Celem pracy jest charakterystyka warunków meteorologicznych w Falentach w latach 1981-2001 na tle wielolecia. W okresie wegetacyjnym o prawidłowym rozwoju roślin decydują optymalne temperatury oraz opady zapewniające odpowiednią wilgotność gleby. Na rozwój roślin ma również wpływ przebieg warunków meteorologicznych w okresach poza wegetacją. W okresie badań występowały lata, a także kilkuletnie okresy z opadami znacznie odbiegającymi od średnich z wielolecia. Najmniejsze opady odnotowano w latach 1986-1993, a najbardziej niekorzystny dla rozwoju roślin był rok 1992, z sumą opadów 439,4 mm, z czego na okres wegetacyjny przypadło tylko 213,9 mm. Średnie temperatury powietrza do 1987 r. nie odbiegały znacznie od średniej z wielolecia, a ich wyraźny wzrost odnotowano w latach 1988-1994 (okres ten pokrywa się więc częściowo z okresem niskich opadów). Okres wegetacyjny o najwyższej średniej temperaturze wystąpił w 1992 r. Wyniosła ona 16,8°C, a więc aż o ponad 2°C więcej niż średnia temperatura okresu wegetacyjnego z wielolecia; w roku tym odnotowano też najwyższą w wieloleciu temperaturę powietrza 36,5°C.
EN
The aim of this work was to characterise changes of meteorological conditions in Falenty in the years 1981 - 2002 against long term meteorological records. Optimum temperatures and precipitation in the growing period guarantee appropriate soil humidity and determine proper growth of plants. The latter may be also affected by weather conditions outside the growing season. There were years during the studied period with precipitation considerably deviating from the long term average. The lowest precipitations were observed in 1986-1993 and the most disadvantageous for plant growth was the year 1992 with annual precipitation of 439.4 mm and only 213.9 mm in the growing season. Average air temperatures up to the year 1987 did not significantly differ from the long term average, their distinct increase was noted in 1988-1994 (in part accompanied by low precipitation). The highest average temperature during the vegetation season was noted in 1992 and amounted 16.8°C, so by 2°C higher than the long term average. In this year the highest air temperature (36.5°C) of a long term period was recorded.
W przypadku wentylacji średnie dobowe ( miesięczne ) temperatury powietrza można zastosować tylko do przypadków, w których wentylacja jest czynna w sposób ciągły w czasie doby i o stałej wartości objętościowego strumienia powietrza. W większości obiektów zamieszkania zbiorowego i użyteczności publicznej, wentylacja lub klimatyzacja wykorzystywana jest w okresie krótszym od doby, stąd też pojawia się istotny problem ustalenia średnich miesięcznych temperatur powietrza zewnętrznego dla czasookresu, w którym działają urządzenia wentylacyjne w budynku. W artykule podjęto próbę rozwiązania tego problemu.
EN
The day-averaged and monthly-averaged mean air temperatures may be applicable lor cases ot ventilation systems permanently operated and systems of the constant air flow. However, in most cases ol ventilation and air-conditioning systems for large multi-family buildings and public buildings operation time ot these systems is shorter than twenty-four hours. Theretore the establishing otthe monthly-averaged outside air temperatures tor operating period of these systems may be treated as a crucial problem. The attempt at solving this problem has been presented in the paper.
W artykule omówiono różne metody obliczania średnich dobowych temperatury powietrza w Arktyce Amerykańskiej w XIX wieku. Oceniono dokładność stosowania tych metod biorąc pod uwagę jako średnią wzorcową tzw. średnią dobową rzeczywistą temperaturę powietrza obliczaną z 24 danych cogodzinnych. Drugim problemem badawczych, który podjęto w artykule, jest oszacowanie wielkości błędów jakie się popełnia wybierając z różnych zbiorów danych godzinowych (co 1-, 2-, 3-godziny itd.) najwyższe i najniższe dobowe temperatury powietrza. Jako wzorzec w tym przypadku wykorzystano wartości temperatur maksymalnych i minimalnych powietrza odczytane z termometrów ekstremalnych. Podobną analizę przeprowadzono także dla amplitudy dobowej temperatury powietrza. Dla wszystkich analizowanych parametrów termicznych i dla wszystkich metod obliczania/wyznaczania średnich dobowych temperatury powietrza i temperatur ekstremalnych obliczono m. in. przeciętne błędy estymacji ich średnich miesięcznych wartości.
EN
Knowledge about the history of climate in the Arctic is more and more important and necessary, especially at present when we are approaching the Fourth International Polar Year 2007-2008. Generally speaking, the history of the climate in this area during the 20th century is quite well known. On the other hand, little is known about the climate in the 19th century. Moreover, while we have extensive meteorological data for this period, in particular for the American Arctic, these data have many errors and biases. One of the most important biases is connected with the way in which daily mean air temperature has been calcu-lated. In the American Arctic during the 19th century nine different methods (m1-m9) were used. For the analysis we also added two presently used methods (m10-m11). The main aim of this paper is to estimate the magnitudes of errors which are connected with the use of the above methods of calculating daily means. As a real daily mean, the mean calculated using hourly data (m1) was used. Because in the American Arctic the mean daily air temperature is still calculated using formulae m11, we also calculated differences relative to this mean. Another issue which we undertake in the present paper concerns the estimation of errors which are the result of the method which was adopted to determine extreme temperatures (Tmax and Tmin) and the diurnal temperature range (DTR). We checked this for ten different methods (nine used in the 19th century) which used hourly, 2-, 3-, and 4-hourly etc. readings of air temperature for the purposes of calculation (see formulas m1-m10 for more details). As a base, real data, temperature readings from the extreme thermometers were used. For the analysis, hourly temperature data as well as daily Tmax and Tmin for the period 1979-1983 were used for the four meteorological stations (Eureka, Resolute, Coral Harbour and Iqaluit) located in the American Arctic. The results of our investigations are presented in Tables 1-5. The main conclusions can be summarized as follows: 1. Mean monthly temperatures obtained using methods m2-m5 and m9 of daily mean temperature calculation do not need to be corrected. The greatest errors (overestimation by 0.5 to 1.5°C) were found for the methods m6-m8 (owing to a lack of measurements during the night hours). The method m11 also produces significant errors. Generally, using this method, the mean monthly temperatures are most often lower (by 0.2 to 0.7°C) in relation to all methods analysed in the present paper (see Tables 1 and 2). 2. In accordance with expectations, mean monthly Tmax and Tmin determined using different methods are lower/higher than the respective monthly means calculated based on the readings from the maximum and minimum thermometers. When we determine Tmax and Tmin using hourly, 2-, and 3-hourly data, their monthly means are lower/higher, though generally by no more than 1.0°C. Greater errors are more clearly seen in the cold half-year than in the warm half-year (see Tables 3 and 4), 3. Mean monthly DTR calculated using hourly, 2-, and 3-hourly temperature data are lower than real values by about 0.5 to 2.0°C. For other methods of DTR calculations their errors are significantly greater - lower by about 3.0 to 4.0°C (see Table 5).
This work has analysed changeability in water surface temperature in sea areas in the direct vicinity of West Spitsbergen. (Fig. 1). The analysis made use of SST (Sea Surface Temperature) from Reynolds?s data, covering mean monthly values of grids 1 x 1° from the period 1982-2002 (21 years). The changes in SST have been examined both monthly and yearly in 48 grids originating from the region 76-80°N, 006-020°E. A noticeable increase in water temperature was noted in the entire analysed area. The highest positive annual trends in water temperature were noted in the region 77-78°N, 006-007°E located west of Spitsbergen. In this area the mean yearly trends in SST values exceed +0.11°C/year and are highly statistically relevant (p<0.001). The values of trend noted in the areas in the direct vicinity of SW coast of Spitsbergen are +0.07°C to +0.08°C/year (at the latitudes 76-78°N). Farther north the values of the trend are remarkably lower, yet they are still highly statistically relevant. At 80°N the SST trend ranges from +0.006°C to +0.013°C and grows when moving west. At 79°N the observed trend of mean yearly value of SST is within the range from +0.04°C (010°E) to +0.07°C/year (006°E). This indicates that the mean yearly temperature of water in the region west of Spitsbergen has increased by more than 2.5°C over the period of the last 21 years and in coastal waters SW of Spitsbergen by about 1.5°C to 1.7°C. The lowest increase in SST was noted in waters at 80°N, where it did not exceed 0.3°C within 21 years. The increase in water temperature is distributed unevenly in time - since 1995 the rate of the increase has been rapidly growing (see Fig. 2). The changes in yearly SST values, as the analysis indicated, are influenced by the changes in temperature noted mainly in the period from September to February. This proves that the heat sources carried by the West Spitsbergen Current are increasing and that the summer warming of waters is becoming more and more significant. Interannual changeability in SST in the remaining months proves to be relatively low, in extreme cases being zero (water completely frozen). It can be observed especially at 80°N. The yearly changeability in values of SST in waters around SE coasts of Spitsbergen (Storfjorden) is mainly influenced by the temperature of waters in autumn (August ? October), which means that the influence of the summer warming of waters on the yearly SST value in this area has increased.
Characteristic feature of the air temperature course over the year on the Antarctic is the winter warming known as a Coreless Winter effect (Hann 1909, Marsz 2000). This phenomenon is related to the specific atmospheric circulation, frequent advection of warm air masses from the oceans into the interior of the continent and entering of cyclones onto the Antarctic. The rise in temperature during the winter season occurred in the period 1990-1999 on all selected researched stations, however it didn't become visible every year (Table 2). Analysis of annual courses of air temperature in the particular years in the last decade of 20th century proved, that the occurrence of the Coreless Winters on the Antarctic is a repeated phenomenon, characterized by spatial and temporal variability. An example of annual courses of air temperature with the coreless effect in 1997 on selected stations is shown on Fig. 2. The least number of Antarctic stations with the winter warming were observed in 1992, when the phenomenon was merely recorded on the half of all selected stations (Fig. 3), whereas the greatest extent was stated in 1997, when it occurred on the 88% of all the stations. Extents in the occurrence of the kernlose winters on the Antarctic for the particular years during the decade 1990-1999 are shown on Fig.4. In respect of regional location there was stated the existence of interdependences in the periods in occurrence of the rises in temperature during the winter season within 4 typical regions of the Antarctic according to selected research stations: - on the Antarctic Peninsular - in the interior of the continent - on the coast in zone 030°W - 120°E - on the coast in zone 120°E -120°W The analysis of annual courses of air temperature in the years with coreless effect indicated, that the most often rise in air temperature in the winter season was observed on the stations on the coast in zone 120°E - 120°W of the Antarctic, whereas the most rarely it was noted on the Antarctic Peninsular. The rises in temperature were mostly observed on the whole continent in June which equals 45% of all the warmings noted in years 1990-1999 on every stations, and in July - 33%. The rises in temperature were the most rarely observed in August and occurred merely in 22% of all the warmings. The relative frequency [in %] of occurrence the rises in temperature in the winter season according to month's intervals for the particular regions of the Antarctic in the period 1990-1999 is shown on Fig. 5. The great spatial and temporal variability in occurrence of the Coreless Winters on the Antarctic observed during the last decade of 20th century may prove the existence of the considerable dynamics of the circulation factors, which determine the formation of this phenomenon.
Kruszewski, Marsz and Zblewski (2003) found out that winter temperature of water in the Norwegian Current indicates quite strong, occurring with a delay, correlations with the air temperature at Spitsbergen, Bjornoya, Hopen and Jan Mayen. Strong and statistically significant correlations between the mean sea surface temperature (SST) in the period January-March in grid 2°x2° [67°N, 10°E] and the monthly temperature of July, August and September with SST are marked the same year (3-5 month delay) and with the air temperature in November and December the following year (18-20 month delay). Waters of the Norwegian Current transport warm, of higher salinity Atlantic waters. Winter SST of the Atlantic Ocean characterizes the heat resources in the deeper layers of waters. SST in grid [67,10] in an indirect way characterizes heat resources carried with the Atlantic waters into the Norwegian Sea and farther to the Arctic together with the West Spitsbergen and Nordcap currents. The aim of this work is to describe the influence caused by changes in heat resources transported to the Arctic with the Norwegian Current on the annual temperature of air in the region of Hopen, Spitsbergen and Jan Mayen. The examined period covers the years of 1982?2002 and is marked by great warming in this area. The analysis of spatial distribution of correlation coefficients justifies Kruszewski and others (2003) hypothesis of mechanism causing the delayed influence of changes in water heat resources on the air temperature in this region The observed positive correlations between winter SST in [67,10] grid and air temperature in July, August and September result in the influence of changing water heat resources on atmospheric circulation noted in these months. Positive correlations in November and December in the following year result from the ?onflow? to the Arctic of warmer and of high salinity Atlantic waters. They have influence on the ice formation on the Greenland and Barents seas thus causing that influence of changing heat resources carried with waters on air temperature is much stronger. The analysis of regression made it possible to establish the correlation between annual air temperature at a given station (Ts) and winter water temperature (Tw) in [67,10] grid. Annual temperature in a year k is a function of two variables: Tw of the same year as the temperature Ts (Tw(k)) and Tw from the preceding year (Tw(k-1)): Ts(k) = A + b . Tw(k) + c . Tw(k-1) Table 3 contains the values of constant term and regression coefficients as well as statistical characteristics of formulas for the analysed stations. Both variables Tw from the year k and the year k-1 explain about 40% of the changeability in mean annual air temperature of the observed 20-year period at the analysed stations. This means that only one element, i.e. heat resource in the waters of the Norwegian Current, defined with the value Tw, determines more than 1/3 of the whole annual changeability in air temperature in the region located from Jan Mayen up to Hopen and from Tromso up to Ny Alesund. The station for which maximum explanation may be applied (47.7%) is Hopen, the station where the positive trend in annual temperature is the highest (+0.090°C/year). The values of regression coefficients b and c prove that the inertial factor connected with advection of the Atlantic waters has greater role in the changeability in mean annual temperature of air. The analysis of formula [2] indicates that great increases and decreases in annual temperature at the discussed stations will be observed in a k year if the values of Tw in two following years are significantly higher or lower than the mean ones. That is why the occurrence of positive trend in value of Tw should be followed by relatively systematic increase in annual air temperature at stations located at the described region. A positive trend in annual air temperature was noted at the analysed stations over the period 1982?2002. At Jan Mayen its value is +0.067 (ą0.028)°C/year (p<0.026). When taking the estimated values of regression coefficients in the multiple regression connecting the annual temperature at Jan Mayen with the value of Tw (Table 1) and the same value of trend T equal to +0.023 then the value of annual trend in air temperature at Jan Mayen influenced by trend Tw equals 0.0598°C/year. The obtained result indicates that the whole or almost whole warming observed at Jan Mayen in the years 1983-2002 may be explained by direct and indirect influence of the increase in the value of Tw over that period.
The paper describes weather conditions (based on air temperature and humidity) in Treurenberg Bay and Massif Olimp (NE Spitsbergen) for the period from 1st August 1899 to 15th August 1900. The hourly data of the meteorological elements under analysis were collected by the Swedish-Russian scientific expedition, which was sent to Spitsbergen in 1899 to measure an arc of the Earth?s meridian. During the expedition two meteorological stations were established (Fig. 1): the main one (21.9 m a.s.l.) located by the sea in Treurenberg Bay (hereafter 'Treurenberg') and a secondary station (408 m a.s.l.) situated on Massif Olimp (hereafter 'Olimp'). The quality of data were checked and assessed as being very good, especially for the Treurenberg station. The air temperature (T) in Treurenberg in the annual march was highest in August (mean monthly T = 2.1°C) and lowest in March (-27.0°C) (Tab. 2, Fig. 2). Mean yearly T was equal to -9.8°C. The values of T in this part of Spitsbergen are significantly lower than in the western coastal part of the island where, for example, the average annual T for the period 1975-2000 was about twice as high (see Przybylak et al. 2004). On the other hand, mean monthly daily T ranges in Treurenberg are greater (Fig. 3). Day-to-day T changes in the annual cycle were greatest in the cold half-year, and lowest in summer (Fig. 4). These changes are lower here than in the western coastal part of Spitsbergen. Mean monthly daily courses of T are clearest from April to September, showing maximum T in the afternoon, and minimum in the early morning hours (Fig. 5). From October to March (but especially during the polar night) the average daily courses were smooth. Air humidity in Treurenberg was characterized using three commonly used variables: water vapor pressure, relative humidity, and saturation deficit. Due to very low T and quite a large thermic continentality of the climate in NE Spitsbergen, water vapor pressure in Treurenberg is lower than in the western coastal part of Spitsbergen. The highest values in Treurenberg occurred in summer (on average about 6 hPa) and the lowest in late winter (below 1 hPa) (Tab. 2, Fig. 6). Generally, similar relations in the annual march are also seen for two other air humidity variables (see Tab. 2, Fig. 6). The annual cycles of day-to-day changes of all humidity variables in Treurenberg are not clear, as they consist of many maximums and minimums (Fig. 7). These changes are lower here than in other parts of Spitsbergen (see Table 15 in Przybylak 1992a). Mean daily courses of relative humidity are smooth for most months. Only in April and in the period from June to September do we see normal daily cycles with lowest values in 'day' hours and highest values in 'night' hours (Fig. 9). The annual course of T in the Olimp station is similar to that occurring in Treurenberg (Figs. 2 and 10). Of course, the upper station was colder, but only by 1oC for mean annual values (Fig. 11). The drop of T in the Treurenberg region - a drop that is lower than is normally observed in the atmosphere (0.6oC/100 m) - was probably caused by measurement errors (the thermograph at the Olimp station was wrapped in thin material in order to stop the snow accumulating around the metallic sensor). Only limited air humidity data were gathered for the Olimp station due to measurement problems of this element in cold half-year. Therefore, most observations were made only in summer, and they show that the relative humidity was in most cases greater here than at the Treurenberg station. The investigation shows that weather conditions in the NE part of Spitsbergen differ significantly from those observed in the western coastal part of the island. Both T and air humidity are significantly lower in the study area, and these differences in the case of T are especially large in winter.
The study presents variability of simple circulation indices above Spitsbergen for the period 1899-2004 in January, based on original calendar of synoptic divided from the synoptic maps. After calculation of synoptic types frequencies the further results have been obtained using the simple circulation indices: W - westerly, zonal index, S - southerly - meridional index, C - cyclonicity index, as proposed by R. Murray and R. Lewis (1966) with some modifications, as well as Spitsbergen Oscillation (OS) defined as the standarized pressure difference between Bjornoya and Longyearbyen. The negative value of W index is typical for Spitsbergen, according to great frequency of eastern airflow. Variability of January temperature in Svalbard (t01SV) were investigated on the basis of averages from four stations: Isfjord Radio and Svalbard Lufthavn, as well as from Polish Polar Station in Hornsund Fiord on SW part of Spitsbergen, and from Bjornoya (Bear Island) - about 300 km SSE from Hornsund. After reconstructions of some lack data on the basis of linear regression, temperature data were obtained for the period of 1912-2004. For the temperature the main feature is period of cooling in the years 1912-1918 and then the great warming during the decade of 1930th (1933-1937). During the years 1937-1971 was observed the significant decreasing trend in January temperature to the cool period of years 1962-1971. The last period 1971-2004 has no any trend in temperature. But three large fluctuations took place with warm Januarys of 1972-1974, 1990-1992 and 1999-2001 and cool ones of 1975-1982, 1993-1998 and 2002-2004. Temperature of January changes in Spitsbergen depend on a great extend of circulation factors, mainly from the southern (S) and zonal circulation indices (W) or Spitsbergen Oscillation index (SO). Using the models of multiple regression was possible the recontruction of January temperature since 1899 on the basis of circulation indices. They explained about 63% of variance in temperature.
Evaluation of thermal conditions on polar station is the subject of this paper. Calculations based on the Polish Polar Station in Hornsund data at 06, 12 and 18 GMT in the period 1991-2000. Three bio-meteorological indices were analyzed: Wind Chill Index (WCI) according to Siple-Passel formula (1945), Wind Chill Temperature Index (WCTI) based on new American and Canadian formula (2002) and Insulation Predicted (Iclp) according to Burton-Edholm formula (1955). Hypothermic conditions were noticed most often (60-90%) during considered period. Comfortable thermal conditions took below 10% causes per month only. The risk of frostbite of exposed skin could be noticed from November to April from 1% to over 18% causes per moth. The most severe conditions were occurred in February. There is a necessary to use clothes of over 4 clo thermal insulation and wind-protectors for most of considered period. There is also the need for keeping active, covering exposed skin and being ready to short outdoor activities.
The Weather calendar for the Founding Expedition Hornsund 1957/58 is conceived using four meteorological elements: air temperature, wind speed, precipitation and relative humidity. Each of those variables is classified as system consisting of three classes, except precipitation, which comprises two classes. First class contains values below 25% percentile (under normal), third contains values above 75% percentile (above normal) of meteorological elements under consideration. Second class contains values between first and third class (normal). Precipitation is classified using two-class system, which describes if precipitation occurs or not. These rules give 3 groups, 9 subgroups, 18 classes and 54 types of weather. All statistics are presented for three periods: 12 months from August 1957 to July 1958, polar night and polar day. In all these periods groups of weather with normal temperature (2WOF) dominate. Typical weather subgroups are those of low temperature and weak wind (11OF) as well as normal temperature with weak (21OF) and moderate wind (22OF). Prevailing weather class is cool weather with weak wind and without precipitation (110F). Characteristic attribute of Hornsund area is weather with low humidity (TWO1).
Diurnal air temperature ranges (DTR) have been counted based on the monthly mean values of the daily maximal and minimal air temperature from 23 Antarctic stations. DTR shows a considerable spatial differentiation on the Antarctic. The lowest DTR values (4-6°C) occur along the western coast of the Antarctic Peninsula and on the subantarctic islands. At the remaining coast of Antarctica the mean DTR vary from 6-7°C to 10°C at the stations situated on higher geographical latitude. In the Antarctic inlands the largest DTR values occur at the highest parts of glacier plateau (8-9°C), while on the South Pole they are distinctly smaller (6°C). In the annual course of DTR the following types have been distinguished: oceanic type at the western coast of the Antarctic Peninsula with small DTR in summer (2-4°C) and twice higher in winter; oceanic-continental type at the coast of Eastern Antarctic with large DTR during the whole year; continental-oceanic type with high DTR in summer and still higher (up to 13°C) in winter occurring at Western Antarctic and in the Weddell Sea basin; continental type characteristic for the interior of the continent with the highest DTR in summer (11-12°C) and smaller in winter; polar type with small DTR in summer (to 3°C) and considerable higher in winter (7-8°C). A decrease of DTR occurred on the Antarctic in regions characterized by increasing temperature in the second half of the 20th century, especially on the western coast of the Antarctic Peninsula, on the coast of Ross Sea and on the Queen Maud Land. The decrease in the DTR values was connected with the quicker increase of daily minimal air temperatures. On the other hand, in the regions where cooling was noted the DTR values increase (inlands of Eastern Antarctic and South Pole, and the Weddell Sea basin), mainly due to the fall in daily minimal air temperatures.
This work attempts to determine connections between glaciers' winter mass balance and meteorological factors of winter seasons. Detailed analysis was carried out between the snow accumulation of Austre Broggerbreen and the meteorological data from Ny-Alesund station (Kongsfjord region) from 1975 to 1998. Relation has been found between the snow accumulation and warm and humid air masses frequency in winter seasons (X - V). Those masses are mainly from southerly and southwesterly directions for Svalbard. The winter mass balance shows very clear connection with air temperature and precipitation factors of winter seasons (sum of winter precipitation, number of days with precipitation intensity >= 5 mm per day, winter mean air temperature, and number of days with maximum daily air temperature >= 0°C). A particularly close connection is observed between winter mass balance and number of days with precipitation intensity >= 5 mm per day at the positive daily maximum air temperature (LPTmax) (r = 0.81) - Fig. 8. The winter mass balance multiply regression (Wb) was worked with the use of the elementary meteorological factors: the average winter temperature (T) and the sum of precipitation in the same period (P). On the basis of the multiply regression of winter balance it is possible to predict snow accumulation changes. Over the next 50 years the winter snow accumulation of Austre Broggerbreen could increase about 15% if the scenario of climatic changes by Hanssen-Bauer (2002b) is used. If, in addition, one assumes the stability of ablation, the mass balance of glaciers will rise by 24%, but the mass balance will still be negative.
The progressive increase in the concentration of greenhouse gases in the atmosphere in consequence leads to the rise of the global air temperature. According to the III Report of IPCC (2001) from 1880 the mean temperature on the Earth has grown by 0.6°C ą0.2°C. The reaction of polar regions to the greenhouse effect is unknown. The Antarctic climate shows a considerably greater variability in comparison with the lower latitudes of the Southern Hemisphere. This is conditioned by interactions between the atmospheric circulation, the ocean, and the cryosphere. According to the scenarios of global greenhouse effect the temperature at the polar regions should grow by 3°C in summer and 4-5°C in winter. However, these model researches are not confirmed in reality. This shows that our knowledge concerning the functioning of climate system of the polar regions is insufficient. In the paper we have used monthly mean air temperature values for 21 stations being in operation on the Antarctic in the years 1958-2000 and for 34 stations making observations in the years 1981-2000. After checking the homogeneity of the series by the Alexandersson?s (1986) test we have counted the trends of air temperature. The average trend for annual and seasonal values were expressed by temperature change per 10 years. In the years 1958-2000 on the Antarctic the trend of the mean annual values of the air temperature shows great spatial differentiation. These differences are connected with the radiation balance depending on the variability of cloudiness and the albedo of the surface, and on the transformation of pressure fields and changes of the atmospheric circulation. Statistically significant (on 0.95 significance level) air temperature increase occurred on the western coast of the Antarctic Peninsula (for example Faraday 0.67°C/10 years) and at the stations Belgrano and McMurdo. A negative air temperature trend occurred on the South Pole (-0.21°C/10 years) and on the Droning Maud Land. The temperature changes in the region of the Antarctic Peninsula are correlated with the extension and surface of sea ice, especially in winter. There are considerable differences of air temperature trends on the Antarctic between the periods 1958-1980 and 1981-2000. The period 1958-1980 is characterized by an increase of air temperature, especially on the shore of continent (Casey 0.84°C/10 years, Faraday 0.76°C/10 years, Halley 0.69°C/10 years). The interior of the continent is distinguished by stability of weather conditions. Year-to-year temperature changes are smaller, then at the coast (the trend at the Amundsen-Scott station average 0.26°C/10 years). During the last years (1981-2000) significant changes took place in the tendency of air temperature on the Antarctic. In many regions of the Antarctic cooling began, on the cost of East Antarctica the temperature decreases, on the coasts of the Wilkes Land (Casey -0.82°C/10 years) and the Weddell Sea (Halley -1.13?C/10 years, Larsen Ice -0.89°C/10 years), especially in the autumn-winter period. In the interior of the continent also lower and lower temperatures occurred (Amundsen-Scott -0.42°C/10 years, Dome C -0.71°C/10 years). The cooling can be observed in all seasons, but it is the greatest in summer and autumn, when the decrease of solar radiation was observed in connection with the growing cloudiness. Vostok situated at the highest parts of ice dome does not show statistically significant trend. An increase of the temperature was observed in the interior of West Antarctica (Byrd 0.37°C/10 years). The warming rate of the climate became weaker on the Antarctic Peninsula (Faraday 0.56°C/10 years). The largest temperature changes occurred in the autumn-winter season when in the Antarctic Peninsula region the temperature increased, while in the interior and at the coast of East Antarctica considerably fell. Climate changes during the last 20 years of the 20th century showed the weakening of the warming rate on the Antarctic Peninsula and distinct cooling on the East Antarctica. The lack of warming, or even cooling, on the East Antarctica, is favourable to maintain the present climate system in this region. The increasing air temperature on the West Antarctic, especially on the Antarctic Peninsula caused many natural consequences. The ablation of glaciers clearly intensified, deglaciation takes place, glaciers retreat. The environmental changes lead to disturbances in the functioning of the Antarctic ecosystem.
The study presents variability of simple circulation indices above Spitsbergen for the period 1951-2002, based on original calendar of synoptic divided from the synoptic maps. After calculation of synoptic types frequencies the further results have been obtained using the simple circulation indices: W - westerly, zonal index, S - southerly - meridional index, C - cyclonicity index, as proposed by R. Murray and R. Lewis (1966) with some modifications. The negative value of W index is typical for Spitsbergen, according to great frequency of eastern airflow. Some complicated relations between above indices, NAO, temperature and precipitation were noticed in Spitsbergen. Variability of temperature and precipitation based on the data from Isfjord Radio and Svalbard Lufthavn stations, as well as from Polish Polar Station in Hornsund Fiord on SW part of Spitsbergen. They were compared with Bjornoya (Bear Island) - about 300 km SSE from Hornsund. For the temperature the main feature is period of cooling in the years 1961-1971 and around 1988, after the great warming during the decade of 1930th. During that coolest years also large annual temperature range was typical. The coldest was year 1968, and the warmest one -1984 (from -2 to -3°C). Next warm years were observed in 1990 and 1999, but in Jan Mayen the warmest was year 2002. The coolest winter (December-February) with average temperature below -20°C in Longyearbyen was in 1962/1963 (-21.5°C) and 1988/1989 (-20.1°C), and the warmest one on 1984/1985 (-8.3°C). Significant warming was noticed only in the warm half-year (V-X) about 1.2K since 1972 up to 2002. The warmest period V-X was in 1990, and coolest - in 1968. In summer (June-August) the temperature varied between 2°C in 1982 and 4.5°C (Hornsund) or 6.1°C (Longyearbyen) in 2002 (the warmest summer). Temperature changes in Spitsbergen depend on a great extend of circulation factors, mainly from the southern (S) and zonal circulation indices (W). The lowest temperatures were observed round the 1965. During the last decade of 1980 the period of little warming is observed again. For precipitation relative large increase of summer and September precipitation were noticed in the last years of the 20th century, mainly in 1994-1997. May be the part of its fallen in the form of snow in the upper parts of archipelago and supplied glaciers. The highest precipitation is typical for August and September. The largest diurnal precipitation totals - 58.3 mm was observed on August 1, 1994. The second high value 52.6 mm was noticed on September 6, 1996. During the observed period since 1978, only 5 time the daily precipitation in Hornsund exceeded 40 mm and 14 time were higher than 30 mm. In Hornsund annual total of precipitation twice exceeded 600 mm, in 1994 and 1996. This increase of precipitation was connected with greater frequency in the intensity of westerly and southerly atmospheric circulation expressed by the zonal and meridional circulation indices and the more intense cyclonic activity in autumn and winter seasons
This work deals with correlations between SST in the Norwegian Sea and air temperature at selected stations located in the Atlantic sector of Arctic (Bjornoya, Hornsund, Svalbard-Lufthavn, Ny Alesund and Jan Mayen). The southern and central parts of the Norwegian Sea show the strongest correlation with the air temperature at the above mentioned stations, whereas the northern parts of this sea show weaker correlation. Apart from synchronic correlations (occurring in the same months) asynchronic correlations have been found. The latter are generally much stronger than the synchronic ones. The predominant influence on the changes in air temperature at the stations have the winter SST (JFMA) in the central part of the Norwegian Sea (grid 2° x 2°, 67°N, 010°E). These winter SST show quite strong correlations with monthly air temperature at Bjornoya, Hornsund, Svalbard-Lufthavn and Jan Mayen in July, August and September. At Ny Alesund station the period with statistically significant correlation between the air temperature and the winter SST is limited to September. The strongest correlation can be observed in August (see Table 4). The observed correlations result from modification in atmospheric circulation, caused by increased heat volume in the Norwegian Sea. Such modification is reflected in the increased frequency of occurrence of meridional atmospheric circulation, which is accompanied by the increase in the frequency of air advection from the S to this sector of Arctica. Some correlations which show more significant time shift have also been observed (see Table 5). Winter SST indicate positive correlations with air temperature observed at Bjornoya and Horn-sund in August and September the following year and at Svalbard-Lufthavn in September. At Ny Alesund station the coefficients of correlation with the air temperature in the following year are increased but they do not reach the statistically significant level. Another period with statistically significant correlations is November and December the following year; significant correlations with winter SST occur at Bjornoya (r = 0.71) and all stations located on Spitsbergen (r = 0.57). The correlations of SST with air temperature observed at Jan Mayen the following year are different, i.e. the presence of strong correlations is limited to summer season - July, August and September (r ~ 0.6). The correlations with winter SST occurring in November and December the following year is connected with warm masses carried to this region together with waters with the West Spitsbergen Current. Correlations between SST and air temperature present in summer and at the end of summer the following year may probably be influenced by the modification of atmospheric circulation. The only significant correlation with summer (July and August) SST indicates the temperature of February the following year at stations located on Spitsbergen and Jan Mayen. These correlations are negative (r ~ -0.55 - -0.50). The reason for occurrence of such correlations is not clear. The changeability of winter SST in the central part of the Norwegian Sea explains from 20% (Hornsund) to 32% (Bjornoya) of changeability in annual air temperature at the above mentioned stations in the same year and from 34% (Jan Mayen) to 41% (Hornsund) of changeability in annual air temperature in the following year. The increased level of explanation of changeability in air temperature the following year influenced by winter SST is connected with the delayed flowing of the Atlantic waters to high latitudes carried with the Norwegian Current and the West Spitsbergen Current.
This article presents the characteristic of the course of oceanicity index (Oc) in the region of the South Shetlands and its correlation with ENSO. The research made use of reconstructed by Lagun and Marshall (2001) series of monthly air temperatures at Bellingshausen station (1947-2000). The values of Oc have been calculated both for a calendar and hydrologic years (May - April) with a formulae given by Marsz (1995). Series of Southern Oscillation indexes (SOI) obtained from CRU has been used to examine correlation between Oc and ENSO. Periods of smaller and greater changes in Oc index were observed to take place one following another in the said period (Fig. 1) and a good proportion of the years was marked by ultraoceanicity. A posotive trend appearing in the series turned to be not statistically significant (Fig. 3). The analysis showed 2-year and 6-year periodiciy in the series of Oc index. Correlation between oceanicity index and mean annual air temperature (Fig. 2) and minimum temperature is characterised by high statistical significance. The fact that most significant correlation occurs in winter may prove that changes in ice condition have great influence on the increase in the frequency of occurrence of fresh sea air masses. The obtained results point to a tendency that the increase in air temperature in the region of the South Shetlands and the northern coast of the Antarctic Peninsula is followed by the increase in the transport of heat from the ocean to the atmosphere, represented by the increase in oceanicity index. At this stage we obtain quite paradoxical picture, i.e. the increase in the transfer of heat from the surface of the ocean should be accompanied by great rise in air temperature in winter, that is in the period when the intensity of heat transfer from the ocean to the atmosphere reaches greatest values. However, the analysis of trends indicated that the greatest rise in temperature was observed in the warmest month and in summer temperatures, that is in the periods when the heat transfer from the ocean to the atmosphere was least intensive. This means, that a possible cause ? effect sequence relating the increase in air temperature to the intensity of ocean influence observed in this area must be more comlicated than it is usually observed. Quite clear correlations may by noted here, although occurring with a long, 2-year time shift between the Oc and SOI. Such a great time shift suggests that the correlation between those variables cannot by governed by direct atmospheric circulation but there must be an in direct inertion linking element that retards the effect of temperature increase. The only possible link of this type ocean. The mechanisms that cause the shift of the maximum increase in the transfer of heat from the ocean to the air in winter to the increase in air temperature in summer are not clear. The co-author research results obtained so far seem to indicate that the mechanism responsible for the shift may be attributed to large scale changes in sea surface temperature reflected in changes in sea ice cover extent and its concentration.
On the Antarctic the annual course of air temperature shows a considerable spatial differentiation. Over the inland the course of temperature during the year is conditioned by insolation-radiational factors. On the coast the role of circulation factors connected with the advection of air masses from above the ocean or from the interior of the continent. In the paper mean monthly air temperatures from 56 stations making standard meteorological observations and from 38 automatic weather stations (AWS) have been used. On the Antarctic there types of annual air temperature courses can be distinguished: Oceanic - characterised by positive air temperatures in the summer season with the highest temperatures in February and by mild temperatures in the winter months (to -10°C). As a result of the ocean influence spring is considerable colder then autumn. The annual amplitudes are small (to 10-15°C). This type occurs on the western coast of the Antarctic Peninsula and on the subantarctic islands. Continental - with very low air temperatures. The warmest month is December with temperatures below -30°C in the interior of the continent. In winter the lowest mean monthly temperatures reach -70°C. The temperature frequently increases in the middle of winter; this phenomenon is called kernlose winter. The annual amplitude of air temperature is not high and in the interior its value reaches 30-35°C. The continental type includes the whole Antarctic except the narrow coastal belt. Coastal - characterised by air temperature around 0°C in the summer period. The warmest month is January. The lowest temperatures occur in January (-30° do -40°C). The growth of temperature in spring delays the heat uptake for the melting of sea ice. The annual amplitude of the air temperature is quite high and exceeds 20°C. Due to the influence of circulation factors on the Antarctic the annual course of the air temperature shows a large variability from year to year.
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