Global Climate Change Impacts in the United States 2009 Report Legacy site

Abstract  With dense population and development along its coastline, the northeastern United States is, at present, highly vulnerable to coastal flooding. At five sea level stations in the United States, from Massachusetts to New Jersey, sea level rise (SLR) trends and tidal effects were removed from the hourly sea level time series and then frequency analysis was performed on the positive remaining anomalies that represent storm surge heights. Then using eustatic SLR estimates for lower and higher greenhouse gas emissions scenarios and assumed trends in local sea level rise, new recurrence intervals were determined for future storm surges. Under the higher emissions scenario, by 2050, the elevation of the 2005 100-year event may be equaled or exceeded at least every 30 years at all sites. In more exposed US cities such as Boston, Massachusetts and Atlantic City, New Jersey, this could occur at the considerably higher frequency of every 8 years or less. Under the lower emissions scenario, by 2050, the elevation of the 2005 100-year event may be equaled or exceeded at least every 70 years at all sites. In Boston and Atlantic City, this could occur every 30 years or less.