VNP21A2: Land Surface Temperature and Emissivity 8-Day Composite

NASA/NOAA's VNP21A2 dataset is an 8-day composite Land Surface Temperature and Emissivity (LST&E) product derived from the Suomi NPP VIIRS sensor. It provides global coverage at a 1-kilometer spatial resolution, combining daytime and nighttime acquisitions into a single HDF file. The product is algorithmically compatible with MODIS data to ensure continuity in Earth observation records.

Use Cases

• Monitoring urban heat island effects using 1km resolution temperature layers.
• Analyzing seasonal land surface temperature trends from 8-day composite time series.
• Validating climate and weather models with satellite-derived emissivity data.
• Studying diurnal temperature cycles using separate daytime and nighttime science dataset layers.

Strengths

• Provides continuity with the established MODIS LST&E product line, using the same algorithmic approach.
• Offers both daytime and nighttime land surface temperature measurements within a single composite product.
• Has a defined spatial resolution of 1 kilometer for global coverage.

Limitations

• The described VNP21A2 Version 1 product was officially decommissioned on April 8, 2025, limiting its use for current analysis.
• Key metadata such as row count, file size, and specific column names are not provided across any source.
• The last update dates conflict between platforms (2024 vs. 2026), creating uncertainty about metadata maintenance.

Provenance

Source

National Aeronautics and Space Administration (NASA)

Collection Method

Satellite remote sensing data from the Suomi NPP Visible Infrared Imaging Radiometer Suite (VIIRS), processed using a simple-averaging algorithm on cloud-free daily acquisitions.

Freshness

Last updated dates conflict: one source shows 2024-04-29, another shows 2026-04-09.

Geography

Global