Glaciers Falling on Tourists: Yet Another Danger of Climate Change

Glaciers Falling on Tourists: Yet Another Danger of Climate Change

SOURCE: The Atlantic DATE: September 11, 2018 SNIP: In the summer of 1987, a woman visiting Alaska was crushed by a 1,000-pound chunk of ice. According to news reports at the time, Thais Grabenauer, 59, had been taking pictures with her husband at the foot of Exit Glacier, a towering wall of ice that’s one of the most popular attractions in Kenai Fjords National Park. A half-ton piece of the glacier calved off as the couple was snapping, killing Grabenauer and injuring her husband. It was one of those wrong place, wrong time tragedies that seem unlikely to happen again. But in the three decades since Grabenauer’s death, it has happened again—in Alaska and around the rest of the world. In 2009, for instance, two brothers crossed a safety barrier on New Zealand’s Fox Glacier and were buried under a collapsing ice shelf. On a single day last July, two people were killed at separate glaciers in south-central Alaska: A 32-year-old woman was crushed by a collapsing ice ceiling on Byron Glacier, and a 5-year-old boy was hit by a rock falling from Worthington Glacier. Deaths like these remain rare, but they’re also telling cases of a broader trend. In recent years, people have been increasingly flocking to the world’s glaciers. This boom in “glacier tourism” seems to be dually spurred, at least in part, by climate change: For one, people seem eager to glimpse the majestic monuments of ice before they melt away. And as ice sheets disappear, many glaciers are becoming more accessible—and unstable. The result is that places such as Exit Glacier are not only witnessing...
Antarctica’s Ice Loss Is Speeding Up, with Sharp Acceleration in Past 5 Years

Antarctica’s Ice Loss Is Speeding Up, with Sharp Acceleration in Past 5 Years

SOURCE: Inside Climate News and Nature DATE: June 13, 2018 SNIP: The most complete assessment to date of Antarctica’s ice sheets confirms that the meltdown accelerated sharply in the past five years, and there is no sign of a slowdown. That means sea level is expected to rise at a rate that will catch some coastal communities unprepared despite persistent warnings, according to the international team of scientists publishing a series of related studies this week in the journal Nature. The scientists found that the rate of ice loss over the past five years had tripled compared to the previous two decades, suggesting an additional 6 inches of sea level rise from Antarctica alone by 2100, on top of the 2 feet already projected from all sources, including Greenland. Between 1992, when detailed satellite measurements started, and 2012, Antarctica lost about 76 billion tons of ice per year. But since 2012, that rate has tripled to about 219 billion tons of ice loss per year, the scientists found. Another study, published June 13 in the journal Science Advances, raises even more concerns about the vulnerability of Antarctic ice to global warming. Data from radar and laser readings of the ice enabled scientists with the University of Texas at Austin and the University of Waterloo to map a vast network of channels in the base of many ice sheets formed by intrusions of warm water. Some are several kilometers wide, said University of Texas at Austin researcher Jamin Greenbaum. They found the channels everywhere they looked, including beneath the ice shelf of the Totten Glacier, in East Antarctica, as well...
Unprecedented U.S.-British project launches to study the world’s most dangerous glacier

Unprecedented U.S.-British project launches to study the world’s most dangerous glacier

SOURCE: The Washington Post DATE: April 30, 2018 SNIP: The largest U.S.-British Antarctic mission in seven decades officially launched at an event in Cambridge on Monday, as the two countries pooled dollars and scientific resources for missions to West Antarctica’s Thwaites glacier — a Florida-size ice body that, scientists fear, could flood the world’s coastlines in our lifetimes. “For global sea-level change in the next century, this Thwaites glacier is almost the entire story,” said David Holland, a geoscientist at New York University. Thwaites is wide and deep and flows out of the heart of West Antarctica, a marine ice sheet that could contribute about 10 feet of global sea-level rise. Thwaites is losing ice rapidly, with its 50 billion tons per year currently driving 4 percent of global sea-level rise, and sits perched in 2,600-foot-deep waters atop a seafloor “bump” that scientists fear is the last thing holding it in place. Thwaites is a key part of the reason that recent computer modeling studies have predicted that the Antarctic could double the previously projected rate of sea-level rise during this century. It’s among the most difficult places on Earth for humans to...
Sea levels could be rising faster than predicted due to new source of Antarctic ice melting

Sea levels could be rising faster than predicted due to new source of Antarctic ice melting

SOURCE: The Independent and Science Daily DATE: April 18, 2018 SNIP: Sea level rise could be happening at a faster rate than previously thought, as scientists have identified a new source of melting ice in Antarctica. Melting glaciers can create a positive feedback loop in which the more they melt, the more they drive further melting, according to the Australian team. They predict that the processes they identified could be playing a role in accelerating both sea level rise and climate change. As glaciers melt, they produce fresh water. When this meltwater enters the ocean surrounding the glacier it makes the surface layer less salty and therefore more buoyant. This leads to a layer of water floating on the surface, and prevents the natural mixing of the ocean. The lack of mixing becomes a problem during winter, as it prevents warm water at greater depths from mixing with cooler water above. With a pool of warm water underneath them, the melting of the bottom side of the glaciers...
Underwater melting of Antarctic ice far greater than thought, study finds

Underwater melting of Antarctic ice far greater than thought, study finds

SOURCE: The Guardian DATE: April 2, 2018 SNIP: Hidden underwater melt-off in the Antarctic is doubling every 20 years and could soon overtake Greenland to become the biggest source of sea-level rise, according to the first complete underwater map of the world’s largest body of ice. Warming waters have caused the base of ice near the ocean floor around the south pole to shrink by 1,463 square kilometres – an area the size of Greater London – between 2010 and 2016. The research by the UK Centre for Polar Observation and Modelling at the University of Leeds suggests climate change is affecting the Antarctic more than previously believed and is likely to prompt global projections of sea-level rise to be revised upward. “What’s happening is that Antarctica is being melted away at its base. We can’t see it, because it’s happening below the sea surface,” said Professor Andrew Shepherd, one of the authors of the paper. “The changes mean that very soon the sea-level contribution from Antarctica could outstrip that from...