Abstract/Summary

This paper presents a consistent series of policy-relevant indicators of changing climate hazards and resources for the UK, spanning the health, transport, energy, agriculture, flood and water sectors and based on UKCP18 climate projections. In the absence of explicit adaptation, risks will increase across the whole of the UK, but at different rates and from different starting values in different regions. The likelihood of heat extremes affecting health, the road and rail network and crop growth will increase very markedly. Agricultural and hydrological drought risks increase across the UK, as does wildfire danger. River flood risk increases particularly in the north and west. Demand for cooling energy will increase, but demand for heating energy will decline. Crop growing degree days will increase, benefiting the production of perennial crops. In general, the risks associated with high temperature extremes will increase the most in warmer southern and eastern England, but the rate of increase from a lower base may be greater further north and west. Reducing emissions reduces risks in the long term but has little effect over the next two or three decades. The results provide evidence to support the development of national and local climate and resilience policy. Measures to enhance resilience are needed alongside policies to achieve net zero emissions by 2050. Resilience policy should recognise the variability in change in risk across the UK, and therefore different local priorities. Explicit choices need to be made about ‘worst case’ emissions scenarios as they can influence strongly estimated changes in risk: the increase in risk with RCP8.5 can be considerably higher than with a pathway reaching 4 ◦C by 2100.