Proceedings of the National Academy of Sciences, PNAS (December 22, 2009),Vol. 106, No. 51, pp. 21461-21462.
Projections of future sea level becoming more dire
Jonathan T. Overpeck* and Jeremy L. Weiss
University of Arizona, Tucson, AZ, U.S.A.
University of Arizona, Tucson, AZ, U.S.A.
Few of the possible impacts of future climate change have captured more public attention than sea-level rise. Globally, sea-level rise has accelerated since the 19th century, driven primarily by the expansion of warmer oceans and melting glaciers, along with a modest transfer of water into the ocean from the Earth's polar ice sheets. The observed rate of sea-level rise has not been uniform around the globe because of regional factors, but there is no doubt that the average sea-level trend is upwards (1). Implications for the rates and magnitudes of future sea-level rise are less clear, and a new study in this issue of PNAS (2) provides useful insight into how sea level will change through this century and beyond.
There are two main types of sea-level information needed to inform the development of effective climate change policy. First are estimates of the sea-level rise expected in the relative near term, namely by the end of the century. Second are estimates of the sea-level rise that will occur further into the future over many centuries as ice sheets and oceans come into equilibrium with a warmer atmosphere.
The Fourth Assessment of the Intergovernmental Panel on Climate Change (IPCC) (1) was unable to provide a strong constraint on estimates of sea-level rise likely to occur by the end of this century. Their projection of 0.26- to 0.59-m sea-level rise by 2100 (under the business as usual A1FI greenhouse gas emissions scenario; ref. 1) represents a lower-bound estimate because it …
Link: http://www.pnas.org/content/106/51/21461.extract
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