“Hair-raising” study finds glaciers are melting at an accelerating rate
Stephen Leahy
Thursday, April 29th 2021, 1:55 pm - Water shortages in Canada and many other parts of the world are possible as glaciers rapidly recede.
The world’s glaciers are in an accelerating melt down according to the first ever study of all 220,000 glaciers. In the past two decades these mountain glaciers have lost an average of 267 billions tons of ice per year. That’s enough to submerge all of southern Ontario from Windsor to Cornwall and up to Algonquin Park under two meters of water every year.
This does not include ice loss from the Greenland and Antarctic ice sheets.
The Mendenhall Glacier in Juneau, Alaska is pictured here in February 2021. The glacier is one of many worldwide which are retreating. (Becky Bohrer/AP/via The Canadian Press)
Glacier mass is decreasing worldwide with an average total loss of 267 billion tonnes of mass per year, says a new study.
The period looked at was between 2000 and 2019. The loss of glacier mass during this period also accounted for 21 per cent of the observed sea-level rise, the authors said.
The study, “Accelerated global glacier mass loss in the early twenty-first century” was published in the journal
Nature on Wednesday.
Glacier mass loss has been accelerating by about 50 billion tonnes annually each decade since 2000, the study found.
“Processing spaceborne digital imagery to measure changes in surface elevation requires enormous computation power,” said UNBC professor and Hakai affiliate Dr. Brian Menounos, the Canada Research Chair in Glacier Change. “We needed an equivalent of about 584 modern computers running for about a year to derive these elevation models. Looked at another way, the generation of the elevation models required over five million compute hours.” The computations are part of a paper published in the April 29 issue of Nature that found that between 2000 and 2004, glaciers lost 227 gigatonnes of ice per year, but between 2015 and 2019, this rate increased to 298 gigatonnes per year. A gigatonne is equivalent to one billion tonnes. Loss of water from glaciers represents about 21 percent of the observed rise in sea levels over the last 20 years – some 0.74 millimetres a year.
CFNR Network
Apr 28, 2021 | 12:38 PM
A supercomputer at the University of Northern British Columbia has helped an international team of researchers discover that the rate of mass loss from Earth’s glaciers is accelerating.
The computer, which is jointly funded by UNBC and the Hakai Institute constructed digital elevation models based on more than 440,000 satellite images.
The computations are part of a paper publish in the April 29 issue of Nature that found between 2000 and 2004 glaciers lost 227 gigatonnes of ice per year, then in 2015 and 2019 that rate increased to 298 gigatonnes. A gigatonne is equivalent to one billion tonnes.
Researchers, led by ETH Zurich and University of Toulouse doctoral student Romain Hugonnet, measured elevation change from all of Earth’s glaciers.
The Dance Centre will showcase online performances in the lead up to International Dance Day on April 29.
The array of high-tech tools included aerial drones, electronic fish finders and data loggers equipped with satellite telemetry, a gyroscope, hydrophone and an underwater camera. Attached to the killer whales with suction cups, these devices allowed the scientists to record what the whales see and hear, as well as their movements in the water, and their diving and hunting behaviour.
The video clips, collected from above and below the water, samples of which can be viewed here were arresting. Some of the images took our breath away, says team leader Andrew Trites, a professor at the Institute for the Oceans and Fisheries Department of Zoology and the director of the Marine Mammal Research Unit at UBC. “It was amazing to watch the whales rolling through the water and moving in three-dimensions.”