"Megadroughts" on the rise
This is described in the study published in the journal "Science" by a research team from Switzerland and Austria.
The fact that this also applies here in Germany can be seen in the falling groundwater level, impaired harvests, reduced electricity production in hydroelectric power plants and drought stress for plants and animals - not least in the white ribbons of snow that meander somewhat unromantically through snow-covered landscapes.
In recent years, this phenomenon has constantly alternated with extreme weather events such as heavy rainfall.
The Swiss Federal Institute for Forest, Snow and Landscape Research(WSL) got to the bottom of this relatively new phenomenon with a research team led by Liangzhi Chen and Dirk Karger. The Institute of Science and Technology Austria (ISTA) in Klosterneuburg (Lower Austria) and glacier researcher Francesca Pellicciotti, who works there, were also involved in the analyses.
What was examined?
The long-term relationship between precipitation and estimated evaporation was calculated and the resulting behavior of the vegetation was determined using green components in satellite data.
13,176 multi-year drought events were identified between 1980 and 2018.
The result
According to studies, the phenomenon is increasing. If droughts last for at least two years, the area of land affected increases exponentially. In figures, this means an average increase of almost 50,000 square kilometers.
To get a feel for it: The national territory of Austria is approximately 84,000 square kilometers.
Five of the ten largest drought events occurred between 2007 and 2018.
The method of the study revealed that not only the well-known droughts, such as in the still ongoing Chile, the West and Southwest of the USA (2000 - 2018) or in Central Europe (2018 - 2022) and their enormous damage are documented, but also drought events that are not documented or documented in less detail.
In areas where there are large water reserves to fall back on, a drought often only becomes apparent very late. This is referred to as "paradoxical effects".
