Christian Wetzel

ACSYS 1998 - Air mass modification in on-ice air flows north of Fram Strait: meteorological measurements of the research aircraft Falcon

Project: Field Data of the Meteorological Institute, University of HamburgnThe Physical Meteorology Division of the Meteorological Institute is regularly conducting or takingnpart in field experiments with strong focus on high latitudes. Measurements are performed bynaircraft, radiosondes or buoys and at land, ship and ice stations.nnPublished data sets incorporate aircraft measurements of turbulent fluxes and standardnmeteorological parameters of high temporal and spatial resolution. These measurements are supportednby frequent radiosonde ascents and station and ship data in the according region. Another group ofndata sets consists of measurements by autonomous buoys of different complexity on sea ice and ocean.nSummary: The field experiment ACSYS 1998 took place in the Greenland Sea west of Spitsbergen from 10 to 25 March 1998. It was planned and organized by scientists of the Meteorological Institute of the University of Hamburg within the national research project ACSYS (Arctic Climate System Study) which was funded by the German Bundesministerium fuer Bildung, Wissenschaft, Forschung und Technologie (BMBF). The national ACSYS project is part of the international ACSYS research program which is a sub-program of the World Climate Research Program (WCRP).nnThe objective of the ACSYS 1989 field experiment was the investigation of the atmospheric boundary layer in case of on-ice air flow in wintertime. Cyclones, reaching the Arctic sea ice from the Greenland Sea or Barents Sea are the strongest synoptic-scale weather signals in the Arctic region. They transport warm, moist and cloudy air from the open water to the Arctic shield. Especially in wintertime when the temperature contrast between the ocean and the ice surface is large the effects in the boundary layer over the ice are also significant.nnThe research aircraft Falcon performed six flight missions from 11 to 21 March measuring meteorological parameters and turbulent fluxes.