Tad Pfeffer presented "Disappearing Glacial Ice: A Global Synthesis" at the national American Geophysical Union (AGU) meeting, based on his work with fellow INSTAARs Mark Meier, Mark Dyurgerov, Robert Anderson, Suzanne Anderson, Shad O'Neel and Ursula Rick. Their study was based on the several hundred thousand small glaciers and small, pancake-shaped ice masses known as ice caps spread around the world in polar and temperate regions. Because of the challenge in inventorying each individual glacier, the researchers used a mathematical "scaling" process to estimate and characterize more remote glacier volumes, thicknesses and trends by factoring in data like altitude, climate and geography. Their research shows that small glaciers and ice caps have been contributing more to rising sea levels in recent years than the large Greenland and Antarctic ice sheets. In total, the small glaciers and ice caps are shedding about 400 billion tons of ice yearly -- nearly equal to the volume of Lake Erie. Earth's sea level currently is rising at about 3 millimeters per year and could rise by several feet or more by the end of the century if warming on Earth continues, according to recent studies.