Oliwier Sahm

Abstract

The main research aim was to determine changes in synoptic conditions during rainfall incidents that led to catastrophic flood events in south-western Poland in 1997, 2010 and 2024. The synoptic analysis was based on data from the ERA5 (ECMWF – European Center for Medium-Range Weather Forecasts) reanalysis containing information on such variables as atmospheric pressure, geopotential, moisture content or direction and speed of air flow in the lower troposphere. The study also includes information on hydrological conditions on the rivers covered by the gauge stations (IMGW-PIB), specifying the height of the exceedance of the alarmcondition and the number of days. As a result of the analysis, it was found that the spatial distribution and accumulation of precipitation caused by the migration of the low-pressure system from over the Gulf of Genoa was significantly influenced by the blocking high. The presence of a jet stream and atmospheric fronts associated with forming shallow lows within the main low baric center was also a supporting factor. In addition, the elevated sum of accumulated precipitation associated with the 2024 rainfall incident again signals a problem related to the rapid warming of the Mediterranean Sea, affecting the overall sum and distribution of precipitation in Europe.

Keywords: flood, precipitation, severe weather, climate change, Poland

Sławomir Sulik [sulik@umk.pl], Department of Meteorology and Climatology, Faculty of Earth Sciences and Spatial Management Nicolaus Copernicus University Lwowska 1, 87-100 Toruń: Poland; Skywarn Poland Warsaw: Poland
Szymon Walczakiewicz [szymon.walczakiewicz@usz.edu.pl], Institute of Marine and Environmental Science University of Szczecin Mickiewicza 16, 70-383 Szczecin: Poland; Skywarn Poland Warsaw: Poland
Małgorzata Świątek [malgorzata.swiatek@usz.edu.pl], Institute of Marine and Environmental Science University of Szczecin Mickiewicza 16, 70-383 Szczecin: Poland
Oliwier Sahm [319581@stud.umk.pl], Faculty of Earth Sciences and Spatial Management Nicolaus Copernicus University Lwowska 1, 87-100 Toruń: Poland