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View Full Version : Greenland’s ice cap has melted past ‘tipping point’



Maciamo
18-08-20, 09:14
Greenland’s ice cap has melted past ‘tipping point’ (https://www.brusselstimes.com/news/127163/greenlands-ice-cap-has-melted-past-tipping-point-scientists-claim/)

"The melting of the ice cap in Greenland is irremediable, scientists conclude in a new study (https://www.nature.com/articles/s43247-020-0001-2) published in the Communications Earth and Environment journal.

The ice cap would continue to shrink “even if global warming stopped today” because snowfall no longer compensates for the loss of ice.

“Greenland’s glaciers have passed a tipping point of sorts, where the snowfall that replenishes the ice sheet each year cannot keep up with the ice that is flowing into the ocean from glaciers,” said a statement from Ohio State University, where the authors of the study are working."

Here is the study in question:

Nature - Dynamic ice loss from the Greenland Ice Sheet driven by sustained glacier retreat (https://www.nature.com/articles/s43247-020-0001-2)

Abstract

The Greenland Ice Sheet is losing mass at accelerated rates in the 21st century, making it the largest single contributor to rising sea levels. Faster flow of outlet glaciers has substantially contributed to this loss, with the cause of speedup, and potential for future change, uncertain. Here we combine more than three decades of remotely sensed observational products of outlet glacier velocity, elevation, and front position changes over the full ice sheet. We compare decadal variability in discharge and calving front position and find that increased glacier discharge was due almost entirely to the retreat of glacier fronts, rather than inland ice sheet processes, with a remarkably consistent speedup of 4–5% per km of retreat across the ice sheet. We show that widespread retreat between 2000 and 2005 resulted in a step-increase in discharge and a switch to a new dynamic state of sustained mass loss that would persist even under a decline in surface melt.

Maciamo
26-08-20, 09:00
The Economist has also posted that The Greenland ice sheet has melted past the point of no return (https://www.economist.com/graphic-detail/2020/08/25/the-greenland-ice-sheet-has-melted-past-the-point-of-no-return). In other words, even if global warming stopped today, the Greenland ice sheet would keep shrinking and will eventually raise sea levels by more than seven metres.

https://www.economist.com/img/b/608/701/90/sites/default/files/20200829_WOC305.png

Andraste
28-08-20, 17:53
How sad, humans are destroying this once beautiful planet. I feel sorry for future generations. Too little is being done too late.

Dagne
29-08-20, 07:53
Somehow I think the planet will be just fine - it underwent many climatic changes. It is humans and firstly animals and plans who suffer from expanding human activity.
I wonder about actual meaning of meltdown to coastal territories...
In the Northern part of Lithuania coast erosion is very rapid, the Baltic sea - which is very much inland type of sea, not stormy, without tides, took about 60-70 meters of land during the last 70-80 years. The same thing in Northern Latvia, where a good storm may take about 25 meters of land on a one go.