VNP21: VIIRS Land Surface Temperature and Emissivity Swath Data

NASA/NOAA's Suomi NPP VIIRS Land Surface Temperature and Emissivity (LST&E) Version 2 swath product (VNP21) provides daily, 6-minute snapshots of land surface temperature and emissivity at a 750-meter spatial resolution. The dataset is generated using a physics-based algorithm that simultaneously retrieves LST and emissivity for three thermal infrared bands, employing the ASTER Temperature Emissivity Separation technique with an improved Water Vapor Scaling atmospheric correction. It is designed for continuity with MODIS Terra and Aqua products and includes layers for quality control, emissivity, errors, view angle, precipitable water vapor, and geolocation.

Use Cases

• Monitoring urban heat islands based on high-resolution (750m) land surface temperature (LST) data.
• Improving land surface models by incorporating dynamic emissivity values for VIIRS bands M14, M15, and M16.
• Analyzing diurnal temperature cycles using the daily, 6-minute temporal increments of satellite acquisition.
• Assessing atmospheric correction methods by utilizing the provided Precipitable Water Vapor (PWV) and quality control layers.
• Conducting cross-sensor validation studies by comparing VNP21 data with the synergistic MODIS MOD21 product.

Strengths

• Provides a high temporal resolution product, generated daily in 6-minute increments.
• Offers a specific spatial resolution of 750 meters for detailed land surface analysis.
• Uses a sophisticated, physics-based algorithm (TES with WVS) for simultaneous retrieval of LST and emissivity.
• Ensures continuity with the long-term MODIS Terra and Aqua mission data record.

Limitations

• Metadata completeness is low; specific column names, row counts, and file sizes are not provided on any platform.
• Contains a known issue of increased extreme high temperature outliers, especially over desert regions, compared to heritage products.
• The license is ambiguously listed as 'other-license-specified' without explicit terms.

Provenance

Source

National Aeronautics and Space Administration (NASA)

Collection Method

Satellite remote sensing data from the Suomi NPP spacecraft's VIIRS instrument, processed with a physics-based retrieval algorithm.

Time Range

Daily production from the Suomi NPP mission start date (not specified) onward.

Freshness

2026-03-12 20:11:35.369816

Geography

Global swath coverage from the polar-orbiting satellite.