BOREAS DSP-04: Radar-Derived Landscape Freeze/Thaw Maps

ERS-1 radar data from 1994 captured over a full annual cycle in Canada's BOREAS sites reveals two distinct environmental transitions: snow melt/soil thaw onset and potential canopy thaw. These gridded maps, derived from backscatter change detection, demonstrate radar's ability to observe thaw transitions at the start of the growing season. The data constrains growing season length by providing a landscape-scale freeze/thaw classification.

Use Cases

• Monitoring seasonal thaw onset and growing season length based on radar backscatter transitions.
• Validating climate and ecosystem models using gridded landscape freeze/thaw state maps.
• Analyzing the relationship between snow melt, soil thaw, and canopy processes from co-registered radar imagery.

Strengths

• Data covers a complete annual cycle from 1994, enabling analysis of full seasonal transitions.
• Provides dual-format outputs (ASCII text and GIF images) for both analytical and visualization purposes.
• Derived from ESA's ERS-1 satellite, a recognized source for historical radar remote sensing.

Limitations

• Metadata conflict: last updated date is reported as both 1994-12-14 and 2026-03-13, creating uncertainty about provenance.
• Key technical details like spatial resolution, grid size, and specific column names are not provided in the available metadata.
• Limited to a single year (1994) and the southern BOREAS sites, reducing temporal and spatial generalizability.

Provenance

Source

National Aeronautics and Space Administration (NASA), BOREAS DSP-4 team.

Collection Method

Imaging radar data from ESA's ERS-1 satellite, processed through change detection thresholding relative to a winter frozen reference state.

Time Range

1994

Freshness

2026-03-13 (from datagov, but conflicts with 1994 date from nasa_earthdata)

Geography

BOREAS sites in Canada (specifically southern sites).