The West’s armies are getting more serious about climate change

WESTERN DEFENCE ministries are talking up their willingness to take on a new enemy: climate change. In March Lloyd Austin, America’s defence secretary, wrote that “the changing climate is altering the global security and operating environments, impacting our missions, plans and installations.” The Pentagon set up a “Climate Working Group” after an executive order from President Joe Biden that climate considerations should be considered a greater foreign-policy and national-security priority.

American allies are making similar noises. On March 30th Britain’s Ministry of Defence (MoD) published its “Climate Change and Sustainability Strategic Approach”. In the foreword, Lieutenant-General Richard Nugee, who led the review, wrote: “The character of warfare is changing fast; so is the climate...The imperative could not be clearer: Defence must and will act now.” A few days previously, a meeting of NATO foreign ministers had agreed to make climate change a far greater priority.

Such talk cannot disguise a fundamental problem: there is little oversight or acknowledgment of just how much armies themselves contribute to climate change. “One of the greatest challenges is that we lack numbers,” explains Jens Stoltenberg, NATO’s secretary-general. This lack of data stems from armed forces’ historic reluctance to disclose information that might place limits on military activity.

The Kyoto protocol, adopted by the UN in 1997, was the first international climate-change treaty to commit countries to slashing their greenhouse-gas emissions. But it came with a loophole: military emissions around the world were exempt from reduction obligations, and even from reporting. The exclusion was granted at the request of America, where some insisted that calculating emissions and making them public could create pressure to curtail the country’s military activities and thus represented a security risk. (Despite this, the country ultimately did not ratify the protocol.) Climate change, it seemed, was seen as a lesser danger to the armed forces than climate-change mitigation.

The military exemption was removed by the Paris agreement of 2015. But the signatories agreed among themselves that each would decide individually whether to set specific targets for their armed forces, or whether to separate out military emissions in the reports they make under the United Nations Framework Convention on Climate Change.

The result is that, usually, some military emissions are lumped in with other totals, while others are not calculated at all, explains Louise van Schaik, of Clingendael, a Dutch think-tank. Emissions from buildings and vehicles used by the armed forces might be included in the figures provided for government or transport, for example. And only domestic emissions have to be counted and reported, so the activities of armed forces overseas are excluded. In the American armed forces, 70% of energy consumption comes from moving and using troops and weapons, mostly abroad.

Various groups have tried to estimate the level of greenhouse-gas emissions armed forces are actually responsible for, as opposed to the numbers they report. In February 2021, a report commissioned by a group of left-wing members of the European Parliament tried to work out the bloc’s military emissions, based on military expenditure. They estimated that the total footprint for EU armed forces was 24.8m tonnes of carbon dioxide equivalent (tCO₂e) in 2019 (including estimated emissions from military industrial production.) That is more than three-quarters of the emissions for the whole of Denmark. In 2018, however, the 27 countries of the EU attributed just 4.5m tCO₂e to military activities—roughly 0.1% of the total they emitted that year. France—the EU’s most militarily active member—was estimated to have been responsible for one-third of the EU’s total military emissions in 2019 but had reported none at all.

Similarly, for 2017-18, Britain’s MoD declared it had emitted 942,283 tCO₂e, which made up half of the central British government’s emissions. A report by Scientists for Global Responsibility—a British advocacy and research group—found that the MoD’s total direct emissions were closer to 3m tCO₂e (excluding emissions from the production of equipment or supply chains).

These figures are dwarfed by estimates for America, with the Pentagon thought to be the largest institutional consumer of petroleum products in the world. A paper published in 2019 by Professor Neta Crawford, a political scientist at Boston University, estimated that America’s armed forces emitted 59m tCO₂e in 2017. For comparison, total emissions from all sources and sectors for the whole of Switzerland were 44m tCO₂e in 2018.

In recent years, many Western armies have adopted cleaner technologies—including electric vehicles and renewable energy sources. Others are experimenting with new fuels for aviation: the Dutch Ministry of Defence, for example, is phasing in biofuels (as is America) and now uses them to power all F-16 Fighting Falcon jets from its base in Leeuwarden. In the absence of transparent emissions reporting or targets, this is often trotted out as evidence of their green credentials. But the changes have been driven mostly by the imperatives of operational efficiency and continuity.

Reliance on fossil fuels for energy—once described by General David Petraeus, a former director of America’s CIA, as “the lifeblood of our warfighting capabilities”—creates security risks and threatens missions. Transporting fuel to remote bases typically requires long convoys of military vehicles, vulnerable to enemy attack. Between 2001 and 2010, for example, over half of American casualties in Iraq and Afghanistan occurred during land transport missions. Many of these missions involved the delivery of fuel to remote bases—a study by the Army Environmental Policy Institute published in 2009 estimated that the average load allocation for convoys in the region was 50% fuel. Fossil fuels are also costly: between 2010 and 2018 the American armed forces purchased roughly 100m barrels of fuel each year, with an annual bill of $8bn-17bn. And securing access to the fuel adds more costs still. It is estimated that America’s armed forces spend around $81bn annually defending the global oil supply. Besides the expense, the adoption of green technologies in civilian markets will also drive the armed forces to follow suit.

Despite these pressures, most Western armies are yet to cut their emissions significantly. Meanwhile, climate change is increasingly shaping the environment in which they operate, and the risks for which they are trying to prepare. Higher sea- levels threaten infrastructure: operations at the world’s largest naval base, in Norfolk, Virginia, are regularly disrupted by flooding. Western countries with territories in places susceptible to extreme weather—such as the Caribbean for both Britain and the Netherlands, and the Pacific for France—have also found more demands being made on the armed forces based there to provide humanitarian relief and assistance after disasters. Fears abound about new geopolitical tensions—driven by melting ice in the Arctic, instability caused by migration and resource scarcity as temperatures rise. America is now explicitly incorporating such scenarios into its modelling, simulations and war-gaming; NATO has recently agreed to launch new research into the link between global warming and security.

The result is a curious mixture of resignation and urgency. Britain’s recent climate-change strategy, for example, stated baldly that the country’s armed forces are preparing for a “climate-changed world of between +2 and 4°C” above pre-industrial levels—ie, above the 2°C ceiling set as a target in Paris. But the amount that temperatures will rise depends on progress in reducing emissions. Doing so efficiently requires accuracy and openness about emissions. This is coming at last from military forces themselves. Mr Stoltenberg, for example, recently announced that he wants NATO alliance members to pledge at a summit later this year to make their armies carbon-neutral by 2050 and NATO is currently developing an emissions-reporting methodology to facilitate this. Britain’s MoD has also now promised to set specific targets for reducing its carbon emissions. Lieut-General Nugee’s report, for instance, says that Britain’s sprawling defence estate—the MoD is one of the largest landowners in the country, with hangars, houses and barracks—will reduce emissions by at least 30% by 2025.

The difficulties in balancing armies’ desires for combat effectiveness with the need to cut emissions will persist. Yet attitudes are, slowly, changing. “Climate change makes the world a more dangerous place,” says Mr Stoltenberg. “And therefore it matters to NATO, and therefore we need to be part of the answer to global warming.” Earlier this month, speaking at a climate summit, Mr Austin called the climate crisis an “existential” threat, and pledged that the Pentagon would be “doing our part” to alleviate it.

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