Has Climate Change Impacted the Timing of European Floods?

The timing of floods has changed significantly across certain areas of Europe, according to a study conducted by TU Wien and 30 European partners. Climate change is often blamed when a major flooding event occurs, yet it is still uncertain whether climate change is a primary factor causing river floods in certain parts of Europe. 

Prof. Guenter Bloeschl from the Institute of Hydraulic Engineering and Water Resources Management at TU Wien conducted a large international project, where he gathered and analysed 50 years of data from 4,000 hydrometric stations across 38 European countries. He discovered that climate change does have a significant impact on certain European regions. The data collected shows how, over the years, there has been change in the timing of floods. Floods occur earlier or later in certain regions, depending on the cause of the flood event. 

Bloeschl and his team looked closely at the timings of different flood events within regional parts of Europe to try and understand the link between climate and floods. From the study, Bloeschl discovered that in the winter months, north-west Europe and the mediterranean would experience more flooding, this is due to low evaporation and intense precipitation. Whereas in Austria, the summer months are when flooding is most likely to occur because of summer downpours. 

Flood data from all regions of Europe have been collected, compiled and analysed. The results indicate that over the last 50 years, flooding in Europe has drastically shifted. 

Bloeschl said: "In the north-east of Europe, Sweden, Finland and the Baltic States, floods tend to strike one month earlier than in the 1960-1970s, back then they usually occurred in April, but now they occur in March, this is due to snow melting earlier in the year, because we are now experiencing a warmer climate."

An ERC Advanced Grant awarded to Bloeschal in 2012, contributed to the advancements in flood research. The grant helped him establish a vast array of international co-operations across Europe, which helped him examine the link between floods and climate change.