Snyder, Alexander G.

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Bathymetric measurements of Little Holland Tract, Sacramento-San Joaquin Delta, California, 2015, from personal watercraft

Bathymetric data were collected by the U.S. Geological Survey (USGS) in 2015 for Little Holland Tract in the Sacramento-San Joaquin River Delta, California. The data were collected using a personal watercraft (PWC) platform that consisted of Trimble R7 Global Navigation Satellite System (GNSS) receivers with Zephyr 2 antennas, combined with Odom Echotrac CV-100 single-beam echosounders and 200 kHz transducers. Data was post-processed to remove spurious data points. Raw depths were converted to ellipsoid ...

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Digital elevation model of Little Holland Tract, Sacramento-San Joaquin Delta, California, 2015

This product is a digital elevation model (DEM) for the Little Holland Tract in the Sacramento-San Joaquin River Delta, California based on U.S. Geological Survey (USGS)-collected elevation data, merged with existing topographic and bathymetric elevation data. The USGS collected topographic and bathymetric elevation data in 2015, using a combination of methods. Topographic and shallow-water bathymetric data were collected on foot using a global positioning system (GPS) backpack platform that consisted of ...

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Topographic measurements of Little Holland Tract, Sacramento-San Joaquin Delta, California, 2015, using backpack GPS

Topographic data were collected by the U.S. Geological Survey (USGS) in 2015 for Little Holland Tract in the Sacramento-San Joaquin River Delta, California. The data were collected on foot using a global positioning system (GPS) backpack platform that consisted of survey-grade Trimble R10 and R7 global navigation satellite system (GNSS) receivers with Zephyr 2 antennas. Orthometric elevations relative to NAVD88 were computed using the National Geodetic Survey Geoid12a, and the final data were projected in ...

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Digital Shoreline Analysis System (DSAS) version 4.4 transects with long-term linear regression rate calculations for the exposed north coast of Alaska, from Icy Cape to Cape Prince of Wales

This dataset consists of long-term (less than 68 years) shoreline change rates for the exposed coast of the north coast of Alaska from Icy Cape to Cape Prince of Wales. Rate calculations were computed within a GIS using the Digital Shoreline Analysis System (DSAS) version 4.4, an ArcGIS extension developed by the U.S. Geological Survey. Rates of shoreline change were calculated using a linear regression rate-of-change (lrr) method based on available shoreline data between 1948 and 2016. A reference baseline ...

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Digital Shoreline Analysis System (DSAS) version 4.4 transects with long-term linear regression rate calculations for the sheltered north coast of Alaska, from Icy Cape to Cape Prince of Wales

This dataset consists of long-term (less than 68 years) shoreline change rates for the sheltered north coast of Alaska from Icy Cape to Cape Prince of Wales. Rate calculations were computed within a GIS using the Digital Shoreline Analysis System (DSAS) version 4.4, an ArcGIS extension developed by the U.S. Geological Survey. Rates of shoreline change were calculated using a linear regression rate-of-change (lrr) method based on available shoreline data between 1948 and 2016. A reference baseline was used ...

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Digital Shoreline Analysis System (DSAS) version 4.4 transects with short-term end-point rate-of-change calculations for the exposed north coast of Alaska, from Icy Cape to Cape Prince of Wales

This dataset consists of short-term (less than 37 years) shoreline change rates for the exposed coast of the north coast of Alaska from Icy Cape to Cape Prince of Wales. Rate calculations were computed within a GIS using the Digital Shoreline Analysis System (DSAS) version 4.4, an ArcGIS extension developed by the U.S. Geological Survey. Rates of shoreline change were calculated using an end point rate-of-change (epr) method based on available shoreline data between 1980 and 2016. A reference baseline was ...

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Digital Shoreline Analysis System (DSAS) version 4.4 transects with short-term end-point rate-of-change calculations for the sheltered north coast of Alaska, from Icy Cape to Cape Prince of Wales

This dataset consists of short-term (less than 37 years) shoreline change rates for the sheltered north coast of Alaska from Icy Cape to Cape Prince of Wales. Rate calculations were computed within a GIS using the Digital Shoreline Analysis System (DSAS) version 4.4, an ArcGIS extension developed by the U.S. Geological Survey. Rates of shoreline change were calculated using an end point rate-of-change (epr) method based on available shoreline data between 1980 and 2016. A reference baseline was used as the ...

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Digital Shoreline Analysis System (DSAS) version 4.4 transects with short-term linear regression rate calculations for the exposed north coast of Alaska, from Icy Cape to Cape Prince of Wales

This dataset consists of short-term (less than 37 years) shoreline change rates for the north coast of Alaska from Icy Cape to Cape Prince of Wales. Rate calculations were computed within a GIS using the Digital Shoreline Analysis System (DSAS) version 4.4, an ArcGIS extension developed by the U.S. Geological Survey. Rates of shoreline change were calculated using a linear regression rate-of-change (lrr) method based on available shoreline data between 1980s and 2016. A reference baseline was used as the ...

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Offshore baseline generated to calculate shoreline change rates for the north coast of Alaska, Icy Cape to Cape Prince of Wales

This dataset includes a reference baseline used by the Digital Shoreline Analysis System (DSAS) to calculate rate-of-change statistics for the exposed coast of Alaska from Icy Cape and Cape Prince Wales for the time period 1948 to 2016. This baseline layer serves as the starting point for all transects cast by the DSAS application and can be used to establish measurement points used to calculate shoreline-change rates.

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Shorelines from 1948 to 2016 for the north coast of Alaska, Icy Cape to Cape Prince Wales used in shoreline change analysis

This dataset includes shorelines that span 68 years, from 1948 to 2016, for the north coast of Alaska from Icy Cape to Cape Prince of Wales. Shorelines were compiled from topographic survey sheets (T-sheets; National Oceanic and Atmospheric Administration (NOAA)) and aerial orthophotographs (U.S. Geological Survey (USGS) and Alaska High Altitude Photography (AHAP)). Historical shoreline positions serve as easily understood features that can be used to describe the movement of beaches through time. These ...

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Nearshore bathymetry data from the Unalakleet River mouth, Alaska, 2019

This data release presents nearshore bathymetry data collected at the mouth of the Unalakleet River in Alaska, near the city of Unalakleet. The data were collected in August 2019 by the U.S. Geological Survey, Pacific Coastal and Marine Science Center. Nearshore bathymetry was measured along survey lines from the shore to a depth of approximately -7.4 m NAVD88 and in a portion of the estuary closest to the mouth. Bathymetry data were collected using small boat equipped with a single-beam sonar system and ...

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Nearshore bathymetry data from northern Monterey Bay, California, March 2015

This part of the data release presents bathymetry data from northern Monterey Bay, California collected in March 2015 using two personal watercraft (PWCs). The PWCs were equipped with single-beam echosounders and survey-grade global navigation satellite system (GNSS) receivers.

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Nearshore bathymetry data from northern Monterey Bay, California, March 2016

This part of the data release presents bathymetry data from northern Monterey Bay, California collected in March 2016 using two personal watercraft (PWCs). The PWCs were equipped with single-beam echosounders and survey-grade global navigation satellite system (GNSS) receivers.

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Nearshore bathymetry data from northern Monterey Bay, California, March 2017

This part of the data release presents bathymetry data from northern Monterey Bay, California collected in March 2017 using personal watercraft (PWC). The survey vessels were equipped with single-beam echosounders and survey-grade global navigation satellite system (GNSS) receivers.

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Nearshore bathymetry data from northern Monterey Bay, California, October 2014

This part of the data release presents bathymetry data from northern Monterey Bay, California collected in October 2014 using two personal watercraft (PWCs). The PWCs were equipped with single-beam echosounders and survey-grade global navigation satellite system (GNSS) receivers.

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Nearshore bathymetry data from northern Monterey Bay, California, September 2016

This part of the data release presents bathymetry data from northern Monterey Bay, California collected in September 2016 using a personal watercraft (PWC) and small boat. The survey vessels were equipped with single-beam echosounders and survey-grade global navigation satellite system (GNSS) receivers.

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Nearshore bathymetry data from northern Monterey Bay, California, September 2017

This part of the data release presents bathymetry data from northern Monterey Bay, California collected in September 2017 using two personal watercraft (PWCs). The PWCs were equipped with single-beam echosounders and survey-grade global navigation satellite system (GNSS) receivers.

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Nearshore bathymetry data from northern Monterey Bay, California, September and October 2015

This part of the data release presents bathymetry data from northern Monterey Bay, California collected in September and October 2015 using two personal watercraft (PWCs). The PWCs were equipped with single-beam echosounders and survey-grade global navigation satellite system (GNSS) receivers.

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Terrestrial lidar data from northern Monterey Bay, California, March 2015

This part of the data release presents topography data from northern Monterey Bay, California collected in March 2015 with a terrestrial lidar scanner.

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Terrestrial lidar data from northern Monterey Bay, California, March 2016

This part of the data release presents topography data from northern Monterey Bay, California collected in March 2016 with a terrestrial lidar scanner.

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Terrestrial lidar data from northern Monterey Bay, California, March 2017

This part of the data release presents topography data from northern Monterey Bay, California collected in March 2017 with a terrestrial lidar scanner.

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Terrestrial lidar data from northern Monterey Bay, California, October 2016

This part of the data release presents topography data from northern Monterey Bay, California collected in October 2016 with a terrestrial lidar scanner.

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Terrestrial lidar data from northern Monterey Bay, California, September 2015

This part of the data release presents topography data from northern Monterey Bay, California collected in September 2015 with a terrestrial lidar scanner.

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Terrestrial lidar data from northern Monterey Bay, California, September 2017

This part of the data release presents topography data from northern Monterey Bay, California collected in September 2017 with a terrestrial lidar scanner.

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Digital surface models of the north coast of Barter Island, Alaska acquired on July 01 2014, September 07 2014, and July 05 2015 (GeoTIFF image)

Digital surface elevation models (DSMs) of the coastline of Barter Island, Alaska derived from aerial photographs collected on July 01 2014, September 07 2014, and July 05 2015. Aerial photographs and coincident elevation data were processed using Structure-from-Motion (SfM) photogrammetric techniques. These files are single-band, 32-bit floating point DSMs (digital surface models) that represent surface elevations of buildings, vegetation, and uncovered ground surfaces in meters with 23 cm ground sample ...

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Elevation point clouds of the north coast of Barter Island, Alaska acquired July 01 2014, September 07 2014, and July 05 2015 (LAZ file)

Six elevation point cloud files in LAZ format (compressed LAS binary data) are included in this data release: 3 raw point clouds of unclassified and unedited points and 3 modified point clouds that were spatially shifted and edited to remove outliers and spurious elevation values associated with moving water surfaces. An XYZ coordinate shift was applied to each data set in order to register the data sets to an earth-based datum established from surveyed ground control points. Points are unclassified and ...

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Surveyed ground control and elevation checkpoints acquired at Barter Island, Alaska, 2014-2016

Ground control points and checkpoints were collected during Global Positioning System (GPS) surveys conducted between September 6, 2014 and September 18, 2016 along the northern coast of Barter Island, Alaska. Data were acquired and post-processed using precise positioning and used to co-register and assess accuracy of photogrammetric data sets.

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Observations of tsunami and runup heights in Santa Cruz Harbor and surrounding beaches from the 2022 Hunga Tonga-Hunga Ha'apai tsunami

The 14 January 2022 eruption of Tonga Hunga-Tonga Ha'apai volcano generated tsunamis that impacted the west coast of the United States on the morning of 15 January 2022. This data release presents runup heights and tsunami heights collected by the U.S. Geological Survey (USGS) and the California Geological Survey (CGS) during surveys at the Santa Cruz Harbor and beaches in Santa Cruz County, California, on January 19th and 20th, 2022 (USGS Field Activity 2022-607-FA). Evidence of tsunami inundation included ...

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Digital elevation models (DEMs) of northern Monterey Bay, California, March 2015

This part of the data release presents digital elevation models (DEMs) derived from bathymetry and topography data of northern Monterey Bay, California collected in March 2015. Bathymetry data were collected using two personal watercraft (PWCs), each equipped with single-beam echosounders and survey-grade global navigation satellite system (GNSS) receivers. Topography data were collected on foot with GNSS receivers mounted on backpacks and with an all-terrain vehicle (ATV) using a GNSS receiver mounted at a ...

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Digital elevation models (DEMs) of northern Monterey Bay, California, March 2016

This part of the data release presents digital elevation models (DEMs) derived from bathymetry and topography data of northern Monterey Bay, California collected in March 2016. Bathymetry data were collected using two personal watercraft (PWCs), each equipped with single-beam echosounders and survey-grade global navigation satellite system (GNSS) receivers. Topography data were collected on foot with GNSS receivers mounted on backpacks and with an all-terrain vehicle (ATV) using a GNSS receiver mounted at a ...

Info
Digital elevation models (DEMs) of northern Monterey Bay, California, March 2017

This part of the data release presents digital elevation models (DEMs) derived from bathymetry and topography data of northern Monterey Bay, California collected in March 2017. Bathymetry data were collected using two personal watercraft (PWCs), each equipped with single-beam echosounders and survey-grade global navigation satellite system (GNSS) receivers. Topography data were collected on foot with GNSS receivers mounted on backpacks and with an all-terrain vehicle (ATV) using a GNSS receiver mounted at a ...

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Digital elevation models (DEMs) of northern Monterey Bay, California, October 2014

This part of the data release presents digital elevation models (DEMs) derived from bathymetry and topography data of northern Monterey Bay, California collected in October 2014. Bathymetry data were collected using two personal watercraft (PWCs), each equipped with single-beam echosounders and survey-grade global navigation satellite system (GNSS) receivers. Topography data were collected on foot with GNSS receivers mounted on backpacks and with an all-terrain vehicle (ATV) using a GNSS receiver mounted at ...

Info
Digital elevation models (DEMs) of northern Monterey Bay, California, September 2017

This part of the data release presents digital elevation models (DEMs) derived from bathymetry and topography data of northern Monterey Bay, California collected in September 2017. Bathymetry data were collected using two personal watercraft (PWCs), each equipped with single-beam echosounders and survey-grade global navigation satellite system (GNSS) receivers. Topography data were collected on foot with GNSS receivers mounted on backpacks and with an all-terrain vehicle (ATV) using a GNSS receiver mounted ...

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Digital elevation models (DEMs) of northern Monterey Bay, California, September and October 2015

This part of the data release presents digital elevation models (DEMs) derived from bathymetry and topography data of northern Monterey Bay, California collected in September and October 2015. Bathymetry data were collected using two personal watercraft (PWCs), each equipped with single-beam echosounders and survey-grade global navigation satellite system (GNSS) receivers. Topography data were collected on foot with GNSS receivers mounted on backpacks and with an all-terrain vehicle (ATV) using a GNSS ...

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Digital elevation models (DEMs) of northern Monterey Bay, California, September and October 2016

This part of the data release presents digital elevation models (DEMs) derived from bathymetry and topography data of northern Monterey Bay, California collected in September and October 2016. Bathymetry data were collected using a personal watercraft (PWC) and small boat, each equipped with single-beam echosounders and survey-grade global navigation satellite system (GNSS) receivers. Topography data were collected on foot with GNSS receivers mounted on backpacks and with an all-terrain vehicle (ATV) using ...

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Orthophotomosaic image (natural color) of the north coast of Barter Island, Alaska acquired on July 01 2014 (GeoTIFF image, 19-cm resolution)

Aerial photographs were collected from a small, fixed-wing aircraft over the coast of Barter Island, Alaska on July 01 2014, September 07 2014. Precise aircraft position information and structure-from-motion photogrammetric methods were combined to derive a high-resolution orthophotomosaic. This orthophotomosaic contain 3-band, 8-bit, unsigned raster data (red/green/blue; file format-GeoTIFF) with a ground sample distance (GSD) resolution of 19 cm. The file employs Lempel-Ziv-Welch (LZW) compression. This ...

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Orthophotomosaic image (natural color) of the north coast of Barter Island, Alaska acquired on September 07 2014 (GeoTIFF image; 11-cm resolution)

Aerial photographs were collected from a small, fixed-wing aircraft over the coast of Barter Island, Alaska on September 07 2014. Precise aircraft position information and structure-from-motion photogrammetric methods were combined to derive a high-resolution orthophotomosaic. This orthophotomosaic contain 3-band, 8-bit, unsigned raster data (red/green/blue; file format-GeoTIFF) with a ground sample distance (GSD) resolution of 11 cm. The file employs Lempel-Ziv-Welch (LZW) compression. This ...

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Orthophotomosaic images (natural color) of the north coast of Barter Island, Alaska acquired on July 05 2015 (GeoTIFF image; 8-cm resolution)

Aerial photographs were collected from a small, fixed-wing aircraft over the coast of Barter Island, Alaska on July 05 2015. Precise aircraft position information and structure-from-motion photogrammetric methods were combined to a derive high-resolution orthophotomosaic. This orthophotomosaic contain 3-band, 8-bit, unsigned raster data (red/green/blue; file format-GeoTIFF) with a ground sample distance (GSD) resolution of 8 cm. The file employs Lempel-Ziv-Welch (LZW) compression. This orthophotomosaic was ...

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Topography data from northern Monterey Bay, California, March 2015

This part of the data release presents topography data from northern Monterey Bay, California collected in March 2015. Topography data were collected on foot with survey-grade global navigation satellite system (GNSS) receivers mounted on backpacks and with an all-terrain vehicle (ATV) using a GNSS receiver mounted at a measured height above the ground.

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Topography data from northern Monterey Bay, California, March 2016

This part of the data release presents topography data from northern Monterey Bay, California collected in March 2016. Topography data were collected on foot with survey-grade global navigation satellite system (GNSS) receivers mounted on backpacks and with an all-terrain vehicle (ATV) using a GNSS receiver mounted at a measured height above the ground.

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Topography data from northern Monterey Bay, California, March 2017

This part of the data release presents topography data from northern Monterey Bay, California collected in March 2017. Topography data were collected on foot with survey-grade global navigation satellite system (GNSS) receivers mounted on backpacks and with an all-terrain vehicle (ATV) using a GNSS receiver mounted at a measured height above the ground.

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Topography data from northern Monterey Bay, California, October 2014

This part of the data release presents topography data from northern Monterey Bay, California collected in October 2014. Topography data were collected on foot with survey-grade global navigation satellite system (GNSS) receivers mounted on backpacks and with an all-terrain vehicle (ATV) using a GNSS receiver mounted at a measured height above the ground.

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Topography data from northern Monterey Bay, California, September 2016

This part of the data release presents topography data from northern Monterey Bay, California collected in September 2016. Topography data were collected on foot with survey-grade global navigation satellite system (GNSS) receivers mounted on backpacks and with an all-terrain vehicle (ATV) using a GNSS receiver mounted at a measured height above the ground.

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Topography data from northern Monterey Bay, California, September 2017

This part of the data release presents topography data from northern Monterey Bay, California collected in September 2017. Topography data were collected on foot with survey-grade global navigation satellite system (GNSS) receivers mounted on backpacks and with an all-terrain vehicle (ATV) using a GNSS receiver mounted at a measured height above the ground.

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Topography data from northern Monterey Bay, California, September and October 2015

This part of the data release presents topography data from northern Monterey Bay, California collected in September and October 2015. Topography data were collected on foot with survey-grade global navigation satellite system (GNSS) receivers mounted on backpacks and with an all-terrain vehicle (ATV) using a GNSS receiver mounted at a measured height above the ground.

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