The impact of atmospheric circulation on the transport and wet deposition of pollutants in low mountains and foothills of Central Europe
Witold Bochenek, Rafał Kozłowski, Marek Jóźwiak
Air pollutants can be emitted from local, mainly domestic sources, or transported from industrial sites located 100–200 km away. The type of atmospheric circulation and air masses plays a signifcant role in the second case. It is a decisive factor affecting the amount of precipitation and the volume of gases and particulates deposited in a given area. This article provides the frst attempt to compare the pH and conductivity (SEC) results from two monitoring stations within a distance
of 136 km; however, exposed to pollution from different sources. The central aim of the paper is to determine the impact of the type of atmospheric circulation and air masses on precipitation amount, pH and conductivity. The research was conducted in 2004–2009 in the two base stations of the Integrated Monitoring of the Natural Environment network: Święty Krzyż in the central part of the Świętokrzyskie Mountains and Szymbark in the Low Beskid. Regression models based on the
number of particular circulation types and monthly mean pH and SEC values indicate the influence of the frequency of synoptic situations on precipitation physicochemical parameters. In Szymbark there was a positive relationship between the concentration of H+ and south-easterly anticyclonic (SEa), southwesterly anticyclonic (SWa) and southerly cyclonic
(Sc) situations and a negative one with anticyclonic wedge or ridge of high pressure (Ka) and through of low pressure (Bc) situations. The values of the parameter at the Święty Krzyż station were positively affected by westerly anticyclonic (Wa) circulation and negatively by central anticyclone (Ca), as well as Ka and Sc situations. The same circulation type induced
the concentration of H+ in a different manner during winter and summer half-year. Conductivity measured in Szymbark was signifcantly negatively related only to north-easterly anticyclonic (NEc) and Bc circulation types and positively – to northerly anticyclonic (Na) situation. The same parameter showed a strong seasonal variability in Święty Krzyż. It might have resulted
from varying intensity of production processes in the cement plants located in the area of “Białe Zagłębie” (White District) in the SEa and southerly anticyclonic (Sa) synoptic situations, or heightened fuel combustion in winter (easterly cyclonic – Ec circulation). In Szymbark the most distinctive positive relationship was noted between SEC and the arctic air masses (PA),
while a negative one – with maritime polar (PPm) and tropical (PZ) masses. A strong positive correlation was registered between SEC and the frequency of warm maritime polar masses (PPmc) at the Święty Krzyż station, where a negative trend was observed during the prevalence of various air masses (rmp). The analysis of temporal variability and the impact of different types of circulation and air masses on precipitation pH and SEC indicates that there are both congruent as well as contradictory tendencies at the two monitoring stations. Relatively nearby localities are under the influence of different emission sources in terms of direction and distance to the source. Local domestic sources are more important than remote industrial sites situated in Slovakia for the air quality in Szymbark. Physicochemical parameters of precipitation in Święty
Krzyż were affected mainly by the cumulated pollution from Upper Silesia and northern part of the Czech Republic (Ostrava-Karviná Coal Basin).
