Alaska Digital Terrain Elevation Slope And Aspect Mosaics

Digital elevation data for Alaska includes nine types of terrain mosaics such as elevation, slope, aspect, and shaded relief. The dataset contains 966 records derived from 1:250,000 scale Defense Mapping Agency Digital Terrain Series, with data coverage from 1982 to present. It is maintained by the USGS and organized by 7.5' or 15' quadrangle units.

Use Cases

• Land cover analysis using 1-degree x 3-degree mosaics of elevation and slope.
• Drainage and watershed analysis leveraging filtered elevation data from the 5x5 filter mosaic.
• Wildlife habitat studies utilizing aspect mosaics in both latitude/longitude and UTM coordinate systems.
• Land use planning and visualization with shaded relief mosaics for terrain representation.

Strengths

• 966 distinct terrain data records provide multiple analysis layers.
• Data coverage spans from 1982 to present, offering a multi-decade temporal range.
• Includes nine specific data products like elevation, slope, aspect, and shaded relief mosaics.

Limitations

• Data is derived from 1:250,000 scale source maps, which may limit fine-detail resolution.
• Estimated growth of only 5-15 records per year indicates slow updates.
• Original data delivery formats are outdated (9-track tape, BCD tape).

Provenance

Source

Defense Mapping Agency Digital Terrain Series.

Collection Method

Processed into 1-degree x 3-degree mosaics from source topographic maps.

Time Range

1982 to present

Freshness

Data coverage is from 1982 to present with ongoing updates.

Geography

Alaska, United States