International climate finance instead of weapons of mass destruction

This is an extract from our report “Nuclear Weapons, the Climate and Our Environment”.

Rich nations are disproportionately responsible for causing the climate crisis due to their historically high levels of carbon emissions,[1] but developing nations are more vulnerable to the impacts of the crisis. Climate finance is financing from public and private sources that is provided by developed nations to developing nations to help those nations reduce carbon emissions and adapt to the effects of climate change.

Developed nations promised to make US$100 billion in public and private climate finance available to developing nations by 2020.[2] This commitment has not been met and the latest figures suggest that nine nations spend more public money on nuclear weapons every year than all the world’s developed nations are providing to the developing world in the form of public climate finance.

The Organisation for Economic Co-operation and Development reports that developed nations provided US$54.5 billion in public climate finance in 2017.[3] Figures for the last two years are not available yet but previous annual increases suggest that the figure will have increased to approximately US$66 billion in 2019.[4] Meanwhile, the International Campaign for the Abolition of Nuclear Weapons (ICAN) estimates that the world’s nuclear-armed nations together spent US$73 billion their nuclear forces in 2019.[5] This figure is set to increase further in the coming years as these nations upgrade their nuclear weapons systems (see section 2.1).

The UK government has committed to spending £2.32 billion a year on international climate finance for five years starting in 2021.[6] During this period, the annual cost of the UK’s military nuclear programme will be approximately £7.4 billion per year.[7] That means that during the last decade that the world has left to avert climate catastrophe,[8] the UK will spend three times more on its military nuclear programme than it will spend on international climate finance (see figure 3).

uk climate fn v nukes

The United States has emitted more carbon dioxide to date than any other country.[9] The US is responsible for 25% of global historic emissions, which is twice more than the next largest national emitter, China. However, the US allocated just US$2.5 billion towards climate finance in its 2020 budget,[10] a tiny fraction of the US$37.2 billion allocated to nuclear weapons[11] (see figure 4). The country is set to spend upwards of US$1.2 trillion dollars maintaining and upgrading its nuclear arsenal over the next 30 years.

us spending

If rich nations like the UK, US and France agreed to relinquish their nuclear arsenals, some of the money saved could be provided to developing nations in the form climate finance. This would provide a level of justice to nations that did not cause the climate crisis but are now bearing the brunt of its effects, including low-lying Pacific islands the Republic of Kiribati and the Marshall Islands which were devastated by the nuclear weapons testing of these three states (see section 3.2).

This action would also do more to promote international peace and security than any amount of spending on weapons. Nuclear disarmament would help to quell the interstate rivalry that is blocking action on the climate emergency (see section 2). The extra assistance provided to developing nations would leave them better able to cope with the challenges of global heating, such as disruption to food supplies caused by drought, and would thus reduce the risk of internal conflict and nation state collapse.

[1] H Ritchie, “Who has contributed most to global CO2 emissions?” (Our World In Data, 1 October 2019):

[2] This commitment was agreed at the 2009 United Nations Climate Conference (the Copenhagen Summit) and reaffirmed at the 2015 United Nations Climate Conference in Paris.

[3] “Climate Finance Provided and Mobilised by Developed Countries in 2013-17” (OECD, September 2019):

[4] Between 2013 and 2017, public climate finance increased by an average of 9.8% a year:

[5] “Enough is Enough: Global Nuclear Weapons Spending 2019” (ICAN, May 2020):

[6] “UK aid to double efforts to tackle climate change” (UK government press release, 23 September 2019):

[7] Calculated using ICAN’s methodology (Enough is Enough), ie annual nuclear operating costs plus “Defence Nuclear Enterprise” (DNE) equipment and support costs (note: this includes costs related to the UK’s nuclear-powered attack submarines, as well as the new nuclear-armed Dreadnought submarines). The annual nuclear operating costs in 2020-21 will be £2.4 billion (see I Davis, “How much does the UK spend on nuclear weapons?” (BASIC, November 2018)). The National Audit Office estimates that DNE costs will be £50.9 bn between 2018 and 2028 which works out at £5 billion a year on average. £2.4 bn + £5 bn = £7.4 bn. For alternative methodologies used to calculate the cost of the Trident successor programme over its lifetime, see D Cullen, “Trouble ahead: risks and rising costs in the UK nuclear weapons programme” (NIS, April 2019): and “The Costs of Replacing Trident” (CND):

[8] “Special Report on Global Warming of 1.5°C” (UN Intergovernmental Panel on Climate Change, October 2018):

[9] H Ritchie and M Roser, “CO2 and greenhouse gas emissions” (Our World In Data):

[10] J Thwaites, “2020 Budget Shows Progress on Climate Finance, But US Continues to Fall Behind Peers” (30 January 2020):

[11] “U.S. Nuclear Budget Skyrockets” (Arms Control Association, March 2020):