Validation of integrated water vapor using independent measurement techniques

Ground-based GPS for climate and NWP (Numerical Weather Prediction) applica tions require Integrated Water Vapor (IWV) data sets from independent instr uments continuously available for quality control and accuracy estimation. To meet the general need for high-quality water vapor information the WCRP/ Global Water Vapor Project (GVaP) was initiated, which includes the establi shment of reference observation stations. The Deutscher Wetterdienst is set ting up the Meteorologisches Observatorium Lindenberg as validation site. First results of an intended continuous monitoring and validation of IWV ar e shown using GPS, radiosonde, microwave profiler, and microwave radiometer measurements. (C) 2001 Elsevier Science Ltd. All rights reserved.