Solar radiation enters the Earth's atmosphere with a portion being scattered by clouds and aerosols.

Processing, archiving and distributing Earth science data
at the NASA Langley Research Center

NVAP-M Data and Information

NVAP-M Data and Information

Improvement of the NVAP Global Water Vapor Data Set for Climate, Hydrological and Weather Studies

 

Principal Investigator: Thomas Vonder Haar, Science and Technology Corp.

 

The NASA MEaSUREs program began in 2008 and has the goal of creating stable, community accepted Earth System Data Records (ESDRs) for a variety of geophysical time series. A reanalysis and extension of the NASA Water Vapor Project (NVAP), called NVAP-M was performed by Science and Technology Corporation, METSAT Division as part of this program. NVAP-M spans 1988-2009. NVAP-M is further described in Vonder Haar, T. H., J. L. Bytheway and J. M. Forsythe, 2012: "Weather and climate analyses using improved global water vapor observations." Geophys. Res. Lett.39, L16802, doi:10.1029/2012GL052094

 

The heritage NASA Water Vapor Project (NVAP) total column (integrated) water vapor data sets comprised a combination of radiosonde observations, Television and Infrared Operational Satellite (TIROS) Operational Vertical Sounders (TOVS), and Special Sensor Microwave/Imager (SSM/I) data sets. These data sets spanned 14 years (1988 - 2001) and contained total and layered global water vapor data. The spatial coverage was global for all data sets. NVAP-M completely supercedes the heritage NVAP data set.

Uses consistent input data and algorithms through time at the expense of spatial and temporal resolution. Intended for studies of interannual variability and climate.
Products Temporal Resolution Spatial Resolution Temporal Coverage
CLIMATE_Layered-Precipitable-Water

Contains Vertical Structure Information

Daily

1988 - 2009

CLIMATE_Total-Precipitable-Water

Contains Vertical Structure Information

Daily

1988 - 2009

Higher spatial and temporal resolution. Land GPS sites added beginning in 1997. Intended for weather case studies.
Products Temporal Resolution Spatial Resolution Temporal Coverage
WEATHER_Layered-Precipitable-Water

Contains Vertical Structure Information

6-hourly (4 times a day)

0.5°

1988 - 2009

WEATHER_Total-Precipitable-Water

Contains Vertical Structure Information

6-hourly (4 times a day)

0.5°

1988 - 2009

Similar to NVAP-M Climate, but using only SSM/I data inputs. Intended for comparison to similar ocean-only passive microwave water vapor datasets.
Products Temporal Resolution Spatial Resolution Temporal Coverage
OCEAN_Total-Precipitable-Water

Daily

1988 - 2009

NVAP-M read software is product dependent. If read software is available, a "read software" tab will appear on the product landing page.