The relationship between global climate change and the occurrence of floods is extremely complex and has so far been one of the least researched areas of climate change. For a long time it was unclear whether there was any causal connection between global warming and flooding. A recently published study now clearly shows the concrete effects of global warming on the number and intensity of floods. In the international study, the data from over 3,700 water measuring points from the 50 measuring years in the period 1960 and 2010 were evaluated.
Climate researchers have long suspected that climate change has a significant impact on the amount of water during flood events. The reasons for this are the scientific facts that an atmosphere heated up by global warming can store more water and that sooner or later this water has to be released again by rain.
The clear conclusion of the study is that large-scale river flooding will increase in the future due to the consequences of climate change in Central and Northwest Europe. The reasons for this are diverse. First, the weather models forecast increased rainfall in autumn and winter. Due to the climate change caused by global warming, hot summers and droughts will increase throughout Central Europe and thus also in Germany. The heavy rains in the autumn and winter months thus hit partially very dry soils that are no longer able to absorb the large water masses. Large floods can follow from this.
Secondly, climate researchers predict increasing heavy rain in the coming decades, which can lead to flooding in many places. The reasons for this are the strong regulation of German rivers and the lack of natural overflows in many places. Especially in densely populated areas, the flooding caused by heavy rain can lead to considerable damage. River floods cause approximately $ 100 billion in damage worldwide each year, and the trend is rising. Flood management will have to adapt to these new realities in the coming years. Otherwise, it can be expected that annual flood damage as a result of climate change will increase faster than in previous years.
And thirdly, climate researchers are also seeing changes in atmospheric circulation as a result of climate change. One of the consequences that global warming appears to have on the weather is the slowdown in low-pressure areas across Northern and Central Europe. These low pressure areas therefore have more time to report their rainfall, which in turn leads to an increased risk of flooding.
In addition to the increasing risk of river flooding, coastal regions are also affected by increasing flood events. The background for this is the rising global sea level and the increased intensity of storms due to climate change. According to a new calculation model, around 300 million people in coastal areas will be affected by floods by 2050. This applies not only to very flat countries, mainly in Asia, but also to the entire German North Sea coast. Both the East Friesland region in Lower Saxony and the North Friesland region in Schleswig-Holstein will have to prepare for the increasing flood risk in the coming decades