The impact of weather conditions on hazel pollen concentration in Sosnowiec (Poland) in 1997-2019

Abstract

The goal of this study was to compare hazel pollen seasons in Sosnowiec in 1997–2019 and to analyse the impact of weather conditions on these seasons. The measurements were conducted using a volumetric method with a Burkard spore trap. The duration of pollen seasons was determined using the 98% method. SPI (Seasonal Pollen Index) was calculated as the sum of daily pollen concentrations in a given season. The measurements showed that high temperatures in January and February had an impact on the beginning of the hazel pollen season. They revealed that there are positive correlations with temperatures and sunshine hours long before the season, i.e. 210–180 days before. The daily hazel pollen concentration in Sosnowiec showed a positive and statistically significant correlation with air temperature, sunshine hours, and average and maximum wind speed. Negative correlation was demonstrated for snow cover depth and relative humidity of the air. Daily concentration levels depend also on the type of weather front as well as direction of air mass flow and its type. Variance analysis showed that the highest concentrations of hazel pollen grains were recorded when warm air moves from the south and south– western direction, whereas the lowest ones were noted for air moving from the east, south–east, north and north–east directions. Atmospheric precipitation, snow cover depth, and average, maximum, minimum and near-the-ground temperatures in the season also had an impact on the SPI of hazel pollen grains. High positive correlation coefficients were also observed in the case of thermal conditions, sunshine hours, relative humidity and precipitation from July to September in the year preceding a given pollen season. The duration of the hazel pollen season depends on precipitation, snow cover depth and temperature during a given season.