Heavier Summer Downpours Expected

Extreme summer rainfall may become more frequent in the UK due to climate change, according to new research led by Newcastle University and the Met Office.

The new study, from the joint Met Office and NERC funded CONVEX project which is led by Newcastle University's Professor Hayley Fowler, uses a state-of-the-art climate model providing the first evidence that hourly summer rainfall rates could increase.

While summers are expected to become drier overall by 2100, intense rainfall indicative of serious flash flooding could become several times more frequent.

The results from the study, published in Nature Climate Change, are the first step towards building a more complete picture of how UK rainfall may change as our climate warms.

Prof Hayley Fowler, from Newcastle University’s School of Civil Engineering and Geosciences, said: "We need to understand about possible changes to summer and winter rainfall so we can make informed decisions about how to manage these very different flooding risks in the future.

"The changes we have found are consistent with increases we would expect in extreme rainfall with increasing temperatures and will mean more flash floods."

Dr Lizzie Kendon, lead author of the research at the Met Office, said: "Until now, climate models haven’t been able to simulate how extreme hourly rainfall might change in future. The very high resolution model used in this study allows us to examine these changes for the first time.

"It shows heavier summer downpours in the future, with almost five times more events exceeding 28mm in one hour in the future than in the current climate – changes we might expect theoretically as the world warms. However, we need to be careful as the result is only based on one model - so we need to wait for other centres to run similarly detailed simulations to see whether their results support these findings."

(CVS/CD)