Low Marsh Change Raster for Delaware Bay Under Sea Level Rise

A 5-meter-resolution raster GIS dataset from the U.S. Environmental Protection Agency models low marsh change in the Lower Delaware Bay under an intermediate sea level rise scenario. It depicts areas of marsh gain, loss, and no change using cell values of 1, -1, and 0, respectively. The analysis utilizes recent, high-resolution elevation data and site-specific accretion records.

Use Cases

• Map low marsh loss (cell value -1) and gain (cell value 1) to quantify wetland vulnerability in the Lower Delaware Bay.
• Analyze spatial patterns of low marsh change using the 5-meter-resolution raster grid for coastal management planning.
• Compare modeled low marsh persistence (cell value 0) against other SLAMM land cover categories to assess ecosystem resilience.
• Integrate the gain/loss raster with other site-specific data, such as accretion rates, to validate sea level rise impact models.

Strengths

• Provides 5-meter spatial resolution for detailed analysis of wetland changes.
• Based on recent and high-resolution 2015 USGS CoNED Topobathy elevation data.
• Derived from SLAMM simulations incorporating site-specific accretion data through 2016.
• Part of a larger U.S. EPA project on frameworks for characterizing relative wetland vulnerabilities.

Limitations

• The dataset is specific to a single intermediate sea level rise scenario and a 'Protect Developed Dry Land' model protection scenario.
• No explicit row or column count, file size, or sample data is provided to assess the dataset's scale.
• Focus is limited to low marsh (SLAMM category 8) within the St. Jones, DE area of the Lower Delaware Bay.

Provenance

Source

U.S. Environmental Protection Agency, Office of Research and Development, National Center for Environmental Assessment.

Collection Method

Generated from SLAMM simulation outputs using the ArcGIS Raster Calculator tool to subtract baseline from future year rasters for low marsh.

Time Range

null

Freshness

Last updated on February 25, 2025.

Geography

Lower Delaware Bay, specifically the St. Jones, DE area.