Defra is primarily responsible for making the UK resilient to the impacts of global warming, such as increased flood risk.
A freedom of information request has revealed that the Department for Environment, Food & Rural Affairs (Defra) is cutting spending for "climate change initiatives" to only £17.2m this financial year. This is 41% less than the year before.
It is feared slashing the funds will mean a greater risk of issues related to flooding and other global warming consequences in the UK. Bob Ward, policy director at the London School of Economics' Grantham Research Institute, commented:
"These shocking figures should worry everyone in the UK. Defra is the lead government department for climate change adaptation and is primarily responsible for making the UK resilient to the impacts of global warming, such as increased flood risk."
Paterson 'unfit for office'
Most of the money is spent helping Britain adapt to and cope with the effects of global warming, such as giving advice on how to deal with water shortages, soil erosion, and extreme weather like flooding, as well as research.
The rest is spent on curbing the extent of climate change, for example the monitoring and capturing methane and carbon emissions.
Defra's spending for domestic climate change initiatives now represents just 0.7% of the department's total budget for the year, down from 1.2% last year.
The dramatic cut comes in Owen Paterson's first full-year as Environment Secretary - he took up the post in September 2012.
Friends of the Earth campaigner Guy Shrubsole, said that by cutting Defra's work to protect the UK from extreme weather events and climate change, Paterson shows "he's unfit for office" and "continues to put more people and their livelihoods at risk".
Paterson was also criticised by shadow Environment Secretary, Maria Eagle, who said such a steep drop in funding "reveals an incredible level of complacency about the threat to the UK from climate change".
She said this adds to the evidence that the Environment Secretary's climate scepticism is "leading him to make the wrong choices on spending cuts".
The department's decreased domestic spending on climate change came as its spending overseas increased from £20.1m last year to £30m this year - nearly the same amount as the decline in domestic spending.
Much of the increase is due to an agreement made in September 2012, following the 2010 UN Climate Change Conference in Cancun which required Defra to give £140m to the International Climate Fund, which helps the world's poorest adapt to climate change.
A Defra spokesman said: "Defra funds programmes that help protect international forests, cut greenhouse gas emissions and help the UK adapt to a changing climate."
Sophie Morlin-Yron is a freelance journalist.