Intercomparison of integrated water vapor estimative from multi-sensor in Amazonian regions

摘要

Water vapor is an atmospheric component of major interest in atmospheric science, because it affects the energy budget and plays a key role in the several atmospheric processes. The Amazonian region is one of the most humid on the planet and land use change is able to affect the hydrologic cycle in several areas and consequently to generate severe modifications in the global climate. Within this context, accessing the error associated with atmospheric humidity measurement and the validation of IWV quantification from different techniques is very important in these regions. Using data collected during RACCI/DRY-TO-WET (Radiation, Cloud, and Climate Interactions in Amazonia during the DRY-TO-WET Transition Season) an experiment carried out in Southwestern Amazonia in 2002, this paper presents quality analysis of IWV (Integrated Water Vapor) measurements from RS80 radiosondes, a suite of GPS (Global Positioning System) receivers, an AERONET (AErosol RObotic NETwork) solar radiometer, and humidity sounding from HSB (Humidity Sounder for Brazil) aboard the AQUA satellite. When compared to RS80 IWV values, the RMS (Root Mean Square) from the AERONET and HSB sensor and GPS are to the order of 2.7, 7.7 and 4.3 kg m-2, respectively. The difference generated between IWV from the GPS receiver and RS80 during daytime was larger than the nighttime period due to the combination of the influence of high ionospheric activity during the RACCI experiment and a daytime drier bias from the RS80.