As human-caused climate change warms the planet, ice loss has rapidly increased. A major UN climate report released this month concluded that the burning of fossil fuels led to Greenland melting over the past two decades. A recent study published in the journal Cryosphere found Earth has lost a staggering 28 trillion tonnes of ice since the mid-1990s, a large portion of which was from the Arctic, including the Greenland ice sheet.
In July, the Greenland ice sheet experienced one of the most significant melting events in the past decade, losing more than 8.5 billion tons of surface mass in a single day, which was enough to submerge Florida in two inches of water. It was the third instance of extreme melting in the past decade, during which time the melting has stretched farther inland than the entire satellite era, which began in the 1970s.
In 2019, Greenland shed roughly 532 billion tons of ice into the sea. During that year, an unexpectedly hot spring and a July heat wave caused almost the entire ice sheet’s surface to begin melting. Global sea level rose permanently by 1.5 millimeters as a result.

“We are crossing thresholds not seen in millennia, and frankly this is not going to change until we adjust what we’re doing to the air,” said Scambos.
Other unusual events have become more frequent, too, Mercer said.
Two years ago, a polar bear made it to the Summit Station, which was unusual since polar bears live in coastal regions where they can easily find food. The bear had trekked several hundred miles inland across the ice sheet. In the last five years, Mercer said three polar bears have been sighted high on Greenland’s ice sheet.

According to Mercer, the rain will have a lasting effect on the properties of the snow, leaving a crust of ice behind that will absorb more energy from the sun, until it gets buried by snow. Scambos said this crusty layer will also be a barrier that prevents the downward draining of melt water, which will then flood the surface of the ice sheet and initiate run off at higher elevations.
Because of the layer of ice it created, the weekend’s rainfall event “will be visible in ice core records in the future,” Mercer said.