The Cryosphere www.the-cryosphere.net 1994-0416 1994-0424 3 1 2009 10.5194/tc-3-57-2009 http://www.the-cryosphere.net/3/57/2009/ http://www.the-cryosphere.net/3/57/2009/tc-3-57-2009.html http://www.the-cryosphere.net/3/57/2009/tc-3-57-2009.pdf 57 74 2009-03-20 Comparison of the meteorology and surface energy balance at Storbreen and Midtdalsbreen, two glaciers in southern Norway R. H. Giesen r.h.giesen@uu.nl L. M. Andreassen M. R. van den Broeke J. Oerlemans Institute for Marine and Atmospheric research Utrecht, Utrecht University, Princetonplein 5, 3584 CC Utrecht, The Netherlands Section for Glaciers, Snow and Ice, Norwegian Water Resources and Energy Directorate, P.O. Box 5091 Majorstua, 0316 Oslo, Norway Department of Geosciences, University of Oslo, P.O. Box 1047 Blindern, 0316 Oslo, Norway We compare 5 years of meteorological records from automatic weather stations (AWSs) on Storbreen and Midtdalsbreen, two glaciers in southern Norway, located approximately 120 km apart. The records are obtained from identical AWSs with an altitude difference of 120 m and cover the period September 2001 to September 2006. Air temperature at the AWS locations is found to be highly correlated, even with the seasonal cycle removed. The most striking difference between the two sites is the difference in wind climate. Midtdalsbreen is much more under influence of the large-scale circulation with wind speeds on average a factor 1.75 higher. On Storbreen, weaker katabatic winds are dominant. The main melt season is from May to September at both locations. During the melt season, incoming and net solar radiation are larger on Midtdalsbreen, whereas incoming and net longwave radiation are larger on Storbreen, primarily caused by thicker clouds on the latter. The turbulent fluxes are a factor 1.7 larger on Midtdalsbreen, mainly due to the higher wind speeds. Inter-daily fluctuations in the surface energy fluxes are very similar at the AWS sites. 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