These files contain topographic profiles collected at ASIS through the 2020 field season

These files contain topographic profiles collected at ASIS through the 2022 field season

These files contain topographic profiles collected at ASIS through the Spring 2025 field season

These files contain topographic profiles collected at ASIS through the Spring 2025 field season

The dynamic nature of coastal areas is a defining characteristic, influencing nearly every aspect of their ecology. Fundamentally disturbance driven systems, coastal shorelines and their endemic biota are continually shaped by physical forces on a time scale vastly accelerated in comparison to mainland systems. Because of the rapid pace and scope of change, long term monitoring is crucial towards understanding natural shoreline conditions as well as anthropogenic influences. These data represent a series of mean high-water shorelines collected at Assateague Island National Seashore (ASIS), Cape Cod National Seashore (CACO), Fire Island National Seashore (FIIS), Gateway National Recreation Area (GATE), George Washington Birthplace National Monument (GEWA), and Sagamore Hill National Historic Site (SAHI). The features have been assembled/collected in support of the Northeast Coastal & Barrier Inventory and Monitoring Network's Ocean Shoreline Position Monitoring Program. Surveys along the ocean shoreline were collected by driving a 4-wheel drive vehicle or walking at a relatively constant speed along the identified high tide swash line. For the purposes of this monitoring program, the actual ocean "shoreline" was defined as the average position of the most recent high tide, evidenced by the obvious wet/dry sand line or deposited wrack. The GPS/GNSS receiver was configured to record positions at a very short interval (at least 1 position every 10 meters) for the best representation of the shoreline position. Depending on the time of year and intended purpose, some surveys contain ocean, inlet and bay shorelines, while some surveys only contain ocean shorelines.

These files contain topographic profiles collected at GATE through the 2022 field season

These data represent a series of mean-high water shorelines collected at Assateague Island National Seashore (ASIS), appended into one spatial dataset. The features have been assembled / collected in support of the Northeast Coastal & Barrier Inventory and Monitoring Network's Ocean Shoreline Position Monitoring Program. Surveys along the ocean shoreline were collected by driving a 4-wheel drive vehicle or walking at a relatively constant speed along the identified high tide swash line. For the purposes of this monitoring program, the actual ocean "shoreline" was defined as the average position of the most recent high tide, evidenced by the obvious wet/dry sand line or deposited wrack. The GPS/GNSS receiver was configured to record positions at a very short interval (at least 1 position every 10 meters) for the best representation of the shoreline position. Depending on the time of year and intended purpose, some surveys contain ocean, inlet and bay shorelines, while some surveys only contain ocean shorelines. Additionally, some surveys collected prior to 2003 do not contain FGDC-compliant metadata records. This dataset contains shoreline features collect between Winter of 1994 and Spring 2025.

These data represent a series of mean high water shorelines collected at Assateague Island National Seashore (ASIS), appended into one spatial dataset. The features have been assembled / collected in support of the Northeast Coastal & Barrier Inventory and Monitoring Network's Ocean Shoreline Position Monitoring Program. Surveys along the ocean shoreline were collected by driving a 4-wheel drive vehicle or walking at a relatively constant speed along the identified high tide swash line. For the purposes of this monitoring program, the actual ocean "shoreline" was defined as the average position of the most recent high tide, evidenced by the obvious wet/dry sand line or deposited wrack. The GPS/GNSS receiver was configured to record positions at a very short interval (at least 1 position every 10 meters) for the best representation of the shoreline position. Depending on the time of year and intended purpose, some surveys contain ocean, inlet and bay shorelines, while some surveys only contain ocean shorelines. Additionally, some surveys collected prior to 2003 do not contain FGDC-compliant metadata records. This dataset contains shoreline features collect between August of 1993 and Fall 2022.

Cross-island profile monitoring began in 1995. Elevations are collected every 10m and at all significant elevation changes along transects that run at a 291/111 degree azimuth. Between 1995-2003, elevations were collected using a NIKON total station and referenced to the NAVD88 datum. Between 2004-2009, a Trimble 5700 RTK system was used. From 2010-2014, a Trimble R8 RTK system was used. In 2015 and 2016, both Trimble R10 and Trimble R8 RTK systems were used, and elevations were referenced to NAVD88 datum. Starting in 2017 data were collected using a Trimble R10 using streaming from the new MDAI GNSS CORS. These data are used to monitor and understand the dynamics of barrier islands and their associated dune complexes.

These files contain topographic profiles collected at GATE through the 2023 field season