Metadata: Identification_Information: Citation: Citation_Information: Originator: Zafer Defne Originator: Neil K. Ganju Publication_Date: 20220526 Title: Lifespan of marsh units in Assateague Island National Seashore and Chincoteague Bay, Maryland and Virginia Edition: 1.0 Geospatial_Data_Presentation_Form: Vector Digital Data Set (Polygon) Series_Information: Series_Name: data release Issue_Identification: DOI:10.5066/P9WSYCAN Publication_Information: Publication_Place: Woods Hole Coastal and Marine Science Center, Woods Hole, MA Publisher: U.S. Geological Survey, Coastal and Marine Geology Program Other_Citation_Details: Suggested citation: Ganju, N.K., and Defne, Z. 2022, Lifespan of marsh units in Assateague Island National Seashore and Chincoteague Bay, Maryland and Virginia: U.S. Geological Survey data release, https://doi.org/10.5066/P9WSYCAN. Online_Linkage: https://doi.org/10.5066/P9WSYCAN Online_Linkage: https://www.sciencebase.gov/catalog/item/6267eb10d34e76103ccf4d98 Description: Abstract: The sediment-based lifespan of salt marsh units in Assateague Island National Seashore (ASIS) and Chincoteague Bay is shown for conceptual marsh units defined by Defne and Ganju (2018). The lifespan represents the timescale by which the current sediment mass within a marsh parcel can no longer compensate for sediment export and deficits induced by sea-level rise. The lifespan calculation is based on vegetated cover, marsh elevation, sediment supply, and sea-level rise (SLR) predictions after Ganju and others (2020). Sea level rise scenarios are present day estimates corresponding to the 0.3, 0.5, and 1.0 meter increase in Global Mean Sea Level (GMSL) by 2100 from Sweet and others (2017). 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, including the Assateague Island National Seashore and Chincoteague Bay salt marshes, 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. References: Defne, Z., and Ganju, N.K., 2018, Conceptual marsh units for Assateague Island National Seashore and Chincoteague Bay, Maryland and Virginia: U.S. Geological Survey data release, https://doi.org/10.5066/P92ZW4D9. Ganju, N.K., Defne, Z., Fagherazzi, S., 2020, Are elevation and open-water conversion of salt marshes connected?, Geophysical Research Letters, https://doi.org/10.1029/2019GL086703. Sweet, W.V., Kopp, R.E., Weaver, C.P., Obeysekera, J., Horton, R.M., Thieler, E.R., and Zervas, C., 2017, Global and regional sea level rise scenarios for the United States (Tech. Rep. NOS CO-OPS 083). Silver Spring, MD: National Oceanic and Atmospheric Administration. https://doi.org/10.7289/v5/tr-nos-coops-083. Purpose: The purpose of this shapefile is to present lifespan estimates for each marsh unit in Assateague Island National Seashore and Chincoteague Bay. Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 2022 Currentness_Reference: publication date Status: Progress: Complete Maintenance_and_Update_Frequency: None Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -75.4955 East_Bounding_Coordinate: -75.0962 North_Bounding_Coordinate: 38.3377 South_Bounding_Coordinate: 37.8457 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: sea-level change Theme_Keyword: sediment transport Theme_Keyword: estuarine processes Theme: Theme_Keyword_Thesaurus: None Theme_Keyword: salt marsh Theme_Keyword: vegetation Theme_Keyword: marsh health Theme_Keyword: lifespan Theme_Keyword: estuary Theme_Keyword: Long-Term Ecological Research Theme_Keyword: LTER Theme: Theme_Keyword_Thesaurus: USGS Metadata Identifier Theme_Keyword: USGS:6267eb10d34e76103ccf4d98 Place: Place_Keyword_Thesaurus: None Place_Keyword: Atlantic Ocean Place_Keyword: United States Place_Keyword: Maryland Place_Keyword: Virginia Place_Keyword: Worcester County Place_Keyword: Accomack County Place_Keyword: Assateague Island National Seashore Place_Keyword: Assateague State Park Place_Keyword: Chincoteague Bay Place_Keyword: Chincoteague Island Place_Keyword: Wallops Island Place_Keyword: E.A. Vaughn Wildlife Management Area Access_Constraints: None Use_Constraints: The lifespan estimate 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_Organization_Primary: Contact_Organization: U.S. Geological Survey Contact_Person: Zafer Defne Contact_Position: Oceanographer Contact_Address: Address_Type: mailing and physical address Address: 384 Woods Hole Road City: Woods Hole State_or_Province: MA Postal_Code: 02543 Contact_Voice_Telephone: 508-548-8700 x2254 Contact_Facsimile_Telephone: 508-457-2310 Contact_Electronic_Mail_Address: zdefne@usgs.gov Browse_Graphic: Browse_Graphic_File_Name: https://www.sciencebase.gov/catalog/file/get/6267eb10d34e76103ccf4d98?name=mu_lifespan_ASISp.png Browse_Graphic_File_Description: Graphic of lifespan estimates under background relative sea level rise in Assateague Island and Chincoteague Bay salt marsh overlaying Esri basemap. Browse_Graphic_File_Type: PNG Native_Data_Set_Environment: Environment as of Metadata Creation: Microsoft Windows 10 Version 0.1 (Build 19042); Esri ArcGIS Pro 2.8.2 Cross_Reference: Citation_Information: Originator: Zafer Defne Originator: Neil K. Ganju Publication_Date: 2018 Title: Conceptual marsh units for Assateague Island National Seashore and Chincoteague Bay, Maryland and Virginia Edition: 1.0 Geospatial_Data_Presentation_Form: Vector Digital Data Set (Polygon) Series_Information: Series_Name: data release Issue_Identification: DOI:10.5066/P92ZW4D9 Publication_Information: Publication_Place: Reston, VA Publisher: U.S. Geological Survey Online_Linkage: https://doi.org/10.5066/P92ZW4D9 Data_Quality_Information: Attribute_Accuracy: Attribute_Accuracy_Report: Marsh units, water and land boundary inherit their accuracy from accuracy of the source data, Assateague Island marsh units, and vertical accuracy marsh unit elevation calculated from the 1-meter resolution U.S. Geological Survey Coastal National Elevation Database (USGS CoNED) data with processing date of 2016. The uncertainty in the lifespan estimates is large because of the nature of the empirical equations used and the uncertainty in the source data. For example, a 20% variation in each of the unvegetated to vegetated marsh ratio (UVVR), elevation, bulk density and sea-level rise variables contributing in the direction of reducing lifespan may result in a combined reduction of 50% in lifespan estimate. Logical_Consistency_Report: Negative lifespan indicates the estimated lifespan is depleted and loss is imminent. Flagged units (see description for the FLG variable) are assigned a lifespan estimate of -10,000. Completeness_Report: The results are specific to the marsh polygons definition within the boundaries of the Assateague Island and Chincoteague Bay 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. Coverage near the domain boundaries in Wallops Bay and Wallops Island is not complete and not suggested for use in analyses (specifically marsh units with FID_CMU= 3, 1659, 1666, 1672 and 1728). Positional_Accuracy: Horizontal_Positional_Accuracy: Horizontal_Positional_Accuracy_Report: Horizontal accuracy is inherited from the source dataset that delineates the marsh units, and can be considered to be +/-6 meters. Vertical_Positional_Accuracy: Vertical_Positional_Accuracy_Report: 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 meters. Lineage: Source_Information: Source_Citation: Citation_Information: Originator: Zafer Defne Originator: Neil K. Ganju Publication_Date: 2018 Title: Elevation of marsh units in Assateague Island National Seashore and Chincoteague Bay, Maryland and Virginia Geospatial_Data_Presentation_Form: Vector Digital Data Set (Polygon) Series_Information: Series_Name: data release Issue_Identification: DOI:10.5066/P9HCTQ66 Publication_Information: Publication_Place: Reston, VA Publisher: U.S. Geological Survey Online_Linkage: https://doi.org/10.5066/P9HCTQ66 Type_of_Source_Media: online Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 2018 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: mu_elev_ASISp.shp Source_Contribution: Used the marsh unit elevation (mu_ELEV) and vegetated fraction elevation (vg_ELEV) as inputs. Projection was WGS 1984 Web Mercator Auxiliary Sphere. Source_Information: Source_Citation: Citation_Information: Originator: Zafer Defne Originator: Neil K. Ganju Publication_Date: 2018 Title: Unvegetated to vegetated marsh ratio in Assateague Island National Seashore and Chincoteague Bay, Maryland and Virginia Geospatial_Data_Presentation_Form: Vector Digital Data Set (Polygon) Series_Information: Series_Name: data release Issue_Identification: DOI:10.5066/P9AY52YJ Publication_Information: Publication_Place: Reston, VA Publisher: U.S. Geological Survey Online_Linkage: https://doi.org/10.5066/p9ay52yj Type_of_Source_Media: online Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 2018 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: mu_UVVR_ASISp.shp Source_Contribution: Used the unvegetated to vegetated ratio (mu_UVVR) as input. Projection was WGS 1984 Web Mercator Auxiliary Sphere. Process_Step: Process_Description: This process step and subsequent process steps were performed by the same person, Zafer Defne, in ArcGIS Pro (ver.2.8.2) 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. a) Download elevation and unvegetated to vegetated marsh ratio (UVVR) datasets for Assateague Island National Seashore and Chincoteague Bay, Maryland and Virginia from the USGS ScienceBase (https://doi.org/10.5066/P9HCTQ66 and https://doi.org/10.5066/P9AY52YJ, respectively). b) Convert the coordinate system to the North American Datum of 1983 (NAD 1983) geographic coordinate system and add the coordinates for polygon centroids to the data table using ADD_GEOMETRY_ATTRIBUTES tool. c) Export following variables to a comma separated values file [ASIS_life.csv]: X_POINT, Y_POINT, FID_CMU, UVVR, ATOT_M2, AVEG_M2, mu_ELEV, vg_ELEV. Source_Used_Citation_Abbreviation: mu_elev_ASISp.shp Source_Used_Citation_Abbreviation: mu_UVVR_ASISp.chp Process_Date: 2022 Source_Produced_Citation_Abbreviation: ASIS_life.csv Process_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey Contact_Person: Zafer Defne Contact_Position: Oceanographer Contact_Address: Address_Type: mailing and physical address Address: 384 Woods Hole Road City: Woods Hole State_or_Province: MA Postal_Code: 02543 Contact_Voice_Telephone: 508-548-8700 x2254 Contact_Facsimile_Telephone: 508-457-2310 Contact_Electronic_Mail_Address: zdefne@usgs.gov Process_Step: Process_Description: The following processing stepswereperformed by Neil Ganju using VDatum online (VDatum ver.3.9) and Matlab (ver.2018a). a) Convert elevations from the North American Vertical Datum of 1988 (NAVD88)to Mean Tide Level (MTL) referenced elevations. Upload the ASCII file of latitude and longitude coordinates and elevation to VDatum online , and transform vertical datum from the NAVD88 to MTL. Do this for the marsh unit elevation and elevation of the vegetated part of the marsh unit to calculate mu_ELEV_MTL and vg_ELEV_MTL, respectively. Use value from the nearest Vdatum point for any point where VDatum has no data. b) Calculate sediment budget from UVVR based on Ganju and others (2020) with SB= -0.416*log(UVVR)-1.0749, where SB is sediment budget in kilograms per square meter per year, and log() indicates natural logarithm function. c) Calculate total sediment flux with SF= SB*ATOT_M2, where SF is sediment flux in kilograms per year and ATOT_M2 is total surface area of marsh unit in square meters. d) Calculate sediment flux for the three scenarios considered: Global mean sea level rise of 0.3 meters, 0.5 meters and 1.0 meters by year 2100. Sea-level rise (SLR) reduces vegetated marsh area, therefore, causes reduction in sediment flux. The sediment flux under SLR is calculated with SF_SLR= (SB-(GMSLR-BGRND_RSLR)*RHO_F)*ATOT_M2, where SF_SLR is sediment flux under SLR, RHO_F is dry bulk density of future deposited sediment, GMSLR is the local SLR in meters for a specific global mean sea level rise scenario, and BGRND_RSLR is the non-climatic background relative sea level rise in meters. RHO_F was assigned 159 kilograms per cubic meters from Morris and others (2016). For sea level rise projections, the averages of values from two stations (LEWES and KIPTOPEKE) from Sweet and others (2017) were used: 0.00175 meters for BGRND_RSLR, 0.0051, 0.0066, and 0.0132 meters for GMSLR of 0.3, 05. and 1.0 meters by 2100. e) Total sediment mass in the vegetated plain above MTL is calculated with TS= vg_ELEV_MTL*AVEG_M2*RHO_E, where TS is total sediment mass, AVEG_M2 is the surface area of the vegetated part of the marsh unit and RHO_E is the dry bulk density of existing marsh substrate sediment. RHO_E was assigned 373 kilograms per cubic meters from Morris and others (2016). f) Calculate lifespan (in years) for the background relative SLR with the equation BGRND= -TS/SF. Calculate lifespan (in years) under the global mean sea level rise by 0.3 meters, 0.5 meters and 1.0 meters by year 2100 scenarios with the equation GMSL= -TS/SF_SLR for each scenario (GMSL03, GMSL05, GMSL10, respectively). g) Save results as a Matlab data file [ASIS_life.mat]. References: Morris, J.T., Barber, D.C., Callaway, J.C., Chambers, R., Hagen, S.C., Hopkinson, C.S., Johnson, B.J., Megonigal, P., Neubauer, S.C., Troxler, T., and Wigand, C., 2016. Contributions of organic and inorganic matter to sediment volume and accretion in tidal wetlands at steady state. Earth's future, 4(4), 110–121. https://doi.org/10.1002/2015EF000334 Sweet, W.V., Kopp, R.E., Weaver, C.P., Obeysekera, J., Horton, R.M., Thieler, E.R., and Zervas, C., 2017, Global and regional sea level rise scenarios for the United States (Tech. Rep. NOS CO-OPS 083). Silver Spring, MD: National Oceanic and Atmospheric Administration. https://doi.org/10.7289/v5/tr-nos-coops-083. Source_Used_Citation_Abbreviation: ASIS_life.csv Process_Date: 2022 Source_Produced_Citation_Abbreviation: ASIS_life.mat Process_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey Contact_Person: Neil K. Ganju Contact_Position: Research Oceanographer Contact_Address: Address_Type: mailing and physical address Address: 384 Woods Hole Road City: Woods Hole State_or_Province: MA Postal_Code: 02543 Contact_Voice_Telephone: 508-548-8700 x2252 Contact_Facsimile_Telephone: 508-457-2310 Contact_Electronic_Mail_Address: nganju@usgs.gov Process_Step: Process_Description: The rest of the processing steps were done by Zafer Defne, in ArcGIS Pro (ver.2.8.2) and Matlab (ver.2011b) unless otherwise stated. a) Output Matlab data as a comma separated text file and merge with the marsh units features using ADD_JOIN and join filed as FID_CMU. b) For marshes that are more stable, lifespan calculation sometimes results in large numbers that are far beyond the lifespan horizon of interest. Also, positive sediment budget implies unlimited lifespan. For these units, set the maximum lifespan value to 10,000 years. c) Set lifespan values for flagged units (FLG less than 0) to -9999 so that they can be labeled as not available or excluded while plotting the data. d) Set label for lifespan values less than 0 as imminent. e) 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 lifespan values [mu_lifespan_ASISp.shp]. Source_Used_Citation_Abbreviation: ASIS_life.mat Process_Date: 2022 Source_Produced_Citation_Abbreviation: mu_lifespan_ASISp.shp Process_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey Contact_Person: Zafer Defne Contact_Position: Oceanographer Contact_Address: Address_Type: mailing and physical address Address: 384 Woods Hole Road City: Woods Hole State_or_Province: MA Postal_Code: 02543 Contact_Voice_Telephone: 508-548-8700 x2254 Contact_Facsimile_Telephone: 508-457-2310 Contact_Electronic_Mail_Address: zdefne@usgs.gov 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: 3352 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) Mercator: Standard_Parallel: 0.0 Longitude_of_Central_Meridian: 0.0 False_Easting: 0.0 False_Northing: 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_1984 Semi-major_Axis: 6378137.0 Denominator_of_Flattening_Ratio: 298.257223563 Entity_and_Attribute_Information: Detailed_Description: Entity_Type: Entity_Type_Label: mu_lifespan_ASISp attribute table Entity_Type_Definition: Attribute information associated with the lifespan estimates for the conceptual marsh units of Assateague Island and Chincoteague Bay salt marsh complex. 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: Coordinates defining the features. Attribute: Attribute_Label: FID_CMU Attribute_Definition: Sequential unique whole number that represents the identification number for each conceptual marsh units. Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0 Range_Domain_Maximum: 3351 Attribute_Units_of_Measure: none Attribute: Attribute_Label: ATOT_M2 Attribute_Definition: Total surface area of a marsh unit in square meters. Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 199.285435731 Range_Domain_Maximum: 623041.914617 Attribute_Units_of_Measure: square meter Attribute: Attribute_Label: AVEG_M2 Attribute_Definition: Surface area of vegetated part of a marsh unit in square meters. Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0.0 Range_Domain_Maximum: 479882.968935 Attribute_Units_of_Measure: square meter Attribute: Attribute_Label: mu_ELEV Attribute_Definition: Mean elevation of a marsh unit in meters referenced to NAVD88. Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: -1.269 Range_Domain_Maximum: 2.113 Attribute_Units_of_Measure: meter Attribute: Attribute_Label: mu_ELEVMTL Attribute_Definition: Mean elevation of a marsh unit in meters referenced to MTL. Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: -1.222 Range_Domain_Maximum: 2.212 Attribute_Units_of_Measure: meter Attribute: Attribute_Label: vg_ELEV Attribute_Definition: Mean elevation of the vegetated area in a marsh unit in meters referenced to NAVD88. Value is set to -9999 if there is no vegetated area in the marsh unit. No data value is -9999. Attribute_Definition_Source: USGS Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: -9999 Enumerated_Domain_Value_Definition: No Data Enumerated_Domain_Value_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: -1.086 Range_Domain_Maximum: 2.014 Attribute_Units_of_Measure: meter Attribute: Attribute_Label: vg_ELEVMTL Attribute_Definition: Mean elevation of the vegetated area in a marsh unit in meters referenced to MTL. Value is set to -9999 if there is no vegetated area in the marsh unit. No data value is -9999. Attribute_Definition_Source: USGS Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: -9999 Enumerated_Domain_Value_Definition: No Data Enumerated_Domain_Value_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: -1.039 Range_Domain_Maximum: 2.113 Attribute_Units_of_Measure: meter Attribute: Attribute_Label: UVVR Attribute_Definition: 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. Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: -1.0 Range_Domain_Maximum: 659.179020539 Attribute_Units_of_Measure: none Attribute: Attribute_Label: BGRND Attribute_Definition: Lifespan for a marsh unit (in years) for nonclimatic background relative sea level rise. Attribute_Definition_Source: USGS Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: -9999 Enumerated_Domain_Value_Definition: No Data Enumerated_Domain_Value_Definition_Source: USGS Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: 10000 Enumerated_Domain_Value_Definition: Value larger than or equal to 10000 Enumerated_Domain_Value_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: -1049 Range_Domain_Maximum: 10000 Attribute_Units_of_Measure: year Attribute: Attribute_Label: GMSL03 Attribute_Definition: Lifespan for a marsh unit (in years) for global mean sea level rise of 0.3 meters by 2100. Attribute_Definition_Source: USGS Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: -9999 Enumerated_Domain_Value_Definition: No Data Enumerated_Domain_Value_Definition_Source: USGS Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: 10000 Enumerated_Domain_Value_Definition: Value larger than or equal to 10000 Enumerated_Domain_Value_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: -18233 Range_Domain_Maximum: 10000 Attribute_Units_of_Measure: year Attribute: Attribute_Label: GMSL05 Attribute_Definition: Lifespan for a marsh unit (in years) for global mean sea level rise of 0.5 meters by 2100. Attribute_Definition_Source: USGS Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: -9999 Enumerated_Domain_Value_Definition: No Data Enumerated_Domain_Value_Definition_Source: USGS Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: 10000 Enumerated_Domain_Value_Definition: Value larger than or equal to 10000 Enumerated_Domain_Value_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: -927 Range_Domain_Maximum: 10000 Attribute_Units_of_Measure: year Attribute: Attribute_Label: GMSL10 Attribute_Definition: Lifespan for a marsh unit (in years) for global mean sea level rise of 1.0 meters by 2100. Attribute_Definition_Source: USGS Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: -9999 Enumerated_Domain_Value_Definition: No Data Enumerated_Domain_Value_Definition_Source: USGS Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: 10000 Enumerated_Domain_Value_Definition: Value larger than or equal to 10000 Enumerated_Domain_Value_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: -244 Range_Domain_Maximum: 10000 Attribute_Units_of_Measure: year Attribute: Attribute_Label: FLG Attribute_Definition: Marsh unit flag indicating anomalous marsh units based on absence of vegetation, elevation and surface area. 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; (-1000) marsh unit surface area less than 900 square meters; and (0) no flag. Combination of negative values indicate 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: -1101 Range_Domain_Maximum: 0 Attribute_Units_of_Measure: None Overview_Description: Entity_and_Attribute_Overview: In this dataset, lifespan estimates for each conceptual salt marsh unit in the Assateague Island and Chincoteague Bay salt marsh complex has been calculated based on the 1-meter resolution raster 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 values and elevation is assumed to be 1 meter and 0.01, 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_lifespan_ASISp 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. Not for navigational use. Standard_Order_Process: Digital_Form: Digital_Transfer_Information: Format_Name: shapefile Format_Version_Number: ArcGIS Pro 2.8.2 Format_Information_Content: This zipped file contains a polygon shapefile and its components, a style layer descriptor file, metadata in xml, txt and html formats and a browse image. Digital_Transfer_Option: Online_Option: Computer_Contact_Information: Network_Address: Network_Resource_Name: https://www.sciencebase.gov/catalog/file/get/6267eb10d34e76103ccf4d98 Network_Resource_Name: https://doi.org/10.5066/P9WSYCAN 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. 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/6267eb10d34e76103ccf4d98?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/6267eb10d34e76103ccf4d98?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 data set. Metadata_Reference_Information: Metadata_Date: 20220526 Metadata_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey Contact_Person: Zafer Defne Contact_Position: Oceanographer Contact_Address: Address_Type: mailing and physical address Address: 384 Woods Hole Road City: Woods Hole State_or_Province: MA Postal_Code: 02543 Contact_Voice_Telephone: 508-548-8700 x2254 Contact_Facsimile_Telephone: 508-457-2310 Contact_Electronic_Mail_Address: zdefne@usgs.gov Metadata_Standard_Name: FGDC Content Standard for Digital Geospatial Metadata Metadata_Standard_Version: FGDC-STD-001-1998