Today, NOAA published a new technical memorandum that estimates global mean sea level rise over the next century based on a comprehensive synthesis of existing scientific literature. The report finds that there is very high confidence (greater than 90% chance) that global mean sea level will rise at least 8 inches (0.2 meters) and no more than 6.6 feet (2 meters) by 2100, depending upon uncertainties associated with ice sheet loss and ocean warming.

The actual amount of sea level change at any one region and location greatly varies in response to regional and local vertical land movement and ocean dynamics. The ranges of global mean sea level rise estimates detailed in this study will help decision makers prepare for and respond to a wide range of future sea level rise and coastal inundation.

Higher mean sea levels increase the frequency, magnitude, and duration of flooding associated with a given storm. Flooding has disproportionately high impacts in most coastal regions, particularly in flat, low-lying areas. In the U.S., over eight million people live in areas at risk to coastal flooding, and many of the nation’s assets related to military readiness, energy, commerce, and ecosystems are already located at or near the ocean.

The report provides a synthesis of the scientific literature on global sea level rise, and presents a set of four global mean scenarios to describe future conditions for the purpose of assessing potential vulnerabilities and impacts. It was authored by a panel of scientists from multiple federal agencies and academic institutions, and will be used to support the National Climate Assessment — a U.S. interagency report produced once every four years to summarize the science and impacts of climate change on the United States.

The report is available online at http://www.cpo.noaa.gov/reports/sealevel.