Britain will experience some of the worst river flooding in Europe in the coming years, according to a major study that looked at half a century worth of data.
Researchers from 24 European countries have provided the clearest evidence yet that climate change is affecting the severity of floods. The study also shows clear regional variations – in northwestern Europe, floods are becoming more severe but will be less destructive in southeastern Europe.
North England and southern Scotland will be the areas worst affected, with an 11 per cent increase in river flood levels per decade, according to the research by 50 scientists from 35 research institutions.
This is because in central and northwestern Europe, increased levels of precipitation are making soils wetter meaning they are unable to absorb excess water, according to the paper published in Nature.
In southern Europe, the risk of flooding is falling because climate change is causing precipitation to fall while higher temperatures are drying out soils, meaning they can absorb more water. Some areas will see as much as a 23 per cent decline in the magnitude of flood events per decade.
In the Mediterranean, small river floods may become larger due to more frequent thunderstorms and deforestation, according to scientists who looked at river flow data from 3,738 locations.
“For a long time, it has been assumed that climate change is having an impact on the magnitude of flood waters because a warmer atmosphere can store more water. However, this is not the only effect – things are more complicated,” said lead researcher Professor Gunter Bloschl from the Vienna University of Technology.
“Processes differ across Europe – but the regional patterns all correspond well with predicted climate change impacts. This shows us that we are already in the midst of climate change,” he said.
Annual damage from flooding costs an estimated $100bn (£80bn) of damage every year. This is expected to rise due to increased economic growth and urbanisation.
“This timely study adds to a growing body of evidence that shows that flood magnitude has increased in the UK over the last five decades, particularly in parts of northern and western Britain,” said Jamie Hannaford from the UK’s Centre for Ecology and Hydrology.
“We show this is part of a continent-wide pattern of changes in flooding, which is in line with what we may expect in a warming world.
“This highlights the importance of long-term hydrological monitoring and the benefits of data sharing and collaboration at a European scale in order to better understand the mechanisms behind observed changes in flooding.”
Researchers say these findings should be included in flood management strategies.
“Regardless of the necessary efforts of climate change mitigation, we will see the effects of these changes in the next decades. Flood management must adapt to these new realities,” said Professor Bloschl.