The amount of damage caused by flooding each year in some parts of the UK will increase by 25 per cent even under the best of climate scenarios, according to a modeling study.
paul bates other oliver wing at the University of Bristol, UK, and colleagues built a climate model that simulates the flow of water over land surfaces and used it to estimate how much flooding the UK would experience up to 2070 based on various increases in global temperature.
They estimated the potential cost of flood damage based on insurance data on property values in areas that are currently at risk of flooding and those that may be at risk in the future. “It is unfortunate that the quantification of the impact often has to be in pounds and dollars,” says Wing. “Floods can have serious mental health implications, but these effects are more difficult to estimate.”
The team estimates that flooding currently causes £740 million of damage every year in the UK, and this has increased by 1.4 per cent since 1990.
The world is currently on track for average temperatures to reach 2.5°C above pre-industrial levels by the end of the century.
However, if countries deliver promised emissions reductions on time and global temperatures only rise by 1.8°C above pre-industrial levels, the researchers found that the average annual amount of damage from flooding in the UK would only increase. by 4 percent compared to 1990 levels.
“It’s a pretty modest increase,” says Bates. But this figure hides the fact that some parts of the country will face much worse flooding than others, he says. For example, parts of south-west Wales will face a 25 per cent increase in flood damage, even in the best-case scenario of rising temperatures, says Bates.
But if the promised reductions are not met, higher global temperatures will lead to more flood damage in the UK, the team found. With warming of 2.5°C, average annual flood damage in the UK is projected to increase by 13%. If the global temperature increases 3.3 °C, it would increase by 23%.
Rising temperatures also mean extreme flood years are likely to be more extreme and experience more damage. With a warming of 3.3°C, those years would be 40% more damaging than what are currently considered once-in-a-century events.
The parts of the country that face the greatest risk of flood damage in the future are those that face the greatest risk today, Bates says. These include south east England, north west England, south Wales and central Scotland, she says.
Bates says the inquiry should compel the UK to take a leading role in ensuring countries do not renege on their climate commitments. “We need to make sure that COP26 and the net-zero pledges that different countries have signed up to are actually implemented,” she says.
“This is an impressive study using the best models available to the insurance industry, which have been carefully validated against observed flooding,” he says. jim hall at Oxford University.
“The risk of flooding in the UK will increase due to climate change impacts that have already been ‘locked in’ with carbon emissions now in the atmosphere. If we don’t vigorously mitigate carbon emissions, things will get worse this century,” she says.