Using AIRS to assess the precipitable water vapor in global climate models (GCMs) with regional validation from SuomiNet

Results are presented that assess the accuracy of the AIRS PWV climatology using measurements from the SuomiNet network of ground-based GPS observations in the U.S. Southern Great Plains. The diurnal sampling error of the AIRS product is evaluated using 30 minute continuous sampling from the GPS network. The GPS network observations are used as a stable reference to assess trends in the AIRS L3 gridded PWV product for the nine year period 2003-2011. An anomalous trend in the AIRS L3 product is detected after 2007 which requires further investigation.