Report on Modeling the Effects of Sea Level Rise on Coastal Wetlands

This report details the Sea Level Affecting Marshes Model (SLAMM) applied by the Massachusetts Office of Coastal Zone Management (CZM).

Tidal marshes (i.e., salt marsh and freshwater and brackish marshes influenced by tides) rely on their ability to accumulate sediment and organic matter to build elevation. If sea level rises faster than a marsh can build elevation, it will eventually drown, becoming mud flat or open water. To examine this issue, CZM—in partnership with the Woods Hole Group, Marine Biological Laboratory, Massachusetts Department of Fish and Game’s Division of Ecological Restoration, and Massachusetts Department of Environmental Protection—applied the Sea Level Affecting Marshes Model (or SLAMM) for the entire coast of Massachusetts. Modeling the Effects of Sea Level Rise on Coastal Wetlands is a report that details the SLAMM modeling approach, identifies data gaps and limitations, summarizes results at multiple scales, and provides recommendations for improved simulations. Links to the report and additional information are provided below.

Links to Report and Additional Information

For links to this report and additional information from CZM, see:

  • Modeling the Effects of Sea Level Rise on Coastal Wetlands (PDF, 20 MB) - The report was prepared for CZM in 2016 by Woods Hole Group with technical support from CZM, Marine Biological Laboratory, and other partners.
  • SLAMM Viewer (under development) - This interactive, web-based map depicts the results of this project  and the areal extent and distribution of coastal wetlands in Massachusetts as they respond to four different sea level rise scenarios over time.
  • Marsh Migration Corridors (under development) - CZM is in the process of identifying and characterizing marsh migration corridors throughout Massachusetts. These corridors are areas adjacent to the marsh or wetlands other than salt marshes that have the potential to convert to salt marsh as sea level rises.

For other sources of information on SLAMM and the impacts of sea level rise on tidal marshes, see:

  • Sea Level Affecting Marshes Model (SLAMM) ­- This website is offered by Warren Pinnacle Consulting, Inc., the developers of SLAMM. It includes information on SLAMM development, implementation, and case studies, as well as downloads for the stand-alone application.
  • Marsh Equilibrium Model (MEM) - This website of the Baruch Institute of Marine and Coastal Science, University of South Carolina, provides an online version of MEM 3.4. MEM is a salt marsh model developed by James Morris and used for this project to provide inputs on accretion (a component of surface elevation change) for SLAMM. It was applied for the Great Marsh/Upper North Shore project area only, which also received the statewide accretion input in the statewide application of SLAMM (i.e., historical sea level trend per NOAA tide station). MEM 5.41, a desktop application, was used to develop data for this project.
  • Global Sea Level Rise Scenarios for the United States National Climate Assessment (PDF, 6 MB) - This publication was developed by Parris et al. in 2012 to support the US National Climate Assessment. The four sea level rise scenarios used in the Massachusetts SLAMM project correspond to the global scenarios presented here, adapted for local conditions.