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Wpływ warunków pogodowych na zmionność ablacji lodowców Waldemara i Ireny (NW Spitsbergen) w sezonie latnim 2003 roku

Sobota I.

Problemy Klimatologii Polarnej

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2004

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nr 14

95-106

EN

The paper presents the results of meteorological measurements carried out in the Kaffioyra Plain in the summer season of 2003. The main meteorological observations were conducted in N.Copernicus Polar Station, situated in northern part of the Kaffioyra (NW Spitsbergen). The paper also presents the results of ablation measurements on the Waldemar Glacier and Irene Glacier, which are located at Kaffioyra Region. The mean air temperature in the summer period (21.07. to 31.08.2003) was 6.1°C and was visibly higher then the long-term average. The sum of precipitation in this time was 74 mm and was higher then the long-term average. The comparison between summer season 2003 and mean values from the years 1975-2003 in the common period shows that this season was characterised by air temperature higher then many year?s values. The Waldemar Glacier and Irene Glacier are located in the northern part of the Oscar II Land, northwestern Spitsbergen. In spite of small areas of these glaciers, there is great spatial variation of ablation. Both Waldemar Glacier and Irene Glacier area and the height difference between the accumulation zone and the ablation area are relatively small. Nevertheless, spatial variation of ablation is observed. In this summer season the highest ablation values of Waldemar Glacier were noted in the ablation area of the glacier up to the altitude of about 250 m a.s.l., as well as at the foot of its medial moraine. The highest ablation values of Irene Glacier were noted in the ablation area of the glacier up to the altitude of about 300 m a.s.l.. During the analysed season a high average air temperature was observed. It resulted in increased ablation if compared to the previous seasons. Average air temperature and local glacier conditions were accepted as the main factors of ablation. The glacier average total summer ablation of Waldemar Glacier was 118.1 cm w.e. And Irene Glacier 111.1 cm w.e., respectively. The main meteorological parameters, which have an influence on ablation, are air temperature, wind velocity, insolation and participation. But it must be stressed that these parameters are clearly determined by local conditions of glaciers such as hypsometry, solar exposition, slope as well as density and the course of supraglacial streams.

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Warunki meteorologiczne na Lodowcu Waldemara (NW Spitsbergen) w sezonie letnim 1999 roku

Kejna M.

Problemy Klimatologii Polarnej

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2001

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nr 11

55-65

EN

The meteorological measurements were carried out on NW Spitsbergen on the Waldemar Glacier (surface 2.66 km2) in three points: ATA (133 m a.s.l., marginal zone), LW1 (130 m a.s.l., snout of glacier), LW2 (380 m a.s.l., firn part). The base station of Toruń Polar Expedition is situated on the north part of Kaffioyra (KH, 11 m a.s.l.), about 3 km away from glacier. The air temperature and relative air humidity were measured by termohigrographs in standard meteorological boxes, and precipitation by Hellmanns pluwiometer in the period 14.07-8.09.1999. The weather conditions on the Kaffiöyra region are determined by solar and circulation factors. In the summer season 1999 north and east advection of air masses dominated. The meteorological conditions on Waldemar Glacier are formed by the influence of two contrasting environments: the glacier and its moraine foreground. The mean air temperature in summer 1999 at the Kaffiöyra equaled 5.4°C and at the moraine of the Waldemar Glacier (ATA) 5.2°C. On the glacier the air temperature was much lower, and on the snout (LW1) was 4.5°C and decreases with the altitude (LW2 3.2°C) . The average gradient of air temperature between LW1 and LW2 stands was 0.53°C/100 m. Between the warmed up dark moraine ground (ATA) and the melted surface of the glacier a ?thermal jump? occurred (0.4°C on the distance 160 m). The highest maximum of air temperature at KH was 18.1°C, and on the Waldemar Glacier 16.4°C (LW1) and 16.5°C (LW2). The relative air humidity on Spitsbergen are formed under the influence of oceanic water and foehn phenomena. In summer season 1999 the mean relative air humidity was 84% at the Kaffioyra and increased with the altitude on the Waldemar Glacier (LW1 ? 86%, LW2 ?89%). In the period 21-07-31.08 at the Kaffioyra sums of the precipitation equaled 58.4 mm and on the glacier: 85.2 mm (133 m a.s.l.), 100,6 mm (233 m a.s.l.), 108.9 mm (380 m a.s.l.) and 131.8 mm (421 m a.s.l.). In summer season the meteorological conditions on the Waldemar Glacier show a large variability. It is a result of incoming air masses, warm from moraine foreground up the glacier and cool from the glacier plateau, from the interior of Spitsbergen.

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Wpływ warunków meteorologicznych na kształtowanie się odpływu powierzchniowego na Lodowcu Waldemara (NW Spitsbergen) latem 1997 roku

Brykała D., Araźny A.

Problemy Klimatologii Polarnej

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2000

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nr 10

139--158

EN

In the summer season 1997 during the 13rd Toruń Polar Expedition research works were carried out to investigate the dynamics of water run-off in a selected supraglacial stream on the Waldemar Glacier in comparison to the course of meteorological conditions and ablation (figs l and 3). We have tried to present also the temporal and spatial changes in the structure of surface run-off on the glacier. Over the Kaffiöyra region in the whole summer season, especially in August, cyclonic weather dominated. Its characteristic features were: small sunshine duration (16.6 percent of the possible value), high cloudiness (8.5 on the scale l-10), high frequency of strong winds (mean velocity 5.4 m/s), and very abundant and intensive atmospheric precipitation (sum 122.5 mm) (fig. 2). The ablation is considerably differentiated spatially and temporary. In the studied period its highest value was observed below 250 m above sea level, and the lowest one on 430 m above sea level (19 cm e.w.). On 150 m above sea level, at the hydrometric stand, the ablation was 119 cm e.w. The gradient of ablation varied from 0.3 cm to 3.6 cm e.w. per 100 m height in the selected periods (Sobota 1998). The three big streams marked on fig. 3 (A. B and e) have the greatest role in the formation of the surface drainage system of the Waldemar Glacier. Daily measurements of the discharge intensity were made on the 508.6 m long supraglacial stream. The stationary measurement point was on 147m above sea level, about 160 m above the place where the stream leaves the snout of the glacier. The spatial differentiation induced the authors to distinguish five glacio-hydrological zones on the Waldemar Glacier: intensive ablation. Organized run-off, snow patches, slush, and dry snow (fig, 4, tab. l). The main criteria to distinguish the individual zones were the followings: morphology of the glacial surface, pollution degree of the snow by moraine material, and types of the surface run-off. Table 2 presents the correlation coefficients between the meteorological parameters and ablation and the discharge in the analysed stream. In most of the cases the correlation between the individual parameters is high (r > 0.77). The highest values of the correlation coefficient occur between the discharge and the course of temperature and ablation.