Nimbus-7 Microwave Brightness Temperatures 1978-1987

October 1978 to August 1987 brightness temperature data from the Nimbus-7 Scanning Multichannel Microwave Radiometer (SMMR). This Level 1B dataset provides near-global swath measurements at five frequencies and dual polarizations, collected every six days. The Jet Propulsion Laboratory processed the data into daily orbit files totaling approximately 70 gigabytes.

Use Cases

• Analyzing long-term trends in sea ice concentration using 18 and 37 GHz channels.
• Retrieving historical soil moisture or atmospheric water vapor content from brightness temperature measurements.
• Calibrating or validating newer satellite microwave radiometers against this foundational dataset.
• Studying the temporal evolution of polar regions with near-global coverage every six days.
• Developing algorithms for geophysical parameter retrieval from multi-frequency, dual-polarization microwave data.

Strengths

• Provides a continuous, near-global record from October 1978 to at least August 1987, a critical period for climate baseline studies.
• Contains measurements at five specific frequencies (6.6, 10.7, 18, 21, 37 GHz) in both horizontal and vertical polarizations.
• Data volume of approximately 70 GB indicates a substantial observational record stored in a structured HDF format.

Limitations

• Sources conflict on the operational end date: one states 20 August 1987, another states 16 November 1987 with alternate-day operation beginning afterward.
• Specific column names and the exact row/orbit count are not provided in the available metadata.
• Data is stored in legacy HDF format, which may require specific libraries for access and processing.

Provenance

Source

Jet Propulsion Laboratory (JPL), processed from Level 1A data provided by Goddard Space Flight Center (GFSC).

Collection Method

Collected by the Nimbus-7 satellite's Scanning Multichannel Microwave Radiometer (SMMR) instrument at a constant 50.3-degree incidence angle.

Time Range

1978-10-25 to 1987-08 20 (with a noted conflict extending to 1987-11-16).

Freshness

2026-03-12 23:19:06.298441

Geography

Near-global coverage.