Expect regular flooding disasters, warns Met office
Experts say catastrophic amounts of rainfall could hit the country at least once every three years
BRITAIN should prepare for unprecedented winter rainfall and flooding every three years, the Met Office has said, after running what it claims to be the most comprehensive weather modelling ever on its new supercomputer.
The chance of torrential downpours, such as those that left large swathes of the country under water in the winter of 2013-14, is increasing, say experts, with a one-in-three chance of at least one region being affected annually.
Storms three years ago resulted in the Somerset Levels being severely flooded; the Thames overflowed its banks in Oxfordshire, Berkshire and Surrey; and areas of the River Severn floodplain were left submerged. Thousands of homes were flooded, farmers were forced to evacuate livestock, and railway lines on the south west coast were washed away by tidal surges. Clean-up costs in the Thames Valley alone were estimated to be more than £1 billion. December 2015 brought similarly severe weather, with Storm Des- mond hitting the north west.
Dr Vikki Thompson, lead author of the report, said: “Our computer simu- lations provided one hundred times more data than is available from observed records. Our analysis showed that these [severe storms] could happen at any time, and it’s likely we will see record monthly rainfall in one of our UK regions in the next few years.”
The predictions, published in journal Nature Communications, is based on climate records going back to the Eighties. But crucially, the supercomputer – which can perform more than 16,000 trillion calculations per second, and weighs the equivalent of 11 doubledecker buses – also simulated 3,000 possible winters that could have emerged based on previous weather patterns. It showed there was a 7 per cent risk of record monthly rainfall in south east England in any given winter. The figure rose to 34 per cent when other regions of England and Wales were considered.
Daniel Johns, head of adaptation, Committee on Climate Change, said: “This reinforces our call for the Government to prepare for a significant flood event to take place somewhere in the country almost every year. Evidence is mounting that higher seasonal temperatures, and heavier rainfall, are already affecting the UK.”
Prof Piers Forster, director of the Priestley International Centre for Climate, added: “We expect the odds to shorten on future rainfall extremes but the first stage to predict this is knowing the current odds – and this is what this new paper gives us.”
Bob Ward, policy and communications director at the Grantham Research Institute on Climate Change and the Environment at the London School of Economics and Political Science, said: “I hope that the Environment Secretary will carefully read this important Met Office analysis.”