Climate Number: 2200 Cubic Miles
Glaciers have a mass balance. Glaciers lose mass by melting during the warm season (primarily the summer months) and gain mass by accumulating snow during the cold season (centered around the winter months). If a glacier accumulates more mass during the cold season than it loses during the warm season, it is said to have a positive mass balance. If it loses more mass than it gains, it is said to have a negative mass balance. Since 1960, it has become more common for glaciers to have negative mass balance years than positive mass balance years, leading to an overall global trend of glacial retreat. It is estimated that since 1960, the world’s glaciers (this does not include the ice sheets on Greenland and Antarctica) have lost about 2200 cubic miles of ice. Because melt water from these glaciers feeds the creeks and rivers that ultimately flow into the ocean, more glacier melt means higher sea levels. About one-third of the recent 3.1 mm average annual sea level rise is due to glacial melt.
For Comparison: An equivalent to 2200 cubic miles of volume is about 36 million Great Pyramids of Giza, or about six million Sears Towers.
Seasons: Winter, 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.
