “We’re concerned about climate change…but the first mission is bombs on target” (Von Kaenel). This attitude sums up the military’s contemporary attitude toward environmental issues. While we’ve seen accounting, mitigation, research, and other efforts in the climate space from the military, climate and environmental impacts remain at best secondary.
To evaluate the military’s environmental impact, a natural place to start is to use a system other large corporations and institutions engage with. The Task Force on Climate-Related Financial Disclosures (TCFD, created by the Financial Stability Board, a multilateral financial institution), provides the framework closest to a global standard for carbon footprint reporting, which is in use across Europe and the U.K. for various types of corporations and institutions, is currently in use by private companies for voluntary emissions reporting, and has been proposed by the S.E.C. for measuring and evaluating carbon emissions of public U.S. corporations starting as soon as next year. TCFD lays out the measurement of a carbon footprint as a key basis on which to evaluate climate impact, risk, and opportunity (“TCFD Recommendations”). Given this framework’s wide use and role in shaping how environmental footprints are evaluated, including in proposed U.S. federal policy, it provides a reasonable lens for evaluating the environmental impact of an institution, in this case the U.S. military. This analysis begins with measuring an inventory of carbon emissions, a step the the military has had a complex relationship with over the last thirty years.
- In 1992, the Rio Earth Summit made an early mention of warfare’s environmental impact. The Rio Declaration stated: “Warfare is inherently destructive of sustainable development” (“Report of the United Nations…”). While it agreed that each party should provide “a national inventory of anthropogenic emissions by sources and removals,” it left the carbon accounting methodology “to be promoted and agreed upon” at a later date, and did not require specific gases to be named, the sources listed, or impose limitations on the emissions themselves (“United Nations Framework Convention on Climate Change”).
- Since 1994, the United Nations Framework Convention on Climate Change (UNFCCC) has required ratifying countries, including the United States, to submit national inventories of greenhouse gas emissions.
- The EPA prepares this for the United States, following IPCC conventions. Though the Kyoto Protocol does not apply, the EPA uses its language for military methodology, including that “emissions emissions based upon fuel sold to ships or aircraft engaged in international transport should not be included in national totals, but reported separately,” and emissions resulting from international operations resulting from decisions made by the Charter of the United Nations “shall not be included in national totals, but reported separately; other emissions related to operations shall be included in the national emissions totals of one or more Parties involved.” This means military emissions that happen on another U.N. country’s territory are not included in United States national totals. From 1990–2000, the U.S. Navy classified 79-87% of fuel use as bunker fuels, to be excluded from reporting (Crawford 122).
- IPCC guidelines also state: “Due to confidentiality issues, many inventory compilers may have difficulty obtaining data for the quantity of military fuel use” (Crawford 121). They suggest aggregating military fuel use within another category to support this confidentiality (“Revised 1996 IPCC Guidelines”). For research, this means U.N. reports do not illuminate U.S. military emissions.
- 1997 Kyoto Protocol. When the language of the Kyoto Protocol was negotiated, the U.S. successfully pushed to exempt most military emissions from reporting requirements, and watered down other language (Crawford 104). The U.S. has since withdrawn; the agreement no longer affects our operations.
- The military’s representative at our convention pushed for the military exemptions, which was supported by Congress, including Senators Joe Biden and John Kerry, arguing it would impose fuel cuts which would reduce U.S. combat effectiveness, and “sacrifice…our ability to offer humanitarian assistance.” These included “bunker fuel” (fuel for multilateral military operations, in ships or aircraft) being excluded from emissions inventories, and emissions from overseas bases—an installation the U.S. has more than an order of magnitude of more than the next-highest country—count for the inventories of the host nation, unless negotiated otherwise by the countries.
- The U.S. simultaneously pushed for “flexible market mechanisms,” instead of mandatory measures or caps on emissions, to prevent carbon taxes or “heavy central regulation” from being imposed on U.S. industry.
- In 1998, the National Defense Authorization Act included the language: “Notwithstanding any other provision of law, no provision of the Kyoto Protocol to the United Nations Framework Convention on Climate Change, or any regulation issued pursuant to such protocol, shall restrict the training or operations of the United States Armed Forces or limit the military equipment procured by the United States Armed Forces.” This sums up the approach the United States has taken to the military carbon emissions.
- In 2001, President Bush withdrew the United States signature from the Kyoto Protocol.
- While the 2015 Paris Agreement committed parties to emissions reductions, including military emissions, both full disclosure and military emissions cuts are optional.
- President Biden set a net zero goal, with major exemptions, for the federal government. In December 2021, the Biden administration ordered federal agencies to submit plans for emissions reductions, including the Department of Defense, as part of the net zero by 2050 goal. However, it came with an exception: “The head of an agency may exempt from the provisions of this order any vehicle, vessel, aircraft, or non-road equipment that is used in combat support, combat service support, military tactical or relief operations, or training for such operations” (Biden).
- The U.S. Department of Energy and the DOD have begun to report U.S. military emissions since 2010, but the reports exclude scope 3, military contractors, and other major categories; with these key exclusions, the numbers are not in the order of magnitude of the true total.
- The totals, across scopes 1 & 2, decline from 76.5 MMTCO2e in 2010 to 54.8 MMT in 2019 (Crawford 128). (For many corporations, scope 3 emissions can be north of 90% of the total footprint.)
- Researchers have used military employment numbers, military budgeting, fuel purchase records, the numbers available from the DOD itself, and other proxies. Researcher Neta Crawford suggests these emissions closely track war; in 1975, she estimates that number to be 109 MMT, and in the 2000s, around 69 MMT annually (Crawford 152). Ho-Chih Lin and Deborah Burton have estimated global military emissions in 2017 around 445 MMT, around 1-5% of world emissions (Lin and Burton).
- None of these estimates include full scope 3 (the DOD briefly reported these numbers in the 2000s, but omitted dozens of categories), military contractors—which include construction, the design and fabrication of most weapons and equipment, essential operations around food, fueling, waste management, security, and more—biogenic emissions, destruction of property including oilfields (estimated to be 2% of worldwide CO2 emissions at peaks of the Gulf War), the additional greenhouse effect potential of contrails from high-altitude Air Force aircraft, and more. Environmental destruction like the estimated 11 million barrels of oil spilled into the Persian Gulf during the Gulf War are not counted by any emissions estimates (Crawford 172).
- In January 2021, Senator Ed Markey and Representative Mondaire Jones sent a public letter to President Biden asking for an end to the exemption of the DOD from the federal net zero goal (Markey).
- In November 2021, Representative Barbara Lee introduced H.Res.767, requiring the DOD to publicize its full emissions inventory, reduce emissions, among other environmentally-beneficial changes (Lee).
- Require the Department of Defense to do comprehensive carbon accounting on an annual basis of all operations, including military contractors, and release that information to the public. Researchers are estimating the carbon impact of the military with little concrete data on operations and next to none on contractors or supply chain. When preparing national emissions inventories, the EPA could forego the Kyoto Protocol language we had watered down and write more ambitious, transparent policy, referring to standard frameworks such as TCFD and the GHG Protocol along the way. We should set the example for the world. While the carbon accounting itself is complex, this is one of the most straightforward steps, allowing the world to understand the magnitude of the problem.
- Following Senator Markey’s request to President Biden, remove the exemption of national security organizations from participating in the federal net zero goal. Policy-wise, this is similarly straightforward, though the implementation will require innovation in every level of process, procurement, and operations inside the military and contractors.
- Re-assess the cost of fuel inside the military to include, including recursively along the fuel’s supply chain: predicted future damage to military operations/equipment and additional conflicts caused by climate change exacerbated by the fuel’s usage, and/or high-quality, durable carbon removal required to offset the fuel’s carbon footprint. These would incentivize lowering fuel usage. I lack the military accounting context to evaluate the feasibility of this project.
- “The Army says it will reduce emissions 50 percent by 2030 from its emission levels in 2005” (Crawford 250), but many of these emissions reductions, as they have in the past, will come from closing bases and reducing operations in Afghanistan and Iraq. While those emissions reductions count toward reducing climate change, these targets should be expanded to operations not closing down, on metrics based on remaining activity, such as per-base or per-troop emissions. This is the concept of additionality—the the extent to which the reductions are additional compared to a business-as-usual scenario—and if the bases would be closed for military strategy reasons unrelated to carbon impact, these reductions would be reverted by future deployments, without affecting base operations.
- Accelerate plans for renewable energy installations at bases. These have been cost-effective and less vulnerable to attack than armored fossil fuel delivery, yet few bases have installed these systems. Since many bases have successfully procured or directly installed clean electricity, and military leaders have proudly announced these projects to the public, accelerating these plans is one of the most politically viable steps to reducing military emissions.
- Shift DARPA funding dramatically toward sustainability-oriented projects, including energy storage and carbon removal. This step goes beyond the research and goals described in this paper, but depending on the scale, could have global impact on the available decarbonization solutions and their price.
- Accelerate sustainable aviation fuel goal timetables for the Air Force; in fiscal year 2016, 8.8% of of the Air Force fleet was powered by biofuels, which has been steadily increasing this century (Crawford 243). The Biden administration has plans (with an unclear path to the target) for all U.S. aviation fuel to be based on “sustainable aviation fuel” (SAF) by 2050, which includes biofuels (based on present biomass, versus fossil fuels from the past) and electrofuels (drop-in fuel replacements made from captured carbon, green hydrogen, and/or air/water). This would require technological breakthroughs and dramatic reductions in cost to achieve.
- Expand the net zero goal of the Army (limited to installations, which are 30% of energy consumption, and due by 2045) to the other branches. While decarbonizing submarines and high-power aircraft is not currently possible, it would drive research and innovation.
- The current ideology of the U.S. diplomacy and military strategy has revolved for decades around the idea that the U.S. must “protect the global flow of oil” (Crawford 90), which has led us into countless wars since World War II, with roots starting 170 years ago with coal-powered steamships. Considering military emissions closely track our engagement in wars, this ideology is at the root of perhaps several percent of total global emissions since World War II (Crawford 4). While this is an active position, it has been engrained over decades as a base assumption, so its reconsideration would result in political upheaval.
- As Crawford writes, “there is an opportunity to go from insecurity about the access, price, or supply of energy to less insecurity by decreasing dependence on fossil fuel” (Crawford 99). As the United States reduces its usage of oil—whether civilian or military—the military will have to protect access to less of it. The military seizing an opportunity to downsize would, unfortunately, be counter to all recent history; we have not cut budgets or programs even as we decreased direct warfighting. This is not likely.
- Additionally, around 40% of international shipping is to carry fossil fuels themselves ("Review of Maritime Transport"), meaning decreases in oil usage can enable a self-perpetuate a positive cycle of emissions reductions. If we do pursue this path, this cycle is encouraging in reducing oil use.
- Phase out military presence in the Middle East in the name of protecting access to oil. The United States keeps troops, aircraft carriers, bases, and other equipments permanently stationed strategically through the Middle East, ready for activation if any threat to American oil exploitation were to come up. Many strategists both inside and outside the military think this strategy is outdated, costly, and overly carbon-intensive, and could be phased out. The military proudly maintains the ability to send troops and equipment anywhere on earth on short notice if an issue were to come up. Affecting soldiers, their families, long-standing military alliances and global expectations, this would be a major event in U.S. history and not one a president is likely to undertake lightly.
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