ICE CONDITIONS IN NOTTINGHAMBUKTA DURING SEASONS

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Barbara WISNIEWSKA Chair of Genetic University of Gdańsk Kładki 24, 80-882 Gdańsk POLAND POLISH POLAR STUDIES X X V I Polar S y m p o s i u m ЭШжУ Lublin, June 1999 ICE CONDITIONS IN NOTTINGHAMBUKTA

1 Barbara WISNIEWSKA Chair of Genetic University of Gdańsk Kładki 24, Gdańsk POLAND POLISH POLAR STUDIES X X V I Polar S y m p o s i u m ЭШжУ Lublin, June 1999 ICE CONDITIONS IN NOTTINGHAMBUKTA DURING SEASONS WARUNKI LODOWE W ZATOCE NOTTINGHAM W LATACH ABSTRACT Nottinghambukta - a bay of watt type, is situated in the region of southern Spitsbergen and makes up a very complicated natural environment. The proof of this statement is that there were unrepeatable unique ice conditions expressed by a variable level of sediment freezing during the years of the research. INTRODUCTION The Nottinghambukta is situated in the region of southern Spitsbergen, by the mouth of Hordsund Fjord. It is fenced off from Greenland Sea by the strip of Dunoyane islands and skerries. The western border is constituted by moraine of the nearby Werenskiold Glacier, the southern border - the strip of tundra. Within the many coast types occurring in Spitsbergen - watty like including Nottinghambukta, are situated in the depth of the fjords or their spurs (Węsławski 1993). The specific current conditions in Nottinghambukta are shaped by the warm West Spitsbergen sea current (the final arm of Gulfstrom), the cold Sörkap sea current, tides, nearby located the Werenskiold Glacier and seasonal rivers (Legeżyńska 1984; Różycki, Gruszczyński 1986; Krawczyk et al. 1990; Krawczyk, Wach 1993; Krawczyk et al. 1994). During the spring-summer seasons systematic observations of ice cover and the level of frozen sediments in Nottinghambukta were conducted.

324 Barbara Wiśniewska MATERIALS AND METHODS During the following seasons of observations there were test bore-holes taken in the ice sheet of the bay.

2 324 Barbara Wiśniewska MATERIALS AND METHODS During the following seasons of observations there were test bore-holes taken in the ice sheet of the bay. The exception was the winter season in 1993, when the bay was not frozen. After taking the bore-holes the thickness of the ice sheet was estimated with particular attention to thin sediments layers that had appeared. Then the structure and the thickness of the surface ice cover and unfrozen layers and the layer between the ice and the sediment were described. RESULTS In the examined seasons, spring season conditions in the bay were the following: SEASON The bay was ice free, probably it was the after-effect of strong storms during autumn and winter. The top sediment layer up to the depth of 0.1 m was defrosted, deeper still permafrost prevailed. This situation took place on the 14 t h of May when observations were begun; on the 3 r d of June the permafrost began retreating.

325 Ice c o n d i t i o n s i n N o t t i n g h a m b u k t a d u r i n g 1 9 9 3-1 9 9 8 s e a s o n s SEASON 1994 The bay was covered by about 1.0 m ice layer.

3 325 Ice c o n d i t i o n s i n N o t t i n g h a m b u k t a d u r i n g s e a s o n s SEASON 1994 The bay was covered by about 1.0 m ice layer. The test bore-holes were taken in several test points. There was no permafrost up to the depth of 0.5 m in the sediment. Longer cores of sediments were not taken. The observations were taken on the 19 th and 26 t h of April. The bore-holes were made at nine locations, from which four with their different cores are showed on the schemes (No. 1, No. 2, No. 3, No. 4). SEASON 1995 As in the previous season there was an ice cover on the bay, the ice layer was about 0.75 m thick. The observations started on 18 th April. At the depth of 0.5 m from the top there was a thin sediment layer of m thick. Under the ice layer there was a thin water layer (0.3 m). Under that layer there was 0.03 m frost sediment and underneath there was another wet sediment layer of 0.04 m thick. Deeper still permafrost was observed (scheme No. 5). The Cores Structures 1994 dlm «-tee d m 0.25 Unfrozen sediment Icc with sediment k AM. 3 «-less <- Frozen sediment f- Icc mm _ <-Icc _ neic«mcc k- Very wet muddy sediment <r Icc with a iitüc amount of idiment S c h e m e No. 1, S c h e m e No. 3,

Barbara Wiśniewska 326 dlml The Core Structure 1995 «ta «- Ice with sediment «-Ice «-Water «- «- Frozen sediment «Wet sandy sediment At the end of May (the 29 t h of May) the top (0.

4 Barbara Wiśniewska 326 dlml The Core Structure 1995 «ta «- Ice with sediment «-Ice «-Water «- «- Frozen sediment «Wet sandy sediment At the end of May (the 29 t h of May) the top (0.5 m) ice layer melted, leaving the surface of the thin layer of sediment - that previously had been in the ice, the remaining 0.25 m ice layer was still existing. The level of freezing up of the layer was the same as that observed in April. But on June the 9 t h the bay was ice-free: the permafrost began retreating, but was present at the depth of 0.1 m from the surface of the sediment. On the 27 t h of June the sediment was thawing. Up to 1 m permafrost was not present. «Permafrost Scheme No SEASON 1996 When the first observations were made, the bay was covered by ice of 0.7 m thickness. Under the ice layer and the thin air layer of 0.02 m formated between the ice and sediment there was permafrost (scheme No. 6). At the another locations, where the research was conducted on May the 28 t h - under a 0.95m ice layer there was loose frozen sediment of 0.05 m thickness. Deeper there was permafrost (scheme No. 7). There was no ice cover at the mouth of the bay. The ice cover began to retreat at the end of May and in June the whole area of the bay was free of it. At the end of June permafrost had retreated. JLteL The Cores Structures 19% d[m] «Ice «-Ice Ice with a little amount of limem ta with sediment Air Permafrost «- Loose froze«sediment Permafrost Scheme No ; Scheme No

Ice conditions in Nottinghambukta during 1993-1998 seasons 327 SEASON 1 9 9 8 The observations were begun on the 19 th of May when the whole bay was covered by ice. Under the ice cover there was a 0.

5 Ice conditions in Nottinghambukta during seasons 327 SEASON The observations were begun on the 19 th of May when the whole bay was covered by ice. Under the ice cover there was a 0.4 m water layer and underneath melted sediment. The observations were taken up to the depth of 0.5 m but there was no permafrost (scheme No. 8). As in the previous case there was no permafrost in the location situated nearby the seashore (scheme No. 9). As the end of May the ice cover began melting and in the first decade of June the bay was not covered by ice. The Cores S(ructures 1998 <r Icc 9 8 Frozen muddy sediment 0.25 «-Icc f- Ice : ; - ; ' : i' Ice ШШШШ: «-Water -... ДSÄSlfcfilll^liW.. 1 i.к - л ж«.,.. <.. męm Wet sandy sediment i-'}/ Щ/ШШРШ f- Wet sandy sediment U-? Scheme No Scheme No REFERENCES KRAWCZYK W. E GŁOWACKI P., PULINA M. 1990: H y d r o c h e m i c a l d i u r n a l cycle o n t h e t u r n of s u m m e r a n d autumn in the Glacial River of Werenskiold, SW Spitsbergen. Wyprawy Geograficzne na Spitsbergen, UMCS, Lublin: KRAWCZYK W. Е., OPOŁKA-GĄDEK J. 1994: Suspended sediment concentrations in waters of the Werenskiold glacier basin in XXI Sympozjum Polarne, Warszawa: KRAWCZYK W. E., WACH J. 1993: Winter outflows of waters from the Werenskiold Glacier in hydrological year 1985/86. XX Sympozjum Polarne, Lublin: LEGEŻYŃSKA е., MOSKAL W., WĘSŁAWSKI J. M., LEGEŻYŃSKI P. 1984: W p ł y w w a r u n k ó w ś r o d o w i s k o w y c h n a rozmieszczenie fauny dennej w Zatoce Nottingham, Spitsbergen. Zeszyty Naukowe Wydz. Biol. i Nauk o Ziemi, UGd., Oceanografia, 10: RÓŻYCKI O., GRUSZCZYŃSKI M. 1986: Macrofauna associated with laminarians in the coastal waters of West Spitsbergen. Polish Polar Research, 7,4: WĘSŁAWSKI J. M. 1993: Podatność morskiego ekosystemu Svalbardu na zmianę klimatu. Rozprawy i monogr. Inst. Ocean., 3: 144.

328 Barbara Wiśniewska STRESZCZENIE Rezultaty badań prowadzonych w latach 1993-1998 pokazują, że w sezonach wiosenno-letnich (za wyjątkiem roku 1993) cala zatoka była pokryta lodem.

6 328 Barbara Wiśniewska STRESZCZENIE Rezultaty badań prowadzonych w latach pokazują, że w sezonach wiosenno-letnich (za wyjątkiem roku 1993) cala zatoka była pokryta lodem. Sprawiało to wrażenie analogicznej sytuacji lodowej w każdym sezonie. Analiza stopnia i sposobu zamarznięcia osadu oraz grubości pokrywy lodowej wskazuje jednak na duże zróżnicowanie. Stwarza to trudną sytuację drobnym zwierzętom zamieszkującym zatokę. Jest to jedna z przyczyn skłaniających do prowadzenia badań zmierzających do poznania zmienności sytuacji lodowej.

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