Militaries’ emissions could be bigger than all aviation and shipping combined

The respected international science journal Nature has called on the world’s defence forces to decarbonise, estimating that together military emissions produce up to 2.2billion tonnes of CO2 equivalent a year.

It says armed forces have a massive carbon footprint that is absent from global accounting and emissions reporting.

For the first time, the climate change conference, COP27, will hear from a government about the damage conflicts are doing to the environment and climate.  The Ukrainian government will present a calculation of the financial and environmental costs of the war against Russia.

Nature’s editorial opinion suggests it’s an urgent activity: “The world’s militaries are heavy emitters of greenhouse gases. No one knows exactly how much; estimates range between 1% and 5% of global emissions, comparable with the aviation and shipping industries (2% each). Yet militaries are largely spared from emissions reporting. This must change, or mitigation measures risk becoming mere guesswork.”

How big are militaries’ emissions?

It’s difficult to know, but SPG Global Insights commodity analysts have reported that official data from the Russian energy ministry shows that domestic diesel output started to rise in December and consumption started to increase from February, which coincides with the order to invade Ukraine.

Us use 2
US defence force energy use as illustrated in Nature

“The campaign may be consuming almost 6% of Russia’s total diesel refining output. A possible rough estimate [of the Russian military’s consumption] is around 15 million litres/day for all types of fuel combined, including about a quarter on jet fuel,” George Voloshin of Aperio Intelligence said. There are 160 litres in a barrel of oil.

In 2014 the Institute of Concerned Scientists (UCS) reported that the US Defence forces were using 100million barrels of oil a year. The Watson Institute of International Affairs at Brown University in the US, reported in 2019:

“…the DOD is the world’s largest institutional user of petroleum and correspondingly, the single largest institutional producer of greenhouse gases (GHG) in the world. From FY1975 to FY2018, total DOD greenhouse gas emissions were more than 3,685 Million Metric Tons of CO2 equivalent. While only a portion of US total emissions, US military emissions are, in any one year, larger than the emissions of many countries. In 2017, for example, the Pentagon’s total greenhouse gas emissions (installations and operations) were greater than the greenhouse gas emissions of entire industrialized countries, such as Sweden, Denmark and Portugal and also greater than all CO2 emissions from US production of iron and steel.

(One estimate suggests Australia uses 51bn litres or 319m barrels of oil a year.)

Another Cosmos report on decarbonization of industry: There are plenty of roads to net zero

The Australian Strategic Policy Institute (ASPI) in a special report By Ulas Yildirim and Will Lebenin June this year which focussed on Defence oil security, quoted a 2018 Australian National Audit Office report on Defence’s fuel procurement.  “Fuel is Defence’s largest single commodity expenditure, amounting to an annual spend of approximately $423m in 2016–17,” it stated.

It also provided a breakdown of spending between the services of $2.1 billion spent between 2012 and 2017: $1.4 billion was spent by the Air Force, $630 million by the Navy and $139 million by the Army.

“The internal tanks on an F-35A fighter hold around 8,000 kgs of jet fuel,” ASPI reported.

“The major warships of the Royal Australian Navy (RAN) are unsurprisingly thirsty, too, and two of its previous oilers, HMAS Success and Sirius, carried approximately 9,000 tonnes and 35,000 tonnes of F-76 marine diesel, respectively, for replenishment underway.

“The prospective RAN class of nuclear-powered attack submarines will, in fact, be the only major ADF weapon system not dependent on liquid-fuel supplies. Helicopters, armoured vehicles and the mundane mass of light vehicles and trucks that are key to any military operation also consume large volumes of fuel. There’s currently no use of alternative fuels by the ADF,” ASPI says.

Nature calls for action in four areas on militaries’ emissions.

“First, militaries across the globe must be held accountable.  

Second, militaries must improve their capacity to calculate, manage and reduce emissions.

Third, researchers need to document and understand how armed conflicts impact the climate and society. “This dynamic is complex, but crucial for identifying low-carbon recovery pathways for countries coming into conflict, such as Ukraine, and for understanding the long-range costs of armed conflict.”

And finally, says Nature, “…independent research is paramount to keep militaries accountable and to uphold obligations made under the United Nations Framework Convention on Climate Change.”


Please login to favourite this article.