The Winter Arctic Polynja Study was carried out during Polarstern cruise ARK XIX/1 in spring 2003 in the Storfjord and northern Fram Strait region. Measurements in the atmospheric boundary layer over leads were performed from a mast mounted at Polarstern and with the helicopter borne turbulence probe HELIPOD.The ship based measurements aimed to quantify the effect of leads and polynjas on the surface layer fluxes above the mainly closed sea ice cover.  The primary aim of the Helipod flights was to measure the lead influence in the entire atmospheric boundary layer.

The Turbulence Measuring System (TMS) consists of a 17 m mast, installed on the Polarstern bow crane. This mast usually is fixed horizontally during the cruise, but for operation it can be moved forward and turned into vertical position by a hydraulic and a tackle system.

At five heigths between 3 and 20 m above the sea surface, five USAT-3 sonic sensors (METEK) are mounted to measure the turbulent fluctuations of wind and temperature. Five Pt-100 temperature sensors determine the mean temperature profile. Additionally, a Lyman-alpha is installed at a heigth of 3 m to measure the turbulent humidity signals. In addition the absolute humidity is measured by a dew point mirror.