UK summer flash floods to become more frequent, study shows

UK summer flash floods to become more frequent, study shows

Fiona Harvey, environment correspondent

The Guardian, Sunday 1 June 2014 13.00 EDT

Flash flooding in summer is likely to become much more frequent across the UK as a result of climate change, with potentially devastating results in vulnerable areas, according to new research.

The study, published in the peer-review journal Nature Climate Change, is the first to draw a direct link between climate change and an increase in summer downpours.

The research, a result of a collaboration between the Met Office and Newcastle University, used climate change computer models and standard weather prediction models of the type used for short-term weather forecasts. It found that summers would be drier overall, but punctuated by more extreme downpours.

These can have a much worse effect than the steady rainfall typical of winter, because the dry land is less capable of absorbing water, and when too much falls in a short period it runs off, causing flash floods of the type that struck Boscastle in 2004, one of the worst examples of sudden localised flooding in recent years.

Elizabeth Kendon of the Met Office, the lead author of the study, said that the research was groundbreaking in using a high-resolution weather forecasting model to translate the likely effects of climate change into a detailed prediction of future UK summer weather.

"Until now, we haven't been able to do it in this way," she said. "This should help people to understand what is likely to happen in the summer in future. It's very important that we've detected this signal for heavier downpours in the UK. It's now for policymakers to decide what to do about it."

Some of the worst results could still be a few decades away, but the effects are already being felt and are likely to grow more severe, according to the models. But Kendon said more accurate predictions would depend on more scientific research being undertaken.