The climate crisis will wipe at least 1% a year off the UK’s economy by 2045 if global temperatures are allowed to rise by 2C, the government has said. More action would be needed on key areas such as flood defences, restoring natural protections such as peatlands and wetlands, and making the built environment more resilient to extreme weather, ministers said. The government’s third five-yearly assessment of the risks from climate change was published on Monday. While taking what many regarded as a conservative estimate of future risks, the assessment painted a future of drastic disruption and costly impacts from the climate crisis. Damage to the UK’s food production, and to infrastructure, from extreme weather, and the risks of flooding, are all likely to cost more than £1bn a year each. In all, at least eight areas of risk were judged likely to cost more than £1bn a year by 2050 – however, some may cost much more, as the risks were assessed in bands, with more than £1bn the highest available. Many other potential areas of risk, such as risks to business supply chains and to the delivery of health services, and the potential damage to culturally important heritage sites, were judged unable to be fully assessed. Jo Churchill, the minister for climate adaptation, said: “The scale and severity of the challenge posed by climate change means we cannot tackle it overnight, and although we’ve made good progress in recent years there is clearly much more that we need to do. By recognising the further progress that needs to be made, we’re committing to significantly increasing our efforts and setting a path towards the third national adaptation programme, which will set ambitious and robust policies to make sure we are resilient to climate change into the future.” Green campaigners said the predictions showed the government needed to do far more to prepare for the effects of the climate crisis. Doug Parr, policy director at Greenpeace UK, said: “This report makes clear that even modest increases in global temperature will have profound impacts across every aspect of our lives. Adaptation can no longer be an afterthought, action on climate change of all kinds needs to be right at the heart of government policy and programmes.” The costs of cutting greenhouse gas emissions – a renewed focus of political attention, as some backbench Tory MPs have called the net zero target into question amid energy price rises – also looked modest in comparison with the cost of the impacts of climate breakdown, according to analysts. Matt Williams, climate and land programme lead at the Energy and Climate Intelligence Unit, said: “The damage caused to the UK by climate change will be greater than the investments needed to avoid harmful levels of warming.” Signe Norberg, of the Aldersgate Group of businesses supporting sustainability, said: “Investing in a healthier natural environment is key to making the UK more resilient to the impacts of climate change and it will be critical that the government puts forward ambitious and credible targets under the Environment Act as well as a new and comprehensive environmental improvement plan later this year. The UK must also continue its efforts to deliver rapid emission reductions across the economy and beyond just the power sector. Key policy gaps remain in crucial areas, such as energy efficiency, agriculture and land use, and skills.” Labour said the government had failed to reduce emissions and to prepare the country’s infrastructure for the impacts of the climate crisis. Jim McMahon, the shadow environment secretary, said: “After more than a decade in power the Conservatives have failed to build the efficient homes, strengthened flood defences, and resilient natural habitats necessary to tackle the climate crisis. Their lack of action and empty promises are putting people, nature, and our economy at risk.” The government said it was investing £5.2bn to build 2,000 new flood defences by 2027, and increasing the nature for climate fund on peat restoration, woodland creation and management to more than £750m by 2025.