Sezony pogodowe w Hornsundzie (SW Spitsberegen) w latach 1980-2003

W pracy przestawiono charakterystykę sezonów pogodowych wydzielonych przy wykorzystaniu metody dendrytu wrocławskiego. Opracowanie wykonano w oparciu o dane opublikowane w rocznikach meteorologicznych wydanych przez IMGW w Gdyni (1980-2000) i Instytut Geofizyki PAN (2000-2003). W Hornsundzie notuje się cztery sezony pogodowe (zima, wiosna, lato i jesień) o zróżnicowanym czasie trwania i o specyficznej strukturze pogód (frekwencja grup, podgrup, klas i typów). Daty ich początków i końców nie pozostają w ściślejszym związku z astronomicznymi porami roku.

Climatic seasons are understood as periods of the time comprising sometimes several months characterized by some definite homogeneity of climatic conditions. Quantity and frequency analysis of types of weather in Hornsund shows that succeeding decades of year are differentiated in a diversified degree. There also exist decades of similar features. The Wroclav dendrite method was applied to distinguish the groups of decades which are characterized by the definite weather homogeneity. If enabled the classification into 4 climatic season according to homogeneity of quantity and frequency of weather types. Each season is characterized by different period of duration and specific weather structure. The distinguished weather seasons are characterized by a right degree of weather conditions contrasts. The most differentiated is the structure of winter weather which indicates that this is the most dynamic period of the weather types appearance. The summer structure is the most homogenous when two weather types comprise on average 30% of time of the season duration. Transitional seasons (spring and autumn) have a similar structure of weather states, the autumn season is colder and less cloudy than the spring season. Both seasons are characterized by the remarkable amount of transitional weathers, frost - thaw types. The distinguished seasons do not belong to thermal or astronomic seasons of the year. The peculiarity of these seasons is their different time of beginning in relation to the sun (solar) energy supplied. Winter and autumn in Hornsund start clearly earlier than their calendar equivalents, spring and summer are delayed.