The influence of atmospheric circulation conditions on Betula and Alnus pollen concentrations in Wrocław, Poland

Abstract

The influence of atmospheric circulation conditions on pollen concentrations of two taxons (Betula and Alnus) in Wroclaw, Poland, for the years 2005-2014 was analysed. Pollen concentration was analysed separately for twenty circulation types that were determined using objective classification. The results indicate the atmospheric circulation conditions favourable for both low and high pollen concentrations over Central Europe. Pollen concentrations vary significantly according to circulation types. The highest pollen concentrations for both taxons are typical for warm, sunny, and dry anticyclonic circulation types with anticyclone in the lower and upper troposphere, especially for types with advection from the SW. The lowest pollen concentrations are observed for cold, wet, and cloudy cyclonic types with advection from the northern sectors. There is also a positive and statistically significant trend in the frequency of circulation types favourable for high concentrations of Betula and Alnus.

Multi-Annual Changes in Heat Stress Occurrence and Its Circulation Conditions in the Polish–Saxon Border Region

“…In terms of evaluation of the results from the circulation perspective, the classification of atmospheric circulation developed by H. Ojrzyńska [66][67][68] was used. This classification was carried out for the region of the Sudety Mountains and their surroundings, including southwest Poland, southeast Germany, and east Czechia.…”

“…Using the spline function, the data were interpolated to a spatial resolution of 5 km × 5 km. To determine the circulation type for each day, a prevailing type was calculated by applying the mode function for all the 5 km × 5 km grid cells [67]. The direction of advection was evaluated based on the wind direction from the 700 hPa isobaric level for a wind speed higher than 2 m/s.…”

The course of birch pollen seasons in Sosnowiec (Southern Poland) in 1997–2020 in relation to meteorological conditions

“…Grundstro ¨m et al (2017) concluded that the approach based on types of weather is a relatively easy method for characterizing weather conditions on a synoptic scale; it groups many meteorological variables relevant to the processes deciding on high or low concentration levels of pollen. Studies conducted in Go ¨teborg and Malmo ¨showed that high concentrations of birch pollen were correlated with dry and moderately calm conditions during an anti-cyclone and types of weather with geostrophic NE, SE, and S winds, and the lowest concentration levels were found in humid and windy conditions with wind directions SW, W, and NW, as well as for a cyclonic type (Grundstro ¨m et al, 2017). Ojrzyn ´ska et al (2020 noted that the highest pollen concentration for both alder and birch in Wrocław (Poland) is observed during warm, sunny, and dry anti-cyclonic circulations an anti-cyclone in the lower and upper troposphere, especially for the types with advection from the SW direction.…”

Evaluation of Tourism-Climate Conditions in the Region of Kłodzko Land (Poland)

“…The results of the analysis on CTIS were presented as a calendar of weather conditions for particular 10-day periods. In order to present the most intensive heat-stress conditions and their relation to the atmospheric circulation, a calendar of circulation types developed by H. Ojrzyńska was used [85][86][87]. This classification concerns the Sudetes Mountains and the surrounding regions, and is based on the data related to vorticity (C, cyclonic; A, anticyclonic) and the direction of advection: NE, northeast (1-90 • ); SE, southeast (91-180 • ); SW, southwest (181-270 • ); NW, northwest (271-360 • ); and XX, indeterminate direction.…”

“…These data were interpolated to a spatial resolution of 5 km × 5 km using the spline function. Circulation types for particular days were assessed based on the prevailing type, which was calculated by applying the mode function for all the 5 km × 5 km grid cells [86]. The types of vorticity were evaluated using geopotential values from the 850 hPa isobaric level.…”