Global Water Vapor Project (GVaP)

Blended global water vapor and cloud liquid water data sets (NVAP) using radiosonde, microwave and infrared satellite data with 1 x 1-degree resolution daily, pentad and monthly averages for the period 1988 - 1997 are available on tape or via FTP at the Langley DAAC.   Selected NVAP data sets, including animations of daily averaged global fields; monthly averaged data and sample months of daily averaged fields are available  on CD-ROM. Send an e-mail to gewex"at"gewex.org  for a copy of the NVAP CD-ROM.

The NVAP data set has been expanded to cover the 12-year period of 1988-1999 and is also available

Raman Lidar water vapor profiles from Coffeville Kansas Experiment (November - December 1991) are available on tape via the Langley DAAC.

The NVAP data set consists of global grids of 1 x 1 degree resolution, 4-layer with daily, pentad and monthly averages. The data set spans 12 years, now covers the period 1988 - 1999 and can be ordered free of charge from the site shown below.

STC-Metsat is currently completing production of NVAP-Next Generation for 2000 and 2001. NVAP-NG will merge retrievals and products from low-earth orbiting satellite platforms and create a global, twice-daily, ½ degree resolution, 5 layers water vapor product for the years 2000 and 2001. Input data includes three SSM/I's, ATOVS, TOVS, and new instruments that weren't used for NVAP, which are the Advanced Microwave Sounding Unit-B (AMSU-B), Special Sensor Microwave/Temperature-2 (SSM/T-2) as well as the Tropical Rainfall Measuring Mission Microwave Imager (TMI). The dataset will be completed by late summer, 2003.