Greenhouse gas emissions of military in peacetime and wars are notoriously overlooked but highly relevant, especially as the world becomes ever more conflict-prone. The UN Framework Convention on Climate Change (UNFCCC) did not until now request or publish robust data for direct emissions from military activities and conflicts as well as indirect emissions from the military ‘value chain’ and reconstruction after conflicts. This is mostly due to the exemption of reporting on military emissions for countries under the Paris Agreement, which is a backtracking from the stricter rules of the Kyoto Protocol.
Direct annual emissions of the military in large countries like the US and the UK reach over 1% of national emissions. The lion’s share of these direct emissions is due to operation of combat aircraft. Residential emissions from military bases and emissions of naval operations are also significant. For arms-exporting or high military spending countries, such as USA and UK, their indirect military emissions from the ‘value chain’ can reach volumes similar to their direct annual emissions.
Emissions from the destruction of natural or man-made carbon stocks during wars can reach hundreds of million t CO2, as was the case with forest destruction in Vietnam and the burning of oil wells in Kuwait. Burning down a large city can emit up to 10 million t CO2.
Indirect emissions due to the need to reconstruct cities and infrastructures after the end of a war can easily exceed 100 million t CO2 if a conflict has led to destruction on a country-wide scale.
Further the indirect emissions caused in 3rd parties not directly involved in a conflict can even surpass the military emissions due to reorientation of energy systems, market forces or policies. A large conflict like the war in Ukraine is likely to be relevant in the short term, as the transition from domestically available fossil fuels will be slowed down. In the medium term, the use of distributed renewables is likely to be accelerated, but large-scale international collaboration to develop large scale renewable sources in remote locations can suffer.
Under the Paris Agreement, rules for reporting of military and conflict-related emissions need to be developed. Both independent reporting of operational emissions of military in peacetime as well as large-scale war-related emissions is to be taken up with high priority. Military emissions should play a relevant role in the Global Stocktake due to be finalized by COP28 in 2023. The IPCC should address the issue both in the context of national inventory guidelines and the 7th Assessment Report cycle, ideally in form of a Special Report.
Collaboration of researchers and civil society organisations, and engagement with committed governments can make use of windows of opportunities created by unprecedented crises.
The vision should be that aggressors should be made liable for war- and occupation related emissions through peace settlements or at least on the UNFCCC level.
The companion advocacy and outreach briefing is available here.