Cloudiness and cloud genera variability at the turn of the 21st century in Poznań (Poland)

Abstract

The aim of this article was to investigate the effect of macroscale circulation types on total cloud cover in Poznań-Ławica (western Poland) in years 1951–2015. The analysis was preceded by the characteristics of the long-term, annual, and seasonal changes in total cloud cover and cloud genera (data regarding observations of cloud genera covered the period of 1971–2015). The effect of six macroscale circulation types (Arctic oscillation, North Atlantic Oscillation, East Atlantic, East Atlantic/West Russian, Scandinavian, and Polar/Eurasian Types) on the total cloud cover was examined. The amount of cloud cover in Poznań was influenced by the macroscale circulation types, mainly in the warm part of the year. The North Atlantic Oscillation, Arctic Oscillation and Scandinavian types had the strongest impact there.