Lubrication by meltwater may have enabled massive slide
Although the world’s ice and snow is melting rapidly on a geologic time scale, it still seems to be a gradual process, at least for casual observers. But last summer, July 16, to be exact, 70 million tons of ice broke off the Aru Glacier in western Tibet and crashed far down into the valley, killing nine nomadic yak herders. NASA scientists reported on the avalanche here.
A team of scientists who analyzed the giant avalanche now say there’s a good chance that global warming was a key factor in the unusual slide. The researchers, who published their findings this week in the Journal of Glaciology, said that that the avalanche lasted about four or five minutes, burying 3.7 square miles of the valley floor in that time. Something — likely meltwater at the base of the glacier — must have lubricated the ice to speed its flow down the mountain, they said. Continue reading “Study eyes link between giant Tibet avalanche and global warming”→
Arctic sea ice extent set a new record low this near, heightening concerns that the pace of the Arctic meltdown is speeding up. Antarctic sea ice extent also declined to a record low for the month, with sea ice cover worldwide dropping to an exceptionally low level, according the scientists at the National Snow and Ice Data Center.
Specifically, the blanket of ice around the North Pole averaged 3.51 million square miles for the month, the lowest November in the satellite record, and 309,000 square miles below the record set in November 2006. Through 2016, the linear rate of decline for November is 21,400 square miles per year, or 5.0 percent per decade. Continue reading “Global sea ice at record low in November”→
U.S. Geological Survey scientists have completed one of the first experimental studies to explore links between climate change and invasive species, specifically how brook trout and brown trout interact with rising stream temperatures. They found that non-native browns limit the ability of brook trout to use warmer water temperatures, By contrast, removin of browns brook trouts’ reach into warmer waters.
Scientists eye winter ecosystems in ice-covered lakes
A team of international scientists who studied more than 100 lakes during the winter said there’s more going on beneath the ice than we realized. Their findings stand to complicate the understanding of freshwater systems just as climate change is warming lakes around the planet, and shortening the ice season on many lakes. Other parts of the planet’s cryosphere are also melting under the thickening layer of heat-trapping greenhouse gas pollution.
“As ice seasons are getting shorter around the world, we are losing ice without a deep understanding of what we are losing,” said Stephanie Hampton, a Washington State University professor and lead author of a new study published in the journal Ecology Letters. “Food for fish, the chemical processes that affect their oxygen and greenhouse gas emissions will shift as ice recedes.” Continue reading “Life under the ice”→
Northern section hammered by warm ocean temperatures
Australian researchers this week released results of their latest Great Barrier Reef surveys, concluding that huge swaths of coral died in the past year under the onslaught of an ocean heatwave that led to widespread coral bleaching.
‘There is nowhere to go because they’re literally at the top of the continent … ‘
The findings of a new 20-year study suggest what already appeared obvious — that certain insects reliant on cold water from glaciers and snowmelt are endangered from global warming. The U.S. Geological Survey research focused on two stonefly species in Montana, and will be used to inform the status review for consideration of protection under the U.S. Endangered Species Act .