SOURCE: Scientific American
DATE: June 3, 2020
SNIP: A significant melt event is unfolding in Greenland this week.
With temperatures nearly 20 degrees Fahrenheit higher than usual in some areas, the southern part of the ice sheet is melting at its highest rate this season. Forecasts suggest that the melting on Greenland’s South Dome—one of the highest elevations on the ice sheet—may be the strongest for early June since 1950.
It worries experts that Greenland could be priming for another big melt season.
Early melting this spring, low snowpack in some areas and the potential for strong high-pressure weather systems later this summer have all raised red flags. Scientists are paying close attention after last summer’s record-breaking ice loss—an event scientists expect to occur more frequently as the Arctic continues to warm.
Scientists typically define the beginning of melt season as the first three-day period in which melting is observed across at least 5% of the ice sheet. This year, that period began on May 13—nearly two weeks earlier on average over the last few decades.
The melting coincided with a heat wave across much of the Arctic. Siberia and the central Arctic were some of the hardest-hit regions. But temperatures skyrocketed in parts of Greenland, as well, after an otherwise chilly start to the month.
At the same time, snow began rapidly disappearing along the margins of the ice sheet, exposing bare rock and ice. The lack of snow is one factor increasing the possibility of an above-average melt year, according to Jason Box, an ice expert with the Geological Survey of Denmark and Greenland.
It’s possible that more heat waves are on the way.
According to Judah Cohen, director of seasonal forecasting at the analytics firm Atmospheric and Environmental Research, model forecasts suggest strong high-pressure events over Greenland this summer. High-pressure systems are often associated with warming on the ice sheet.