gov.noaa.nodc:0276236 eng utf8 dataset NOAA National Centers for Environmental Information ncei.info@noaa.gov https://www.ncei.noaa.gov/contact HTTPS NOAA Contact Information Information for contacts at NCEI. information custodian 2025-05-16T15:50:36Z ISO 19115-2 Geographic Information - Metadata - Part 2: Extensions for Imagery and Gridded Data ISO 19115-2:2009(E) Salt Marsh Retreat Rates and Hydrodynamic Data for the Great Marsh in Massachusetts, which comprises Plum Island Sound and Essex Bay, from 08-25-2015 to 06-24-2022 (NCEI Accession 0276236) 2023-01-23 publication 2023-01-05 creation NOAA National Centers for Environmental Information gov.noaa.nodc:0276236 NCEI Archive Management System 0276236 NOAA National Centers for Environmental Information ncei.info@noaa.gov https://www.ncei.noaa.gov/contact HTTPS NCEI Contact Information Information for contacts at NCEI. information publisher Lucila Houttuijn Bloemendaal Boston University (BU) luci.jolie@gmail.com) http://www.bu.edu HTTP Boston University (BU) website Institution web page information resourceProvider Boston University (BU) http://www.bu.edu HTTP Boston University (BU) website Institution web page information resourceProvider Lucila Houttuijn Bloemendaal Boston University (BU) luci.jolie@gmail.com http://www.bu.edu HTTP Boston University (BU) website Institution web page information pointOfContact FitzGerald, Duncan Boston University dunc@bu.edu http://www.bu.edu HTTP Boston University (BU) website Institution web page information author Hughes, Zoe Boston University zoeh@bu.edu http://www.bu.edu HTTP Boston University (BU) website Institution web page information author Novak, Alyssa Boston University abnovak@bu.edu http://www.bu.edu HTTP Boston University (BU) website Institution web page information author Georgiou, Ioannis Boston University http://www.bu.edu HTTP Boston University (BU) website Institution web page information author Boston University (BU) http://www.bu.edu HTTP Boston University (BU) website Institution web page information contributor tableDigital The dataset provides measured salt marsh shoreline retreat rates and estimated hydrodynamic data for twelve sites in the Great Marsh system in Massachusetts, which comprises Plum Island Sound and Essex Bay. Shoreline retreat rates were measured using repeat RTK-GPS shoreline surveys from 2015 to 2020 and Digital Shoreline Analysis System (DSAS). Estimated hydrodynamic data for the twelve sites were derived from 64 Simulating Nearshore Waves (SWAN) simulations and a calibrated Delft3D hydrodynamic model. The data were generated for a study examining the relationship between wave power and salt marsh retreat. These data were collected to support the study of marsh edge erosion in the Great Marsh in Massachusetts and its relationship to hydrodynamics and other processes. Funding Agency: National Science Foundation; Directorate for Geosciences completed historicalArchive NOAA National Centers for Environmental Information ncei.info@noaa.gov https://www.ncei.noaa.gov/contact HTTPS NCEI Contact Information Information for contacts at NCEI. information pointOfContact asNeeded https://www.ncei.noaa.gov/access/metadata/landing-page/bin/gfx?id=gov.noaa.nodc:0276236 Preview graphic PNG 0276236 NCEI ACCESSION NUMBER 2022-12-16 publication CURRENT SPEED LATITUDE LONGITUDE SHORELINE WAVE DATA WAVE ENERGY WIND DIRECTION theme NODC DATA TYPES THESAURUS GPS satellite sensor - general instrument NODC INSTRUMENT TYPES THESAURUS in situ model output satellite data theme NODC OBSERVATION TYPES THESAURUS Boston University dataCentre NODC COLLECTING INSTITUTION NAMES THESAURUS Boston University dataCentre NODC SUBMITTING INSTITUTION NAMES THESAURUS North Atlantic Ocean place NODC SEA AREA NAMES THESAURUS oceanography theme WMO_CategoryCode 2012-09-15 publication EARTH SCIENCE > ATMOSPHERE > ATMOSPHERIC WINDS > SURFACE WINDS > WIND DIRECTION EARTH SCIENCE > OCEANS > COASTAL PROCESSES > SHORELINES EARTH SCIENCE > OCEANS > OCEAN CIRCULATION > OCEAN CURRENTS EARTH SCIENCE > OCEANS > OCEAN WAVES theme Global Change Master Directory (GCMD) Science Keywords 2026 revision 24 Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA) Greenbelt MD https://forum.earthdata.nasa.gov/app.php/tag/GCMD%2BKeywords HTTPS GCMD Keyword Forum Page Global Change Master Directory (GCMD). 2025. GCMD Keywords, Version 21. Greenbelt, MD: Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA). URL (GCMD Keyword Forum Page): https://forum.earthdata.nasa.gov/app.php/tag/GCMD+Keywords information custodian Channel Curvature Date of Shoreline Survey 1 Date of Shoreline Survey 2 Date of Shoreline Survey 3 Date of Shoreline Survey 4 Ebb Current Velocity Flood Current Velocity Length of Shoreline Surveyed Number of Transects Used Retreat Rate Retreat Rate Uncertainty Site Wave Energy Wave Power (All Wind Directions): Wave Power (E Wind Direction) Wave Power (ENE Wind Direction) Wave Power (ESE Wind Direction) Wave Power (N Wind Direction) Wave Power (NE Wind Direction) Wave Power (NNE Wind Direction): Wave Power (NNW Wind Direction) Wave Power (NW Wind Direction) Wave Power (S Wind Direction) Wave Power (SE Wind Direction) Wave Power (SSE Wind Direction) Wave Power (SSW Wind Direction) Wave Power (SW Wind Direction) Wave Power (W Wind Direction) Wave Power (WNW Wind Direction) Wave Power (WSW Wind Direction) theme Provider Keywords GPS RECEIVERS > GPS RECEIVERS instrument Global Change Master Directory (GCMD) Instrument Keywords 2026 revision 24 Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA) Greenbelt MD https://forum.earthdata.nasa.gov/app.php/tag/GCMD%2BKeywords HTTPS GCMD Keyword Forum Page Global Change Master Directory (GCMD). 2025. GCMD Keywords, Version 21. Greenbelt, MD: Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA). URL (GCMD Keyword Forum Page): https://forum.earthdata.nasa.gov/app.php/tag/GCMD+Keywords information custodian Delft3D Digital Shoreline Analysis System (DSAS) RTK-GPS Satellite Imagery Simulating Waves Nearshore (SWAN) instrument Provider Instruments OCEAN > ATLANTIC OCEAN > NORTH ATLANTIC OCEAN place Global Change Master Directory (GCMD) Location Keywords 2026 revision 24 Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA) Greenbelt MD https://forum.earthdata.nasa.gov/app.php/tag/GCMD%2BKeywords HTTPS GCMD Keyword Forum Page Global Change Master Directory (GCMD). 2025. GCMD Keywords, Version 21. Greenbelt, MD: Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA). URL (GCMD Keyword Forum Page): https://forum.earthdata.nasa.gov/app.php/tag/GCMD+Keywords information custodian Essex Bay Plum Island Sound place Provider Place Names LW4PP4 Send2NCEI Submission Package ID accessLevel: public otherRestrictions Cite as: FitzGerald, Duncan; Hughes, Zoe; Novak, Alyssa; Georgiou, Ioannis (2023). Salt Marsh Retreat Rates and Hydrodynamic Data for the Great Marsh in Massachusetts, which comprises Plum Island Sound and Essex Bay, from 08-25-2015 to 06-24-2022 (NCEI Accession 0276236). [indicate subset used]. NOAA National Centers for Environmental Information. Dataset. https://www.ncei.noaa.gov/archive/accession/0276236. Accessed [date]. 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The user is responsible for the results of any application of this data for other than its intended purpose. eng; USA utf8 environment oceans climatologyMeteorologyAtmosphere -71 -70.5 42.6 42.9 2015-08-25 2022-06-24 NOAA National Centers for Environmental Information +1-301-713-3277 ncei.info@noaa.gov pointOfContact In most cases, electronic downloads of the data are free. However, fees may apply for custom orders, data certifications, copies of analog materials, and data distribution on physical media. Contact NCEI for other distribution options and instructions. CSV 0.276 https://www.ncei.noaa.gov/archive/accession/0276236 HTTPS Web browser NCEI Dataset Landing Page Navigate directly to the URL for a descriptive web page with download links. information https://www.ncei.noaa.gov/archive/accession/oas/276236 HTTPS Web browser Descriptive Information Navigate directly to the URL for a descriptive web page with download links. information https://www.ncei.noaa.gov/archive/accession/download/276236 HTTPS Web browser HTTPS Navigate directly to the URL for data access and direct download. download ftp://ftp-oceans.ncei.noaa.gov/nodc/archive/arc0210/0276236/ FTP Any FTP client FTP These data are available through the File Transfer Protocol (FTP). FTP is no longer supported by most internet browsers. You may copy and paste the FTP link to the data into an FTP client (e.g., FileZilla or WinSCP). download dataset NCEI Accession 0276236 v1.1 was published. 2023-01-23T18:44:36Z NCEI Accession 0276236 v1.1 publication https://www.ncei.noaa.gov/archive/accession/0276236/1.1 HTTPS NCEI Accession 0276236 v1.1 published 2023-01-23T18:44:36Z download dataset Parameter or Variable: Retreat Rate (measured); Units: meters per year; Observation Category: in situ; Sampling Instrument: RTK-GPS; Sampling and Analyzing Method: At each site, the marsh edge was surveyed using the RTK-GPS covering approximately 70 meters of shoreline. Each site was surveyed at least three times, in the summer of 2015, in 2016, and either 2019 or 2020. The RTK-GPS points were processed and corrected using the NOAA Online Positioning User Service (OPUS), and retreat rates were calculated using the linear regression rate from the Digital Shoreline Analysis System (DSAS), a software add-in for Esri ArcGIS desktop which calculates rate-of-change statistics from multiple historic shoreline positions. Retreat rate uncertainty values were calculated using DSAS using the built-in uncertainty calculator. Parameter or Variable: Retreat Rate Uncertainty (calculated); Units: meters per year; Observation Category: other; Sampling Instrument: Digital Shoreline Analysis System (DSAS); Sampling and Analyzing Method: Retreat rate uncertainty values were calculated using DSAS using the built-in uncertainty calculator. Parameter or Variable: Wave Power (All Wind Directions): (calculated); Units: Watts per meter; Observation Category: model output; Sampling Instrument: Simulating Waves Nearshore (SWAN); Sampling and Analyzing Method: Estimated wave power, represented as a frequency-weighted mean over a stationary SWAN (Simulating Waves Nearshore) run, over 16 wind directions (N, NNE, NE, ENE, E, ESE, SE, SSE, S, SSW, SW, WSW, W, WNW, NW, NNW). Units are watts per meter (W/m). Significant wave heights impacting the Great Marsh study sites were estimated using Simulating Waves Nearshore (SWAN). SWAN is a numerical wave model that provides estimates of wave parameters in coastal and estuarine areas from given bottom and wind conditions. For this study’s model, wind conditions were derived from the NOAA data buoy station IOSN3 in Isle of Shoals, New Hampshire, based on the 1996-2020 data record. A 20 m x 20 m bathymetric grid for the study region was created by combining NOAA hydrographic survey data (from NOAA NCEI Bathymetric Data Viewer), 2013-2014 USGS lidar data, and extensive single-beam sonar data collected in the field. To ensure all the sites of interest were exposed to waves in the simulation, the datum of the bathymetric grid was set to MHHW, or 1.47 m above MSL in this region. SWAN was run in stationary mode for 16 different wind directions and for 4 different wind speed bins: 5-10 m/s, 10-15 m/s, 15-20 m/s, and winds faster than 20 m/s, resulting in 64 simulations. Wave energy (in J/m2) was calculated from the significant wave heights computed by SWAN using the following formula, E=1/8 ρgH_sig^2, where E is wave energy, ρ is the density of water, g is the acceleration due to gravity, and H_sig is the significant wave height. Wave power (in W/m), also called wave energy flux or wave power density, was calculated using the following formula, P_w= Ec_g, where P_w is the wave power or energy flux, and c_g is the group velocity, calculated through the expression c_g= c/2 [1+ 2kD/(sinh⁡(2kD))], where c is the celerity, k is the angular wave number, and D is the water depth. Weighted means of wave height, energy, and power were calculated at each site using the frequency of wind speed and direction conditions determined using NOAA buoy data. Parameter or Variable: Wave Power (N Wind Direction) (calculated); Units: Watts per meter; Observation Category: model output; Sampling Instrument: Simulating Waves Nearshore (SWAN); Sampling and Analyzing Method: Estimated wave power from waves generated by winds coming from the North (N) direction. Units are watts per meter (W/m). Significant wave heights impacting the Great Marsh study sites were estimated using Simulating Waves Nearshore (SWAN). SWAN is a numerical wave model that provides estimates of wave parameters in coastal and estuarine areas from given bottom and wind conditions. For this study’s model, wind conditions were derived from the NOAA data buoy station IOSN3 in Isle of Shoals, New Hampshire, based on the 1996-2020 data record. A 20 m x 20 m bathymetric grid for the study region was created by combining NOAA hydrographic survey data (from NOAA NCEI Bathymetric Data Viewer), 2013-2014 USGS lidar data, and extensive single-beam sonar data collected in the field. To ensure all the sites of interest were exposed to waves in the simulation, the datum of the bathymetric grid was set to MHHW, or 1.47 m above MSL in this region. SWAN was run in stationary mode for 16 different wind directions and for 4 different wind speed bins: 5-10 m/s, 10-15 m/s, 15-20 m/s, and winds faster than 20 m/s, resulting in 64 simulations. Wave energy (in J/m2) was calculated from the significant wave heights computed by SWAN using the following formula, E=1/8 ρgH_sig^2, where E is wave energy, ρ is the density of water, g is the acceleration due to gravity, and H_sig is the significant wave height. Wave power (in W/m), also called wave energy flux or wave power density, was calculated using the following formula, P_w= Ec_g, where P_w is the wave power or energy flux, and c_g is the group velocity, calculated through the expression c_g= c/2 [1+ 2kD/(sinh⁡(2kD))], where c is the celerity, k is the angular wave number, and D is the water depth. Weighted means of wave height, energy, and power were calculated at each site using the frequency of wind speed and direction conditions determined using NOAA buoy data. Parameter or Variable: Wave Power (NNE Wind Direction): (calculated); Units: Watts per meter; Observation Category: model output; Sampling Instrument: Simulating Waves Nearshore (SWAN); Sampling and Analyzing Method: Estimated wave power from waves generated by winds coming from the North-Northeast (NNE) direction. Units are watts per meter (W/m). Significant wave heights impacting the Great Marsh study sites were estimated using Simulating Waves Nearshore (SWAN). SWAN is a numerical wave model that provides estimates of wave parameters in coastal and estuarine areas from given bottom and wind conditions. For this study’s model, wind conditions were derived from the NOAA data buoy station IOSN3 in Isle of Shoals, New Hampshire, based on the 1996-2020 data record. A 20 m x 20 m bathymetric grid for the study region was created by combining NOAA hydrographic survey data (from NOAA NCEI Bathymetric Data Viewer), 2013-2014 USGS lidar data, and extensive single-beam sonar data collected in the field. To ensure all the sites of interest were exposed to waves in the simulation, the datum of the bathymetric grid was set to MHHW, or 1.47 m above MSL in this region. SWAN was run in stationary mode for 16 different wind directions and for 4 different wind speed bins: 5-10 m/s, 10-15 m/s, 15-20 m/s, and winds faster than 20 m/s, resulting in 64 simulations. Wave energy (in J/m2) was calculated from the significant wave heights computed by SWAN using the following formula, E=1/8 ρgH_sig^2, where E is wave energy, ρ is the density of water, g is the acceleration due to gravity, and H_sig is the significant wave height. Wave power (in W/m), also called wave energy flux or wave power density, was calculated using the following formula, P_w= Ec_g, where P_w is the wave power or energy flux, and c_g is the group velocity, calculated through the expression c_g= c/2 [1+ 2kD/(sinh⁡(2kD))], where c is the celerity, k is the angular wave number, and D is the water depth. Weighted means of wave height, energy, and power were calculated at each site using the frequency of wind speed and direction conditions determined using NOAA buoy data. Parameter or Variable: Wave Power (NE Wind Direction) (calculated); Units: Watts per meter; Observation Category: model output; Sampling Instrument: Simulating Waves Nearshore (SWAN); Sampling and Analyzing Method: Estimated wave power from waves generated by winds coming from the Northeast (NE) direction. Units are watts per meter (W/m). Significant wave heights impacting the Great Marsh study sites were estimated using Simulating Waves Nearshore (SWAN). SWAN is a numerical wave model that provides estimates of wave parameters in coastal and estuarine areas from given bottom and wind conditions. For this study’s model, wind conditions were derived from the NOAA data buoy station IOSN3 in Isle of Shoals, New Hampshire, based on the 1996-2020 data record. A 20 m x 20 m bathymetric grid for the study region was created by combining NOAA hydrographic survey data (from NOAA NCEI Bathymetric Data Viewer), 2013-2014 USGS lidar data, and extensive single-beam sonar data collected in the field. To ensure all the sites of interest were exposed to waves in the simulation, the datum of the bathymetric grid was set to MHHW, or 1.47 m above MSL in this region. SWAN was run in stationary mode for 16 different wind directions and for 4 different wind speed bins: 5-10 m/s, 10-15 m/s, 15-20 m/s, and winds faster than 20 m/s, resulting in 64 simulations. Wave energy (in J/m2) was calculated from the significant wave heights computed by SWAN using the following formula, E=1/8 ρgH_sig^2, where E is wave energy, ρ is the density of water, g is the acceleration due to gravity, and H_sig is the significant wave height. Wave power (in W/m), also called wave energy flux or wave power density, was calculated using the following formula, P_w= Ec_g, where P_w is the wave power or energy flux, and c_g is the group velocity, calculated through the expression c_g= c/2 [1+ 2kD/(sinh⁡(2kD))], where c is the celerity, k is the angular wave number, and D is the water depth. Weighted means of wave height, energy, and power were calculated at each site using the frequency of wind speed and direction conditions determined using NOAA buoy data. Parameter or Variable: Wave Power (ENE Wind Direction) (calculated); Units: Watts per meter; Observation Category: model output; Sampling Instrument: Simulating Waves Nearshore (SWAN); Sampling and Analyzing Method: Estimated wave power from waves generated by winds coming from the East-Northeast (ENE) direction. Units are watts per meter (W/m). Significant wave heights impacting the Great Marsh study sites were estimated using Simulating Waves Nearshore (SWAN). SWAN is a numerical wave model that provides estimates of wave parameters in coastal and estuarine areas from given bottom and wind conditions. For this study’s model, wind conditions were derived from the NOAA data buoy station IOSN3 in Isle of Shoals, New Hampshire, based on the 1996-2020 data record. A 20 m x 20 m bathymetric grid for the study region was created by combining NOAA hydrographic survey data (from NOAA NCEI Bathymetric Data Viewer), 2013-2014 USGS lidar data, and extensive single-beam sonar data collected in the field. To ensure all the sites of interest were exposed to waves in the simulation, the datum of the bathymetric grid was set to MHHW, or 1.47 m above MSL in this region. SWAN was run in stationary mode for 16 different wind directions and for 4 different wind speed bins: 5-10 m/s, 10-15 m/s, 15-20 m/s, and winds faster than 20 m/s, resulting in 64 simulations. Wave energy (in J/m2) was calculated from the significant wave heights computed by SWAN using the following formula, E=1/8 ρgH_sig^2, where E is wave energy, ρ is the density of water, g is the acceleration due to gravity, and H_sig is the significant wave height. Wave power (in W/m), also called wave energy flux or wave power density, was calculated using the following formula, P_w= Ec_g, where P_w is the wave power or energy flux, and c_g is the group velocity, calculated through the expression c_g= c/2 [1+ 2kD/(sinh⁡(2kD))], where c is the celerity, k is the angular wave number, and D is the water depth. Weighted means of wave height, energy, and power were calculated at each site using the frequency of wind speed and direction conditions determined using NOAA buoy data. Parameter or Variable: Wave Power (E Wind Direction) (calculated); Units: attowatt; Observation Category: model output; Sampling Instrument: Simulating Waves Nearshore (SWAN); Sampling and Analyzing Method: Estimated wave power from waves generated by winds coming from the East (E) direction. Units are watts per meter (W/m). Significant wave heights impacting the Great Marsh study sites were estimated using Simulating Waves Nearshore (SWAN). SWAN is a numerical wave model that provides estimates of wave parameters in coastal and estuarine areas from given bottom and wind conditions. For this study’s model, wind conditions were derived from the NOAA data buoy station IOSN3 in Isle of Shoals, New Hampshire, based on the 1996-2020 data record. A 20 m x 20 m bathymetric grid for the study region was created by combining NOAA hydrographic survey data (from NOAA NCEI Bathymetric Data Viewer), 2013-2014 USGS lidar data, and extensive single-beam sonar data collected in the field. To ensure all the sites of interest were exposed to waves in the simulation, the datum of the bathymetric grid was set to MHHW, or 1.47 m above MSL in this region. SWAN was run in stationary mode for 16 different wind directions and for 4 different wind speed bins: 5-10 m/s, 10-15 m/s, 15-20 m/s, and winds faster than 20 m/s, resulting in 64 simulations. Wave energy (in J/m2) was calculated from the significant wave heights computed by SWAN using the following formula, E=1/8 ρgH_sig^2, where E is wave energy, ρ is the density of water, g is the acceleration due to gravity, and H_sig is the significant wave height. Wave power (in W/m), also called wave energy flux or wave power density, was calculated using the following formula, P_w= Ec_g, where P_w is the wave power or energy flux, and c_g is the group velocity, calculated through the expression c_g= c/2 [1+ 2kD/(sinh⁡(2kD))], where c is the celerity, k is the angular wave number, and D is the water depth. Weighted means of wave height, energy, and power were calculated at each site using the frequency of wind speed and direction conditions determined using NOAA buoy data. Parameter or Variable: Wave Power (ESE Wind Direction) (calculated); Units: Watts per meter; Observation Category: model output; Sampling Instrument: Simulating Waves Nearshore (SWAN); Sampling and Analyzing Method: Estimated wave power from waves generated by winds coming from the East-Southeast (ESE) direction. Units are watts per meter (W/m). Significant wave heights impacting the Great Marsh study sites were estimated using Simulating Waves Nearshore (SWAN). SWAN is a numerical wave model that provides estimates of wave parameters in coastal and estuarine areas from given bottom and wind conditions. For this study’s model, wind conditions were derived from the NOAA data buoy station IOSN3 in Isle of Shoals, New Hampshire, based on the 1996-2020 data record. A 20 m x 20 m bathymetric grid for the study region was created by combining NOAA hydrographic survey data (from NOAA NCEI Bathymetric Data Viewer), 2013-2014 USGS lidar data, and extensive single-beam sonar data collected in the field. To ensure all the sites of interest were exposed to waves in the simulation, the datum of the bathymetric grid was set to MHHW, or 1.47 m above MSL in this region. SWAN was run in stationary mode for 16 different wind directions and for 4 different wind speed bins: 5-10 m/s, 10-15 m/s, 15-20 m/s, and winds faster than 20 m/s, resulting in 64 simulations. Wave energy (in J/m2) was calculated from the significant wave heights computed by SWAN using the following formula, E=1/8 ρgH_sig^2, where E is wave energy, ρ is the density of water, g is the acceleration due to gravity, and H_sig is the significant wave height. Wave power (in W/m), also called wave energy flux or wave power density, was calculated using the following formula, P_w= Ec_g, where P_w is the wave power or energy flux, and c_g is the group velocity, calculated through the expression c_g= c/2 [1+ 2kD/(sinh⁡(2kD))], where c is the celerity, k is the angular wave number, and D is the water depth. Weighted means of wave height, energy, and power were calculated at each site using the frequency of wind speed and direction conditions determined using NOAA buoy data. Parameter or Variable: Wave Power (SE Wind Direction) (calculated); Units: Watts per meter; Observation Category: model output; Sampling Instrument: Simulating Waves Nearshore (SWAN); Sampling and Analyzing Method: Estimated wave power from waves generated by winds coming from the Southeast (SE) direction. Units are watts per meter (W/m). Significant wave heights impacting the Great Marsh study sites were estimated using Simulating Waves Nearshore (SWAN). SWAN is a numerical wave model that provides estimates of wave parameters in coastal and estuarine areas from given bottom and wind conditions. For this study’s model, wind conditions were derived from the NOAA data buoy station IOSN3 in Isle of Shoals, New Hampshire, based on the 1996-2020 data record. A 20 m x 20 m bathymetric grid for the study region was created by combining NOAA hydrographic survey data (from NOAA NCEI Bathymetric Data Viewer), 2013-2014 USGS lidar data, and extensive single-beam sonar data collected in the field. To ensure all the sites of interest were exposed to waves in the simulation, the datum of the bathymetric grid was set to MHHW, or 1.47 m above MSL in this region. SWAN was run in stationary mode for 16 different wind directions and for 4 different wind speed bins: 5-10 m/s, 10-15 m/s, 15-20 m/s, and winds faster than 20 m/s, resulting in 64 simulations. Wave energy (in J/m2) was calculated from the significant wave heights computed by SWAN using the following formula, E=1/8 ρgH_sig^2, where E is wave energy, ρ is the density of water, g is the acceleration due to gravity, and H_sig is the significant wave height. Wave power (in W/m), also called wave energy flux or wave power density, was calculated using the following formula, P_w= Ec_g, where P_w is the wave power or energy flux, and c_g is the group velocity, calculated through the expression c_g= c/2 [1+ 2kD/(sinh⁡(2kD))], where c is the celerity, k is the angular wave number, and D is the water depth. Weighted means of wave height, energy, and power were calculated at each site using the frequency of wind speed and direction conditions determined using NOAA buoy data. Parameter or Variable: Wave Power (SSE Wind Direction) (calculated); Units: Watts per meter; Observation Category: model output; Sampling Instrument: Simulating Waves Nearshore (SWAN); Sampling and Analyzing Method: Estimated wave power from waves generated by winds coming from the South-Southeast (SSE) direction. Units are watts per meter (W/m). Significant wave heights impacting the Great Marsh study sites were estimated using Simulating Waves Nearshore (SWAN). SWAN is a numerical wave model that provides estimates of wave parameters in coastal and estuarine areas from given bottom and wind conditions. For this study’s model, wind conditions were derived from the NOAA data buoy station IOSN3 in Isle of Shoals, New Hampshire, based on the 1996-2020 data record. A 20 m x 20 m bathymetric grid for the study region was created by combining NOAA hydrographic survey data (from NOAA NCEI Bathymetric Data Viewer), 2013-2014 USGS lidar data, and extensive single-beam sonar data collected in the field. To ensure all the sites of interest were exposed to waves in the simulation, the datum of the bathymetric grid was set to MHHW, or 1.47 m above MSL in this region. SWAN was run in stationary mode for 16 different wind directions and for 4 different wind speed bins: 5-10 m/s, 10-15 m/s, 15-20 m/s, and winds faster than 20 m/s, resulting in 64 simulations. Wave energy (in J/m2) was calculated from the significant wave heights computed by SWAN using the following formula, E=1/8 ρgH_sig^2, where E is wave energy, ρ is the density of water, g is the acceleration due to gravity, and H_sig is the significant wave height. Wave power (in W/m), also called wave energy flux or wave power density, was calculated using the following formula, P_w= Ec_g, where P_w is the wave power or energy flux, and c_g is the group velocity, calculated through the expression c_g= c/2 [1+ 2kD/(sinh⁡(2kD))], where c is the celerity, k is the angular wave number, and D is the water depth. Weighted means of wave height, energy, and power were calculated at each site using the frequency of wind speed and direction conditions determined using NOAA buoy data. Parameter or Variable: Wave Power (S Wind Direction) (calculated); Units: Watts per meter; Observation Category: model output; Sampling Instrument: Simulating Waves Nearshore (SWAN); Sampling and Analyzing Method: Estimated wave power from waves generated by winds coming from the South (S) direction. Units are watts per meter (W/m). Significant wave heights impacting the Great Marsh study sites were estimated using Simulating Waves Nearshore (SWAN). SWAN is a numerical wave model that provides estimates of wave parameters in coastal and estuarine areas from given bottom and wind conditions. For this study’s model, wind conditions were derived from the NOAA data buoy station IOSN3 in Isle of Shoals, New Hampshire, based on the 1996-2020 data record. A 20 m x 20 m bathymetric grid for the study region was created by combining NOAA hydrographic survey data (from NOAA NCEI Bathymetric Data Viewer), 2013-2014 USGS lidar data, and extensive single-beam sonar data collected in the field. To ensure all the sites of interest were exposed to waves in the simulation, the datum of the bathymetric grid was set to MHHW, or 1.47 m above MSL in this region. SWAN was run in stationary mode for 16 different wind directions and for 4 different wind speed bins: 5-10 m/s, 10-15 m/s, 15-20 m/s, and winds faster than 20 m/s, resulting in 64 simulations. Wave energy (in J/m2) was calculated from the significant wave heights computed by SWAN using the following formula, E=1/8 ρgH_sig^2, where E is wave energy, ρ is the density of water, g is the acceleration due to gravity, and H_sig is the significant wave height. Wave power (in W/m), also called wave energy flux or wave power density, was calculated using the following formula, P_w= Ec_g, where P_w is the wave power or energy flux, and c_g is the group velocity, calculated through the expression c_g= c/2 [1+ 2kD/(sinh⁡(2kD))], where c is the celerity, k is the angular wave number, and D is the water depth. Weighted means of wave height, energy, and power were calculated at each site using the frequency of wind speed and direction conditions determined using NOAA buoy data. Parameter or Variable: Wave Power (SSW Wind Direction) (calculated); Units: Watts per meter; Observation Category: model output; Sampling Instrument: Simulating Waves Nearshore (SWAN); Sampling and Analyzing Method: Estimated wave power from waves generated by winds coming from the South-Southwest (SSW) direction. Units are watts per meter (W/m). Significant wave heights impacting the Great Marsh study sites were estimated using Simulating Waves Nearshore (SWAN). SWAN is a numerical wave model that provides estimates of wave parameters in coastal and estuarine areas from given bottom and wind conditions. For this study’s model, wind conditions were derived from the NOAA data buoy station IOSN3 in Isle of Shoals, New Hampshire, based on the 1996-2020 data record. A 20 m x 20 m bathymetric grid for the study region was created by combining NOAA hydrographic survey data (from NOAA NCEI Bathymetric Data Viewer), 2013-2014 USGS lidar data, and extensive single-beam sonar data collected in the field. To ensure all the sites of interest were exposed to waves in the simulation, the datum of the bathymetric grid was set to MHHW, or 1.47 m above MSL in this region. SWAN was run in stationary mode for 16 different wind directions and for 4 different wind speed bins: 5-10 m/s, 10-15 m/s, 15-20 m/s, and winds faster than 20 m/s, resulting in 64 simulations. Wave energy (in J/m2) was calculated from the significant wave heights computed by SWAN using the following formula, E=1/8 ρgH_sig^2, where E is wave energy, ρ is the density of water, g is the acceleration due to gravity, and H_sig is the significant wave height. Wave power (in W/m), also called wave energy flux or wave power density, was calculated using the following formula, P_w= Ec_g, where P_w is the wave power or energy flux, and c_g is the group velocity, calculated through the expression c_g= c/2 [1+ 2kD/(sinh⁡(2kD))], where c is the celerity, k is the angular wave number, and D is the water depth. Weighted means of wave height, energy, and power were calculated at each site using the frequency of wind speed and direction conditions determined using NOAA buoy data. Parameter or Variable: Wave Power (SW Wind Direction) (calculated); Units: Watts per meter; Observation Category: model output; Sampling Instrument: Simulating Waves Nearshore (SWAN); Sampling and Analyzing Method: Estimated wave power from waves generated by winds coming from the Southwest (SW) direction. Units are watts per meter (W/m). Significant wave heights impacting the Great Marsh study sites were estimated using Simulating Waves Nearshore (SWAN). SWAN is a numerical wave model that provides estimates of wave parameters in coastal and estuarine areas from given bottom and wind conditions. For this study’s model, wind conditions were derived from the NOAA data buoy station IOSN3 in Isle of Shoals, New Hampshire, based on the 1996-2020 data record. A 20 m x 20 m bathymetric grid for the study region was created by combining NOAA hydrographic survey data (from NOAA NCEI Bathymetric Data Viewer), 2013-2014 USGS lidar data, and extensive single-beam sonar data collected in the field. To ensure all the sites of interest were exposed to waves in the simulation, the datum of the bathymetric grid was set to MHHW, or 1.47 m above MSL in this region. SWAN was run in stationary mode for 16 different wind directions and for 4 different wind speed bins: 5-10 m/s, 10-15 m/s, 15-20 m/s, and winds faster than 20 m/s, resulting in 64 simulations. Wave energy (in J/m2) was calculated from the significant wave heights computed by SWAN using the following formula, E=1/8 ρgH_sig^2, where E is wave energy, ρ is the density of water, g is the acceleration due to gravity, and H_sig is the significant wave height. Wave power (in W/m), also called wave energy flux or wave power density, was calculated using the following formula, P_w= Ec_g, where P_w is the wave power or energy flux, and c_g is the group velocity, calculated through the expression c_g= c/2 [1+ 2kD/(sinh⁡(2kD))], where c is the celerity, k is the angular wave number, and D is the water depth. Weighted means of wave height, energy, and power were calculated at each site using the frequency of wind speed and direction conditions determined using NOAA buoy data. Parameter or Variable: Wave Power (WSW Wind Direction) (calculated); Units: Watts per meter; Observation Category: model output; Sampling Instrument: Simulating Waves Nearshore (SWAN); Sampling and Analyzing Method: Estimated wave power from waves generated by winds coming from the West-Southwest (WSW) direction. Units are watts per meter (W/m). Significant wave heights impacting the Great Marsh study sites were estimated using Simulating Waves Nearshore (SWAN). SWAN is a numerical wave model that provides estimates of wave parameters in coastal and estuarine areas from given bottom and wind conditions. For this study’s model, wind conditions were derived from the NOAA data buoy station IOSN3 in Isle of Shoals, New Hampshire, based on the 1996-2020 data record. A 20 m x 20 m bathymetric grid for the study region was created by combining NOAA hydrographic survey data (from NOAA NCEI Bathymetric Data Viewer), 2013-2014 USGS lidar data, and extensive single-beam sonar data collected in the field. To ensure all the sites of interest were exposed to waves in the simulation, the datum of the bathymetric grid was set to MHHW, or 1.47 m above MSL in this region. SWAN was run in stationary mode for 16 different wind directions and for 4 different wind speed bins: 5-10 m/s, 10-15 m/s, 15-20 m/s, and winds faster than 20 m/s, resulting in 64 simulations. Wave energy (in J/m2) was calculated from the significant wave heights computed by SWAN using the following formula, E=1/8 ρgH_sig^2, where E is wave energy, ρ is the density of water, g is the acceleration due to gravity, and H_sig is the significant wave height. Wave power (in W/m), also called wave energy flux or wave power density, was calculated using the following formula, P_w= Ec_g, where P_w is the wave power or energy flux, and c_g is the group velocity, calculated through the expression c_g= c/2 [1+ 2kD/(sinh⁡(2kD))], where c is the celerity, k is the angular wave number, and D is the water depth. Weighted means of wave height, energy, and power were calculated at each site using the frequency of wind speed and direction conditions determined using NOAA buoy data. Parameter or Variable: Wave Power (W Wind Direction) (calculated); Units: Watts per meter; Observation Category: model output; Sampling Instrument: Simulating Waves Nearshore (SWAN); Sampling and Analyzing Method: Estimated wave power from waves generated by winds coming from the West (W) direction. Units are watts per meter (W/m). Significant wave heights impacting the Great Marsh study sites were estimated using Simulating Waves Nearshore (SWAN). SWAN is a numerical wave model that provides estimates of wave parameters in coastal and estuarine areas from given bottom and wind conditions. For this study’s model, wind conditions were derived from the NOAA data buoy station IOSN3 in Isle of Shoals, New Hampshire, based on the 1996-2020 data record. A 20 m x 20 m bathymetric grid for the study region was created by combining NOAA hydrographic survey data (from NOAA NCEI Bathymetric Data Viewer), 2013-2014 USGS lidar data, and extensive single-beam sonar data collected in the field. To ensure all the sites of interest were exposed to waves in the simulation, the datum of the bathymetric grid was set to MHHW, or 1.47 m above MSL in this region. SWAN was run in stationary mode for 16 different wind directions and for 4 different wind speed bins: 5-10 m/s, 10-15 m/s, 15-20 m/s, and winds faster than 20 m/s, resulting in 64 simulations. Wave energy (in J/m2) was calculated from the significant wave heights computed by SWAN using the following formula, E=1/8 ρgH_sig^2, where E is wave energy, ρ is the density of water, g is the acceleration due to gravity, and H_sig is the significant wave height. Wave power (in W/m), also called wave energy flux or wave power density, was calculated using the following formula, P_w= Ec_g, where P_w is the wave power or energy flux, and c_g is the group velocity, calculated through the expression c_g= c/2 [1+ 2kD/(sinh⁡(2kD))], where c is the celerity, k is the angular wave number, and D is the water depth. Weighted means of wave height, energy, and power were calculated at each site using the frequency of wind speed and direction conditions determined using NOAA buoy data. Parameter or Variable: Wave Power (WNW Wind Direction) (calculated); Units: Watts per meter; Observation Category: model output; Sampling Instrument: Simulating Waves Nearshore (SWAN); Sampling and Analyzing Method: Estimated wave power from waves generated by winds coming from the West-Northwest (WNW) direction. Units are watts per meter (W/m). Significant wave heights impacting the Great Marsh study sites were estimated using Simulating Waves Nearshore (SWAN). SWAN is a numerical wave model that provides estimates of wave parameters in coastal and estuarine areas from given bottom and wind conditions. For this study’s model, wind conditions were derived from the NOAA data buoy station IOSN3 in Isle of Shoals, New Hampshire, based on the 1996-2020 data record. A 20 m x 20 m bathymetric grid for the study region was created by combining NOAA hydrographic survey data (from NOAA NCEI Bathymetric Data Viewer), 2013-2014 USGS lidar data, and extensive single-beam sonar data collected in the field. To ensure all the sites of interest were exposed to waves in the simulation, the datum of the bathymetric grid was set to MHHW, or 1.47 m above MSL in this region. SWAN was run in stationary mode for 16 different wind directions and for 4 different wind speed bins: 5-10 m/s, 10-15 m/s, 15-20 m/s, and winds faster than 20 m/s, resulting in 64 simulations. Wave energy (in J/m2) was calculated from the significant wave heights computed by SWAN using the following formula, E=1/8 ρgH_sig^2, where E is wave energy, ρ is the density of water, g is the acceleration due to gravity, and H_sig is the significant wave height. Wave power (in W/m), also called wave energy flux or wave power density, was calculated using the following formula, P_w= Ec_g, where P_w is the wave power or energy flux, and c_g is the group velocity, calculated through the expression c_g= c/2 [1+ 2kD/(sinh⁡(2kD))], where c is the celerity, k is the angular wave number, and D is the water depth. Weighted means of wave height, energy, and power were calculated at each site using the frequency of wind speed and direction conditions determined using NOAA buoy data. Parameter or Variable: Wave Power (NW Wind Direction) (calculated); Units: Watts per meter; Observation Category: model output; Sampling Instrument: Simulating Waves Nearshore (SWAN); Sampling and Analyzing Method: Estimated wave power from waves generated by winds coming from the Northwest (NW) direction. Units are watts per meter (W/m). Significant wave heights impacting the Great Marsh study sites were estimated using Simulating Waves Nearshore (SWAN). SWAN is a numerical wave model that provides estimates of wave parameters in coastal and estuarine areas from given bottom and wind conditions. For this study’s model, wind conditions were derived from the NOAA data buoy station IOSN3 in Isle of Shoals, New Hampshire, based on the 1996-2020 data record. A 20 m x 20 m bathymetric grid for the study region was created by combining NOAA hydrographic survey data (from NOAA NCEI Bathymetric Data Viewer), 2013-2014 USGS lidar data, and extensive single-beam sonar data collected in the field. To ensure all the sites of interest were exposed to waves in the simulation, the datum of the bathymetric grid was set to MHHW, or 1.47 m above MSL in this region. SWAN was run in stationary mode for 16 different wind directions and for 4 different wind speed bins: 5-10 m/s, 10-15 m/s, 15-20 m/s, and winds faster than 20 m/s, resulting in 64 simulations. Wave energy (in J/m2) was calculated from the significant wave heights computed by SWAN using the following formula, E=1/8 ρgH_sig^2, where E is wave energy, ρ is the density of water, g is the acceleration due to gravity, and H_sig is the significant wave height. Wave power (in W/m), also called wave energy flux or wave power density, was calculated using the following formula, P_w= Ec_g, where P_w is the wave power or energy flux, and c_g is the group velocity, calculated through the expression c_g= c/2 [1+ 2kD/(sinh⁡(2kD))], where c is the celerity, k is the angular wave number, and D is the water depth. Weighted means of wave height, energy, and power were calculated at each site using the frequency of wind speed and direction conditions determined using NOAA buoy data. Parameter or Variable: Wave Power (NNW Wind Direction) (calculated); Units: Watts per meter; Observation Category: model output; Sampling Instrument: Simulating Waves Nearshore (SWAN); Sampling and Analyzing Method: Estimated wave power from waves generated by winds coming from the North-Northwest (NNW) direction. Units are watts per meter (W/m). Significant wave heights impacting the Great Marsh study sites were estimated using Simulating Waves Nearshore (SWAN). SWAN is a numerical wave model that provides estimates of wave parameters in coastal and estuarine areas from given bottom and wind conditions. For this study’s model, wind conditions were derived from the NOAA data buoy station IOSN3 in Isle of Shoals, New Hampshire, based on the 1996-2020 data record. A 20 m x 20 m bathymetric grid for the study region was created by combining NOAA hydrographic survey data (from NOAA NCEI Bathymetric Data Viewer), 2013-2014 USGS lidar data, and extensive single-beam sonar data collected in the field. To ensure all the sites of interest were exposed to waves in the simulation, the datum of the bathymetric grid was set to MHHW, or 1.47 m above MSL in this region. SWAN was run in stationary mode for 16 different wind directions and for 4 different wind speed bins: 5-10 m/s, 10-15 m/s, 15-20 m/s, and winds faster than 20 m/s, resulting in 64 simulations. Wave energy (in J/m2) was calculated from the significant wave heights computed by SWAN using the following formula, E=1/8 ρgH_sig^2, where E is wave energy, ρ is the density of water, g is the acceleration due to gravity, and H_sig is the significant wave height. Wave power (in W/m), also called wave energy flux or wave power density, was calculated using the following formula, P_w= Ec_g, where P_w is the wave power or energy flux, and c_g is the group velocity, calculated through the expression c_g= c/2 [1+ 2kD/(sinh⁡(2kD))], where c is the celerity, k is the angular wave number, and D is the water depth. Weighted means of wave height, energy, and power were calculated at each site using the frequency of wind speed and direction conditions determined using NOAA buoy data. Parameter or Variable: Flood Current Velocity (calculated); Units: Meters per second; Observation Category: model output; Sampling Instrument: Delft3D; Sampling and Analyzing Method: Ebb and flood current velocities were extracted from hydrodynamic models previously developed and calibrated for tidal harmonics using field observations [1,2]. Using the calibration simulations, which covered a typical 30-day simulation, peak flood, and ebb velocities were extracted during spring tide conditions. Velocities were extracted at the nearest “wet” model grid cell adjacent to the sites where retreat rates were measured, to eliminate wet-dry perturbations from influencing tidal currents. Peak ebb and peak flood velocities were then averaged over the three largest tidal excursions during spring tide conditions and were subsequently used in correlations with marsh retreat data. [1] FitzGerald, D.M., Hughes, Z. J., Georgiou, I. Y., Black, S., and Novak, A. 2020. Enhanced, climate driven sedimentation on salt marshes. Geophys. Res. Lett., 46. https://doi.org/10.1029/2019GL086737 [2] FitzGerald, D.M., et al. (2022). Following the Sand Grains. J. Mar. Sci. Eng., 10(5), 631. https://doi.org/10.3390/jmse10050631 Parameter or Variable: Ebb Current Velocity (calculated); Units: Meters per second; Observation Category: model output; Sampling Instrument: Delft3D; Sampling and Analyzing Method: Ebb and flood current velocities were extracted from hydrodynamic models previously developed and calibrated for tidal harmonics using field observations [1,2]. Using the calibration simulations, which covered a typical 30-day simulation, peak flood, and ebb velocities were extracted during spring tide conditions. Velocities were extracted at the nearest “wet” model grid cell adjacent to the sites where retreat rates were measured, to eliminate wet-dry perturbations from influencing tidal currents. Peak ebb and peak flood velocities were then averaged over the three largest tidal excursions during spring tide conditions and were subsequently used in correlations with marsh retreat data. [1] FitzGerald, D.M., Hughes, Z. J., Georgiou, I. Y., Black, S., and Novak, A. 2020. Enhanced, climate driven sedimentation on salt marshes. Geophys. Res. Lett., 46. https://doi.org/10.1029/2019GL086737 [2] FitzGerald, D.M., et al. (2022). Following the Sand Grains. J. Mar. Sci. Eng., 10(5), 631. https://doi.org/10.3390/jmse10050631 Parameter or Variable: Channel Curvature (measured); Units: 1 / kilometer; Observation Category: satellite; Sampling Instrument: Satellite Imagery; Sampling and Analyzing Method: Estimated measure of tidal channel curvature adjacent to the study sites. Units are 1/kilometer (1/km).Channel curvature was calculated as the reciprocal of radius of curvature, which is measured as the radius of an arc the best fits the curve. Radius of curvature for tidal channels adjacent to each site was measured by approximating channel curves based on satellite imagery and drawing circle arcs. A straight channel has an infinite radius of curvature, and thus a channel curvature of 0. Channels that are concave at the study site have a positive curvature value while channels that are convex have a negative curvature value. Parameter or Variable: Site (measured); Units: none; Observation Category: other; Sampling Instrument: none; Sampling and Analyzing Method: Name of station/site of interest. Parameter or Variable: Longitude (measured); Units: Decimal Degrees; Observation Category: in situ; Sampling Instrument: GPS; Sampling and Analyzing Method: Longitude of site of interest, measured using Garmin GPS. Parameter or Variable: Latitude (measured); Units: Decimal Degrees; Observation Category: in situ; Sampling Instrument: GPS; Sampling and Analyzing Method: Latitude of site of interest, measured using Garmin GPS. Parameter or Variable: Number of Transects Used (calculated); Units: none; Observation Category: other; Sampling Instrument: none; Sampling and Analyzing Method: Number of cross-shoreline transects used in Digital Shoreline Analysis System (DSAS) to calculate the retreat rates of the surveyed shorelines at each site. Parameter or Variable: Length of Shoreline Surveyed (measured); Units: meter; Observation Category: other; Sampling Instrument: RTK-GPS; Sampling and Analyzing Method: The length of the shoreline surveyed at each site using RTK-GPS. Parameter or Variable: Date of Shoreline Survey 1 (measured); Units: nanonewton; Observation Category: other; Sampling Instrument: none; Sampling and Analyzing Method: Date of the first RTK-GPS shoreline survey of the site. Parameter or Variable: Date of Shoreline Survey 2 (measured); Units: none; Observation Category: other; Sampling Instrument: none; Sampling and Analyzing Method: Date of the second RTK-GPS shoreline survey of the site. Parameter or Variable: Date of Shoreline Survey 3 (measured); Units: none; Observation Category: other; Sampling Instrument: none; Sampling and Analyzing Method: Date of the third RTK-GPS shoreline survey of the site. Parameter or Variable: Date of Shoreline Survey 4 (measured); Units: nanonewton; Observation Category: other; Sampling Instrument: none; Sampling and Analyzing Method: Date of the fourth (if applicable) RTK-GPS shoreline survey of the site. If no fourth survey was completed at the site, data show "n/a" asNeeded Metadata are developed, maintained and distributed by NCEI. Updates are performed as needed to maintain currentness. NOAA National Centers for Environmental Information custodian GPS GPS Global Positioning System receiver satellite-based instrument used for geo-location, positioning and navigation satellite sensor - general satellite sensor - general A generic class used for unknown satellite sensor type, or datasets consisting of blended, merged, or otherwise mixed observations from multiple satellite sensor types