Saturday, June 15

Rain concerns the Arctic, with a waterfall of uncomfortable modifications

This story was initially released by Yale Environment 360 and is recreated here as part of the Climate Desk cooperation.

In August 2021, rain fell atop the 10,551-foot top of the Greenland ice cap, activating an impressive crisis and a more than 2,000-foot retreat of the snow line. The extraordinary occasion advised Joel Harper, a University of Montana glaciologist who deals with the Greenland ice sheet, of an unusual abnormality in his information, one that recommended that in 2008 it may have drizzled much later on in the season– in the fall, when the area is generally in deep freeze and dark for practically 24 hours a day.

When Harper and his coworkers carefully analyzed the measurements they ‘d gathered from sensing units on the ice sheet those several years earlier, they were amazed. Not just had it drizzled, however it had actually drizzled for 4 days as the air temperature level increased by 30 degrees Celsius (54 degrees Fahrenheit), near and above the freezing point. It had actually warmed the top’s firn layer– snow that remains in shift to ending up being ice– by in between 11 and 42 degrees F (6 and 23 degrees C). The rainwater and surface area melt that followed permeated the firn by as much as 20 feet before refreezing, developing a barrier that would modify the circulation of meltwater the list below year.

All that rain is substantial due to the fact that the melting of the Greenland ice sheet– like the melting of other glaciers all over the world– is among the most crucial chauffeurs of water level increase. Each time a rain-on-snow occasion takes place, states Harper, the structure of the firn layer is changed, and it ends up being a bit more prone to effects from the next melting occasion. “It recommends that just a small boost in frequency and strength of comparable rain-on-snow occasions in the future will have an outsized effect,” he states.

Rain utilized to be uncommon in many parts of the Arctic: The polar areas were, and still are, typically too cold and dry for clouds to form and take in wetness. When rainfall did take place, it frequently came as snow.

Twenty years back, yearly rainfall in the Arctic varied from about 10 inches in southern locations to as couple of as 2 inches or less in the far north. As Arctic temperature levels continue to warm 3 times faster than the world as an entire, melting sea ice and more open water will, according to a current research study, bring up to 60 percent more rainfall in coming years, with more rain falling than snow in numerous locations.


Such modifications will have an extensive influence on sea ice, glaciers, and Greenland’s ice cap– which are currently melting at record rates, according to Mark Serreze, director of the National Snow and Ice Data Center at the University of Colorado. The rainfall will activate more flooding; a velocity in permafrost thaw; extensive modifications to water quality; more landslides and snow avalanches;

ยป …
Find out more