Porównanie warunków meteorologicznych na zachodnim wybrzeżu Spitsbergenu w sezonie letnim 2005 r.

W artykule przedstawiono porównanie warunków meteorologicznych w sezonie letnim 2005 r. na podstawie danych zebranych w trakcie trwania polskich wypraw polarnych do Hornsundu, Calypsobyen, doliny Ebby i Kaffiöyry. Dodatkowo, aby szczegółowiej poznać ich zróżnicowanie na zachodnim wybrzeżu Spitsbergenu skorzystano z dostępnych danych dla 2 norweskich stacji: Ny Alesund i Svalbard Lufthavn. Ze względu na różny czas pracy polskich ekspedycji polarnych do porównania warunków meteorologicznych wybrano wspólny okres 21.07-31.08. Stwierdzono, iż zróżnicowanie przestrzenne większości badanych elementów meteorologicznych na zachodnim wybrzeżu Spitsbergenu latem 2005 r. było znaczące. Na kształtowanie warunków meteorologicznych na badanym obszarze, a więc i na ich zróżnicowanie przestrzenne, w pełni sezonu letniego większy wpływ wywiera stopień kontynentalizmu klimatu niż szerokość geograficzna. Jednak wraz ze zbliżaniem się końca lata polarnego rola wspomnianych czynników się odwraca.

The paper presents the data concerning the spatial diversification of meteorological conditions occurring on the western coast of Spitsbergen during the summer season of 2005. For the analysis daily data have been used from four Polish stations (Kaffiöyra - KH, Ebby valley - EBB, Calypsobyen - CAL and Hornsund - HOR) and two Norwegian stations (Ny Ĺlesund - NYA, Svalbard Lufthavn - SVA), mainly for the common period of observation (from 21st July to 31st August) (Fig. 1). The Hornsund station was used as a reference station. Differences have been computer for all the analysed meteo-rological variables between stations for every 24-hour period, ten- / eleven-day period, and for the common period of observations as a whole (the meterological variables analysed include air pressure (AP), wind speed (v), cloudiness (C), sunshine duration (SS), maximum daily temperature (Tmax), mean daily temperature (Ti), minimum daily temperature (Tmin), relative humidity (f), and atmospheric precipitation (P)) (Table 1, Fig. 2, Fig. 5). All results proved that the spatial diversification of almost all analysed variables is significant. It is very evident that in the summer the degree of climate continentality has a greater influence on this diversification than the geographical latitude. Local topography plays also important role in the diversification of meteorological variables on the western coast of Spitsbergen. A good example of this influence is presented in Figure 4, showing different kinds of wind roses. It can be seen that winds from different directions dominate in each station. Mean daily courses of some selected meteorological variables (Fig. 3) also show that spatial diversification is varied throughout the day. For example, greater differences are noted during "night" hours for atmospheric pressure and wind speed, while an opposite relation exists for air temperature and relative humidity. Extreme values of analysed meteorological variables during the common period of observation (from 21st July to 31st August 2005) are shown in Table 2. The highest temperature (13.1°C) occurred in Svalbard Lufthavn located in the most continental part of Spitsbergen, while the lowest (0.5°C) was in the Hornsund region, where cyclones bringing thick clouds are very common. Day-to-day variabilities of the majority of the analysed meteorological variables on the west coast of Spitsbergen are quite large (Table 3).