| Title: New Hampshire Beach Shoreline Change | |
| Time Period of Content: 1855 - 2015 | Initial Publication Date: 1/29/2016 |
| Originator: New Hampshire Geological Survey, New Hampshire Department of Environmental Services | |
| Abstract: To assess both the stability (landward or seaward migration) of the New Hampshire coastline and volumetric changes of the beaches, short-term changes (years) were analyzed using lidar data and long-term trends (decades) were analyzed using shorelines drawn from charts and orthophography. Multiple vintages of airborne lidar spanning the last decade and a half were analyzed to detect changes in volume of sand and gravel beaches of New Hampshire's coast using a simple DEM of Difference (DOD). The trend of the shoreline position was determined for shore-perpendicular transects using the Digital Shoreline Analysis System (DSAS). The data are distributed as a geodatabase with 18 feature classes. They include: 9 DoDs clipped to the landward area of the beach named as DoD_(latest year)_(earliest year)_clip, a series of beach polygons used for the clipping, and a single shoreline feature class (shorelines_merge) that represents shoreline position merged from 23 individual shoreline representations dating back to the mid-1800's. For detailed information on the content of the database, please see two related documents - BOEM_Rept_Change_Analysis_Olson_D20160129_NFO_final.pdf, which is the final report on the project as prepared for the sponsoring agency (Bureau of Ocean Energy Management), and BeachShorelineChangeNotes.doc, which provides additional detailed information on the data sources used for the mapping and the processing methodology. The distribution geodatabase contains the primary project results. The full project geodatabase may be acquired by contacting Frederick Chormann, NH State Geologist (see Point of Contact section below). | |
| Theme Keywords: biota, coast, coastline, beaches, shoreline, shoreline change, accretion, erosion | |
| Full Metadata and Data Download | |