The influence of atmospheric circulation on the spatial diversity of air temperature in the area of Forlandsundet (NW Spitsbergen) during 2010–2013

Abstract

ABSTRACTThe relationship between atmospheric circulation and climate in Svalbard has been described in dozens of studies. However, the data used for that purpose usually came from permanent stations on the coast. The influence of atmospheric circulation on topoclimatic diversity has not been explored so often, and hardly at all for other periods than the Arctic summer. In this article, the relationships between circulation and air temperature are described using daily data sourced from six sites located around Forlandsundet (NW Spitsbergen) during 2010–2013. The analysis was conducted independently for three seasons identified as: winter (Nov–Mar), spring/autumn (Apr–May and Sep–Oct) and summer (Jun–Aug) and also for three air temperature parameters: diurnal mean (Ti), maximum (Tmax) and minimum (Tmin) temperature. The atmospheric circulation in the studied area was described using Tadeusz Niedźwiedź's classification of diurnal circulation types for Svalbard. The influence of atmospheric circulation on the spatial pattern of air temperature is not uniform across the Forlandsundet region; in particular, important differences were observed between coastal and inland parts of the study area. Thus, generalization of relationships between air temperature and atmospheric circulation for the entire area of Spitsbergen based on data only from coastal stations is not appropriate. The influence of atmospheric circulation on the spatial pattern of air temperature in the Forlandsundet region also changes through the year. In the cold season (Sep–May) it differs significantly from that observed in summer (Jun–Aug), and this feature is also seen in analyses of the 10% highest (≥ 90th percentile) and lowest (≤ 10th percentile) thermal differences. In summer, the influence of atmospheric circulation on air temperature in the topoclimatic scale is definitely less stable than in the cold season.