Global Sea Level Rise is a Local Threat
Over the next century, sea level rise within the United States is expected to vary between -6 to 4 feet, depending on location.
The Intergovernmental Panel on Climate Change (IPCC) estimates that the global average sea level will rise between 0.6 to 2 feet (0.18 to 0.59 meters) in the next century (IPCC 2007). However, climate models, satellite data, and hydrographic observations demonstrate that sea level is not rising uniformly around the world. Depending on the region, sea level might be projected to rise several times the global mean rise or can actually fall.
Local sea level change, which is of more direct concern to coastal communities, is a combination of the rise in sea level and the change in land elevation. Some areas of the country, such as areas within Alaska, are actually experiencing a lowering of local sea level due to regional uplift of land caused by the retreat of glaciers. Put simply, the land is rising faster than the sea level. In contrast, areas along the Gulf of Mexico coast are experiencing land subsidence at varying rates, accelerating the rate of seal level rise (NOAA 2010c). The map below displays local trends in sea level, with arrows representing the direction and magnitude of change. Click the image to demo the tool.
U.S. Geological Survey National Assessment of Coastal Vulnerability to Sea Level Rise
NOAA Tides and Currents - Sea Level Online
NOAA Climate Services
U.S. Global Change Research Program