Tidal marshes are susceptible to climate change, especially sea level rise (SLR). Changes in tidal marsh area and habitat type
may be estimated using the SLAMM model. This simulates the dominant processes involved in wetland conversion and shoreline
modification under different scenarios of sea level rise: inundation (based on elevation and slope), erosion (based on threshold
of maximum fetch and proximity to tidal water), accretion (sea level rise is offset by sedimentation and vertical accretion),
soil saturation (sea level rise affects the fresh water table) and barrier island overwash (for islands under 500m width). SLAMM
tracks the rise of water levels and the salt boundary in 25-year time steps and predicts changes to wetland habitat based on
known relationships between wetland types and tide ranges. The model was run using "protection off", thereby depicting the potential
for marsh migration into upland areas despite limitations of current land use or development. The connectivity sub-model was run
for both options, "on" requires a low-elevation pathway to saline water, and "off" does not require a flow pathway to saline water.
SLR1M_2025_C: Potential change in salt marsh at 1.2 meter SLR for year 2025 (intermediate-high emissions scenario), with connectivity on
SLR1M_2100_C: Potential change in salt marsh at 1.2 meter SLR for year 2100 (intermediate-high emissions scenario), with connectivity on
SLR2M_2025_C: Potential change in salt marsh at 2 meter SLR for year 2025 (high emissions scenario), with connectivity on
SLR2M_2100_C: Potential change in salt marsh at 2 meter SLR for year 2100 (high emissions scenario), with connectivity on