And the effects, according to an international team, are equally clear—sea levels are rising faster than predicted, which could bring about disastrous effects for people and wildlife.

Rising seas would increase the risk of catastrophic flooding like that caused by Hurricane Sandy last month in New York and New Jersey. Environmental damage may include widespread erosion, contamination of aquifers and crops, and harm to marine life. And in the long term, rising seas may force hundreds of millions of people who live along the coast to abandon their homes.

By reconciling nearly two decades of often conflicting satellite data into one format—in other words, comparing apples to apples—the new study, published in the journal Science, made a more confident estimate of what's called ice sheet mass balance.

That refers to how much snow is deposited on an ice sheet versus how much is lost, either due to surface melting or ice breaking off glaciers.

Between 1992—when polar satellite measurements began—and 2011, the results show that all of the polar regions except for East Antarctica are losing ice, said study leader Andrew Shepherd, a professor of earth observation at the University of Leeds in the U.K.