Robert Welk Kate V. Ackerman Zafer Defne Neil K. Ganju 20200331 2.0 Vector Digital dataset (Polygon) data release 10.5066/P91H426U Woods Hole Coastal and Marine Science Center, Woods Hole, MA U.S. Geological Survey, Coastal and Marine Geology Program https://doi.org/10.5066/P91H426U https://www.sciencebase.gov/catalog/item/5ddd8803e4b04a30051ac1d6 Robert Welk Kate V. Ackerman Zafer Defne Neil Ganju 2020 2.0 data release 10.5066/P91H426U Reston, VA U.S. Geological Survey Suggested citation: Welk, R., Ackerman, K.V., Defne, Z., and Ganju, N.K., 2020, Coastal wetlands of eastern Long Island, New York (ver. 2.0, March 2024): U.S. Geological Survey data release,https://doi.org/10.5066/P91H426U. https://doi.org/10.5066/P91H426U https://www.sciencebase.gov/catalog/item/5dd56511e4b0695797628ca6 This data release contains coastal wetland synthesis products for the geographic region of eastern Long Island, New York, including the north and south forks, Gardiners Island, and Fishers Island. Metrics for resiliency, including unvegetated to vegetated ratio (UVVR), marsh elevation, and mean tidal range, are calculated for smaller units delineated from a Digital Elevation Model, providing the spatial variability of physical factors that influence wetland health. Through scientific efforts initiated with the Hurricane Sandy Science Plan, the U.S. Geological Survey has been expanding national assessment of coastal change hazards and forecast products to coastal wetlands with the intent of providing Federal, State, and local managers with tools to estimate the vulnerability and ecosystem service potential of these wetlands. For this purpose, the response and resilience of coastal wetlands to physical factors need to be assessed in terms of the ensuing change to their vulnerability and ecosystem services. The purpose of this shapefile is to calculate mean tidal range in each marsh unit. Analysis of mean tidal range is part of a comprehensive assessment to identify the factors and their weights in determining the vulnerability and resiliency of salt marshes. Biomass production is positively correlated with mean tidal range in salt marshes along the Atlantic coast of the United States. Recent studies support the idea that enhanced stability of the marshes can be attributed to increased vegetative growth due to increased tidal range. This dataset displays the spatial variation of mean tidal range (i.e. Mean Range of Tides, MN) in the eastern Long Island salt marsh complex. MN was based on the calculated difference in height between mean high water (MHW) and mean low water (MLW) using the VDatum (v3.5) database ( http://vdatum.noaa.gov/ ). 2020 Publication date of original release. Complete None -72.748198 71.885316 41.291362 40.766433 USGS Metadata Identifier USGS:5ddd8803e4b04a30051ac1d6 USGS Thesaurus geospatial datasets wetland ecosystems wetland functions coastal ecosystems coastal processes tides (oceanic) None salt marsh vegetation marsh health estuary Long-Term Ecological Research LTER tidal range ISO 19115 Topic Category oceans inlandWaters environment None Atlantic Ocean United States New York Suffolk County Peconic Bay Moriches Bay Shinnecock Bay Long Island Sound None The mean tidal range for 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. Public domain data from the U.S. Government are freely redistributable with proper metadata and source attribution. Please recognize the U.S. Geological Survey as the source of this information. U.S. Geological Survey Robert J Welk Hydrologic Technician mailing address

2045 Route 112

Coram NY 11727 US 631-736-0783 x141 rwelk@usgs.gov https://www.sciencebase.gov/catalog/file/get/5ddd8803e4b04a30051ac1d6?name=MN_ELI_browse.png&allowOpen=true Graphic that shows mean tidal range overlaying ESRI basemap. PNG Environment as of Metadata Creation: Microsoft 10 Version 6.2 (Build 9200); Esri ArcGIS 10.7.1 (Build 11595) Service Pack N/A (Build N/A); and ArcGIS Pro 2.8.8. NOAA 2016 version 3.5 Silver Spring, MD NOAA http://vdatum.noaa.gov Marsh units and water and land boundaries inherit their accuracy from the source data, eastern Long Island marsh units. Mean range of tides is calculated from the VDatum database, then interpolated on a raster surface and averaged at each marsh unit. If a marsh unit does not overlap with any raster cell center, it is assigned the value of the raster cell with the largest overlap. Polygons do not overlap and mean tidal range is positive. During processing of conceptual marsh units, small polygons (less than 9 square meters) were assumed to be marginal and were assigned the classification from the surrounding majority value. This resulted in polygons that were removed from the dataset and FID CMU values that are not sequential. The results are specific to the marsh polygons as defined within the boundaries of the eastern Long Island 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. Horizontal accuracy for the polygon boundaries is inherited from the source layer, the conceptual marsh units, and is considered to be +/- 6 meters. The point cloud used for calculating tidal range with VDatum had a 0.0005 arc degree (~50-meter) resolution that was interpolated over a 0.0001 arc degree raster prior to clipping and calculating the mean value for each marsh unit. The maximum cumulative uncertainty for the eastern Long Island, NY operational VDatum region is given as 0.12 meters. See Estimation of Vertical Uncertainties in VDatum for more information (https://vdatum.noaa.gov/docs/est_uncertainties.html). This process step and all subsequent process steps were performed in ArcMap (ver. 10.7.1) using tools from ArcToolbox, unless otherwise stated. For complex operations, names of specific tools used are given in CAPITAL letters (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. Calculate values for each marsh unit. DISSOLVE(Input features=[CMU_ELI]; Dissolve field=FID_CMU; Statistics field=ATOT_M2 and FLG with Statistics type= First) to dissolve the vegetated and unvegetated classes in each marsh unit. FLG flags anomalous marsh units based on the absence of vegetation, the elevation, and the surface area, and is set to (-1) no vegetated area; (-10) marsh unit elevation higher than the 99.8 percentile; (-100) marsh unit elevation less than 0.2 percentile; (-1000) marsh unit surface area less than 900 m2; 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. PROJECT(Input coordinate system=WGS 1984 Web Mercator Auxiliary Sphere; Output coordinate system=NAD 1983 UTM Zone 18N; Geographic transformation=WGS 1984 (ITRF00) to NAD 1983) the feature dataset to obtain CMU_ELI 2019 Calculate Mean Range of Tides using the VDatum (v3.5) database covering this region (http://vdatum.noaa.gov/download.php ). Create a 0.0005 arc degrees (~50 meters) spaced point dataset in Matlab (ver. 2012b) for the eastern Long Island domain. Calculate the mean range of tides (MN) as MN=MHW-MLW, where MHW is the mean high water level and MLW is the mean low water level in the VDatum database, and interpolate to the point dataset. The resulting comma-separated file includes columns for latitude, longitude and MN. 2019 Create a raster surface dataset from the feature points. a) Import points from [MN.csv] to ArcMap using MAKE XY EVENT LAYER with the North American 1983 Continuously Operating Reference Station datum (GCS NAD 1983 CORS96) coordinate reference system. b) Create a raster surface with inverse distance weighting in Spatial Analyst toolbox. IDW.SpatialAnalyst(Output Cell Size=0.0001 degree; Power=2; Search Radius=Variable; Number of Points=12) to obtain [MN_raster_idw.tif]. 2019 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 polygon [mu_diss.shp] to create a clipping mask [mu_buff300m.shp]. BUFFER(Side type= Full; Method =Geodesic; Dissolve type= All). b) Clip the raster with the clipping mask. EXTRACT BY MASK to obtain [MN_ELI.tif]. 2019 Calculate values for each marsh unit. a) Clip the raster with the polygon features by using EXTRACT BY MASK to obtain [mn_idw_mu.tif]. b) ZONAL STATISTICS AS TABLE(Feature Zone Data=[mu_diss.shp]; zone field=FID_CMU; Value Raster=[mn_idw_mu.tif]; Output Table=mu; Statistics type=MEAN) c) ADD JOIN(Layer name=[mu_diss.shp]; Input join field=FID_CMU; Join Table=mu; Output join field=FID_CMU) to marsh units layer based on the "FID_CMU" field d) Export dataset as a shapefile [mu_MN_ELI.shp] and keep the 'mu_MEAN" and "mu_ATOT_M2" fields from the join operation. e) SELECT BY ATTRIBUTES FROM [CMU_ELI] where "CLASS"= 'vegetated', and join field "APGN_M2" from CMU_ELI.shp on the feature dataset [mu_MN_ELI.shp]. f) Rearrange field names and change the projection for better performance of web services with online base maps. PROJECT(Input coordinate system=NAD 1983 UTM Zone 18N; Output coordinate system=WGS 1984 Web Mercator Auxiliary Sphere; Geographic transformation=WGS 1984 (ITRF00) to NAD 1983) the feature dataset to obtain the final conceptual marsh units [mu_MN_ELI.shp]. 2019 Added keywords section with USGS persistent identifier as theme keyword. 20200806 U.S. Geological Survey VeeAnn A. Cross Marine Geologist Mailing and Physical

384 Woods Hole Road

Woods Hole MA 02543-1598 508-548-8700 x2251 508-457-2310 vatnipp@usgs.gov Version 2 updates. Updates were performed in ArcGIS Pro 2.8.8. Duplicate marsh units were manually identified and compared to make sure the most appropriate duplicate marsh unit was deleted. Seventy-six duplicate marsh units were identified (out of 2828) in Mecox Bay, Sagaponack Pond and Georgica Pond and have been removed. After the duplicate marsh units were deleted, the elevation, hydroflattened percentage and elevation flag values were recalculated. Authorship was updated to include Kate Ackerman. 20240116 Kate Ackerman U.S. Geological Survey Geologist mailing address

384 Woods Hole Road

Woods Hole MA 02543 US 508-548-8700 x2331 508-457-2310 kackerman@usgs.gov Vector G-polygon 2752 WGS 1984 Web Mercator Auxiliary Sphere (ESRI Full Name: WGS_1984_Web_Mercator_Auxiliary_Sphere) 0.0 0.0 0.0 0.0 coordinate pair 0.6096 0.6096 Meter D_WGS_1984 WGS_1984 6378137.0 298.257223563 mu_MN_ELI Table containing attribute information associated with the dataset. U.S. Geological Survey FID Internal feature number. Esri Unique whole numbers that are automatically generated. Shape Feature geometry. Esri Coordinates defining the features. FID_CMU Unique whole number that represents the identification number for each conceptual marsh unit. USGS 2 3455 none ATOT_M2 Total surface area of a marsh unit in square meters USGS 8.876088 1278469.79671 square meters AVEG_M2 Surface area of vegetated part of a marsh unit in square meters. Value is set to -9999 if there is no vegetated area in the marsh unit. USGS 0 1189344.84656 square meters MN Mean tidal range in meters averaged over a marsh unit USGS 0.612894 1.607883 meters FLG Marsh unit flag indicating anomalous marsh units based on elevation, surface area, and absence of vegetation. FLG values indicate: (-1) no vegetated area; (-10) marsh unit elevation higher than the 99.8 percentile; (-100) marsh unit elevation less than 0.2 percentile; (-200) greater than 25% of marsh unit has hydroflattened area (and has -9999 as its elevation value; (-1000) marsh unit surface area less than 900 m2; and (0) no flag. Combination of negative values indicate combination of flags. For example, -1001 indicates no vegetated area and area less than 900 m2. USGS -11201 0 None In this dataset, tidal range for each conceptual salt marsh unit in the eastern Long Island salt marsh complex has been calculated based on a 0.0005 arc degrees interpolated VDatum dataset. Decimal values in the attribute table are a result of double precision calculations while significant digits are considered in defining the attribute measurement resolutions. Therefore, the smallest unit increment for area values and tidal range is assumed to be 1 meter and 0.01, respectively. USGS U.S. Geological Survey - ScienceBase mailing and physical address

Denver Federal Center, Building 810, Mail Stop 302

Denver CO 80225 1-888-275-8747 sciencebase@usgs.gov mu_MN_ELI.shp (and other shapefile components), browse graphic, and CSDGM metadata in XML format. 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. shapefile ArcGIS Pro 2.8.8 This dataset contains a polygon shapefile and its components and metadata in xml format. https://www.sciencebase.gov/catalog/file/get/5ddd8803e4b04a30051ac1d6 https://www.sciencebase.gov/catalog/item/5ddd8803e4b04a30051ac1d6 https://doi.org/10.5066/P91H426U The first link in network resources is to download data directly. The second link points to a landing page with metadata and data. The third link is to the main page of the data release. WMS https://www.sciencebase.gov/catalogMaps/mapping/ows/5ddd8803e4b04a30051ac1d6?service=wms&request=getcapabilities&version=1.3.0 The link in network resources points to the Web Mapping Services (WMS) end point. WFS https://www.sciencebase.gov/catalogMaps/mapping/ows/5ddd8803e4b04a30051ac1d6?service=wfs&request=getcapabilities&version=1.0.0 The link in network resources points to the Web Feature Services (WFS) end point. None. No fees are applicable for obtaining the data set. 20240312 U.S. Geological Survey, Northeast Region Robert J Welk Hydrologic Technician mailing address

2045 Route 112

Coram NY 11727 US 631-736-0783 x141 whsc_data_contact@usgs.gov The metadata contact email address is a generic address in the event the person is no longer with USGS. FGDC Content Standard for Digital Geospatial Metadata FGDC-STD-001-1998