THIRN7IM: Nimbus-7 Infrared Brightness Temperature Montages

Daily montages from the Nimbus-7 THIR instrument contain up to 14 individual swaths of brightness temperature data measured at 6.7 and 11.5 microns. The instrument operated from October 30, 1978 to May 9, 1985, providing global coverage with a ground resolution of 22.6 km for the 6.7-micron channel and 8.2 km for the 11.5-micron channel at nadir. These data were designed to detect thermal radiation for mapping cloud-top temperatures and upper-tropospheric water vapor distribution.

Use Cases

• Analyzing historical cloud-top temperature patterns based on the 11.5-micron window channel data.
• Mapping the distribution of water vapor in the upper troposphere and stratosphere using the 6.7-micron channel night-time observations.
• Studying the diurnal cycle of atmospheric phenomena by comparing daytime and nighttime montage assemblies.
• Calibrating or validating climate models with historical infrared brightness temperature records from a defined period.

Strengths

• Provides a continuous, multi-year record from a specific operational period (Oct 30, 1978 to May 9, 1985).
• Offers dual-channel infrared measurements with documented, instrument-specific ground resolutions (6.7 µm at 22.6 km, 11.5 µm at 8.2 km at nadir).
• Dataset is documented by official user guides ('The Nimbus 7 User's Guide' and the 'THIR Data User's Guide').

Limitations

• Key metadata such as row count, file size, and specific column structure is unavailable across all sources.
• There is a conflict in reported 'last updated' dates between platforms (1985 vs. 2026), creating uncertainty about metadata maintenance.
• The data's spatial resolution decreases with horizontal distance from the subsatellite track, which may limit analysis for some applications.

Provenance

Source

National Aeronautics and Space Administration (NASA)

Collection Method

Collected by the Temperature-Humidity Infrared Radiometer (THIR) instrument aboard the Nimbus-7 satellite.

Time Range

1978-10-30 to 1985-05-09

Freshness

2026-04-09 21:45:22.692421

Geography

Global