A scientist at a non-profit research group in Princeton, NJ told USA Today that 316 coastal cities and towns in the United States will face partial submergence due to a four-foot seawater rise locked in by prior greenhouse gas emissions. The largest cities threatened by rising sea levels are Miami, Virginia Beach, Jacksonville and Sacremento. Recent published research indicates that warming already occurring is irreversible and will persist for thousands of years. Higher temperatures melting the ice in Greenland and Antarctica and oceanic thermal expansion will cause the seas to rise. The rate at which they will rise over the long term is unknown. Currently, the average rate of seawater rise is 1 foot per century, or twice the average rate of the 20th century. A moderate projection is five feet higher by 2100.
According to research from the Potsdam Institute for Climate Impact each degree Fahrenheit of global warming is equivalent to 4.2 feet of sea-level rise over the long term. This relationship means a 7 to 10 feet rise in sea levels by the end of this century. The shocking amount of water will cause equally shocking amounts of damage to coastal municpalities' infrastructure. Based on 2010 census data, 3.6 million Americans live in these municpalities: