Geospatial data in support of structured decision making for Fire Island National Seashore, New York

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Frequently anticipated questions:

What does this data set describe?

Title:
Geospatial data in support of structured decision making for Fire Island National Seashore, New York
Abstract:
Salt marshes provide a range of ecosystem services, including storm protection, recreation, and commercial fishery habitat provision. The National Park Service (NPS) aims to preserve and protect salt marshes in order to achieve multiple objectives which address their mission: to preserve unimpaired the natural and cultural resources and values of their publicly held lands. Ongoing threats, including sea-level rise, sediment deficits, invasive species, and anthropogenic pressure have led to substantial salt marsh loss in the northeast US over the last century prompting increased investment in their protection and restoration. Here we describe a structured decision making (SDM) framework involving eight NPS units designed to help guide restoration planning and investment, through identification of priority marshes. The framework was developed first through a facilitated workshop with all units, followed by unit-specific workshops where priorities were adjusted to reflect the natural and cultural resources within the unit. The final product is a series of maps depicting performance metrics over a consistent geospatial framework. Integration of these metrics into decision support tools will help guide marsh restoration investments through identification of marsh units and complexes that maximize agency priorities and objectives. This dataset represents the regional and unit-specific metrics generated for Fire Island National Seashore (FIIS).
Supplemental_Information:
All links for cited references and data portals were valid at the time of the work, but support for these web resources may change over time.
  1. How might this data set be cited?
    Ackerman, Kate V., Andrews, Brian D., Ganju, Neil K., and Defne, Zafer, 20251211, Geospatial data in support of structured decision making for Fire Island National Seashore, New York: data release DOI:10.5066/P13E2NM2, U.S. Geological Survey, Coastal and Marine Hazards and Resources Program, Woods Hole Coastal and Marine Science Center, Woods Hole, MA.

    Online Links:

    This is part of the following larger work.

    Ackerman, Kate V., Andrews, Brian D., Ganju, Neil K., and Defne, Zafer, 2025, Geospatial data in support of structured decision making for northeast coastal parks: data release DOI:10.5066/P13E2NM2, U.S. Geological Survey, Reston, VA.

    Online Links:

    Other_Citation_Details:
    Suggested citation: Ackerman, K.V., Andrews, B.D., Ganju, N.K., and Defne, Z., 2025, Geospatial data in support of structured decision making for northeast coastal parks: U.S. Geological Survey data release, https://doi.org/10.5066/P13E2NM2.
  2. What geographic area does the data set cover?
    West_Bounding_Coordinate: -73.235222
    East_Bounding_Coordinate: -72.747393
    North_Bounding_Coordinate: 40.776584
    South_Bounding_Coordinate: 40.638028
  3. What does it look like?
    https://www.sciencebase.gov/catalog/file/get/68ac96d7d4be0263d2491100/?name=FIIS_SaltMarsh_Browse.png&allowopen=true (PNG)
    Graphic showing the FIIS salt marshes
  4. Does the data set describe conditions during a particular time period?
    Calendar_Date: 2025
    Currentness_Reference:
    publication date
  5. What is the general form of this data set?
    Geospatial_Data_Presentation_Form: vector digital data
  6. How does the data set represent geographic features?
    1. How are geographic features stored in the data set?
      This is a Vector data set. It contains the following vector data types (SDTS terminology):
      • G-polygon (240)
    2. What coordinate system is used to represent geographic features?
      The map projection used is WGS 1984 Web Mercator Auxiliary Sphere (ESRI Full Name: WGS_1984_Web_Mercator_Auxiliary_Sphere).
      Projection parameters:
      Standard_Parallel: 0.0
      Longitude_of_Central_Meridian: 0.0
      False_Easting: 0.0
      False_Northing: 0.0
      Planar coordinates are encoded using coordinate pair
      Abscissae (x-coordinates) are specified to the nearest 0.6096
      Ordinates (y-coordinates) are specified to the nearest 0.6096
      Planar coordinates are specified in Meter
      The horizontal datum used is D_WGS_1984.
      The ellipsoid used is WGS_1984.
      The semi-major axis of the ellipsoid used is 6378137.0.
      The flattening of the ellipsoid used is 1/298.25722.
  7. How does the data set describe geographic features?
    FIIS_SDM_Metrics.shp
    Attribute information associated with marsh units of Fire Island National Seashore salt marsh complex. (Source: U.S. Geological Survey)
    FID
    Internal feature number (Source: Esri) Sequential unique whole numbers that are automatically generated.
    Shape
    Feature geometry (Source: Esri) Coordinates defining the feature type.
    FID_CMU
    Sequential unique whole number that represents the identification number for each conceptual marsh unit. This attribute was carried over from the original source, mu_lifespan_NY.shp. (Source: USGS)
    Range of values
    Minimum:5117
    Maximum:6194
    Units:none
    ATOT_M2
    Total surface area of a marsh unit in square meters. This attribute was carried over from the original source, mu_lifespan_NY.shp. (Source: USGS)
    Range of values
    Minimum:424.934
    Maximum:368730.271
    Units:square meters
    AVEG_M2
    Surface area of vegetated part of a marsh unit in square meters. This attribute was carried over from the original source, mu_lifespan_NY.shp. (Source: USGS)
    Range of values
    Minimum:0
    Maximum:241648.113
    Units:square meters
    GMSL05
    Lifespan for a marsh unit (in years) for global mean sea-level rise of 0.5 m by 2100. Negative lifespan values (other than No Data) indicates the estimated lifespan is depleted and loss is imminent. A value of 10,000 indicates a lifespan equal to or greater than 10,000. A value of -9999 indicates no data. This attribute was carried over from the original source, mu_lifespan_NY.shp. (Source: USGS)
    Range of values
    Minimum:-36
    Maximum:10000
    Units:years
    GMSL10
    Lifespan for a marsh unit (in years) for global mean sea-level rise of 1.0 m by 2100. Negative lifespan values (other than No Data) indicates the estimated lifespan is depleted and loss is imminent. A value of 10,000 indicates a lifespan equal to or greater than 10,000. A value of -9999 indicates no data. This attribute was carried over from the original source, mu_lifespan_NY.shp. (Source: USGS)
    Range of values
    Minimum:-27
    Maximum:10000
    Units:years
    UVVR
    Ratio of unvegetated surface area to vegetated surface area. Ordinarily, UVVR ranges from zero (completely vegetated) to infinity (completely unvegetated). However, it is assigned the value of -1 when completely unvegetated. Note that there can be very large values of UVVR (indicating that the marsh unit is mostly unvegetated). This attribute was carried over from the original source, mu_lifespan_NY.shp. (Source: USGS)
    Range of values
    Minimum:-1
    Maximum:38.877
    Units:none
    Zstar
    Mean wetland elevation above mean sea level relative to the tidal range of the marsh unit. A value of -9999 indicates no data. (Source: USGS)
    Range of values
    Minimum:-0.343
    Maximum:3.005
    Units:unitless
    AMIG_M2
    Potential marsh migration area in square meters. (Source: USGS)
    Range of values
    Minimum:0
    Maximum:525162.727
    Units:square meters
    WavePwr
    The wave power (energy per unit length) generated by the movement of ocean waves, averaged over a marsh unit. (Source: USGS)
    Range of values
    Minimum:0
    Maximum:15.439
    Units:Watts/meter
    Wake_Norm
    Wake exposure of each marsh unit, normalized to a value between 0 and 1. (Source: USGS)
    Range of values
    Minimum:0
    Maximum:0.999
    Units:None
    NWIclass
    Number of NWI subclasses in a marsh unit. (Source: USGS)
    Range of values
    Minimum:1
    Maximum:3
    Units:None
    Ditchkmkm2
    Ditching intensity (linear kilometers of ditch per square kilometer of marsh unit area). (Source: USGS)
    Range of values
    Minimum:0
    Maximum:38.935
    Units:kilometers per square kilometer
    SALS_P
    Presence (1) or absence (0) of priority Saltmarsh Sparrow (SALS) habitat within a marsh unit. (Source: USGS)
    ValueDefinition
    1Presence of priority Saltmarsh Sparrow (SALS) habitat within a marsh unit.
    0Absence of priority Saltmarsh Sparrow (SALS) habitat within a marsh unit.
    SAV
    Presence (1) or absence (0) of submerged aquatic vegetation (SAV) within 100m of a marsh unit. (Source: USGS)
    ValueDefinition
    1Presence of SAV within 100m of a marsh unit.
    0Absence of SAV within 100m of a marsh unit.
    BioDiv
    The sum of attributes SALS_P and SAV to indicate whether a marsh unit has priority Saltmarsh Sparrow habitat within the marsh unit, or SAV adjacent to the marsh unit. If both salt marsh sparrow habitat and SAV are present, the value is 2; if only one is present, the value is 1; if neither are present, the value is 0. (Source: USGS)
    ValueDefinition
    2Presence of priority SALS habitat within the marsh unit, and SAV adjacent to the marsh unit.
    1Presence of priority SALS habitat within the marsh unit, or SAV adjacent to the marsh unit.
    0Absence of priority SALS habitat within the marsh unit, nor SAV adjacent to the marsh unit.
    Quantl
    The quantile bin that a marsh unit is assigned to based on its area. The marsh units with the smallest areas are in quantile 1, and the largest marsh units are in quantile 5. (Source: USGS)
    Range of values
    Minimum:1
    Maximum:5
    Units:None
    AssetScore
    An estimate of the protection a marsh unit provides to an asset (building). The asset score ranges from 0 (minimal protection provided by marsh unit) to 10 (maximal protection). (Source: USGS)
    Range of values
    Minimum:0
    Maximum:9
    Units:None
    VegMU_MgC
    Total biomass carbon in the vegetated portion of the marsh unit. A value of -9999 indicates no data. (Source: USGS)
    Range of values
    Minimum:0.239
    Maximum:204.280
    Units:megagrams carbon
    Pop
    The total population within 50 miles of the park boundary. This value is the same for all marsh units. (Source: USGS)
    ValueDefinition
    16,360,663Total population within 50 miles of the park boundary.
    Edu_Val
    Educational values of marsh units. Marsh units that are within 200 m of visitor's centers, the Floyd Estate, the Watch Hill Boardwalk, walking trails, and the Sunken Forest have educational value (1), others are classified as having no educational value (0). (Source: USGS)
    ValueDefinition
    1Marsh unit has educational value.
    0Marsh unit is not close enough to visitor's centers, the Floyd Estate, the Watch Hill Boardwalk, walking trails, and the Sunken Forest to have educational value.
    Rec_Val
    Recreational value of marsh units. Marsh units that are within 100 m of walking trails, the Watch Hill boardwalk, roads (4WD and regular), campsites, boat access points, the wilderness area, Sunken Forest and the Floyd Estate have recreational value (1), others are classified as having no recreational value (0). (Source: USGS)
    ValueDefinition
    1Marsh unit has recreational value.
    0Marsh unit does not have recreational value.
    Visit
    The total number of visitors to FIIS in 2023. This value is the same for all marsh units. (Source: USGS)
    ValueDefinition
    298,958Total number of visitors to FIIS in 2023.
    Wild
    Marsh units that are within the Wilderness Area have a value of 1, otherwise they have a value of 0. (Source: USGS)
    ValueDefinition
    1Marsh unit is within the Wilderness Area.
    0Marsh unit is not within the Wilderness Area.
    NHS
    Marsh units that are within 1 km of a National Historic Site (NHS, NRHP) have a value of 1, otherwise they have a value of 0. (Source: USGS)
    ValueDefinition
    1Marsh unit is within 1 km of a National Historic Site.
    0Marsh unit is not within 1 km of a National Historic Site.
    CL
    Marsh units that are within 1 km of a Cultural Landscape have a value of 1, otherwise they have a value of 0. (Source: USGS)
    ValueDefinition
    1Marsh unit is within 1 km of a Cultural Landscape.
    0Marsh unit is not within 1 km of a Cultural Landscape.
    NHS_CL
    Marsh unit that are within 1 km of either an NHS or CL site or both have a value of 1 or 2, respectively, otherwise they have a value of 0. (Source: USGS)
    ValueDefinition
    2Marsh unit is within 1 km of a NHS and a CL site.
    1Marsh unit is within 1 km of a NHS or a CL site.
    0Marsh unit is not within 1 km of a NHS nor a CL site.
    Arch
    Marsh unit that is within 100 m of an area of archeological concern has a value of 1, otherwise it has a value of 0. (Source: USGS)
    ValueDefinition
    1Marsh unit is within 100 m of an area of archeological concern.
    0Marsh unit is not within 100 m of an area of archeological concern.
    FLG
    Marsh unit flag indicating anomalous marsh units based on absence of vegetation, elevation, surface area and tidal range extrapolation. FLG values indicate: (-1) no vegetated area in the marsh unit; (-10) marsh unit elevation higher than the 99.8 percentile; (-100) marsh unit elevation less than the 0.2 percentile; (-200) greater than 25 percent of the marsh unit elevation is hydro-flattened; (-1000) marsh unit surface area less than 900 m2; (-10000) mean tidal range of marsh unit is extrapolated; and (0) no flag. Combination of negative values indicates a combination of flags. For example, -1001 indicates no vegetated area and area less than 900 m2.This attribute was carried over from the original source, mu_lifespan_NY.shp. (Source: USGS)
    Range of values
    Minimum:-1001
    Maximum:0
    Units:None
    InOutPark
    Classification of marsh unit as either inside or outside of the park boundary. (Source: USGS)
    ValueDefinition
    inMarsh unit that is inside the park boundary.
    outMarsh unit that is outside the park boundary.
    Entity_and_Attribute_Overview:
    In this dataset, metrics are calculated for marsh units of Fire Island National Seashore, New York (FIIS) to be used in an SDM framework to prioritize management actions. All attributes, as well as attribute definitions, are included even if they are not present in any of the marsh units in the park. This is to ensure consistency across parks and recognition that the attribute is not present rather than unaccounted for.
    Entity_and_Attribute_Detail_Citation: USGS

Who produced the data set?

  1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)
    • Kate V. Ackerman
    • Brian D. Andrews
    • Neil K. Ganju
    • Zafer Defne
  2. Who also contributed to the data set?
  3. To whom should users address questions about the data?
    U.S. Geological Survey
    Attn: Kate V. Ackerman
    Geologist
    384 Woods Hole Road
    Woods Hole, MA

    508-548-8700 x2331 (voice)
    508-457-2310 (FAX)
    kackerman@usgs.gov

Why was the data set created?

This shapefile provides the geospatial metrics generated for Fire Island National Seashore (FIIS) to be used in the structured decision making (SDM) process.

How was the data set created?

  1. From what previous works were the data drawn?
    mu_lifespan_NY.shp (source 1 of 28)
    Defne, Z., Ganju, N.K., and Ackerman, K.V., 2024, Lifespan of marsh units in New York salt marshes: data release DOI:10.5066/P14MB99B, U.S. Geological Survey, Coastal and Marine Hazards and Resources Program, Woods Hole Coastal and Marine Science Center, Woods Hole, MA.

    Online Links:

    Type_of_Source_Media: online
    Source_Contribution:
    This shapefile is used as a starting point for the SDM metrics shapefile published here (FIIS_SDM_Metrics.shp). The marsh unit unique identification number (FID_CMU), the total area of the marsh unit (ATOT_M2), the area of the vegetated portion of the marsh unit (AVEG_M2), the lifespan under global mean sea-level rise of 0.5m and 1.0m by 2100 (GMSL05, GMSL10), the unvegetated to vegetated marsh ratio (UVVR), and flagged anomalous units (FLG) are all carried from the source shapefile (mu_lifespan_NY.shp) into the FIIS_SDM_Metrics.shp shapefile. Downloaded in April 2024.
    relative_tidal_elevation.tif (source 2 of 28)
    Holmquist, J.R., and Windham-Myers, L., 2021, Relative Tidal Marsh Elevation Maps with Uncertainty for Conterminous USA, 2010: ORNL DAAC, Oak Ridge, TN.

    Online Links:

    Type_of_Source_Media: online
    Source_Contribution:
    Used the relative tidal elevation (elevation normalized to the tidal range), termed Zstar (Z*). Z* = (orthometric elevation (m) - mean sea level (m)) / (mean high water (m) - mean sea level(m)). Downloaded in April 2024.
    marsh_migration.tif (source 3 of 28)
    National Oceanic and Atmospheric Administration (NOAA) Office for Coastal Management (OCM), 2019, NOAA Office for Coastal Management Marsh Migration: NOAA's Ocean Service, Office for Coastal Management (OCM), Charleston, SC.

    Online Links:

    Type_of_Source_Media: online
    Source_Contribution:
    Marsh migration inland boundary under sea-level rise. Downloaded the New York data in January 2024.
    NHDPlus Catchment (source 4 of 28)
    U.S. Geological Survey, 2022, National Hydrography Dataset Plus (NHD Plus): U.S. Geological Survey, Reston, VA.

    Online Links:

    Type_of_Source_Media: online
    Source_Contribution:
    NHD Plus catchment polygons for HUC 0203. Downloaded in January 2025.
    WavePower (source 5 of 28)
    Aretxabaleta, A.L., Defne, Z., Kalra, T.S., Blanton, B.O., and Ganju, N.K., 2022, Climatological wave height, wave period and wave power along coastal areas of the East Coast of the United States and Gulf of Mexico: data release DOI:10.5066/P9HJ0JIQ, U.S. Geological Survey, Coastal and Marine Hazards and Resources Program, Woods Hole Coastal and Marine Science Center, Woods Hole, MA.

    Online Links:

    Type_of_Source_Media: online
    Source_Contribution:
    Wave power, which is extracted from a grid derived from model simulations, is the energy per unit length generated by the movement of ocean waves. The wave power for individual marsh units uses a conservative interpolation that relies on the grid resolution of the model simulation. Downloaded in March 2023.
    Vessel_Location (source 6 of 28)
    Bureau of Ocean Energy Management (BOEM) and the National Oceanic and Atmospheric Administration (NOAA), 2024, Vessel traffic data.

    Online Links:

    Type_of_Source_Media: online
    Source_Contribution:
    Downloaded one year (2023) of point vessel traffic data. Downloaded in November 2024.
    NWI.shp (source 7 of 28)
    U.S. Fish and Wildlife Service, 2024, National Wetlands Inventory: U.S. Fish and Wildlife Service, Washington, D.C..

    Online Links:

    Type_of_Source_Media: online
    Source_Contribution: Downloaded the wetlands data for New York in December 2024.
    NortheastUSDitches_Polyline.shp (source 8 of 28)
    Peck, E.K., Walker, J.E., Woodruff, J.D., and Ganju, N.K., 2024, Linear Ditches of Northeastern U.S. Coastal Marshes from Maine to Virginia Derived from 2023 2D Aerial Imagery Basemap: data release DOI:10.5066/P13WF8ZT, U.S. Geological Survey, Reston, VA.

    Online Links:

    Type_of_Source_Media: online
    Source_Contribution: Ditches shapefile. Downloaded in March 2024.
    SAV.shp (source 9 of 28)
    New York Department of State, Office of Planning and Development, 20210112, 2018 Long Island South Shore Estuary Seagrass Habitat Polygon Data Set: New York Department of State, Albany, NY.

    Online Links:

    Type_of_Source_Media: online
    Source_Contribution:
    Shapefile of the location of SAV beds in 2018. Downloaded in October 2024.
    ACJV_SALS_Priority_Marshes (source 10 of 28)
    Luke, K., 20241006, FWS Saltmarsh Restoration Priorities for the Saltmarsh Sparrow- Atlantic Coast Joint Venture (ACJV): U.S. Fish and Wildlife Service, Panama City, FL.

    Online Links:

    Type_of_Source_Media: online
    Source_Contribution:
    Salt marshes that are characterized as "priority" marshes are used in this analysis. Downloaded in October 2024.
    FIIS_Building_Polygon (source 11 of 28)
    Service, National Park, 2014, Fire Island Sentinel Sites.

    Online Links:

    Type_of_Source_Media: online
    Source_Contribution:
    Shapefile that includes FIIS buildings, here we are only using the NPS buildings. Downloaded October 2024.
    USGS_CCL_MaximumCCL_2022.tif (source 12 of 28)
    Sterne, T.K., Pendleton, E.A., Lentz, E.E., and Henderson, R.E., 2023, Coastal Change Likelihood in the U.S. Northeast Region: Maine to Virginia- Maximum Change Likelihood: data release DOI:10.5066/P96A2Q5X, U.S. Geological Survey, Reston, VA.

    Online Links:

    Type_of_Source_Media: online
    Source_Contribution:
    Dataset that estimates the coastal change likelihood across the Northeast. Downloaded in March 2024.
    CMU_FIIS.shp (source 13 of 28)
    Defne, Z., and Ganju, N.K., 2018, Conceptual marsh units for Fire Island National Seashore and central Great South Bay salt marsh complex, New York: data release DOI:10.5066/P95U2MQ7, U.S. Geological Survey, Coastal and Marine Hazards and Resources Program, Woods Hole Coastal and Marine Science Center, Woods Hole, MA.

    Online Links:

    Type_of_Source_Media: online
    Source_Contribution:
    Conceptual marsh units that have vegetated and unvegetated polygons delineated. Downloaded in April 2024.
    BiomassC_CONUSTidalMarshes_gCm2.tif (source 14 of 28)
    Woltz, V.L., Stagg, C. LaFosse, Byrd, K.B., Windham-Myers, L., Rovai, A.S., and Zhu, Z., 2023, Biomass Carbon Stock and Net Primary Productivity in Tidal Herbaceous Wetlands of the Conterminous United States: U.S. Geological Survey, Reston, VA.

    Online Links:

    Type_of_Source_Media: online
    Source_Contribution:
    Dataset of the biomass carbon stock in coastal herbaceous wetlands. The first link is to the data release and the second link is to the specific dataset used. Downloaded in March 2024.
    Census_Blocks.shp (source 15 of 28)
    U.S. Department of Commerce, U.S. Census Bureau, Geography Division, Geospatial Products Branch, 2023, TIGER/Line Shapefile, 2020 Census Block: U.S. Census Bureau, Washington, D.C..

    Online Links:

    Type_of_Source_Media: online
    Source_Contribution: Census blocks. Downloaded in March 2024.
    Locations_Interest.shp (source 16 of 28)
    U.S. Geological Survey/National Park Service, 2024, FIIS Points of Interest.

    Type_of_Source_Media: digital
    Source_Contribution:
    Digitized locations of Visitors Centers, Floyd Estate, Watch Hill boardwalk, walking trails, Sunken Forest using https://www.nps.gov/fiis/planyourvisit/maps.htm and https://www.nps.gov/fiis/learn/upload/02_Burma-Trail-Map-508-Compliant.pdf and aerial imagery (Esri World Imagery) for reference. At the time of publication, these data were not digitally available from the National Park Service.
    Campsites.shp (source 17 of 28)
    Fire Island National Seashore, 2024, FIIS Campsites.

    Online Links:

    Type_of_Source_Media: online
    Source_Contribution: Location of campsites. Accessed data August 2024.
    Roads.shp (source 18 of 28)
    U.S. Geological Survey, National Geospatial Technical Operations Center, 2020, USGS National Structures Dataset (NSD) New York.

    Online Links:

    Type_of_Source_Media: online
    Source_Contribution: Location of roads. Accessed data August 2024.
    Ferry_Terminals.shp (source 19 of 28)
    Fire Island National Seashore, 2024, FIIS Ferry Terminals.

    Online Links:

    Type_of_Source_Media: online
    Source_Contribution: Digitized locations of ferry terminals, August 2024.
    Wilderness.shp (source 20 of 28)
    Fire Island National Seashore, 2007, OG Pike Fire Island High Dune Wilderness Area.

    Online Links:

    Type_of_Source_Media: online
    Source_Contribution:
    Location of the wilderness area. Downloaded data in August 2024.
    Annual_Visitation (source 21 of 28)
    Service, National Park, 2024, Annual Park Recreation Visits (1967-Last Calendar Year): National Park Service, Washington, D.C..

    Online Links:

    Type_of_Source_Media: online
    Source_Contribution: Number of visitors to FIIS in 2023. Downloaded in August 2024.
    Cultural_1.shp (source 22 of 28)
    National Park Service, Cultural Resource GIS Facility, 20220125, Cultural Resource District Polygon: National Park Service, Washington, DC.

    Type_of_Source_Media: online
    Source_Contribution:
    This dataset was accessed and used by Dennis Skidds (NPS) to identify marsh units that are within 1 kilometer (km) of National Historic Sites and Cultural Landscapes.
    Cultural_2.shp (source 23 of 28)
    National Park Service, Cultural Resource GIS Facility, 20220125, Cultural Resource Object Polygon: National Park Service, Washington, DC.

    Type_of_Source_Media: online
    Source_Contribution:
    This dataset was accessed and used by Dennis Skidds (NPS) to identify marsh units that are within 1 km of National Historic Sites and Cultural Landscapes.
    Cultural_3.shp (source 24 of 28)
    National Park Service, Cultural Resource GIS Facility, 20220125, Cultural Resource Site Polygon: National Park Service, Washington, DC.

    Type_of_Source_Media: online
    Source_Contribution:
    This dataset was accessed and used by Dennis Skidds (NPS) to identify marsh units that are within 1 km of National Historic Sites and Cultural Landscapes.
    Cultural_4.shp (source 25 of 28)
    National Park Service, Cultural Resource GIS Facility, 20220125, Cultural Resource Site Point: National Park Service, Washington, DC.

    Type_of_Source_Media: online
    Source_Contribution:
    This dataset was accessed and used by Dennis Skidds (NPS) to identify marsh units that are within 1 km of National Historic Sites and Cultural Landscapes.
    Cultural_5.shp (source 26 of 28)
    National Park Service, Cultural Resource GIS Facility, 20220125, Cultural Resource Site Line: National Park Service, Washington, DC.

    Type_of_Source_Media: online
    Source_Contribution:
    This dataset was accessed and used by Dennis Skidds (NPS) to identify marsh units that are within 1 km of National Historic Sites and Cultural Landscapes.
    FIIS_Arch_Concern.shp (source 27 of 28)
    Fire Island National Seashore, 2024, Area of archeological concern.

    Type_of_Source_Media: digital
    Source_Contribution:
    At the time of publication, areas of archeological concern were not publicly available from National Park Service (NPS). Received the data from FIIS, December 2024.
    NPS_boundary.shp (source 28 of 28)
    Service, National Park, 2022, NPS Unit Boundary-derived Areas of Analysis, Fall 2021: NPS Natural Resources Inventory and Monitoring Division, Washington, DC.

    Online Links:

    Type_of_Source_Media: online
    Source_Contribution:
    Used for delineation of park boundaries. Downloaded data in July 2022.
  2. How were the data generated, processed, and modified?
    Date: 2024 (process 1 of 20)
    All process steps were performed by either Kate Ackerman or Brian Andrews (contact information in this process step and the next), using ArcGIS Pro (ver.3.2.1). For simple operations the name of the geoprocessing tool used is given in capital letters; for complex operations, the name of the geoprocessing tool used is given in capital letters and any critical parameters used are given in parentheses, separated by a semicolon, immediately after the tool name. The input and output file names are provided in [square brackets] when necessary. Units for length and area calculations are meters (m) and square meters (m2) unless otherwise stated. Person who carried out this activity:
    Kate Ackerman
    U.S. Geological Survey
    Geologist
    384 Woods Hole Road
    Woods Hole, MA
    US

    508-548-8700 x2331 (voice)
    508-457-2310 (FAX)
    kackerman@usgs.gov
    Date: 2024 (process 2 of 20)
    Export [mu_lifespan_NY.shp] to create a new shapefile [FIIS_SDM_Metrics.shp], keeping only the marsh units that are in the FIIS park boundary, and the fields that are needed for the SDM performance metrics: the marsh unit unique identification number (FID_CMU), the total area of the marsh unit (ATOT_M2), the area of the vegetated portion of the marsh unit (AVEG_M2), the lifespan under global mean sea-level rise of 0.5m and 1.0m by 2100 (GMSL05, GMSL10), the unvegetated to vegetated marsh ratio (UVVR), and the flag denoting anomalous marsh units (FLG). Project the shapefile from WGS 1984 Web Mercator Auxiliary Sphere to NAD 1983 (2011) UTM 18N. Person who carried out this activity:
    Brian Andrews
    U.S. Geological Survey
    Geographer
    384 Woods Hole Road
    Woods Hole, MA
    US

    508-548-8700 x2348 (voice)
    508-457-2310 (FAX)
    bandrews@usgs.gov
    Data sources used in this process:
    • mu_lifespan_NY.shp
    Data sources produced in this process:
    • FIIS_SDM_Metrics.shp
    Date: 2024 (process 3 of 20)
    Create attribute "Zstar" to calculate elevation relative to tidal range. Calculate the mean relative wetland elevation value relative to tidal range (Zstar (Z*)) within each marsh unit (FID_CMU). Zstar, the relative tidal elevation value, is a metric that normalizes elevation to the tidal amplitude at mean high water. Z* = (orthometric elevation - mean sea level) / (mean high water - mean sea level).
    Run ZONAL STATISTICS AS TABLE (feature zone data: [FIIS_SDM_Metrics.shp], zone field: FID_CMU, value raster: [relative_tidal_elevation.tif], statistics type= Mean) to calculate the average Z* value for each marsh unit. In [FIIS_SDM_Metrics.shp], add new attribute "Zstar" (Double) to attribute table and populate with results of zonal statistics (MEAN) by joining via the "FID_CMU" field. Assign a value of -9999 for marsh units that do not have Zstar data. Data sources used in this process:
    • FIIS_SDM_Metrics.shp
    • relative_tidal_elevation.tif
    Data sources produced in this process:
    • FIIS_SDM_Metrics.shp
    Date: 2024 (process 4 of 20)
    Create attribute “AMIG_M2” to assess the marsh migration potential of each marsh unit, calculated in terms of available migration area, under 2 feet of local sea-level rise, for each marsh unit.
    This process step followed the methodology detailed in "Chesapeake Bay marsh migration potential under sea-level rise" (Defne and others, 2025), and used these input datasets for FIIS: (1) Marsh migration datasets for New York [marsh_migration.tif] (2) NHD datasets for HUC 0203 [NHDPlus Catchment].
    The migration space is based on the NOAA marsh migration predictions under 2 feet of local sea-level rise and divided into smaller parcels by using the National Hydrography Dataset Plus (NHD Plus) catchments. The marsh migration space is then distributed to the marsh units. Data sources used in this process:
    • FIIS_SDM_Metrics.shp
    • marsh_migration.tif
    • NHDPlus Catchment
    Data sources produced in this process:
    • FIIS_SDM_Metrics.shp
    Date: 2024 (process 5 of 20)
    Create attribute "WavePwr" to assign a wave power value to each marsh unit. Create "Wake_Norm" to assess the wake exposure of each marsh unit.
    Wave power: 1. Create a raster surface dataset from the feature points, using inverse distance weighting (IDW). The parameters used in the IDW tool are conservative so that additional variability is not added to the wave power input dataset. a) Remove data points in the ocean as well as points with a value of zero on the beach. b) IDW (Input point features: [WavePower.shp]; Output Cell Size=0.0001 degree; Power=2; Search Radius=Variable; Number of Points=1) to obtain [WavePower_IDW.tif].
    2. Clip the raster to marsh boundaries. A buffer zone is created around the marsh boundaries to facilitate alternative interpolation and clipping options in future studies. a) Create 300 m buffer around the marsh units polygons to create a clipping mask [mu_buff300m.shp]. BUFFER (Side type= Full; Method= Geodesic; Dissolve type= All). b) CLIP the raster [WavePower_IDW.tif] with the clipping mask [mu_buff300m.shp] to obtain [WavePower_IDW_clip.tif]. c) EXTRACT BY MASK (Input raster= [WavePower_IDW_clip.tif]; Mask=[FIIS_SDM_Metrics.shp]) to obtain [WavePower_IDW_MU.tif].
    3. Calculate mean wave power value for each marsh unit. a) PROJECT (Output coordinate system=GCS WGS 1984) [FIIS_SDM_Metrics.shp] to [mu_diss_WGS84]. b) ZONAL STATISTICS AS TABLE (Feature Zone Data=[mu_diss_WGS84.shp]; zone field=FID_CMU; Value Raster=[WavePower_IDW_MU.tif]; Output Table=[wp]; Statistics type=MEAN). c) JOIN FIELD (Input table=[FIIS_SDM_Metrics.shp]; Input join field=FID_CMU; Join Table=[wp]; Output join field=FID_CMU; Join Field= MEAN). Change “MEAN” to “WavePwr.”
    Wake Exposure: 1. Determine the number of boats that are within 500 m of each marsh unit. SUMMARIZE NEARBY (Input=[FIIS_SDM_Metrics.shp], Input summary features= [Vessel_Location], Output= [MU_Vessel_summary], distance measurement: straight line; distance: 500 meters; keep polygons with no points).
    2. Calculate "Wake_Norm" to normalize the point counts to a value between 0 and 1. Wake_Norm= (Point_count - minimum value)/ (Maximum value - minimum value). Join "Wake_Norm" to [FIIS_SDM_Metrics.shp]. Data sources used in this process:
    • FIIS_SDM_Metrics.shp
    • WavePower
    • Vessel_Location
    Data sources produced in this process:
    • FIIS_SDM_Metrics.shp
    Date: 2024 (process 6 of 20)
    Create attribute “NWIclass” to calculate the number of different NWI marsh subclass types found within a marsh unit.
    (1) Create a shapefile of the NWI classes that are used for the marsh unit analysis. From [NWI.shp] SELECT (ATTRIBUTE LIKE 'E2%EM%' OR ATTRIBUTE LIKE 'E2AB3%' OR ATTRIBUTE LIKE 'E2EM%' OR ATTRIBUTE LIKE 'E2SS%' OR ATTRIBUTE LIKE 'E2US4%'), EXPORT features to create [NWI_exclusive_select.shp]. Add an additional field that captures the first 5 digits of the NWI attribute field (no modifiers are retained).
    (2) PAIRWISE INTERSECT the NWI [NWI_exclusive_select.shp] and the marsh units [FIIS_SDM_Metrics.shp] to assign NWI classes to each marsh unit. DISSOLVE the resulting shapefile (Dissolve field: FID_CMU, Concatenate) to obtain a list of all NWI classes found in each marsh unit. Calculate the number of different NWI subclasses found in each marsh unit. Data sources used in this process:
    • FIIS_SDM_Metrics.shp
    • NWI.shp
    Data sources produced in this process:
    • FIIS_SDM_Metrics.shp
    Date: 2024 (process 7 of 20)
    Create attribute "Ditchkmkm2" to calculate the density of ditches for each marsh unit. It is calculated by summing the linear length of ditches (km) divided by the area of each marsh unit (square kilometers). The final value for each marsh unit is ditching intensity (linear kilometers of ditch per square kilometer of marsh unit area).
    PAIRWISE INTERSECT the ditches [NortheastUSDitches_Polyline.shp] and marsh units [FIIS_SDM_Metrics.shp] then SUMMARIZE ATTRIBUTES by FID_CMU to get total length of ditches in each marsh unit. Calculate the ditch density (km/km2): total length of ditches (km) in a marsh, divided by the total marsh unit area (km2). Data sources used in this process:
    • FIIS_SDM_Metrics.shp
    • NortheastUSDitches_Polyline.shp
    Data sources produced in this process:
    • FIIS_SDM_Metrics.shp
    Date: 2024 (process 8 of 20)
    Create attribute "BioDiv" that provides information on the biodiversity of the marsh unit, which is the summation of the "SALS_P" (whether the marsh unit intersects a “priority marsh” for Saltmarsh Sparrow) and the "SAV" (whether the marsh unit is within 100m of seagrass beds) attributes.
    SALS_P: SELECT BY LOCATION (intersect) [ACJV_SALS_Priority_Marshes] and [FIIS_SDM_Metrics.shp] to identify marsh units that intersect priority habitat for Saltmarsh Sparrow. If they intersect, the marsh unit is assigned a value of 1 for the “SALS_P” attribute.
    SAV: SELECT BY LOCATION (intersect, 100 m) [SAV.shp] and [FIIS_SDM_Metrics.shp] to identify marsh units that have seagrass within 100 m of the marsh unit. If seagrass beds are within 100 m of the marsh unit, the marsh unit is assigned a value of 1 for the “SAV” attribute.
    BioDiv: The “BioDiv” attribute is the sum of the “SALS_P” and “SAV” attributes. Data sources used in this process:
    • FIIS_SDM_Metrics.shp
    • ACJV_SALS_Priority_Marshes
    • SAV.shp
    Data sources produced in this process:
    • FIIS_SDM_Metrics.shp
    Date: 2024 (process 9 of 20)
    Create attribute “Quantl” to compare the size of marsh units across the Park. Based on the total marsh unit area, the marsh units are binned into 5 equal area bins. Each marsh unit is placed into a bin based on its size (bin 1 contains the smallest marsh units; bin 5 contains the largest marsh units).
    Calculate the total area of all marsh units, sort marsh units by size, divide the dataset into five approximately equal parts based on area. The smallest marsh units will have a Quantl value of 1, the largest marsh units will have a Quantl value of 5. Data sources used in this process:
    • FIIS_SDM_Metrics.shp
    Data sources produced in this process:
    • FIIS_SDM_Metrics.shp
    Date: 2024 (process 10 of 20)
    Create attribute "AssetScore" to estimate the protection a marsh unit provides to an asset (building). The Asset Score is calculated by dividing the maximum Coastal Change Likelihood (USGS_CCL_MaximumCCL_2022.tif) score within 100 m of an asset by the distance in meters (binned) from the asset to the marsh unit. The Asset Score ranges from 0 (minimal protection provided by marsh unit) to 10 (maximal protection).
    1)PROJECT source shapefiles from WGS 1984 Web Mercator coordinate system to NAD 83 (2011) UTM 18N and output as feature classes within a geodatabase to ensure distance calculations are accurate. Source files: marsh units: [FIIS_SDM_Metrics.shp]; buildings (use only NPS buildings): [FIIS_Building_Polygon]; output: [FIIS_BuildingFeatures_UTM18].
    2)Calculate the maximum CCL value within 100 m of each of the assets (buildings) within FIIS boundary. BUFFER [FIIS_BuildingFeatures_UTM18] by 100 m, output= [FIIS_BID100mBuff]. ZONAL STATISTICS AS TABLE (Input: [FIIS_BID100mBuff]; zone field=BID; Input Value Raster: [USGS_CCL_2022.tif]; Output table: [FIIS_BuildingMaxCCL_100m]; Statistics Type=Maximum).
    3)Calculate the distance in meters from the buildings [FIIS_BuildingFeatures_UTM18] to the closest point along the boundary of all marsh units [FIIS_SDM_Metrics.shp] that are within 1 km of each feature in [FIIS_BuildingFeatures_UTM18]. GENERATE NEAR TABLE (Output table: [FIIS_BuildingsNearMU_1km]). Only need to retain the fields "IN_FID", "NEAR_FID", and "NEAR_DIST" from the output table.
    4)Join (JOIN FIELD) the MAX CCL value from table [FIIS_BuildingMaxCCL_100m] (join field=BID) to the output table [FIIS_BuildingsNearMU_1km] (join field=IN_FID; Transfer Fields=MAX).
    5)ADD FIELDS (multiple) (Input Table: [FIIS_SDM_Metrics.shp]; Field Names: "Dist" (Short) and "AssetScore" (Double)).
    6)ADD JOIN (Join one to many) (Input Table: [FIIS_SDM_Metrics.shp]; input field=OBJECTID; Join Table: [FIIS_BuildingsNearMU_1km]; Join Field: NEAR_FID; transfer all fields). EXPORT joined feature class to [FIIS_SDM_Metrics_AS].
    7) Calculate the "AssetScore" field in 2 steps. In [FIIS_SDM_Metrics_AS], first CALCULATE FIELD "Dist" by rounding up the "NEAR_DIST" value (Data type=double from step 3 and 6) in meters to the nearest 100, then dividing the rounded number by 100. For example, a "NEAR_DIST" value of 23.55 m rounds to 100, then divided by 100 gives a “Dist” value of 1; a "NEAR_DIST" of 176.16 m gives "Dist" value of 2. Second, CALCULATE FIELD "AssetScore" by dividing "MAX" (max CCL) by "DIST."
    8)Run PAIRWISE DISSOLVE (input file: [FIIS_SDM_Metrics_AS]; Dissolve field: FID_CMU; Statistics field: AssetScore; Statistics Type: Maximum; Output: [FIIS_SDM_Metrics_AS_Dissolve]) to dissolve duplicate "FID CMU" records from the one-to-many join in step 6. This final step retains the maximum "AssetScore" for any one-to-many relationships between each marsh unit and building pair(s). The output dissolved feature class does not retain all the fields from the source [FIIS_SDM_Metrics_AS] and only retains "FID_CMU" and "MAX_AssetScore."
    9)JOIN FIELD "MAX_AssetScore" from [FIIS_SDM_Metrics_AS] back into original source [FIIS_SDM_Metrics.shp] using the "FID_CMU" field. Data sources used in this process:
    • FIIS_SDM_Metrics.shp
    • FIIS_Building_Polygon
    • USGS_CCL_MaximumCCL_2022.tif
    Data sources produced in this process:
    • FIIS_SDM_Metrics.shp
    Date: 2024 (process 11 of 20)
    Create attribute “VegMU_MgC” to summarize the amount of biomass carbon in the vegetated part of the marsh unit.
    Extract the vegetated portion of the marsh unit polygons. SELECT BY ATTRIBUTES from [CMU_FIIS.shp] within and adjacent to the park boundary [NPS_boundary.shp] where "TYP"= 'vegetated'; output: [CMU_FIIS_VEG.shp]. PROJECT [CMU_FIIS_VEG.shp] to Albers_Conical_Equal_Area to match the projection of the biomass carbon file.
    Run ZONAL STATISTICS AS TABLE (feature zone data: [CMU_FIIS_VEG.shp], zone field: FID_CMU, value raster: [BiomassC_CONUSTidalMarshes_gCm2.tif], Statistics type=Mean) to get the average biomass carbon for the vegetated portion of the marsh unit. JOIN the MEAN value to [CMU_FIIS_VEG.shp]. Multiply MEAN by the vegetated area of the marsh unit to get total grams of carbon in the vegetated portion of the marsh unit. Report the value in megagrams of carbon (MgC). Assign a value of -9999 for marsh units that do not have carbon data. Data sources used in this process:
    • FIIS_SDM_Metrics.shp
    • CMU_FIIS.shp
    • BiomassC_CONUSTidalMarshes_gCm2.tif
    Data sources produced in this process:
    • FIIS_SDM_Metrics.shp
    Date: 2024 (process 12 of 20)
    Create new attribute “Pop” to calculate the total population within 50 miles of the marsh units. The population value is the same for all marsh units.
    SELECT BY LOCATION (intersect, 50 miles) [Census_Blocks.shp] and [FIIS_SDM_Metrics.shp]. Calculate total population in the selected census blocks. Data sources used in this process:
    • FIIS_SDM_Metrics.shp
    • Census_Blocks.shp
    Data sources produced in this process:
    • FIIS_SDM_Metrics.shp
    Date: 2024 (process 13 of 20)
    Create attribute “Edu_Val” that identifies marsh units that are of natural and cultural history educational value to the park. For FIIS, marsh units within 200 m of visitor's centers, the Floyd Estate, the Watch Hill Boardwalk, walking trails, and the Sunken Forest are identified.
    SELECT BY LOCATION (intersect, 200m) [Locations_Interest.shp] and [FIIS_SDM_Metrics.shp] to identify marsh units that are within 200 m of the features of interest. If the features are within 200 m of the marsh unit, the marsh unit is assigned a value of 1. Data sources used in this process:
    • FIIS_SDM_Metrics.shp
    • Locations_Interest.shp
    Data sources produced in this process:
    • FIIS_SDM_Metrics.shp
    Date: 2024 (process 14 of 20)
    Create attribute “Rec_Val” that identifies marsh units that are of recreational value to the park. For FIIS, marsh units within 100 m of walking trails, the Watch Hill boardwalk, roads (4WD and regular), campsites, boat access points, the wilderness area, Sunken Forest and the Floyd Estate are identified.
    SELECT BY LOCATION (intersect, 100m) [Locations_Interest.shp], [Campsites.shp], [Roads.shp], [Ferry_Terminals.shp], [Wilderness.shp] and [FIIS_SDM_Metrics.shp] to identify marsh units that are within 100 m of these features. If the features are within 100 m of the marsh unit, the marsh unit is assigned a value of 1. Data sources used in this process:
    • FIIS_SDM_Metrics.shp
    • Locations_Interest.shp
    • Campsites.shp
    • Roads.shp
    • Ferry_Terminals.shp
    • Wilderness.shp
    Data sources produced in this process:
    • FIIS_SDM_Metrics.shp
    Date: 2024 (process 15 of 20)
    Create new attribute “Visit” that is the total number of visitors to the park in 2023. This value is the same for all marsh units.
    The number of visitors to FIIS in 2023 was obtained from [Annual_Visitation]. Data sources used in this process:
    • FIIS_SDM_Metrics.shp
    • Annual_Visitation
    Data sources produced in this process:
    • FIIS_SDM_Metrics.shp
    Date: 2024 (process 16 of 20)
    Create attribute "Wild" that identifies marsh units that are within the Wilderness Area.
    SELECT BY LOCATION (intersect) [Wilderness.shp] and [FIIS_SDM_Metrics.shp] to identify marsh units that intersect the Wilderness area of FIIS. If they intersect, the marsh unit is assigned a value of 1. Data sources used in this process:
    • FIIS_SDM_Metrics.shp
    • Wilderness.shp
    Data sources produced in this process:
    • FIIS_SDM_Metrics.shp
    Date: 2024 (process 17 of 20)
    Create 3 attributes “NHS,” “CL,” and “NHS_CL” to identify marshes that are close to cultural and historical resources. "NHS" identifies marsh units that are within 1 km of a historic site (National Historic Site (NHS), National Register of Historic Places (NRHP)), "CL" identifies marsh units that are within 1 km of a Cultural Landscape (CL). The attribute "NHS_CL" indicates marsh unit that are within 1 km of either an NHS or CL site or both (value of 1 or 2, respectively).
    Dennis Skidds (NPS) aggregated the park-restricted data to determine whether a marsh unit is within 1 km of the cultural and historical resources. Person who carried out this activity:
    Dennis Skidds
    National Park Service
    Regional GIS Program Manager
    1 Greenhouse Rd
    Kingston, RI
    US

    401-374-4994 (voice)
    dennis_skidds@nps.gov
    Data sources used in this process:
    • FIIS_SDM_Metrics.shp
    • Cultural_1.shp
    • Cultural_2.shp
    • Cultural_3.shp
    • Cultural_4.shp
    • Cultural_5.shp
    Data sources produced in this process:
    • FIIS_SDM_Metrics.shp
    Date: 2024 (process 18 of 20)
    Create an attribute "Arch" to denote whether a marsh unit is within 100 m of an area of archeological concern.
    SELECT BY LOCATION (intersect) [FIIS_Arch_Concern.shp] and [FIIS_SDM_Metrics.shp] to identify marsh units that are within 100 m of an area of archeological concern. If the features are within 100 m of the marsh unit, the marsh unit is assigned a value of 1. Data sources used in this process:
    • FIIS_SDM_Metrics.shp
    • FIIS_Arch_Concern.shp
    Data sources produced in this process:
    • FIIS_SDM_Metrics.shp
    Date: 2024 (process 19 of 20)
    Create an attribute "InOutPark" to denote whether a marsh unit is inside or outside of the park boundary. SELECT BY LOCATION (intersect) [NPS_boundary.shp] and [FIIS_SDM_Metrics.shp] to identify whether the marsh unit is inside or outside of the park boundary. Data sources used in this process:
    • FIIS_SDM_Metrics.shp
    • NPS_boundary.shp
    Data sources produced in this process:
    • FIIS_SDM_Metrics.shp
    Date: 2024 (process 20 of 20)
    PROJECT (Output coordinate system=WGS 1984 Web Mercator Auxiliary Sphere) [FIIS_SDM_Metrics.shp] to Web Mercator. Data sources used in this process:
    • FIIS_SDM_Metrics.shp
    Data sources produced in this process:
    • FIIS_SDM_Metrics.shp
  3. What similar or related data should the user be aware of?
    Defne, Z., Ackerman, K.V., Andrews, B.D., and Ganju, N.K., 2025, Chesapeake Bay marsh migration potential under sea-level rise: data release DOI:10.5066/P18BWN2U, U.S. Geological Survey, Coastal and Marine Hazards and Resources Program, Woods Hole Coastal and Marine Science Center, Woods Hole, MA.

    Online Links:

How reliable are the data; what problems remain in the data set?

  1. How well have the observations been checked?
    Marsh units, and water and land boundaries, inherit their accuracy from the vertical and horizontal accuracy of the elevation data (source of elevation data is found in Defne and others, 2024), as well as the accuracy of the wetland demarcation provided by the U.S. Fish and Wildlife Service National Wetland Inventory (USFWS NWI).
  2. How accurate are the geographic locations?
    Horizontal accuracy is inherited from the source dataset (Defne and others, 2024) that delineates the marsh units and is considered to be +/- 6 meters (m).
  3. How accurate are the heights or depths?
    Because the elevation values are averaged over delineated polygons, vertical accuracy of marsh unit elevation depends on both the horizontal accuracy of NWI dataset and the vertical accuracy of source elevation data (CoNED). CoNED vertical elevation accuracy was 0.2 m.
  4. Where are the gaps in the data? What is missing?
    The results are specific to the marsh polygons defined within the boundaries of the Fire Island National Seashore (FIIS) salt marsh complex. A detailed on-the-ground analysis of a single site may result in a different interpretation of the wetland and marsh unit boundaries.
  5. How consistent are the relationships among the observations, including topology?
    Marsh units were evaluated for geoprocessing topology errors and, if found, errors were fixed and validated. The polygons were checked for correct geometry and do not overlap. A visual comparison between NAIP imagery was performed at randomly selected sites to verify the land and water boundaries. For UVVR, marsh polygons without any vegetation were assigned a value of -1. For lifespan, negative values indicate the estimated lifespan is depleted and loss is imminent and some flagged units (see description for the FLG variable) are assigned a lifespan estimate of -9999.

How can someone get a copy of the data set?

Are there legal restrictions on access or use of the data?
Access_Constraints No access constraints. Please see 'Distribution Information' for details.
Use_Constraints Each marsh unit is defined for scientific research purposes and should not be used as a sole source of reference for any regulations and policy making. These data are marked with a Creative Commons CC0 1.0 Universal License. These data are in the public domain and do not have any use constraints. Users are advised to read the dataset's metadata thoroughly to understand appropriate use and data limitations.
  1. Who distributes the data set? (Distributor 1 of 1)
    U.S. Geological Survey - ScienceBase
    Denver Federal Center, Building 810, Mail Stop 302
    Denver, CO

    1-888-275-8747 (voice)
    sciencebase@usgs.gov
  2. What's the catalog number I need to order this data set? FIIS_SDM_Metrics.zip (ZIP file contains the shapefile FIIS_SDM_Metrics.shp and the additional shapefile components and FGDC CSDGM metadata in xml format), and a browse graphic (FIIS_SaltMarsh_Browse.png).
  3. What legal disclaimers am I supposed to read?
    Unless otherwise stated, all data, metadata and related materials are considered to satisfy the quality standards relative to the purpose for which the data were collected. Although these data and associated metadata have been reviewed for accuracy and completeness and approved for release by the U.S. Geological Survey (USGS), no warranty expressed or implied is made regarding the display or utility of the data for other purposes, nor on all computer systems, nor shall the act of distribution constitute any such warranty. The USGS or the U.S. Government shall not be held liable for improper or incorrect use of the data described and/or contained herein.
  4. How can I download or order the data?

Who wrote the metadata?

Dates:
Last modified: 11-Dec-2025
Metadata author:
U.S. Geological Survey
Attn: Kate Ackerman
Geologist
384 Woods Hole Road
Woods Hole, MA

508-548-8700 x2331 (voice)
508-457-2310 (FAX)
whsc_data_contact@usgs.gov
Contact_Instructions:
The metadata contact email address is a generic address in the event the person is no longer with USGS.
Metadata standard:
FGDC Content Standard for Digital Geospatial Metadata (FGDC-STD-001-1998)
This page is <https://cmgds.marine.usgs.gov/catalog/whcmsc/SB_data_release/DR_P13E2NM2/FIIS_SDM_Metrics.faq.html>
Generated by mp version 2.9.51 on Mon Dec 15 11:24:11 2025