Lead Agency:
Earth Systems Research Center

Primary Contact:
Cameron Wake

Start Date - End Date
01/01/2011 - 12/30/2012

Description:
The text below is modified and updated from the Sea Level Rise chapter in: Wake et al. (2011) Climate Change in the Piscataqua/Great Bay Region: Past, Present, and Future. http://www.climatesolutionsne.org

Sea Level Rise in Coastal NH

The results of the analysis discussed in detail below indicate that we can expect the 100-year flood elevation at Fort Point in New Castle, NH to increase from a current elevation of 11.2 feet to a range of 12.4 to 13.1 feet by 2050, and to a range of 14.0 to 17.8 feet by 2100. Therefore, even under low greenhouse gas emissions scenarios, we can expect the 100-year flood elevation to increase several feet over the next 90 years. This increase in the 100-year flood elevation will result in more severe flooding in coastal New Hampshire in the future.

To illustrate the impact of the higher 100-year flood elevations in the future, we have produced a series of ten maps that cover the NH seacoast, Piscataqua River, and Great Bay. These maps show stillwater flood depths over land for flood elevations of six feet, nine feet, and twelve feet above mean higher high water (MHHW). (MHHW is the average of the higher high water elevation of each tidal day; values are provided by NOAA.)

These maps are based on detailed LiDAR (Light Detection and Ranging) topographic data that was collected during the spring of 2011. Note that the maps are provided for discussion and research purposes only. It is not appropriate to use the maps for detailed analysis (i.e., at the parcel level). Please contact Cameron Wake at Climate Solutions New England http://climatesolutionsne.org for additional information on methodology and limitations.