Atmospheric Chemistry and Physics Discussions www.atmos-chem-phys-discuss.net 1680-7367 1680-7375 7 1 2007 10.5194/acpd-7-1261-2007 http://www.atmos-chem-phys-discuss.net/7/1261/2007/ http://www.atmos-chem-phys-discuss.net/7/1261/2007/acpd-7-1261-2007.html http://www.atmos-chem-phys-discuss.net/7/1261/2007/acpd-7-1261-2007.pdf 1261 1293 2007-01-25 Humidity observations in the Arctic troposphere over Ny-Ålesund, Svalbard based on 14 years of radiosonde data R. Treffeisen renate.treffeisen@awi.de R. Krejci J. Ström A. C. Engvall A. Herber L. W. Thomason Alfred Wegner Institute for Polar and Marine Research, Telegrafenberg A45, 14473 Potsdam, Germany Department of Meteorology (MISU), Stockholm University, S 106 91 Stockholm, Sweden ITM – Department of Applied Environmental Science, Stockholm University, S 106 91 Stockholm, Sweden Alfred Wegner Institute for Polar and Marine Research, Am Handelshafen 12, 27570 Bremerhaven, Germany NASA Langley Research Center Hampton, VA 23681-2199, USA Water vapour is an important component in the radiative balance of the polar atmosphere. We present a study covering fourteen-years of data of tropopsheric humidity profiles measured with standard radiosondes at Ny-Ålesund (78°55' N 11°52' E) during the period from 1991 to 2005. It is well known that relative humidity measurements are less reliable at cold temperatures when measured with standard radiosondes. 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