Global Military / Defense Emissions
The world's militaries collectively emit an estimated ~2.2 Gt CO₂e/yr — roughly 5.5% of global GHG. This is larger than aviation, larger than shipping, and comparable to the annual emissions of Russia or Japan. Yet military emissions are entirely excluded from the Paris Agreement, exempt from national NDC targets, and incompletely reported by every major military power.
This model covers all nations' militaries globally. For US DoD-specific detail (energy by platform, base climate vulnerability, combatant command risk), see:
U.S. Department of Defense — Climate, Energy & EmissionsTotal Global Military Emissions by Scenario (Mt CO₂e/yr)
As % of Global GHG
Military share of global GHG by scenario. If military spending continues rising while global emissions fall, the share grows.
Scenario Summary (2050)
| Scenario | 2050 Total (Mt CO₂e/yr) | vs Baseline | Cumul. 2024–50 (Gt) | Paris Gap (Gt) | Peak Year |
|---|---|---|---|---|---|
| Baseline | 4121 | — | 83.51 | +23.3 | 2050 |
| Nato Pledge | 2878 | -30.2% | 72.54 | +12.33 | 2047 |
| Global Inclusion | 1835 | -55.5% | 60.21 | +0.0 | 2032 |
| Conflict Escalation | 5537 | +34% | 104.3 | +44.09 | 2050 |
Share of Global Military Operational Emissions (2024)
Estimated Operational Emissions by Actor
Operational scope only (excl. supply chain). Sources: CEOBS, SIPRI, Costs of War Project.
Reporting Status by Major Military Power
| Country/Bloc | Paris NDC includes military? | Public inventory? | Supply chain included? | Key limitation |
|---|---|---|---|---|
| United States | No | Partial (Annual Energy Report) | No | Overseas ops, weapons procurement, and base construction excluded |
| United Kingdom | Voluntary target | Annual Sustainability Report | Partial (Scope 3 stated goal) | Only UK committed to net-zero; operational intensity metrics unclear |
| NATO collective | No | No aggregate | No | Climate Security Action Plan 2023 — non-binding, no aggregate target |
| China (PLA) | No | None published | No | No independent verification; estimates based on spending and fleet size |
| Russia | No | None published | No | Conflict emissions (Ukraine) not in any inventory; CEOBS external estimate only |
| EU member states | Varies by country | Varies; fragmented | No | CBAM explicitly exempts military procurement |
| India | No | None published | No | Large army/navy; no public military climate disclosure |
Operational Emissions Only (Mt CO₂e/yr)
Supply Chain Emissions (Mt CO₂e/yr)
Reporting Framework Coverage (%)
% of global military emissions covered by any binding international framework. Currently ~2% (some NATO voluntary reporting).
Reduction vs Baseline (%)
Scenario Descriptions
| Scenario | Key Assumptions | 2050 Outcome | Probability Assessment |
|---|---|---|---|
| Baseline | Military spending grows ~3.7%/yr; efficiency gains ~0.8%/yr; no new reporting frameworks; Paris exemption continues | ~3,500 Mt CO₂e/yr by 2050 | Most likely absent political change; historical trend extrapolation |
| NATO Pledge | NATO members (~50% global mil spending) meet 2030 commitments: 100% SAF by 2040, EV ground fleet by 2035, net-zero installations by 2030; non-NATO continues baseline | ~2,100 Mt CO₂e/yr by 2050 | Low-to-medium; commitments are non-binding; SAF supply constraints |
| Global Inclusion | Paris Agreement expanded from 2028 COP to include military NDC targets; all major emitters face binding ~2.5%/yr reduction requirements | ~800 Mt CO₂e/yr by 2050 | Low; requires US, China, Russia consensus — historically blocked |
| Conflict Escalation | Major conflict 2026–2032 (Taiwan/NATO scale); 80 Mt/yr additional conflict emissions; post-conflict spending acceleration; no new accountability frameworks | ~4,500 Mt CO₂e/yr by 2050 | Tail risk; conflict emissions would temporarily exceed entire aviation sector |
Conflict Scenario: Stacked Emissions (Mt CO₂e/yr)
Orange layer = conflict-induced emissions above operational baseline.
Historical Conflict Emission Estimates
| Conflict | Duration | Est. Total Mt CO₂e | Mt/yr | Note |
|---|---|---|---|---|
| Gulf War (1990–91) | 1 yr | ~100 | ~100 | Oil well fires; Kuwaiti infrastructure |
| Iraq War (2003–2011) | 8 yrs | ~400 | ~50 | Crawford (Brown Univ.) — includes US ops + reconstruction |
| Afghanistan (2001–2021) | 20 yrs | ~350 | ~18 | Lower intensity; long duration |
| Syria Civil War (2011–ongoing) | 12+ yrs | ~230 | ~19 | Infrastructure destruction; multiple parties |
| Ukraine conflict (2022–) | 2+ yrs | ~300+ | ~150 | CEOBS 2023; highest-intensity modern conflict |
Sources of Conflict Emissions
Direct military operations
Jet fuel (JP-8/Jet-A) for sorties and transport; diesel for vehicle manoeuvre; artillery propellant; naval fuel consumption; temporary generator sets. Typically 30–40% of total conflict emissions.
Infrastructure destruction
Fires in energy facilities (oil wells, refineries, power plants) release concentrated stored carbon. Damaged buildings release embodied carbon. Gaza/Ukraine: extensive energy infrastructure targeted directly. 40–50% of conflict total.
Post-conflict reconstruction
Rebuilding with cement, steel, and glass is extremely carbon-intensive. A destroyed mid-rise building requires ~500 tCO₂ to rebuild. Ukraine reconstruction estimated 750 Gt total (World Bank); emissions tail lasting 15–25 years.
The Aviation/Shipping Comparison
| Sector | Est. GHG (Gt CO₂e/yr) | % Global | Binding framework? | Status |
|---|---|---|---|---|
| Aviation | ~1.0 (CO₂ only) / 2.5 (incl. non-CO₂) | ~2–5% | Yes — CORSIA (ICAO) | Phased market mechanism; SAF mandates |
| Shipping | ~0.7–1.0 | ~2–3% | Yes — IMO 2050 strategy | Net-zero by 2050 target adopted 2023 |
| Military (global) | ~2.2 | ~5.5% | No — no framework | Excluded from Paris; no sectoral body |
Why Inclusion Is Difficult
Sovereignty argument: States argue military operations are sovereign activities, and emissions reporting would reveal classified capabilities (aircraft numbers, sortie rates, fuel logistics).
Operationalisation problem: A fighter sortie in a training exercise versus a combat mission has the same emissions but very different geopolitical framing. Attribution is contested.
Great power veto: US, China, and Russia together represent ~60% of global military emissions. None has supported inclusion. Without them, any framework would be symbolic.
NATO internal tension: Smaller NATO members (Nordic, Benelux) support reporting; larger members resist binding targets fearing operational constraints.
Pathways to Accountability
1. Voluntary reporting norm
Build critical mass of nations publishing military GHG inventories (UK leads; Sweden, Netherlands have partial). Create peer pressure. Timeline: 5–10 years. Does not constrain emissions but establishes baseline data.
2. Technology mandate approach
Require SAF blending mandates, building efficiency standards, and EV ground fleet transitions — as technology standards rather than emissions caps. Avoids classified data issues. NATO Climate Security Action Plan (2023) takes this approach.
3. Paris NDC inclusion
Revise Paris Agreement reporting guidance to require military in NDCs. Would need consensus at COP; US, China, Russia historically block. Possible leverage: small island states + EU + UK bloc could table formal proposal at COP33 (2028).
Key Milestones in Military Emissions Accountability
| Year | Event | Detail |
|---|---|---|
| 1997 | Kyoto Protocol military exemption | US negotiators secured exclusion of international military operations from GHG reporting obligations. Exemption carried into all subsequent UNFCCC agreements. |
| 2015 | Paris Agreement — military remains excluded | COP21 maintains voluntary-only military reporting. No country's NDC includes binding military emission reduction targets. The exclusion is not mentioned in the text. |
| 2019 | Crawford (Brown Univ.) — US DoD analysis | First systematic accounting of full US DoD footprint: 59 Mt CO₂e reported, but ~250 Mt with supply chain. Paper catalyses global accountability discussion. |
| 2021 | CEOBS global military estimate published | Conflict & Environment Observatory estimates global military at minimum 5.5% of global GHG (~2.7 Gt CO₂e). Notes systematic under-reporting. |
| 2021 | UK Ministry of Defence — net-zero by 2050 target | First major military to set net-zero target including Scope 3. Commitment covers estate, fleet, and supply chain. No enforcement mechanism. |
| 2022 | Ukraine conflict emissions surge | CEOBS estimates 150 Mt CO₂e in first year of conflict — equivalent to Belgium's annual emissions. Conflict emissions absent from any national inventory. |
| 2023 | NATO Climate Security Action Plan | NATO Vilnius Summit adopts Climate Security Action Plan. Non-binding; encourages member reporting. No aggregate military emissions target. |
| 2024 | SIPRI: global military spending $2.44 trillion | 9th consecutive year of increase. Real-terms growth accelerating post-Ukraine. Emissions tracking lags spending by ~3–5 years. |
| 2025 | EU Carbon Border Adjustment — military exemptions | EU CBAM explicitly exempts military procurement. Critics note this creates a carbon pricing gap for one of Europe's largest procurement sectors. |
| 2028 | COP33 — Paris military inclusion debate expected | Multiple NGOs and small-island nations have tabled proposals to include military NDCs. US, Russia, and China historically block; post-2024 geopolitical alignment unclear. |
Sources & References
| Source | Description | Key Contribution |
|---|---|---|
| Crawford (2019, updated 2022) | Brown University Costs of War Project | First comprehensive US DoD footprint: ~59 Mt ops, ~250 Mt with supply chain; Iraq War ~400 Mt total |
| CEOBS (2021) | Conflict & Environment Observatory — Global Military Emissions | ~5.5% of global GHG; country-level estimates; systematic under-reporting analysis |
| SIPRI Military Expenditure Database (2023) | Stockholm International Peace Research Institute | $2.44T global spending; 9-year growth trend; country breakdowns for proxy emissions |
| Belfer Center (2023) | Harvard Kennedy School — NATO Military Decarbonisation Pathways | SAF transition feasibility; electrification timelines; cost premiums for green military fuels |
| UNFCCC Reporting Analysis (Dencik & Ware 2022) | Military emissions and the Paris Agreement transparency framework | Legal analysis of Kyoto exemption carry-over; NDC gap quantification; reform pathways |
| CEOBS Ukraine Report (2023) | Environmental impact of the conflict in Ukraine — 12-month assessment | ~150 Mt CO₂e first year; methodology for real-time conflict GHG attribution |
| DoD Annual Energy Management Report FY2023 | US Department of Defense | 57 Mt CO₂e reported (ops scope 1+2); $20B energy spending; fuel breakdown by platform |
| World Bank Ukraine Reconstruction (2023) | Rapid Damage and Needs Assessment | $750B+ reconstruction estimated; embodied carbon implications for post-conflict emissions |