Scientists said Friday that the highest point of the Greenland ice sheet recorded rain last week for the first time in history, another worrying sign of the warming of the ice sheet that is already melting at an increasing rate.
“This is not a healthy sign for ice sheets,” said Indrani Das, a glaciologist at Columbia University’s Lamont-Doherty Earth Observatory. “The water on ice is bad…it makes the ice sheet more likely to melt.”
Water is not only warmer than regular snow, but it is also darker – so it absorbs more sunlight rather than reflecting it.
This molten water flows into the ocean, causing sea level to rise. Scientists estimate that melting Greenland’s ice sheet – the world’s second largest after Antarctica – has caused about 25% of global sea-level rise in recent decades. This share is expected to grow as global temperatures rise.
On August 14, scientists at the US National Snow and Ice Data Center said rain fell for several hours on top of the 3,216-meter-high ice sheet, with temperatures remaining above freezing for nine hours.
Rain and high temperatures caused widespread melting across the island, which experienced a loss of surface ice mass on August 15, seven times the average in mid-August.
