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NVAP-M
NASA Water Vapor Project (NVAP) - MEaSUREs
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.
Program Background and Goal
The NASA MEaSUREs program began in 2008 with the goal of creating stable, community-accepted Earth System Data Records (ESDRs) for a variety of geophysical time series.
NVAP-M Overview
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.
- Time Span: 1988–2009
- Supersedure: NVAP-M completely supersedes the heritage NVAP dataset
STC-METSAT Product Description
STC-METSAT (a division of Science and Technology Corporation) produced a blended analysis of global water vapor under a NASA-sponsored research grant. This product combines retrievals of precipitable water (or water vapor) from:
- Ground-based radiosondes
- Microwave frequencies from the Special Sensor Microwave/Imager (SSM/I)
- Infrared TOVS observations from the NOAA operational series of satellites
NVAP Heritage Dataset Composition and Coverage
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)
- Special Sensor Microwave/Imager (SSM/I) data sets
These datasets:
- Time Span: 14 years (1988–2001)
- Content: Contained total and layered global water vapor data
- Spatial Coverage: Global
Dataset Resolution and Averages
The NVAP dataset consists of:
- Resolution: Global grids of 1x1 degree resolution
- Averages: Daily, pentad, and monthly averages
- Time Span: Spans 5 years from 1988–1992
Principal Investigator
Vonder Haar, T. H.
Data Centers
ASDC