Lake Michigan Bathymetry from 120 Years of Soundings

NOAA compiled bathymetric data for Lake Michigan using over 600,000 hydrographic soundings collected over a 120-year period. The compilation reveals lake floor physiography at a 1:250,000 scale with a 5-meter contour interval. This cooperative project between NGDC/MGG and GLERL digitized historical data to create an accessible map of the lakebed.

Use Cases

• Analyze lake floor physiography using the 5-meter contour interval data to identify underwater features.
• Model sediment transport and erosion patterns by studying bathymetric contours derived from over 600,000 soundings.
• Create digital elevation models (DEMs) of the lakebed from the vectorized contour data compiled at 1:250,000 scale.
• Assess nearshore bathymetry changes by comparing data from tracklines with 200m to 600m density.

Strengths

• Integrates over 600,000 bathymetric soundings for comprehensive coverage.
• Data spans a 120-year collection period, providing historical depth.
• Compilation scale of 1:250,000 with a 5-meter contour interval offers detailed resolution.
• Nearshore trackline density ranges from 200m to 600m, enhancing coastal detail.

Limitations

• Approximately 15% of the original soundings were available only on paper, potentially introducing digitization errors.
• The open lake trackline density is generally about 2000m, which may result in lower resolution for deep-water areas compared to nearshore zones.
• Soundings prior to 1903 required datum reduction, which may introduce minor inconsistencies compared to post-1903 data.

Provenance

Source

National Oceanic and Atmospheric Administration, Department of Commerce

Collection Method

Compiled from historical hydrographic soundings collected by NOAA National Ocean Service and the U.S. Army Corps of Engineers; data digitized, contoured, and vectorized.

Time Range

Soundings collected over a 120-year period (specific start year not stated, includes data from before 1903).

Freshness

Last updated in October 2024.

Geography

Lake Michigan, Great Lakes region, United States.