Could one Trident submarine cause ‘nuclear winter’?

The paper examines the climatic risks of nuclear war, updating the 'nuclear winter' concept with modern climate modelling. It argues that even a regional conflict or the deployment of a single UK Trident submarine could cause significant global cooling, disrupt agriculture, and lead to mass starvation. The author concludes that any arsenal exceeding 5MT poses a global climatic threat and calls for the cessation of the UK's Trident replacement programme.

• Modern climate simulations indicate that large-scale nuclear conflicts would cause an average global cooling of 3.5-8ºC, a temperature drop comparable to an Ice Age, with the maximum cooling lasting three to four years and a full recovery taking approximately seven years.
• A large-scale nuclear conflict would severely impact key crop-growing regions; in Iowa and Ukraine, simulations show temperatures below freezing for two years and a halving of the growing season, respectively, alongside a 50-70% reduction in rainfall.
• A 'regional conflict' involving 100 Hiroshima-sized nuclear weapons (1.5MT total) could inject 5Tg of soot into the atmosphere, resulting in global cooling for ten years peaking at 1.3ºC.
• A single UK Trident submarine, carrying 48 warheads of 100kT each, could devastate an area 192 times that of Hiroshima. Depending on the model used, it could inject between 9.6Tg and 38.4Tg of soot into the atmosphere, potentially causing a global average cooling of 1.5-3ºC for at least five years and shortening growing seasons by 10-30 days.
• The author asserts that any nuclear arsenal exceeding approximately 5MT (roughly 50 Trident warheads) should be viewed as a global threat due to potential climatic impacts. The five official nuclear powers (USA, Russia, China, France, and the UK), and possibly Israel, India, and Pakistan, possess arsenals exceeding this level.

APA

Webber, P. (2008). Could one Trident submarine cause ‘nuclear winter’? Scientists for Global Responsibility. https://www.sgr.org.uk/sites/default/files/2019-04/NL35_NuclearWinterTrident.pdf

Chicago

Webber, Philip. Could one Trident submarine cause ‘nuclear winter’? Scientists for Global Responsibility, 2008. https://www.sgr.org.uk/sites/default/files/2019-04/NL35_NuclearWinterTrident.pdf.

Wikipedia

{{cite report |last1=Webber |first1=Philip |title=Could one Trident submarine cause ‘nuclear winter’? |publisher=Scientists for Global Responsibility |date=2008 |url=https://www.sgr.org.uk/sites/default/files/2019-04/NL35_NuclearWinterTrident.pdf |access-date=23 October 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{webber2008could, author = {Webber, Philip}, title = {{Could one Trident submarine cause ‘nuclear winter’?}}, institution = {Scientists for Global Responsibility}, year = {2008}, url = {https://www.sgr.org.uk/sites/default/files/2019-04/NL35_NuclearWinterTrident.pdf}, urldate = {2026-10-23}, note = {Indexed by Climate Insights Directory} }