20250924
16262900
1.0
FALSE
VA_MarshMigrationCorridors_2ft_2024_2026
002
Projected
GCS_North_American_1983
Linear Unit: Meter (1.000000)
NAD_1983_UTM_Zone_18N
<ProjectedCoordinateSystem xsi:type='typens:ProjectedCoordinateSystem' xmlns:xsi='http://www.w3.org/2001/XMLSchema-instance' xmlns:xs='http://www.w3.org/2001/XMLSchema' xmlns:typens='http://www.esri.com/schemas/ArcGIS/3.5.0'><WKT>PROJCS["NAD_1983_UTM_Zone_18N",GEOGCS["GCS_North_American_1983",DATUM["D_North_American_1983",SPHEROID["GRS_1980",6378137.0,298.257222101]],PRIMEM["Greenwich",0.0],UNIT["Degree",0.0174532925199433]],PROJECTION["Transverse_Mercator"],PARAMETER["False_Easting",500000.0],PARAMETER["False_Northing",0.0],PARAMETER["Central_Meridian",-75.0],PARAMETER["Scale_Factor",0.9996],PARAMETER["Latitude_Of_Origin",0.0],UNIT["Meter",1.0],AUTHORITY["EPSG",26918]]</WKT><XOrigin>-5120900</XOrigin><YOrigin>-9998100</YOrigin><XYScale>450445547.3910538</XYScale><ZOrigin>-100000</ZOrigin><ZScale>10000</ZScale><MOrigin>-100000</MOrigin><MScale>10000</MScale><XYTolerance>0.001</XYTolerance><ZTolerance>0.001</ZTolerance><MTolerance>0.001</MTolerance><HighPrecision>true</HighPrecision><WKID>26918</WKID><LatestWKID>26918</LatestWKID></ProjectedCoordinateSystem>
20250922
20574200
20250924
15492500
150000000
5000
ISO19115_3
Esri ArcGIS 13.5.3.57366
Marsh Migration Corridors - 2 ft rise 2024-2026
Center for Coastal Resources Management
Virginia Institute of Marine Science
kirk@vims.edu
This layer shows where marsh is predicted to migrate after a 2 foot sea level rise in select Virginia localities. This will allow planners and policy makers to target these areas for conservation efforts.
<DIV STYLE="text-align:Left;"><DIV><DIV><P><SPAN>There are four marsh migration models incorporated into this layer. NOAA generated raster data layers using three models (SLAMM, InVEST, NOAA). This raster showed where marsh migration was predicted to occur for a water level rise of two feet according to each of these three models. The Evolution of Tidal Marsh (ETM) marsh migration model which VIMS produced was then overlaid on top of this. The ETM rasters represent successive tidal ranges of two feet of elevation, incremented by 0.5 feet, i.e. 0-2 ft, 0.5-2.5 ft, 1-3 ft, etc.). From the ETM analysis, the tidal range layer was used which had a 2 foot water rise as a midpoint in the tidal range. The raster from ETM was overlaid on the raster from the NOAA analysis. Raster cells were classified by the number of models overlaid on a given cell. Cells overlaid by all four models were given a score of 4, cells overlaid by three models were given a score of 3, cells overlaid by two models were given a score of 2, and cells overlaid by one model were given a score of 1. This data layer was then clipped to locality boundarys. In this analysis, developed lands (Developed, Medium Intensity and Developed, High Intensity categories from the National Land Cover Dataset) were considered to be unsuitable for future marsh migration and were excluded from the final output.</SPAN></P><P><SPAN>A series of post-processing steps were taken to eliminate stray isolated raster cells and the raster was converted to polygons. Only marsh clusters which intersected tidal marsh (CCRM Tidal Marsh Inventory) and nontidal wetlands adjacent to it were extracted for the final output. The polygons were processed through the Smooth Polygon tool in ArcGIS Pro to improve appearance while retaining spatial integrity.</SPAN></P></DIV></DIV></DIV>
Marsh Migration Corridor Envelope for Maryland and Virginia (https://hub.arcgis.com/documents/ChesBay::marsh-migration-corridor-envelope-for-maryland-and-virginia/about, October 2023) Migration of the Tidal Marsh Range Under Sea Level Rise for Coastal Virginia, with Land Cover Data (https://scholarworks.wm.edu/data/444/, Mitchell and Herman, July 2021)
https://www.vims.edu/ccrm/research/inventory/
https://www.fws.gov/program/national-wetlands-inventory
sea level rise marsh migration model
Virginia
Daniel Schatt
Virginia Institute of Marine Science
GIS Analyst/Programmer
dschatt@vims.edu
P.O. Box 1346
Gloucester Point
Virginia
23602
US
804-684-7536
Daniel Schatt
Daniel Schatt
Karinna Nunez
Virginia Institute of Marine Science
Geospatial Modeling Manager
P.O. Box 1346
Gloucester Point
Virginia
23052
US
804-684-7273
Karinna Nunez
1
-76.46
-76.23
37.3
37.54
Chesapeake Bay, Virginia, Gloucester, Hampton, Lancaster, Mathews, Middlesex, Northumberland, Poquoson, Virginia Beach, Westmoreland, York
File Geodatabase Feature Class
dataset
EPSG
6.11(3.0.1)
0
Simple
FALSE
0
TRUE
FALSE
Gloucester_Final_2ft
Feature Class
0
Gloucester_Final_2ft
Gloucester_Final_2ft
OBJECTID
OBJECTID
OID
4
0
0
Internal feature number.
Esri
Sequential unique whole numbers that are automatically generated.
Shape
Shape
Geometry
0
0
0
Feature geometry.
Esri
Coordinates defining the features.
Id
Id
Integer
4
0
0
gridcode
gridcode
Integer
4
0
0
This is the number of migration models predicting marsh in a given polygon.
Gloucester_Final_2ft
1
4
DISSOLVE
DISSOLVE
Integer
4
0
0
InPoly_FID
InPoly_FID
Integer
4
0
0
ModelAgreement
ModelAgreement
String
255
0
0
This field gives the definition for the value in the gridcode field.
Center for Coastal Resources Management (CCRM)
Locality
Locality
String
255
0
0
County/City that the feature layer is located in.
CCRM
PubYear
PubYear
String
4
0
0
Year in which data was published
CCRM
Shape_Length
Shape_Length
Double
8
0
0
Length of feature in internal units.
Esri
Positive real numbers that are automatically generated.
Shape_Area
Shape_Area
Double
8
0
0
Area of feature in internal units squared.
Esri
Positive real numbers that are automatically generated.
20250924
Daniel Schatt
Virginia Institute of Marine Science
GIS Analyst/Programmer
dschatt@vims.edu
P.O. Box 1346
Gloucester Point
Virginia
23602
US
804-684-7536
Daniel Schatt
Daniel Schatt
There are four marsh migration models incorporated into this layer. NOAA generated raster data layers using three models (SLAMM, InVEST, NOAA). This raster showed where marsh migration was predicted to occur for a water level rise of two feet according to each of these three models. The Evolution of Tidal Marsh (ETM) marsh migration model which VIMS produced was then overlaid on top of this. The ETM rasters represent successive tidal ranges of two feet of elevation, incremented by 0.5 feet, i.e. 0-2 ft, 0.5-2.5 ft, 1-3 ft, etc.). From the ETM analysis, the tidal range layer was used which had a 2 foot water rise as a midpoint in the tidal range. The raster from ETM was overlaid on the raster from the NOAA analysis. Raster cells were classified by the number of models overlaid on a given cell. Cells overlaid by all four models were given a score of 4, cells overlaid by three models were given a score of 3, cells overlaid by two models were given a score of 2, and cells overlaid by one model were given a score of 1. This data layer was then clipped to locality boundarys. In this analysis, developed lands (Developed, Medium Intensity and Developed, High Intensity categories from the National Land Cover Dataset) were considered to be unsuitable for future marsh migration and were excluded from the final output.
A series of post-processing steps were taken to eliminate stray isolated raster cells and the raster was converted to polygons. Only marsh clusters which intersected tidal marsh (CCRM Tidal Marsh Inventory) and nontidal wetlands adjacent to it were extracted for the final output. The polygons were processed through the Smooth Polygon tool in ArcGIS Pro to improve appearance while retaining spatial integrity.
Processed localities were appended to form one dataset.
Marsh Migration Corridor Envelope for Maryland and Virginia (https://hub.arcgis.com/documents/ChesBay::marsh-migration-corridor-envelope-for-maryland-and-virginia/about, October 2023) Migration of the Tidal Marsh Range Under Sea Level Rise for Coastal Virginia, with Land Cover Data (https://scholarworks.wm.edu/data/444/, Mitchell and Herman, July 2021)
https://www.vims.edu/ccrm/research/inventory/
https://www.fws.gov/program/national-wetlands-inventory