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Radiocarbon dating of fossil bats from Dobšina Ice Cave (Slovakia) and potential palaeoclimatic implications

Gradziński M., Hercman H., Peresviet-Soltan A., Zelinka J., Jelonek M.

Annales Societatis Geologorum Poloniae

2016

Vol. 86, No. 3

341--350

Although Dobšina Ice Cave (DIC, Carpathians, Slovakia) is located outside the high-mountain area, it hosts one of the most extensive blocks of perennial subterranean ice, the volume of which is estimated at more than 110,000 m3. Frozen bat remains were found in the lowermost part of the perennial ice block. They belong to Myotis blythii (Tomes) and the M. mystacinus morpho-group. The radiocarbon dating of bat soft tissues yielded ages of 1266–1074 cal. yr BP and 1173–969 cal. yr BP. The undetermined bat, found in the same part of the ice section in 2002, was previously dated at 1178–988 cal. yr BP (Clausen et al., 2007). The dates testify that the ice crystallized at the turn of the Dark Ages Cold Period and the Medieval Warm Period. The calculated accumulation rate of cave ice varies between 0.7 cm/year and 1.4 cm/year at that time, and is similar to the present ice accumulation rate in DIC. Constant crystallization of ice during the Medieval Warm Period is hypothesized to reflect dry summer seasons since the supply of relatively warm water in the summer is one of the key factors causing the erosion of cave ice. The uppermost sample was covered with 20.6 m of ice. Between ca 1065 cal. yr BP and the present day, the ice grew faster than between ca 1210 yr BP and ca 1065 yr BP by a factor of 1.3–1.8. This may have resulted from conditions favourable for ice accumulation during the Little Ice Age.

Klimat Arktyki w późnym glacjale i holocenie

Marsz A. A.

Problemy Klimatologii Polarnej

2009

nr 19

33-79

Praca referuje wyniki badań nad zmianami klimatycznymi w Arktyce, jakie zachodziły od początku późnego glacjału do momentu rozpoczęcia obserwacji instrumentalnych. Większą uwagę skupiono na zmianach klimatycznych, jakie miały miejsce w ciągu ostatnich 2500 lat. Zwrócono również uwagę na synchro-niczność zmian klimatycznych w Arktyce i wyraźnie rysujące się związki między zwiększonym dopływem wód atlantyckich do Arktyki, a kolejnymi fazami ociepleń.

This work presents an overview of literature devoted to presenting the results of research into climatic changes in the Arctic noted from the beginning of Late Glacial up to the moment when instrumental observation started. Greater emphasis was put on climatic changes which occurred during last 2000-2500 years. It was noted that the climatic changes in the Arctic were synchronical, that the rate of changes from the cooler seasons to the warmer ones and in the other way was fast and that the correlations between the increased import of the Atlantic waters to the Arctic and the following phases of warming were clear. The final part presented how the intensity of the Atlantic waters inflow influences the way the ice cover controls the mechanism of climatic changes in the Arctic.