Greenland’s Growing “Ice Slabs” Intensify Meltwater Runoff into Ocean

Greenland’s Growing “Ice Slabs” Intensify Meltwater Runoff into Ocean

SOURCE: CIRES DATE: September 18, 2019 SNIP: Thick, impenetrable ice slabs are expanding rapidly on the interior of Greenland’s ice sheet, where the ice is normally porous and able to reabsorb meltwater. These slabs are instead sending meltwater spilling into the ocean, according to a new CIRES-led assessment, threatening to increase the country’s contribution to sea level rise by as much as 2.9 inches by 2100. Although runoff from ice slabs has added less than a millimeter to global sea levels so far, this contribution will grow substantially as ice slabs continue to expand in a warming climate, said Mike MacFerrin, a CIRES and University of Colorado Boulder researcher who led the new study, published today in Nature. “Even under moderate climate projections, ice slabs could double the size of the runoff zone by 2100,” MacFerrin said. “Under higher emissions scenarios, the runoff zone nearly triples in size.” “As the climate continues to warm, these ice slabs will continue to grow and enhance other meltwater feedbacks,” said Mahsa Moussavi, NSIDC researcher and a coauthor on the paper. “It’s a snowball effect: more melting creates more ice slabs, which create more melting, which, creates again more ice slabs.” This process fundamentally alters the ice sheet’s present and future hydrology. Arctic feedbacks like this are critical to understand because they show just how much, and how quickly, a warming climate can change Earth’s most vulnerable...
New Zealand glaciers won’t survive this century, scientists say

New Zealand glaciers won’t survive this century, scientists say

SOURCE: Stuff DATE: August 20, 2019 SNIP: Visitors to the Franz Josef glacier are noticing changes – it’s melting away and it’s not the only one. Victoria University of Wellington PHD Student Lauren Vargo said when surveys started in the late 1970s, New Zealand had more than 3000 glaciers. “From now on, we’ll see more disappear each year,” she said. “There are a couple that were quite decent sized glaciers when the surveys began, and they are essentially no longer glaciers and wouldn’t fit the definition of a glacier.” Most New Zealand glaciers have been rapidly declining since 2011. Both Franz Josef Glacier and Fox Glacier are no longer accessible by foot due to their retreat. Vargo said how long glaciers would survive climate change depended on their location and size. A recent and unpublished study has found New Zealand’s glacier areas reduced about 31 per cent from the late 1970s to 2016, Vargo said. This year it was found earth’s glaciers are melting much faster than scientists thought – five times faster now than they were in the 1960s. Niwa climate applications principal scientist Andrew Lorrey said if nothing changed globally, temperatures would continue to rise and the glaciers would continue to diminish. “Looking at these glaciers and how sensitive they are, I don’t see many of them surviving past the next century to be...
Alaska’s sea ice has completely melted away

Alaska’s sea ice has completely melted away

SOURCE: Mashable DATE: August 5, 2019 SNIP: Alaska’s exceptional summer continues. The most rapidly changing state in the U.S. has no sea ice within some 150 miles of its shores, according to high-resolution sea ice analysis from the National Weather Service. The big picture is clear: After an Arctic summer with well above-average temperatures, warmer seas, and a historic July heat wave, sea ice has vanished in Alaskan waters. “Alaska waters are ice free,” said Rick Thoman, a climate specialist at the Alaska Center for Climate Assessment and Policy. “This is definitely an extreme year — even by more recent standards in a changed Arctic,” noted Walt Walt Meier, a senior research scientist at the National Snow and Ice Data Center. Arctic sea ice has been either been at record lows or flirting with record lows throughout much of the summer. “I’m losing the ability to communicate the magnitude [of change],” Jeremy Mathis, a longtime Arctic researcher and current board director at the National Academies of Sciences, told Mashable in June, when sea ice levels were at their lowest point in the satellite record for that period. “I’m running out of adjectives to describe the scope of change we’re...
Europe’s record heat melted Swiss glaciers

Europe’s record heat melted Swiss glaciers

SOURCE: Science DATE: August 5, 2019 SNIP: The sweltering heat wave that roasted much of Europe last month has since moved north, where it’s wreaking havoc on the Greenland ice sheet. But while all eyes are currently trained on the Arctic ice, scientists are finding that Europe’s coldest places have also suffered. According to initial findings from the Swiss Glacier Monitoring Network (GLAMOS), Swiss glaciers experienced unusually high melt rates during the last heat wave, which occurred in late July, and an earlier heat wave that struck the continent in late June. Matthias Huss, a glaciologist with Swiss University ETH Zurich and head of GLAMOS, tweeted last week that the nation’s glaciers lost about 800 million metric tons of ice during the two heat waves alone. During the winter, the region received an above-average amount of snowfall, Huss pointed out. So the glaciers actually started the summer with a high level of snow cover and were doing “extraordinarily well” compared to the last few seasons, which have logged particularly strong losses, he noted. Scientists were hopeful that they’d end the season on a better note than the last few years. But once the first heat wave struck, the snow began to rapidly melt away. “Now, because of these two heat waves, we have tracked very fast downward,” Huss told E&E News. “And we are now at the average of the last 10 years, or even already a bit below.” Summers like this one, marked by extraordinary heat waves and high levels of melt, only exacerbate the problem. “Now we are really seeing almost every year another extreme year,” Huss...
Greenland Is Melting Away Before Our Eyes

Greenland Is Melting Away Before Our Eyes

SOURCE: Rolling Stone DATE: July 31, 2019 SNIP: Amid an ongoing heat wave, new data show the Greenland ice sheet is in the middle of its biggest melt season in recorded history. It’s the latest worrying signal climate change is accelerating far beyond the worst fears of even climate scientists. The record-setting heat wave that sweltered northern Europe last week has moved north over the critically vulnerable Greenland ice sheet, triggering temperatures this week that are as much as 25 to 30 degrees Fahrenheit warmer than normal. Weather models indicate Tuesday’s temperature may have surpassed 75 degrees Fahrenheit in some regions of Greenland, and a weather balloon launched near the capital Nuuk measured all-time record warmth just above the surface. That heat wave is still intensifying, and is expected to peak on Thursday with the biggest single-day melt ever recorded in Greenland. On August 1 alone, more than 12 billion tons of water will permanently melt away from the ice sheet and find its way down to the ocean, irreversibly raising sea levels globally. A tweet from the Danish Meteorological Institute, the official weather service of Greenland, said “almost all the ice sheet, including Summit” measurably melted on Tuesday. According to a preliminary estimate, that melt covered 87 percent of the ice sheet’s surface, which would be the second-biggest melt day in Greenland’s recorded history. Separate weather monitoring equipment at Summit Camp at the top of the 10,000-foot-thick Greenland ice sheet confirmed the temperature briefly reached the melting point. This week alone, Greenland will lose about 50 billion tons of ice, enough for a permanent rise in global sea...