Tropospheric Water Vapor Transport as determined from Airborne Lidar Measurements

Kurzfassung

First collocated measurements were performed by the novel four-wavelength differential absorption lidar WALES and the scanning 2 μm Doppler wind lidar onboard the DLR research aircraft Falcon during the European THORPEX Regional Campaign in 2007. One mission which was characterized by exceptionally high data coverage (47% for the specific humidity q and 63% for the horizontal wind speed v) was selected to calculate the advective transport of atmospheric moisture qvh along a 1600 km section in the warm sector of an extratropical cyclone. The observations are compared with special onehourly model data calculated by the ECMWF integrated forecast system. Along the cross-section, the model underestimates the wind speed on average by -2.8 % (-0.6 m/s) and overestimates the moisture at dry layers and in the boundary layer, which results in a wet bias of 17.1 % (0.2 g/kg). Nevertheless, the ECMWF model reproduces quantitatively the horizontally averaged moisture transport in the warm sector. There, the superposition of high low-level humidity and the increasing wind velocities with height resulted in a deep tropospheric layer of enhanced water vapor transport qv. The observed moisture transport is variable and possesses a maximum of qv = 130 g/kg m/s in the lower troposphere. The pathways of the moisture transport from south-west via several branches of different geographical origin are identified by Lagrangian trajectories and by high values of the vertically averaged tropospheric moisture transport.

Verfügbare Versionen dieses Eintrags

• Tropospheric Water Vapor Transport as determined from Airborne Lidar Measurements. (deposited 06 Dez 2010 14:42) [Gegenwärtig angezeigt]
  • Airborne lidar observations in the inflow region of a warm conveyor belt. (deposited 25 Jan 2011 09:30)