WEATHER CONDITIONS IN CALYPSOBYEN IN THE SUMMER 1993 (WEST SPITSBERGEN)

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1 Pawei CZUBLA Institute of Earth Sciences Maria Curie-Skłodowska University Akademicka Lublin, P O L A N D W>prawy Geograficzne na Spitsbergen UMCS, Lublin, 1994 WEATHER CONDITIONS IN CALYPSOBYEN IN THE SUMMER 1993 (WEST SPITSBERGEN) INTRODUCTION During Geographical Expedition VIII to Spitsbergen organized by Maria Curie-Skłodowska University in 1993 there were made some observations of basic weather parameteres in Calypsobyen (cp ' N, X ' E). The place of measurements, which was a meteorological garden, was situated on a marine terrace with the soil cover and vegetation characteristic for spotted tundra (Rzętkowska 1987) at 23 m a.s.l. and about 200 m away from the shore of Recherche fiord (Szczęsny et. al. 1989) in the Bellsund region. In the period of 15 July August 1993 three times a day and night at 7 a.m., 1 p.m. and 7 p.m. - the local time (6 a.m., 12 a.m. and 6 p.m. GMT respectively) there were observed the following meteorological parameteres: - atmospheric air temperature 200 cm high over the ground, - maximum and minimum temperatures 200 cm high over the ground, - relative humidity of air, - extreme temperatures 5 cm high over the ground, - extent and kind of cloud cover, - occurence and amount of precipitation, - wind velocity and direction, - ground temperature at the depth of 5, 10, 20, 50, 100 and 150 cm. Continuous observations of air temperature and humidity were made 2 m high by the use of thermohigrograph. Day and night mean values of some meteorological elements are presented in Table 1 and extreme day and night as well as mean values for the whole period of observations are included in Table 2. This paper is continuation of some earlier works carried out in this area (Bartoszewski, Siwek 1992; Brazdil et al. 1991; Czaban 1990; Gluza 1987a, 1987b, 19a, 19b, 1989; Rodzik 1989; Rodzik, Ryżyk 1987; Siwek 1991; Siwek, Paczos 1990) and presents preliminary results of the observations and measurements of some meteorological elements. 55

2 THERMAL CONDITIONS Current temperature was read in the meteorological stand 2 m high over the ground. Extreme (minimum and maximum) temperetures were measured: 5 and 200 cm high. The average air temperature during the observations (15 July-22 August) was 5.1 C. The day and night mean value changed from 2.4 C (26 July with the winds mostly from the East of the average velocity 5.3 m/s) to 9.2 C on 15 July (the day of the average wind velocity 2.3 m/s). The difference between the average temperatures of the warmest day and the coldest one was 6.8 C. Temperature variability from day to day was 1.1 C (from C in extreme cases). 15 July - the warmest day of observations was also the day of highest maximum temperatures (13.5 C at the height of 200 cm and 16.0 C at the height of 5 cm). The lowest maximum temperature 4.0 C (variability 9.5 C) at the height of 200 cm took place on 25 July. At the height of 5 cm the temperature was 5.8 C (variability 10.2 C) on 22 August. The average maximum temperatures were 7.7 C and 9.3 C at the heights 200 cm and 5 cm respectively. Minimum temperatures changed from -0.5 C (26 and 27 July) to 7.0 C (15 July) at the height of 2 m and from 0.5 C (26 July) also to 7.0 C (15 and 16 July) just over the ground. At the height of 200 cm there was observed greater variability of the minimum temperature (7.5 C) but its average value (2.8 C) was lover than that at the height of 5 cm (6.5 C and 3.6 C respectively). AIR H U M I D I T Y Air humidity is characterized by two parameters: relative humidity and water vapour pressure. The average relative humidity of air in the study period was.2% and changed from 67% on 13 August to 92% on 29 July. Variability of relative humidity was 25%. During a 39 day obserwation series relative humidity exceeded or reached 90% six times and was lower than 75% during only two days. Water vapour pressure changed from 6.4 hpa (25, 26 July and 22 August) to 9.2 hpa on 29 July (variability 2.8 hpa). The average value of water vapour pressure was 7.5 hpa. SKY C L O U D COVER The extent of sky cloud cover was observed in the period 28 July-22 August. It was recorded in the scale from 0 (clear sky) to 10 (sky covered completely with 56

3 clouds). During the observations the average day and night cloud cover was 8.1 changing from 3.0 (13 August) to 10. The maximum sky cloud cover took place on 2-8 and August. There was not even one sunny day i. e. with the cloud cover <2 but there were as many as 15 cloudy days (the cloud cover was >8). PRECIPITATION The total precipitation was 59.6 mm during the observation period. There were 19 days with precipitation of which 10 days with precipitation below 0.1 mm, 5 days with mm, 2 days with 1-10 mm and two days over 10 mm. The record precipitation, which was 36.3 mm (with the average wind velocity 7.3 m/s), took place on 7 August. That is absolute maximum of day and night precipitation recorded in Calypsobyen during the summer geographical expeditons to Spitsbergen by Maria Curie-Sklodowska University in the period Besides, the precipitation exceeding 10 mm was recorded only three times during eight observation series. It was in 1989: 4 September mm, 2 August mm (Czaban 1990) and in August mm (Tab. 1). WIND VELOCITY A N D D I R E C T I O N During the observation period the average wind velocity was 5.8 m/s. The day and night values were differentiated from 0.7 m/s (22 August) to 21.0 m/s (12 August). Variability of wind velocity was as much as 20.3 m/s. The wind record velocity at the time of observations (7 a.m., 1 p.m. and 7 p.m.) was over 25 m/s (11-13 August). Winds from the East and North were the most frequent and they constituted 34.2% and 22.2% respecitvely. Winds from the west and south-west were scarce (1.7%). Atmospheric calm constituted 3.4% of observations. South-east fóhn winds (10.1 m/s) and east winds (9.5 m/s) were the strongest while north-east winds (1.2 m/s) were the faintest. An ice pack in Recherche fiord transported by the Sorkapp Current (Swerpel 19) and pushed into the bay by winds and sea water movements was an important element of the meteorological situation in Calypsobyen in the summer The presence of ice, which finally disappeared at the beginning of August when a precipitation period came, caused almost continuous fog over the fiord. In the morning its reach was, as a rule, larger. It appeared also on the surface of Calypsostranda. The fact of enormous transparence of air should be mentioned too. When there was no fog, visibility reached km or even more. 57

4 REFERENCES Bartoszewski S., Siwek К., 1992: Meteorological conditions of the Scott River outflow in the summer 1990 (Western Spitsbergen). Wyprawy Geograficzne na Spitsbergen, UMCS Lublin: Brazdil R., Prosek P., Paczos S., Siwek К., 1991: Comparison of meteorological conditions in Calypsobyen and Reindalen in summer Wyprawy Geograficzne na Spitsbergen, UMCS Lublin: Czaban P., 1990: Weather conditions in Calypsobyenin the summer Wyprawy Geograficzne na Spitsbergen, U M C S Lublin: Gluza A. F., 1987a: Prędkość i kierunek wiatru w lipcu i sierpniu 1986 r. w Calypsobyen (Zachodni Spitsbergen). XIV Sympozjum Polarne, Lublin: Gluza A. F., 1987b: Zachmurzenie i częstość występowania poszczególnych rodzajów chmur w lipcu i sierpniu 1986 r. w Calypsobyen (Zachodni Spitsbergen). XIV Sympozjum Polarne, Lublin: Gluza A. F., 19a: Warunki pogodowe w sezonie letnim 1987 w Calypsobyen (Zachodni Spitsbergen). Wyprawy Geograficzne na Spitsbergen, UMCS Lublin: Gluza A. F.. 19b: Prędkość i kierunek wiatru w sezonie letnim 1987 w Calypsobyen (Zachodni Spitsbergen). Wyprawy Geograficzne na Spitsbergen, UMCS Lublin: Gluza A. F., 1989: Warunki pogodowe w lipcu, sierpniu i wrześniu 19 roku w Calypsobyen (Zachodni Spitsbergen). Wyprawy Geograficzne na Spitsbergen, UMCS Lublin: Rodzik J., 1989: Termiczno-opadowe zróżnicowanie południowego obrzeżenia Bellsundu w sezonie letnio-jesiennym 19 roku. Wyprawy Geograficzne na Spitsbergen, UMCS Lublin: Rodzik J., Ryży к E., 1987: Zróżnicowanie przestrzenne warunków termiczno-wilgotnościowych południowego obrzeżenia Bellsundu w sierpniu 1986 r. XIV Sympozjum Polarne, Lublin: Rzętkowska A., 1987: Wstępna charakterystyka roślinności rejonu Calypsostranda (Wedel Jarlsberg Land, Spitsbergen). XIV Sympozjum Polarne, Lublin: Siwek K., Paczos S., 1990: Differentiation of Calypsostranda thermal and humidity conditons in the summer 1989 (Western Spitsbergen). Wyprawy Geograficzne na Spitsbergen, UMCS Lublin: Siwek К., 1991: The weather conditions in Calypsobyen in the summer Wyprawy Geograficzne na Spitsbergen, U M C S Lublin: Swerpel S., 19: The Hornsund fiord. Water masses. Polish Polar Research, vol. 6, no. 4: Szczęsny R., DzierżekJ., HarasimukM., NitychorukJ., Pękala К., Repelewska-Pękalowa J., 1989: Photogeological map of the Renardbreen, Scotlbreen and Blomlibreen forefield (Wedel Jarlsberg Land, Spitsbergen 1 :10000). Wydawnictwa geologiczne Warszawa. STRESZCZENIE Praca niniejsza zawiera wstępne wyniki obserwacji i pomiarów podstawowych parametrów meteorologicznych, które przeprowadzono w Calypsobyen podczas VIII Wyprawy Geograficznej UMCS na Spitsbergen w 1993 r. Trzykrotnie w ciągu doby (o 7.00, i 19.00) w okresie 15 VII-22 VIII obserwowano temperaturę i wilgotność powietrza atmosferycznego, wielkość i rodzaj zachmurzenia, wielkość opadu atmosferycznego, prędkość i kierunek wiatru oraz temperaturę gruntu na kilku głębokościach. Ponadto przy użyciu termohigrografu prowadzona była ciągła obserwacja temperatury powietrza i wilgotności na wysokości 2 m. W tekście przedstawiono krótkie opracowanie poszczególnych elementów meteorologicznych. Tabela 1. zawiera zestawienie ich średnich wartości dobowych, natomiast wartości ekstremalne i średnie za okres obserwacji zestawione są w Tabeli 2. 58

5 Tab. 1. Day and night mean values of some meteorological elements in Calypsobyen in the period 15 July-22 August date, 2 - atmospheric air temperature ( C), 3 - minimum temperature at the height of 200 cm ( C), 4 - maximum temperature at the height of 200 cm ( C), 5 - minimum temperature at the height of 5 cm ( C), 6 - maximum temperature at the height of 5 cm ( C), 7 - relative humidity (%), 8 - water vapour pressure (hpa), 9 - wind velocity (m/s), 10 - cloud cover, 11 - precipitation (mm). 2 9,2 4,8 4,3 2,7 2,4 5,4 6,1 5,8 3,8 6,2 7,2 5,7 5,6 5,7 8,7 со 6,2 4,4 4,4 3,9 3 0,5 1,0 1,0 2,0 2,0 0,3 "0,5-0,5 3,6 4,2 2,7 0,2 4,2 3,9 2,8 1,2 3, ,0 8,8 8,6 6,6 5,9 6,9 6,6 8,8 9,3 12,2 11,0 6,6 5,7 5,8 5 2,0 0,5 1,2 2,6 3,9 3,6 3,6 3,8 2,4 3, , ,5 12,0 10,5 9, ,5 9,9 11,6 8,4 7,4 6,2 8,9 12,8 6,8 6,3 5, ,6 7,8 7,4 6,8 7,1 6,4 6,4 7,9 9,2 8,4 7,1 7,7 9,1 8,8 7,4 7,7 7,8 6,8 6,4 9 2,3 2,8 4,3 4,2 1,8 3,8 2,8 2,2 4,3 1 5,2 1 21,0 1 12,3 7,2 o" VII 1 6 VII 17 VII 1 8 VII 1 9 VII 2 0 VII 21 VII 2 2 VII 2 3 VII 2 4 VII 2 5 VII 2 6 VII 2 7 VII 2 8 VII 2 9 VII 3 0 VII 31 VII 1 VIII 2 VIII 3 VIII 4 VIII 5 VIII 6 VIII' 7 VIII 8 VIII 9 VIII 1 0 VIII 11 VIII 12 VIII 1 3 VIII 1 4 VIII 1 5 VIII 1 6 VIII 17 VIII 1 8 VIII 1 9 VIII 2 0 VIII 21 VIII 2 2 VIII ,3 7,7 0,7 0,3 0,4 36,3 5,4 0,2 12,4 0,6 59

6 Tab. 2. Mean (a) and extreme (b - maximum, с - minimum) values of some meteorological elements in Calypsobyen in the period 15 July - 22 August 1993 a b с Atmospheric air temperature at the height of 200 cm ( C) (15 July) 2.4 (26 July) Minimum temperature at the height of 200 cm ("С) (15 July) -0.5 (26 and 27 July) Maximum temperature at the height of 200 cm ("С) (15 July) 4.0 (25 July) Minimum temperature at the height of 5 cm ("С) (15 and 16 July) 0.5 (26 July) Maximum temperature at the height of 5 cm CO (15 July) 5.8 (22 August) Atmospheric air relative humidity (%) (29 July) 67.0 (13 August) Water vapour pressure (hpa) (29 July) 6.4 (25, 26 July; 22 August) Wind velocity (m/s) (12 August) 0.7 (22 August) Cloud cover (9 days) 3.0 (13 August) Precipitation (mm) 36.3 (7 August) 60