A new study identifies nine specific large-scale weather patterns that influence extreme precipitation over the Mediterranean. Making use of this connection between localized extremes and large-scale weather variability can help to better predict heavy rainfall up to three weeks ahead.
Researchers at the European Centre for Medium-Range Weather Forecasts (ECMWF, UK) and TU Bergakademie Freiberg (Germany) presented their results in the current issue of the International Journal of Climatology.
Extreme rainfall has devastating consequences for societies and economies. Locations around the Mediterranean are frequently affected by such events, leading to landslides and floods. “It is, however, extremely challenging to forecast many days in advance when and where exactly heavy rainfall will occur. Thus, researchers strive to develop new tools to better predict extreme weather phenomena allowing for early warnings and adequate mitigation strategies”, explains first author Nikolaos Mastrantonas, who has carried out the study as a PhD student within the EU-funded research project CAFE.
Learning from the past to shine a light on the future
The researchers analysed weather data from 1979 to today, grouping the daily weather into nine patterns of distinct atmospheric characteristics over the Mediterranean. The study shows that there is a strong relation between these nine patterns and the location of the extreme weather event. “We can now use the data to come up with a model that will help to better predict extreme rain in the Mediterranean”, says Prof. Jörg Matschullat of TU Bergakademie Freiberg. The geoecologist supervises Nikolaos Mastrantonas’ PhD and adds: “When it comes to climate, the Mediterranean Sea is a particularly interesting region as it is surrounded by large continents and mountain ranges. The regional climate of the area is also dependent on large-scale patterns over the Atlantic Ocean, the Balkans and the Black Sea”.
Read more at University of Freiberg / TU Bergakademie Freiberg
Image: (a) Orography of studied area, (b) Intensity of extreme daily precipitation across the domain. (Credit: Mastrantonas et al, 2020)