While the GRACE data alone do not say anything about the cause of Greenland's ice loss, the decrease does coincide with a warming climate and independent observations of increased glacier ice loss on the island.
"This leads us to think this [mass loss] is probably associated with ice discharge," Velicogna said.
Ice dischargethe dumping of glacial ice into the North Atlanticis a process with built-in inertia, Velicogna says.
Even if temperatures suddenly drop in Greenland, she says, the discharge would continue for several years.
Velicogna adds that if the mass loss is indeed associated with warming global temperatures and temperatures continue to rise, the accelerated melting could spread to northern Greenland.
"We don't know for sure, but it could happen and is something to be watched for," she said.
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