The influence of atmospheric circulation on the occurrence of dry and wet periods in Central Poland in 1954–2018

Abstract

This work presents the influence of atmospheric circulation on the occurrence of dry and wet periods in the central Polish region of Kujawy. The material on which the authors relied encompassed monthly totals of precipitation obtained from 10 weather stations in the period 1954–2018. Both dry and wet periods have been identified on the basis of monthly values of the Standardised Precipitation Index (SPI). Additionally, the calendar of circulation types over Central Poland was used to determine the atmospheric circulation indices: western (W), southern (S) and cyclonicity (C). The analyses have indicated that the region concerned experiences low precipitation totals in comparison with the rest of Poland. According to the circulation indices W, S and C, for Central Poland, the air mass advection from the West prevails over that from the East. Moreover, a slightly more frequent inflow of air from the South than from the North has been observed. The frequency of anticyclonic situations is higher than that of the cyclonic types in this part of Europe. Drought spells occurred in the study area at a clear dominance of anticyclonic circulation, with the inflow of air mostly from the North and with increased westerly circulation. On the other hand, the occurrence of wet periods was mainly influenced by cyclonic circulation during the advection of the masses from the South and West. Dry and wet periods accounted for 28% and 27% of the study period, respectively.

Hydrological Dry Periods versus Atmospheric Circulations in the Lower Vistula Basin (Poland) in 1954–2018

“…in mesoscale), which was proved by Niedźwiedź (1981). This is why this paper relies on atmospheric circulation indices prepared only for the research area (Araźny et al 2021).…”

Bioclimatic features of Toruń according to the tourism climate index

“…Kuchcik et al 2013). The more detailed knowledge of Toruń's bioclimate consists of only two studies by Araźny et al (2015Araźny et al ( , 2016. The first study assesses the spatial diversity of biometeorological conditions in Toruń and its suburbs.…”

“…The paper presents circulation conditions using indices that contain key information on changes in the intensity of zonal and meridional circulation over the study area (Kożuchowski 1993;Kutiel et al 1996;Jacobeit et al 2001;Tomingas 2002;Nowosad 2011;Bartoszek 2017;Araźny et al 2021). This study employs atmospheric circulation indices denoting zonal, east-west circulation (W), meridional, north-south circulation (S) and cyclonicity (C) (Araźny et al 2021).…”

“…The paper presents circulation conditions using indices that contain key information on changes in the intensity of zonal and meridional circulation over the study area (Kożuchowski 1993;Kutiel et al 1996;Jacobeit et al 2001;Tomingas 2002;Nowosad 2011;Bartoszek 2017;Araźny et al 2021). This study employs atmospheric circulation indices denoting zonal, east-west circulation (W), meridional, north-south circulation (S) and cyclonicity (C) (Araźny et al 2021). These circulation indices (W, S and C) were used to study the long-term variability in atmospheric circulation and to assess the impact of atmospheric circulation on selected meteorological, biometeorological and hydrological elements/indexes in Poland (e.g.…”

“…These circulation indices (W, S and C) were used to study the long-term variability in atmospheric circulation and to assess the impact of atmospheric circulation on selected meteorological, biometeorological and hydrological elements/indexes in Poland (e.g. Niedźwiedź 2000;Błażejczyk et al 2003;Falarz 2007;Niedźwiedź et al 2009;Bartoszek 2017;Araźny et al 2021;Barczak et al 2022).…”