At the end of the last ice age, parts of an enormous ice sheet covering Eurasia retreated up to a startling 2,000 feet per day - more than the length of the Empire State Building, according to a study released Wednesday. The rate is easily the fastest measured to date, upending what scientists previously thought were the upper speed limits for ice sheet retreat - a finding that may shed light on how quickly ice in Greenland and Antarctica could melt and raise global sea levels in today's warming world.
Scientists monitor ice sheet retreat rates to better estimate contributions to global sea level rise. Antarctica and Greenland have lost more than 6.4 trillion tons of ice since the 1990s, boosting global sea levels by at least 0.7 inches (17.8 millimeters). Together, the two ice sheets are responsible for more than one-third of total sea level rise.