Climate Fact: Glaciers and Sea Level
Increases in the sensible heat (heat that can be felt and measured with a thermometer) in Earth’s atmosphere translates into sea level rise in two ways: (a) the extra energy in the atmosphere is absorbed by the oceans, causing an expansion of the water and (b) the increase in atmospheric sensible heat is converted into latent heat as glaciers, ice caps and ice sheets melt. As ice melts, more water flows into the oceans. In the last 50 years, Earth’s ice cover has shrunk, meaning that there is now less ice on the planet than there was in the first half of the 20th century and more water molecules in the ocean. About 60 percent of these additional water molecules have come from glaciers/ice caps (excluding the Greenland and Antarctic ice sheets). Since 1960, about 2200 cubic miles of glacial ice has gone into the ocean. This glacial ice contributes about 1.1 mm per year to the overall 3.1 mm per year of sea level rise.
Seasons: Spring, Summer, Fall
Sources: Global Climate Change Impacts in the United States, Thomas R. Karl, Jerry M. Melillo, and Thomas C. Peterson,(eds.). Cambridge University Press, 2009 and Meier, MF et al. “Glaciers Dominate Eustatic Sea-Level Rise in the 21st Century.” Science Express 19 July 2007 / Page 1 / 10.1126/science.1143906.
