Greenland's ice sheet melts at a record pace
An extreme summer melt sent billions of tonnes of water pouring into the ocean, raising alarm over sea-level rise.
Greenland's vast ice sheet experienced an extreme melt this summer, with billions of tonnes of ice turning to water and pouring into the ocean during a period of exceptional warmth, in an event that alarmed scientists monitoring the frozen island's contribution to global sea-level rise.
During the peak of the melt season, a heat wave that had earlier shattered records in Europe moved north over Greenland, driving surface melting across almost the entire ice sheet and sending enormous quantities of meltwater cascading into the sea in a matter of days.
The Greenland ice sheet holds enough frozen water to raise global sea levels by several metres were it to melt entirely, and while that would take a very long time, the pace of its current loss is a major and growing contributor to the rise in the oceans. Each summer of extreme melt adds to the concern.
Scientists use satellites and field measurements to track the ice sheet's health, and the trend is unmistakable: Greenland is losing ice at an accelerating rate as the Arctic warms far faster than the global average.
The implications reach far beyond the Arctic, as rising seas threaten coastal cities and communities around the world. The record melt was a vivid reminder that changes unfolding in the remote polar regions have consequences for everyone, and that the great ice sheets, long thought stable, are responding to a warming world faster than once believed possible.