Shoreline change monitoring at Assateague Island National Seashore: 2005-2010 trend report
Psuty NP, Silveira TM, Soda D. 2011. Shoreline change monitoring at Assateague Island National Seashore: 2005-2010 trend report. Natural Resource Technical Report. NPS/NCBN/NRTR—2011/509. National Park Service, Natural Resource Stewardship and Science. Fort Collins, Colorado
This Trend Report documents the collection of shoreline position data and describes the variation that has occurred during the period from Spring 2005 to Spring 2010 at Assateague Island National Seashore, as called for in the Northeast Coastal and Barrier Network’s protocol on shoreline monitoring (Psuty, et al., 2010). The changes in shoreline position are generally descriptive of the seasonal contrasts (lower energetics in the summer period versus higher energetics in the winter period) that support sediment accumulation during summer and erosion during the winter. However, there are many natural variables and cultural events that affect the gains and losses of sediment and the displacements of the beach, especially at the northern and southern termini of the Assateague Barrier Island. Periodic dredging of the Ocean City Inlet alters the natural supply of sediment reaching the island and also deposits sediment in the nearshore environment to augment the sediment budget. Over the 5-year period, the Maryland portion of Assateague Island had an average inland displacement of -6.38 m, with the northern area experiencing persistent erosion. Seasonal average displacements varied from -17.32 m (Spring 2006-Fall 2006) to +13.58 (Fall 2005-Spring 2006). Mean changes for the entire barrier island were affected by the lengthy southerly extension at Tom’s Cove Hook that tempered the general loss to create a -5-year mean of -2.26 m and seasonal displacements that varied from -18.24 m (Spring 2006-Fall 2006) to +13.43 m (Fall 2007-Spring 2008). Persistent erosion downdrift of Ocean City Inlet and along the ocean shoreline at Tom’s Cove are areas of special concern because of washover and breach potential. That said, this is a short-term data set that has a lot of temporal and spatial variation. Continued monitoring of the shoreline position is providing a basis for identifying vectors of change along Assateague barrier island.
- Type
- Published Report
- Authors
- Psuty, Norbert; Silveira, Tanya; Soda, Daniel
- Date of Issue
- 2011-11
- Publisher
- National Park Service, Natural Resource Stewardship and Science
- Units
- ASIS , NCBN , NRSS
- Keywords
- Assateague Island National Seashore, Northeast Coastal and Barrier Network, shoreline monitoring, shoreline position change