caa a22 4500 445800232 CHVBK 20180317145138.0 cr unu---uuuuu 170323e20111201xx s 000 0 eng 10.1007/s00704-011-0423-y doi (NATIONALLICENCE)springer-10.1007/s00704-011-0423-y Bednorz Ewa Institute of Physical Geography and Environmental Planning, Adam Mickiewicz University, ul. Dzięgielowa 27, 61-680, Poznań, Poland aut Occurrence of winter air temperature extremes in Central Spitsbergen [Elektronische Daten] [Ewa Bednorz] The occurrence of daily air temperature extremes in winter in Central Spitsbergen in the period 1975-2008 was analysed. The mean winter temperature was found to be increasing by approximately 1.65°C per decade. Negative extremes were becoming less frequent, decreasing at a rate of approximately 5days per decade, whereas the frequency of positive extremes showed a small (2days per decade) but insignificant positive trend. Furthermore, circulation patterns responsible for positive and negative temperature extremes were analysed. Composite maps of the sea level pressure (SLP) and 500-hPa geopotential heights (z500hPa) means and anomalies were constructed for the days with positive and negative extremes. Circulation patterns causing extremely warm winter days are characterised by a cyclonic centre or a low pressure trough over the Fram Strait. Cyclones located west of Spitsbergen with a warm sector over the archipelago bring warm air masses from the southern quadrant. On extremely cold days, the cyclone centres are usually located over the Barents Sea. This SLP pattern implies airflow from the north and northeast that brings cold Arctic air to the North Atlantic. Another factor in the occurrence of the temperature extremes in Central Spitsbergen is the sea-ice cover. Negative temperature extremes usually occur together with a high concentration of sea ice, particularly in the middle and end of winter. Springer-Verlag, 2011 Theoretical and Applied Climatology Springer Vienna 106/3-4(2011-12-01), 547-556 0177-798X 106:3-4<547 2011 106 704 https://doi.org/10.1007/s00704-011-0423-y text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00704-011-0423-y text/html Onlinezugriff via DOI NATIONALLICENCE 100 1- Bednorz Ewa Institute of Physical Geography and Environmental Planning, Adam Mickiewicz University, ul. Dzięgielowa 27, 61-680, Poznań, Poland aut NATIONALLICENCE 773 0- Theoretical and Applied Climatology Springer Vienna 106/3-4(2011-12-01), 547-556 0177-798X 106:3-4<547 2011 106 704 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer