SSDF: CONUS Vapor Pressure Deficit from AIRS and CrIMSS Satellites

NASA's Spatial Statistical Data Fusion (SSDF) Level 3 dataset provides daily estimates of near-surface vapor pressure deficit over the continental United States. The product fuses data from the AIRS instrument on Aqua and the CrIMSS suite on Suomi-NPP, using a statistical algorithm that weights inputs by their estimated variance. It provides these estimates on a consistent ¼-degree latitude/longitude grid.

Use Cases

• Monitoring drought stress and atmospheric aridity for agricultural planning based on daily vapor pressure deficit estimates.
• Validating and calibrating land surface or hydrological models using a spatially fused, bias-corrected satellite product.
• Analyzing spatial patterns and temporal trends in water vapor indicators across the continental United States.
• Studying the fusion methodology of multi-instrument satellite data for atmospheric state estimation.

Strengths

• Data fusion from two major satellite instrument suites (AIRS and CrIMSS) likely improves spatial coverage and reliability.
• Algorithm employs bias correction and variance weighting, which suggests a formal statistical rigor in merging datasets.
• Provides daily data on a consistent ¼-degree grid, enabling time-series analysis over the CONUS region.

Limitations

• Column names and exact data structure are not specified in any source, limiting immediate usability.
• Conflicting 'last updated' dates (2026 vs. 2020) create uncertainty about dataset freshness and maintenance.
• Spatial coverage is limited to the continental United States (CONUS), excluding other regions.

Provenance

Source

National Aeronautics and Space Administration (NASA)

Collection Method

Spatial statistical fusion of Level-2 satellite retrievals from the AIRS (Aqua) and CrIMSS (Suomi-NPP) instruments, matched to in-situ data for bias and variance characterization.

Freshness

2026-04-09 20:28:41.021591 (from datagov, but conflicts with nasa_earthdata date of 2020-12-31)

Geography

Continental United States (CONUS) on a ¼ x ¼ degree latitude/longitude grid.