Why the Last Snow on Earth May Be Red

Why the Last Snow on Earth May Be Red

SOURCE: The New Yorker DATE: September 21, 2017 SNIP: Every spring, in alpine regions around the world, one of Earth’s tiniest migrations takes place. The migrants are single-celled green algae; they are kin to seaweed, but instead of living in the sea they live in snow. (Snow weed, maybe?) They spend the winter deep in the snowpack, atop last summer’s snow, as dormant cysts. In the spring, they wake and swim up through the trickle of snowmelt to the surface, dividing and photosynthesizing as they go. Then, at the top, they turn red. This creates what scientists call pink snow or watermelon snow—drifts and glaciers that look like Slush Puppies and eventually reduce to rivulets of crimson. Watermelon snow is a perfectly natural phenomenon, but in an age of disappearing glaciers it is also problematic. Last year, scientists discovered that the algae had reduced the amount of sunlight reflected by some glaciers in Scandinavia—and increased the amount of sunlight absorbed—by thirteen per cent. The result, as Dial and his colleagues demonstrated in this month’s issue of Nature Geoscience, is faster melting. As in other parts of the warming planet—particularly the Arctic, where scientists fear that thawing permafrost may be triggering a climatic feedback loop—the effect is likely self-perpetuating. Ice sheets are already being darkened by dust, soot, and ash, which hasten melting and add nutrients on which algae can flourish. As the organisms proliferate, they melt even more snow, which allows them to proliferate again. “It spreads more rapidly than people realize, once it gets established,” Dial...
As Arctic warms, Canada’s glaciers playing major role in sea level rise

As Arctic warms, Canada’s glaciers playing major role in sea level rise

SOURCE: CBC News DATE: February 20, 2017 SNIP: Canada’s glaciers are responding rapidly to a warming Arctic and are a major contributor to sea level rise, a new study suggests. Researchers from the University of California Irvine studied data collected from 1991 to 2015 on glaciers found in the Queen Elizabeth Islands in the Arctic. They found that, from 2005 to 2015, surface melt off of these glaciers rose by 900 per cent — something they say is attributable to warming air temperatures in the region. They have gone from shedding three gigatons of water annually to 30 gigatons — something that has serious...
Antarctic Bottom Waters Freshening at Unexpected Rate

Antarctic Bottom Waters Freshening at Unexpected Rate

SOURCE: Scripps Institution of Oceanography DATE: February 1, 2017 SNIP: In the cold depths along the seafloor, Antarctic Bottom Waters are part of a global circulatory system, supplying waters rich in oxygen, carbon, and nutrients to the world’s oceans. Over the last decade, scientists have been monitoring changes in these waters. But a new study from the Woods Hole Oceanographic Institution (WHOI) and Scripps Institution of Oceanography at the University of California San Diego suggests these changes are themselves shifting in unexpected ways with potentially significant consequences for the ocean and climate. In a paper published Jan. 25 in the journal Science Advances, a team led by WHOI oceanographers Viviane Menezes and Alison Macdonald and Scripps researcher Courtney Schatzman report that Antarctic Bottom Water (AABW) has freshened (become less saline) at a surprising rate between 2007 and 2016—a shift that could alter ocean circulation and ultimately contribute to rising sea levels. … AABW in the region off East Antarctica’s Adélie Land has grown fresher four times faster in the past decade than it did between 1994 and 2007. … Such a shift, were it global, could significantly disrupt ocean circulation and sea...
Greenland’s Ice Sheet Is Melting So Fast Right Now, Scientists Thought It Was an Error

Greenland’s Ice Sheet Is Melting So Fast Right Now, Scientists Thought It Was an Error

SOURCE: Slate DATE: Eric Holthaus AUTHOR: April 13, 2016 SNIP: On Monday, Greenland began to melt. Parts of Greenland melt every year and the whole thing freezes again each winter, but lately, thanks to global warming, the melting has come earlier and then peaked in the summer at higher levels than usual. Even in light of these trends, Monday’s melt was unlike anything the scientists studying Greenland have ever seen—it was so different, in fact, that they thought the data was wrong. … The implications of this sudden shift are still being worked out, but climate scientist James Hansen’s recent study provides a preview: We can look forward to faster sea level rise, stronger storms, and even a potential destabilization of global governance, should greenhouse gas emissions continue essentially unchecked. Of course, this week’s melt event in Greenland is just a single additional data point in this trove of evidence, but it’s a dramatic...
Clouds having a greater impact on Greenland than previously thought

Clouds having a greater impact on Greenland than previously thought

SOURCE: Accuweather.com DATE: January 13, 2016 SNIP: New research led by the University of Leuven (Belgium) and assisted by the University of Wisconsin-Madison indicates that cloud cover over the Greenland Ice Sheet is playing a larger role than previously thought by raising the temperature of the ice sheet some 2 to 3 degrees compared to days with no clouds. The above process is likely accounting for as much as 30 percent of the ice sheet melt, according to the University of Wisconsin News. The impact of this could be a global sea level rise of an additional foot over the next 80 years, according to co-author Tristan L’Ecuyer of the University of...