SCAMSN6IM: Nimbus-6 Microwave Images of Atmospheric Temperature and Water Vapor

SCAMSN6IM data consists of scanned TIFF images from the Nimbus-6 Scanning Microwave Spectrometer (SCAMS), showing eight vertical strips of data per orbit. The strips represent brightness temperatures at 31.65 GHz and 52.85 GHz, retrieved water vapor, liquid water over oceans, and inverted mean temperatures for three atmospheric pressure layers. Spatial resolution on the ground varies from 145 km at nadir to 330 km at the scan extremes.

Use Cases

• Analyzing historical atmospheric temperature profiles for layers 1000-500, 500-250, and 250-100 mbar based on inverted mean temperature strips.
• Estimating water vapor and cloud liquid water content over calm oceans using the dedicated 10 mm wavelength channels.
• Studying brightness temperature differences between 31.65 GHz and 52.85 GHz channels for microwave emission analysis.
• Examining geographic patterns of atmospheric parameters, as all eight strips share the same geographic coverage per orbit.

Strengths

• Provides multi-parameter data from a single instrument, with eight distinct atmospheric measurements per orbital image.
• Offers a historical record from the Nimbus-6 mission, a follow-on to the successful Nimbus-5 NEMS experiment.
• Includes detailed technical specifications, such as scan range (+/- 45 degrees), field of view (10 degrees), and five specific frequency channels (22.235 to 55.45 GHz).

Limitations

• Data is provided as scanned film strip images (TIFFs), not as numerical arrays, requiring digitization or visual interpretation.
• Key metadata is missing or conflicting: row count, file size, and author are unknown; the last updated date conflicts between 1976-05-31 (nasa_earthdata) and 2026-04-09 (datagov).
• Spatial resolution is coarse, varying from 145 km to 330 km, limiting fine-scale analysis.

Provenance

Source

National Aeronautics and Space Administration

Collection Method

Data gathered by the Nimbus-6 Scanning Microwave Spectrometer (SCAMS), a Dicke-superheterodyne type instrument scanning +/- 45 degrees normal to the orbital plane.

Time Range

1976 (based on the end date from nasa_earthdata); specific start date is not provided.

Freshness

2026-04-09 22:30:32.828788 (from datagov, though this appears to be a future date and conflicts with the 1976 date from nasa_earthdata).

Geography

Global coverage from Nimbus-6 satellite orbits.