Guwahati: Rain fell at the highest point on the Greenland ice sheet last week for the first time on record, another worrying sign of warming for the ice sheet already melting at an increasing rate, scientists said on August 20.
“That’s not a healthy sign for an ice sheet,” said Indrani Das, a glaciologist with Columbia University’s Lamont-Doherty Earth Observatory. “Water on ice is bad. … It makes the ice sheet more prone to surface melt.”
That meltwater is streaming into the ocean, causing sea levels to rise. Already, melting from Greenland’s ice sheet –the world’s second-largest after Antarctica’s — has caused around 25 percent of the global sea-level rise seen over the last few decades, scientists estimate. That share is expected to grow, as global temperatures increase.
The rain fell for several hours at the ice sheet’s 3,216-metre summit on Aug. 14, where temperatures remained above freezing for around nine hours, scientists at the US National Snow and Ice Data Center said.
Greenland experienced a massive melting event in late July when enough ice melted in a single day to cover the US state of Florida in 2 inches (5 cm) of water.
That melting event and last week’s rain were both caused by air circulation patterns which meant warm, moist air temporarily covered the island.
“This alarming rain at the summit of Greenland is not an isolated event,” said Twila Moon, deputy lead scientist with the US National Snow and Ice Data Center.
Along with rising floods, fires, and other extremes, it is one of many “alarm bells” signaling the need to reduce greenhouse gas emissions, she said.
“We really have to stay laser-focused on adapting, as well as reducing the potential for those to become truly devastating.”
