WASHINGTON, Aug. 26 (UPI) -- NASA's scientists say current sea level models don't sufficiently account for the potential destabilization of polar ice sheets. The future, they say, could be be worse than the worst-case scenarios.
Current models predict global sea levels to rise between one and three feet by the end of the century. But NASA scientists say new research suggests the upper end of that range is most probable. The range could shift even higher, as researchers learn more.
Sea level rise is influenced by the expansion of water molecules as they warm, ice sheet losses and the melting of mountain glaciers. The problem is researchers still don't fully understand the complexities of Earth's major ice sheets, in Greenland and Antarctica.
Both sheets have been shedding ice in recent years, and scientists are scrambling to see whether the current losses will precipitate more dramatic losses in the future.
"The prevailing view among specialists has been that East Antarctica is stable, but we don't really know," glaciologist Eric Rignot, a researcher at the University of California Irvine and NASA's Jet Propulsion Laboratory, said in a press release. "Some of the signs we see in the satellite data right now are red flags that these glaciers might not be as stable as we once thought. There's always a lot of attention on the changes we see now, but as scientists our priority needs to be on what the changes could be tomorrow."
NASA recently initiated a six-year field campaign to study the effects of warming waters and changing current patterns on the degradation of Greenland's ice sheet.
Until researchers know more, scientists say, more dramatic sea level rise shouldn't be ruled out.
"We've seen from the paleoclimate record that sea level rise of as much as 10 feet in a century or two is possible, if the ice sheets fall apart rapidly," said Tom Wagner, NASA's cryosphere program scientist. "We're seeing evidence that the ice sheets are waking up, but we need to understand them better before we can say we're in a new era of rapid ice loss."