Elevation of marsh units in Connecticut salt marshes

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Metadata:

Identification_Information:
Citation:
Citation_Information:
Originator: Kate V. Ackerman
Originator: Zafer Defne
Originator: Neil K. Ganju
Publication_Date: 20231023
Title: Elevation of marsh units in Connecticut salt marshes
Edition: 1.0
Geospatial_Data_Presentation_Form: vector digital dataset (polygon)
Series_Information:
Series_Name: data release
Issue_Identification: DOI:10.5066/P96QND48
Publication_Information:
Publication_Place: Woods Hole Coastal and Marine Science Center, Woods Hole, MA
Publisher:
U.S. Geological Survey, Coastal and Marine Hazards and Resources Program
Online_Linkage: https://doi.org/10.5066/P96QND48
Online_Linkage:
https://www.sciencebase.gov/catalog/item/64c408c2d34e70357a33d422
Larger_Work_Citation:
Citation_Information:
Originator: Kate V. Ackerman
Originator: Zafer Defne
Originator: Neil K. Ganju
Publication_Date: 2023
Title: Geospatial characterization of salt marshes in Connecticut
Edition: 1.0
Geospatial_Data_Presentation_Form: vector digital data
Series_Information:
Series_Name: data release
Issue_Identification: DOI:10.5066/P96QND48
Publication_Information:
Publication_Place: Reston, VA
Publisher: U.S. Geological Survey
Other_Citation_Details:
Suggested citation: Ackerman, K.V., Defne, Z., and Ganju, N.K., 2023, Geospatial characterization of salt marshes in Connecticut: U.S. Geological Survey data release, https://doi.org/10.5066/P96QND48.
Online_Linkage: https://doi.org/10.5066/P96QND48
Online_Linkage:
https://www.sciencebase.gov/catalog/item/64c406bdd34e70357a33d413
Description:
Abstract:
This data release contains coastal wetland synthesis products for the state of Connecticut. Metrics for resiliency, including the unvegetated to vegetated ratio (UVVR), marsh elevation, tidal range, wave power, and exposure potential to environmental health stressors are calculated for smaller units delineated from a digital elevation model, providing the spatial variability of physical factors that influence wetland health. 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. This project has been funded in part by the United States Environmental Protection Agency under assistance agreement DW-014-92531201-1 to N. Ganju.
Purpose:
The purpose of this shapefile is to calculate the mean elevation for each marsh unit and its vegetated component. Analysis of marsh elevation is part of a comprehensive assessment to identify the factors and their weights in determining the vulnerability and resiliency of salt marshes. Elevation distribution in Connecticut salt marshes is given in terms of mean elevation of conceptual marsh units, as well as the vegetated portion of the marsh unit. The elevation data is based on the 1-meter 2016 CT Lidar DEM.
Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: 2023
Currentness_Reference: publication date
Status:
Progress: Complete
Maintenance_and_Update_Frequency: None
Spatial_Domain:
Bounding_Coordinates:
West_Bounding_Coordinate: -73.658477
East_Bounding_Coordinate: -71.831904
North_Bounding_Coordinate: 41.532199
South_Bounding_Coordinate: 40.983874
Keywords:
Theme:
Theme_Keyword_Thesaurus: ISO 19115 Topic Category
Theme_Keyword: oceans
Theme_Keyword: inlandWaters
Theme_Keyword: environment
Theme_Keyword: elevation
Theme:
Theme_Keyword_Thesaurus: USGS Thesaurus
Theme_Keyword: geospatial datasets
Theme_Keyword: wetland ecosystems
Theme_Keyword: wetland functions
Theme_Keyword: coastal ecosystems
Theme_Keyword: coastal processes
Theme_Keyword: vegetation
Theme:
Theme_Keyword_Thesaurus: None
Theme_Keyword: salt marsh
Theme_Keyword: marsh health
Theme_Keyword: estuary
Theme_Keyword: elevation
Theme:
Theme_Keyword_Thesaurus: USGS Metadata Identifier
Theme_Keyword: USGS:64c408c2d34e70357a33d422
Place:
Place_Keyword_Thesaurus: None
Place_Keyword: United States
Place_Keyword: Connecticut
Place_Keyword: Long Island Sound
Access_Constraints: None
Use_Constraints:
The mean elevation 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.
Point_of_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: Kate Ackerman
Contact_Organization: U.S. Geological Survey
Contact_Position: Geologist
Contact_Address:
Address_Type: mailing address
Address: 384 Woods Hole Road
City: Woods Hole
State_or_Province: MA
Postal_Code: 02543
Country: US
Contact_Voice_Telephone: 508-548-8700 x2331
Contact_Facsimile_Telephone: 508-457-2310
Contact_Electronic_Mail_Address: kackerman@usgs.gov
Browse_Graphic:
Browse_Graphic_File_Name:
https://www.sciencebase.gov/catalog/file/get/64c408c2d34e70357a33d422/?name=Elev_CT_Browse.png&allowOpen=true
Browse_Graphic_File_Description:
Graphic that shows elevation of conceptual marsh units in Connecticut salt marshes.
Browse_Graphic_File_Type: PNG
Native_Data_Set_Environment:
Environment as of Metadata Creation: Microsoft Windows 10; Esri ArcGIS Pro (version 2.8.8)
Data_Quality_Information:
Attribute_Accuracy:
Attribute_Accuracy_Report:
Marsh units and water and land boundaries inherit their horizontal accuracy from the accuracy of the source data, the conceptual marsh units, and their vertical accuracy from the elevation dataset (1-meter 2016 CT Lidar DEM).
Logical_Consistency_Report:
Positive elevation indicates above sea level. Marsh units with extremely low elevation (smaller than the 0.2 percentile value), extremely high elevation (larger than the 99.8 percentile value) or areas less than 900 square meters were flagged in the dataset.
Completeness_Report:
The marsh polygons are bound to the borders of Connecticut's estuarine intertidal areas that include: 1) emergent wetlands, 2) scrub-shrub areas, 3) rooted vascular aquatic beds, 4) organic unconsolidated shores, and 5) channels of open water that are narrower than 10 meters. Occasionally, marsh units are retained in this dataset even though the imagery displayed extreme change (e.g., partially or completely converted to water) from the NWI wetland delineation (e.g., marsh units 2172, 2402). In a few areas, there are no marsh units where there is visible marsh plain (e.g., northwest of marsh unit 1682), because the areas are classified in the NWI as estuarine intertidal unconsolidated shore, which is not included in our salt marsh boundaries. In a few locations, there may be areas that that are classified as unvegetated but are in fact very sparsely vegetated. A detailed on-the-ground analysis of a single site may result in a different interpretation of the wetland and marsh unit boundaries than those established through this analysis.
Positional_Accuracy:
Horizontal_Positional_Accuracy:
Horizontal_Positional_Accuracy_Report:
Horizontal accuracy for the polygon boundaries is inherited from the source layer, the conceptual marsh units, and is considered to be +/- 6 meters.
Vertical_Positional_Accuracy:
Vertical_Positional_Accuracy_Report:
Because the elevation values are averaged over delineated polygons, vertical accuracy depends on both the horizontal accuracy of the NWI dataset and the vertical accuracy of the source elevation dataset (1-meter 2016 CT Lidar DEM). The vertical accuracy is inherited from the source elevation dataset; it is reported to be 0.06 meters. No additional accuracy assessment of the vertical accuracy has been conducted.
Lineage:
Source_Information:
Source_Citation:
Citation_Information:
Originator: Capitol Region Council of Governments
Publication_Date: 2017
Title: Connecticut Statewide Lidar 2016
Edition: First
Geospatial_Data_Presentation_Form: raster digital dataset
Publication_Information:
Publication_Place: Connecticut
Publisher: State of Connecticut
Other_Citation_Details:
Downloaded 1-meter 2016 Lidar DEM. Projection was NAD 1983 UTM Zone 18N with the North American Vertical Datum of 1988 (NAVD88). Download date was 07/30/2021.
Online_Linkage: https://www.fisheries.noaa.gov/inport/item/49408
Type_of_Source_Media: Digital
Source_Time_Period_of_Content:
Time_Period_Information:
Range_of_Dates/Times:
Beginning_Date: 20160311
Ending_Date: 20160416
Source_Currentness_Reference: ground condition
Source_Citation_Abbreviation: CT DEM
Source_Contribution: Elevation dataset
Source_Information:
Source_Citation:
Citation_Information:
Originator: K.V. Ackerman
Originator: Z. Defne
Originator: N.K. Ganju
Publication_Date: 2023
Title:
Conceptual marsh units of Connecticut salt marshes in Geospatial characterization of salt marshes in Connecticut
Edition: 1.0
Geospatial_Data_Presentation_Form: vector digital dataset (polygon)
Series_Information:
Series_Name: data release
Issue_Identification: DOI:10.5066/P96QND48
Publication_Information:
Publication_Place: Reston, VA
Publisher: U.S. Geological Survey
Other_Citation_Details:
This dataset (Conceptual marsh units of Connecticut salt marshes) is within the larger data release (Geospatial characterization of salt marshes in Connecticut). The first link below is to the conceptual marsh units data and the second link is to the data release.
Online_Linkage:
https://www.sciencebase.gov/catalog/item/64c40893d34e70357a33d41f
Online_Linkage: https://doi.org/10.5066/P96QND48
Type_of_Source_Media: Digital
Source_Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: 2023
Source_Currentness_Reference: publication date
Source_Citation_Abbreviation: CMU_CT
Source_Contribution:
Used conceptual marsh units, generated as part of this data release, to delineate marsh unit boundaries and areas of vegetation.
Process_Step:
Process_Description:
This process step and all subsequent process steps were performed by the same person, Kate Ackerman, in ArcGIS Pro (ver. 2.8.8), unless otherwise stated. For simple operations the name of the geoprocessing tool used is given in capital letters; for complex operations, the name of 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 unless otherwise stated.
a) Set the data frame coordinate system and projection to NAD 1983 UTM Zone 18N (2011).
b) Establish marsh unit boundaries. Dissolve the vegetated and unvegetated classes in each marsh unit to have only one class for each marsh unit. DISSOLVE (Input features=[CMU_CT.shp]; Dissolve field=FID_CMU; Statistics field=ATOT_M2 and FLG with Statistics type= First). PROJECT (Input coordinate system=WGS 1984 Web Mercator Auxiliary Sphere; Output coordinate system=NAD 1983 UTM Zone 18N (2011)) the feature dataset to obtain dissolved marsh units [mu_diss.shp].
c) Prepare elevation dataset. Combine all downloaded tiles into one raster, using MOSAIC TO NEW RASTER, and PROJECT RASTER to NAD 1983 UTM Zone 18N (2011).
d) Create a polygon that covers the area of interest [extent.shp]. CLIP the mosaicked elevation dataset created in step (c) by [extent.shp] to create [elev_mosaic.tif].
Source_Used_Citation_Abbreviation: CT DEM
Source_Used_Citation_Abbreviation: CMU_CT
Process_Date: 2022
Source_Produced_Citation_Abbreviation: elev_mosaic.tif
Source_Produced_Citation_Abbreviation: mu_diss.shp
Process_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: Kate Ackerman
Contact_Organization: U.S. Geological Survey
Contact_Position: Geologist
Contact_Address:
Address_Type: mailing address
Address: 384 Woods Hole Road
City: Woods Hole
State_or_Province: MA
Postal_Code: 02543
Country: US
Contact_Voice_Telephone: 508-548-8700 x2331
Contact_Facsimile_Telephone: 508-457-2310
Contact_Electronic_Mail_Address: kackerman@usgs.gov
Process_Step:
Process_Description:
a) Remove pixels from elevation raster that are hydro-flattened. Use FOCAL STATISTICS (Input raster=[elev_mosaic.tif], Output raster=[FocalStats_3x3_range.tif], Neighborhood settings=3x3 cell, Statistics type=range) and RASTER CALCULATOR to identify (Map algebra expression: Con("%FocalStats_3x3_range.tif%" == 0,-1,1); Output raster=[elev_mosaic_One_NegOne.tif]) and remove (Map algebra expression: SetNull("%elev_mosaic_One_NegOne.tif%", "%elev_mosaic.tif%", "value = -1"); Output raster=[elev_mosaic_noHF.tif]) all hydro-flattened areas from [elev_mosaic.tif] to create [elev_mosaic_noHF.tif].
b) Calculate the mean elevation for each marsh unit with ZONAL STATISTICS AS TABLE (Feature zone data=[mu_diss.shp], Zone field=FID_CMU; Input value raster=[elev_mosaic_noHF.tif]; Statistics type=Mean; Output table=[mu]; Ignore Nodata=True). JOIN mean elevation from [mu] table to marsh units layer [mu_diss.shp] based on the "FID_CMU" field. Export dataset as a shapefile [mu_elev.shp]. Rename "mu_MEAN" to "MU_ELEV."
c) Calculate the percent of the marsh unit that has hydro-flattened area. ZONAL STATISTICS AS TABLE (Feature zone data=[mu_elev.shp], Zone field=FID_CMU; Input value raster=[elev_mosaic_One_NegOne.tif]; Statistics type=Mean; Output table=[zs_muelev_HF]; Ignore Nodata=True). ADD FIELD to the output table to calculate hydro-flattened area of each marsh unit (MU_HFAR), CALCULATE FIELD (MU_HFAR= (1-MEAN)/2). JOIN MU_HFAR field to [mu_elev.shp]. If the percent hydro-flattened area is greater than 25 percent, set the marsh unit elevation to -9999.
d) Calculate the elevation of the vegetated area of the marsh unit. SELECT BY ATTRIBUTES from [CMU_CT.shp] where "TYP"= 'vegetated', output: [CMU_CT_VEG.shp]. ZONAL STATISTICS AS TABLE (Feature zone data=[CMU_CT_VEG.shp], Zone field=FID_CMU; Input value raster=[elev_mosaic_noHF.tif]; Statistics type=Mean; Output table=[vg]; Ignore Nodata=True). Join the mean elevation of the vegetated portion to [mu_elev.shp] and rename the field to "VG_ELEV."
e) Calculate the percent of the vegetated portion of the marsh unit that has hydro-flattened area. ZONAL STATISTICS AS TABLE (Feature zone data=[CMU_CT_VEG.shp], Zone field=FID_CMU; Input value raster=[elev_mosaic_One_NegOne.tif]; Statistics type=Mean; Output table=[zs_muelev_HF]; Ignore Nodata=True). ADD FIELD (VG_HFAR) to output table, CALCULATE FIELD (VG_HFAR= (1-MEAN)/2). Join VG_HFAR field to [mu_elev.shp]. If the percent hydro-flattened area is greater than 25 percent, set the vegetated elevation to -9999.
f) JOIN the vegetated area (AVEG_M2) from [CMU_CT_VEG.shp] to [mu_elev.shp].
Source_Used_Citation_Abbreviation: elev_mosaic.tif
Process_Date: 2022
Source_Produced_Citation_Abbreviation: mu_elev.shp
Process_Step:
Process_Description:
a) Run Python script (marsv5.py) in ArcGIS Pro (v.2.8.8) to calculate metrics that quantify the distribution of marsh unit elevation values. Skewness ("SKWNSS") is the measure of asymmetry of the elevation distribution in the vegetated part of a marsh unit. Positive skewness values, i.e. right-skewed distributions, indicate clustering of elevation distributions towards lower elevations. Negative skewness values indicate a left-skewed distribution and clustering towards higher elevations. Lower third ("LOW3RD") is the percent of elevation values that fall within the lowest third of the elevation range within the vegetated part of a marsh unit. SKWNSS and LOW3RD parameters are calculated by applying the formulation of Raposa et al. (2016) to the elevation raster within the vegetated part of each marsh unit. JOIN these values to [mu_elev.shp]. If VG_ELEV= -9999, set SKWNESS and LOW3RD values to -9999. Export to a new shapefile [mu_elev_CT.shp].
Reference: Raposa, K. B., Wasson, K., Smith, E., Crooks, J. A., Delgado, P., Fernald, S. H., et al. (2016). Assessing tidal marsh resilience to sea-level rise at broad geographic scales with multi-metric indices. Biological Conservation, 204, 263–275. https://doi.org/10.1016/J.BIOCON.2016.10.015.
Source_Used_Citation_Abbreviation: mu_elev.shp
Process_Date: 2022
Source_Produced_Citation_Abbreviation: mu_elev_CT.shp
Process_Step:
Process_Description:
a) Add field "FLG" to flag anomalous marsh units based on absence of vegetation, elevation, surface area, and tidal range extrapolation. The flags are calculated in their respective shapefile (i.e., elevation flags are calculated in the elevation shapefile). Set FLG to: (-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 square meters; (-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 square meters.
b) Rearrange fields and change the projection for better performance of web services with online base maps. PROJECT (Output coordinate system=WGS 1984 Web Mercator Auxiliary Sphere) the feature dataset to obtain the final elevation dataset [mu_elev_CT.shp].
Process_Date: 2022
Source_Produced_Citation_Abbreviation: mu_elev_CT.shp
Spatial_Data_Organization_Information:
Direct_Spatial_Reference_Method: Vector
Point_and_Vector_Object_Information:
SDTS_Terms_Description:
SDTS_Point_and_Vector_Object_Type: G-polygon
Point_and_Vector_Object_Count: 2499
Spatial_Reference_Information:
Horizontal_Coordinate_System_Definition:
Planar:
Map_Projection:
Map_Projection_Name:
WGS 1984 Web Mercator Auxiliary Sphere (Esri full name: WGS_1984_Web_Mercator_Auxiliary_Sphere)
Map_Projection_Parameters:
False_Easting: 0.0
False_Northing: 0.0
Longitude_of_Central_Meridian: 0.0
Standard_Parallel: 0.0
Planar_Coordinate_Information:
Planar_Coordinate_Encoding_Method: coordinate pair
Coordinate_Representation:
Abscissa_Resolution: 0.6096
Ordinate_Resolution: 0.6096
Planar_Distance_Units: meters
Geodetic_Model:
Horizontal_Datum_Name: D_WGS_1984
Ellipsoid_Name: WGS 84
Semi-major_Axis: 6378137.0
Denominator_of_Flattening_Ratio: 298.257223563
Entity_and_Attribute_Information:
Detailed_Description:
Entity_Type:
Entity_Type_Label: mu_elev_CT.shp
Entity_Type_Definition:
Table containing attribute information associated with the dataset.
Entity_Type_Definition_Source: USGS
Attribute:
Attribute_Label: FID
Attribute_Definition: Internal feature number.
Attribute_Definition_Source: Esri
Attribute_Domain_Values:
Unrepresentable_Domain:
Sequential unique whole numbers that are automatically generated.
Attribute:
Attribute_Label: Shape
Attribute_Definition: Feature geometry.
Attribute_Definition_Source: Esri
Attribute_Domain_Values:
Unrepresentable_Domain: Feature geometry. Marsh units are polygon features.
Attribute:
Attribute_Label: FID_CMU
Attribute_Definition:
Unique whole numbers used to identify each conceptual marsh unit.
Attribute_Definition_Source: USGS
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0
Range_Domain_Maximum: 2498
Attribute_Units_of_Measure: none
Attribute:
Attribute_Label: ATOT_M2
Attribute_Definition: Total surface area of a marsh unit.
Attribute_Definition_Source: USGS
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 164.768742142
Range_Domain_Maximum: 511079.279508
Attribute_Units_of_Measure: square meters
Attribute:
Attribute_Label: AVEG_M2
Attribute_Definition: Surface area of the vegetated part of a marsh unit.
Attribute_Definition_Source: USGS
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.0
Range_Domain_Maximum: 476006.471534
Attribute_Units_of_Measure: square meters
Attribute:
Attribute_Label: MU_ELEV
Attribute_Definition:
Mean elevation of a marsh unit. If the percent hydro-flattened area is greater than 25 percent (MU_HFAR is greater than 0.25), the marsh unit elevation is set to -9999 indicating insufficient elevation data.
Attribute_Definition_Source: USGS
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: -0.820701
Range_Domain_Maximum: 8.35128021
Attribute_Units_of_Measure: meters
Attribute:
Attribute_Label: VG_ELEV
Attribute_Definition:
Mean elevation of the vegetated area in a marsh unit. If there is no vegetated area in the marsh unit, the value is set to -9999. Also, if the percent hydro-flattened area in the vegetated portion is greater than 25 percent (VG_HFAR is greater than 0.25), the value is set to -9999 indicating insufficient elevation data.
Attribute_Definition_Source: USGS
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: -0.579696081076
Range_Domain_Maximum: 8.35486141855
Attribute_Units_of_Measure: meters
Attribute:
Attribute_Label: MU_HFAR
Attribute_Definition:
Percent (in decimal form) of the marsh unit that contains hydro-flattened bathymetric/elevation values.
Attribute_Definition_Source: USGS
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0
Range_Domain_Maximum: 1
Attribute_Units_of_Measure: none
Attribute:
Attribute_Label: VG_HFAR
Attribute_Definition:
Percent (in decimal form) of the vegetated portion of the marsh unit that contains hydro-flattened bathymetric/elevation values. If there is no vegetated area in the marsh unit, the value is set to -9999.
Attribute_Definition_Source: USGS
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0
Range_Domain_Maximum: 1
Attribute_Units_of_Measure: none
Attribute:
Attribute_Label: SKWNSS
Attribute_Definition:
The measure of skewness of the elevation distribution in the vegetated part of a marsh unit. Positive skewness values (i.e., right-skewed distribution) indicate clustering of elevation distribution towards lower elevations. Negative values (left-skewed distribution) indicate clustering towards higher elevations. A value of -9999 indicates no vegetated area within the marsh unit or no elevation value for the vegetated portion.
Attribute_Definition_Source: USGS
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: -5.96721983
Range_Domain_Maximum: 8.8347702
Attribute_Units_of_Measure: none
Attribute:
Attribute_Label: LOW3RD
Attribute_Definition:
LOW3RD is the percent of elevation values that fall within the lowest third of the elevation range within the vegetated part of a marsh unit. Value of -9999 indicates no vegetated area within the marsh unit or no elevation value for the vegetated portion.
Attribute_Definition_Source: USGS
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: 0.0178333
Range_Domain_Maximum: 99.85710144
Attribute_Units_of_Measure: none
Attribute:
Attribute_Label: FLG
Attribute_Definition:
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 square meters; (-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 square meters.
Attribute_Definition_Source: USGS
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: -11200
Range_Domain_Maximum: 0
Attribute_Units_of_Measure: none
Overview_Description:
Entity_and_Attribute_Overview:
In this dataset, mean elevation for each conceptual salt marsh unit in Connecticut salt marshes has been calculated based on the 1-meter 2016 CT Lidar DEM source 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 and elevation values is assumed to be 1 meter and 0.01 meter, respectively.
Entity_and_Attribute_Detail_Citation: USGS
Distribution_Information:
Distributor:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: U.S. Geological Survey - ScienceBase
Contact_Address:
Address_Type: mailing and physical address
Address: Denver Federal Center, Building 810, Mail Stop 302
City: Denver
State_or_Province: CO
Postal_Code: 80225
Contact_Voice_Telephone: 1-888-275-8747
Contact_Electronic_Mail_Address: sciencebase@usgs.gov
Resource_Description:
mu_elev_CT.zip (ZIP file contains the shapefile mu_elev_CT.shp and the additional shapefile components), browse graphic (Elev_CT_Browse.png), and FGDC CSDGM metadata in xml format.
Distribution_Liability:
Although these data have been processed successfully on a computer system at 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. 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. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government. The contents of this document do not necessarily reflect the views and policies of the Environmental Protection Agency. Not for navigational use.
Standard_Order_Process:
Digital_Form:
Digital_Transfer_Information:
Format_Name: shapefile
Format_Version_Number: ArcGIS Pro 2.8.8
Format_Information_Content:
This dataset contains a polygon shapefile and its components and metadata in xml format.
Transfer_Size: 7
Digital_Transfer_Option:
Online_Option:
Computer_Contact_Information:
Network_Address:
Network_Resource_Name:
https://www.sciencebase.gov/catalog/file/get/64c408c2d34e70357a33d422
Network_Resource_Name:
https://www.sciencebase.gov/catalog/item/64c408c2d34e70357a33d422
Network_Resource_Name: https://doi.org/10.5066/P96QND48
Access_Instructions:
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.
Digital_Form:
Digital_Transfer_Information:
Format_Name: WMS
Digital_Transfer_Option:
Online_Option:
Computer_Contact_Information:
Network_Address:
Network_Resource_Name:
https://www.sciencebase.gov/catalogMaps/mapping/ows/64c408c2d34e70357a33d422?service=wms&request=getcapabilities&version=1.3.0
Access_Instructions:
The link in network resources points to the Web Mapping Services (WMS) end point.
Digital_Form:
Digital_Transfer_Information:
Format_Name: WFS
Digital_Transfer_Option:
Online_Option:
Computer_Contact_Information:
Network_Address:
Network_Resource_Name:
https://www.sciencebase.gov/catalogMaps/mapping/ows/64c408c2d34e70357a33d422?service=wfs&request=getcapabilities&version=1.0.0
Access_Instructions:
The link in network resources points to the Web Feature Service (WFS) end point.
Fees: None. No fees are applicable for obtaining the dataset.
Metadata_Reference_Information:
Metadata_Date: 20231023
Metadata_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: Kate V. Ackerman
Contact_Organization: U.S. Geological Survey
Contact_Position: Geologist
Contact_Address:
Address_Type: mailing address
Address: 384 Woods Hole Rd
City: Woods Hole
State_or_Province: MA
Postal_Code: 02543
Country: US
Contact_Voice_Telephone: 508-548-8700 x2331
Contact_Facsimile_Telephone: 508-457-2310
Contact_Electronic_Mail_Address: 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_Name: Content Standard for Digital Geospatial Metadata
Metadata_Standard_Version: FGDC-STD-001-1998
This page is <https://cmgds.marine.usgs.gov/catalog/whcmsc/SB_data_release/DR_P96QND48/mu_elev_CT.html>
Generated by mp version 2.9.51 on Mon Oct 23 17:02:49 2023