Inhaltszusammenfassung

Signatures of the katabatic wind on high-resolution satellite imagery can often been detected as streaks in the infrared brightness temperatures. The relation to the katabatic wind system is commonly thought to be caused by a wind pattern in the boundary layer, which leads to spatial variations of the snow drift intensity, thus influencing the temperature of the emitting surface and the emissitivity. Data of the aircraft based experiment KABEG'97 (Katabatic wind and boundary layer front exper...Signatures of the katabatic wind on high-resolution satellite imagery can often been detected as streaks in the infrared brightness temperatures. The relation to the katabatic wind system is commonly thought to be caused by a wind pattern in the boundary layer, which leads to spatial variations of the snow drift intensity, thus influencing the temperature of the emitting surface and the emissitivity. Data of the aircraft based experiment KABEG'97 (Katabatic wind and boundary layer front experiment around Greenland) performed in April/May 1997 are used to study the characteristics of these thermal streaks and their relation to boundary layer structures in detail. For katabatic wind flights during different synoptic situations and surface conditions with low-level jets with wind speeds up to 25 m/s the surface temperature patterns were found to agree with those found in the AVHRR data. Snow drift can be ruled out to be the primary reason for the streaks, and a connection to the surface topography was found instead. The katabatic streaks seem to be a signal of the surface inversion strength being related to the wind speed.» weiterlesen» einklappen

Autoren

Klassifikation

DDC Sachgruppe:
Naturwissenschaften