The Gap In Military Emissions Reporting
Global greenhouse gas accounting has made considerable progress over the past two decades. Corporate reporting frameworks have matured, mandatory disclosure regimes are being introduced across major economies, and the tools available to measure and verify emissions have improved significantly. Against this backdrop, one gap remains largely unaddressed: the emissions generated by the world’s military sectors.
The Scale of Military Emissions
Estimating military emissions with precision is difficult precisely because reporting is so incomplete. However, the available research points to a substantial figure.
Scientists for Global Responsibility (SGR) estimate that the global military sector — including emissions from bases, equipment manufacturing and supply chains — produces approximately 2.75 billion tonnes of CO₂ equivalent per year. This represents around 5.5% of global greenhouse gas emissions. To contextualise that figure: if the world’s militaries were a single country, they would rank as the fourth largest emitter on Earth.
A 2025 study published in Nature Communications found that rising military expenditure has contributed measurably to global CO₂ emission intensity, accounting for an estimated 27% of the total change in CO₂ emission intensity between 1995 and 2023.
Global military spending reached a record $2.7 trillion in 2024, with Stockholm International Peace Research Institute (SIPRI) reporting a 9.4% year-on-year increase — the steepest rise since at least the end of the Cold War. SGR analysis indicates that an additional $100 billion in global military spending is projected to increase the global military carbon footprint significantly.
What Is — and Isn’t — Being Reported
Under the United Nations Framework Convention on Climate Change (UNFCCC), reporting on military emissions is voluntary. This has created a substantial and persistent gap in official climate data.
Research by Scientists for Global Responsibility, published in November 2025, found that official data on military greenhouse gas emissions — even from those countries with the most developed reporting practices — covers on average less than 10% of a military’s estimated carbon footprint when Scope 1, 2 and 3 emissions are included.
The Conflict and Environment Observatory (CEOBS) tracks what the top 60 military spending nations report to the UNFCCC. Their 2025 analysis found that reporting is, if anything, getting worse. The three largest military spenders — the United States, China and Russia — either fail to submit data or provide figures that are incomplete or not disaggregated from civilian sources. Despite spending over $916 billion on its military in 2023, the United States did not submit any emissions inventory report to the UNFCCC for its 2025 submission covering 2023 data.
This reporting gap has deep roots. In 1997, the United States government indicated it would only sign the Kyoto Agreement if its military was explicitly exempt from emissions reporting and reduction requirements. That position has shaped the UNFCCC’s treatment of military emissions ever since.
A 2026 peer-reviewed paper in Renewable and Sustainable Energy Reviews developed the first carbon baseline for military infrastructure using direct measurement, finding that Scope 3 emissions at a single military base were estimated to be between 2.4 and 9 times higher than its combined Scope 1 and 2 emissions — a ratio that illustrates the scale of what is currently not being counted.
Australia’s Position
Australia is among a small number of countries that publishes some military emissions data. SGR’s analysis included Australian data in its assessment of the gap between what is reported to the UNFCCC and what governments publish in their own defence ministry reports. However, even Australia’s reporting covers only a fraction of its military’s estimated total carbon footprint, with Scope 3 emissions largely absent from official figures.
The Corporate Contrast
There is a notable asymmetry between the reporting obligations placed on private sector organisations and those that apply to militaries. Many of the world’s largest defence technology companies — including Lockheed Martin, BAE Systems, Raytheon Technologies and Thales — appear on the Net Zero Tracker, the Carbon Disclosure Project and the Transition Pathway Initiative. Some have set net zero targets and publish detailed emissions data.
The companies that supply equipment to militaries are, in many cases, subject to more rigorous ESG reporting expectations than the militaries themselves. The International Court of Justice ruled in July 2025 that military activities contribute to climate change and that countries have a legal duty to consider their armed forces’ emissions and prevent environmental damage — a ruling that may, over time, increase pressure on governments to bring military reporting into alignment with the standards applied to other large emitters.
Our View
Without more complete emissions profile reporting from military organisations, it is difficult for countries to fully understand their contribution to climate change. Data gaps in emissions reporting are not unusual — they exist across many sectors, particularly in early stages of disclosure maturity. However, given the estimated scale of military-related carbon emissions, this particular gap appears to be material in the context of global climate accounting.
It is likely both a data issue and a governance issue. Militaries are, by their nature, security-focused institutions with legitimate reasons for maintaining confidentiality around operational activities. At the same time, the reporting frameworks that exist for other large-scale emitters suggest that a more systematic approach to measuring and disclosing military emissions — at least at an aggregate level — is achievable. Norway’s defence sector provides one example of what more comprehensive reporting can look like in practice.
The integrity of global emissions accounting depends on consistent coverage of all significant sources. As mandatory disclosure frameworks mature, the treatment of military emissions is likely to receive increasing scrutiny.
Sources
- Scientists for Global Responsibility (SGR), Most Militaries Report Less Than 10% of Their Carbon Footprint, November 2025, sgr.org.uk
- Scientists for Global Responsibility (SGR), Military Spending Rises and Greenhouse Gas Emissions: What Does the Research Say?, September 2025, sgr.org.uk
- Conflict and Environment Observatory (CEOBS), New Data Reveals the Military Emissions Gap is Growing Wider, November 2025, ceobs.org
- CEOBS / Military Emissions Gap, 2025 UNFCCC Military Emissions Data Analysis, militaryemissions.org
- Dong, W., Ran, Q., Liu, F. et al., Rising Military Spending Jeopardizes Climate Targets, Nature Communications, Vol. 16, No. 4766, May 2025, doi.org/10.1038/s41467-025-59877-x
- Hicks, C. et al., Carbon Accounting: Review and Case Study on the Development of a Carbon Baseline for Military Infrastructure, Renewable and Sustainable Energy Reviews, Vol. 227, February 2026, doi.org/10.1016/j.rser.2025.116511
- Medical Association for Prevention of War (Australia), Military Carbon Footprint Grows, February 2026, mapw.org.au
- CEDARE, Contribution of Military and War to Global Emissions, November 2025
- Stockholm International Peace Research Institute (SIPRI), World Military Expenditure Data 2024, sipri.org
- International Court of Justice, Advisory Opinion on Obligations of States in Respect of Climate Change, July 2025
- UNFCCC, National Inventory Submissions 2025, unfccc.int
- Climate Change Performance Index / Military Emissions Gap, How Military Emissions Impact Global Warming, November 2024, ccpi.org
Anabranch ESG Advisory provides independent advice on ESG strategy, climate disclosure, and sustainability reporting. The information in this article is general in nature and does not constitute legal or financial advice. The data cited reflects estimates from third-party research organisations where official reporting is incomplete or unavailable.
