The Norwegian Svalbard Islands are located just few hundred miles from the North Pole. It is a unique environment for glaciers: Here glaciers can survive almost at sea level. This means that ice is constantly brushed by thick low-altitude air, which also dumps increasinlgy rain instead of snow.
As a result of high ocean temperatures and of precipitation nowadays falling as rain for months, the melting of these glaciers now occurs 25 times faster than just some years ago.
This also spells bad news for Northern Greenland's low lying glaciers, which will face increasing summertime flash floods as the Arctic Ocean becomes ice free and warms up, and as precipitation falls in the form of rain, rather than snow.
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| Sea surface temperature of 17.5°C, west of Svalbard click on image to enlarge |
Flash floods falling on glacier soften the compacted snow very rapidly to honeycombed ice that is exceedingly watery and without any internal strength.
Such ice can collapse simply under its own weight and the pulverised watery ice in the basin forms a near frictionless layer of debris.
Darkening of the melting ice also hastens its warming and melting.
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| Aggressively honeycombed glacier ice floating on meltwater lake in nearby Iceland. Image credit: Runólfur Hauksson |
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I suspect that climatically-speaking we are currently entering a methane-driven Bøllinger warming state with the Northern Cryosphere now entering a phase of rapid warming and melting of anything frozen (snow, sea ice, permafrost and sea bed methane clathrates).
This will be rapidly followed by a Heindrich Iceberg Calving event when the warmed and wet ice sheet in Greenland gives away to its increased weight (due to excessive melt water accumulation within and beneath the ice sheet).
This dislodges the ice sheet’s top, due to accumulation of “rotten ice” (honeycombed, soft ice with zero internal strength) at the ice sheet’s base and perimeters.
A huge melt water pulse to the ocean ensues with Jōkullhaups and ice debris loading the ocean with vast amounts of cold fresh water.
Within weeks an immense climatological reversal then occurs as the ocean gets loaded up with ice debris and cold water leading to the Last Dryas cooling and to world-wide droughts.
This loading of the ocean with ice and water leads to severe climatic flop, as the ocean and atmosphere cool rapidly and as falling salinity and sea water temperature briefly reverse all of the current Bøllinger warming, until the climatic forcing of the greenhouse gases again takes over the process, in turn leading to a new melt water pulse as another ice sheet or shelf disintegrates by the next warming.
Today’s rapid melt water lake formation in Greenland and the ultra-fast melting of glaciers are suggestive of near imminent deglaciation process in the Arctic.
Germany’s and Japan’s recent decisions to remove all their nuclear reactors from the sea sides may prove their worth sooner than many think in the far more conservative US and UK where “glacial speed” still means “eons of time”. Good luck UK/US!
I think cold 'Dryases' are not real Ice Ages, but hiatuses in a progressive melting process which results from changes in sea water salinity and temperature due to increases of meltwater and ice debris runoff from continental snow and ice that melt. As ocean gets less saline and colder the sea ice and snow cover temporarily grows.
But in the long run the greenhouse gas forcing and ocean wins and the warmth and melting resumes until the next big collapse of ice shelf and/or ice sheet. Hence there are meltwater pulses (such as 1a, 1b, 1c) and Heindrich Ice Berg Calving surges (2, 1, 0 - the last one being also called "Younger Dryas" as the Arctic Dryas octopetala grew in South once again after Ice Ages).
The next cooling from collapse of Greenland ice dome would be Heindrich Minus One as the zero has already been allocated to Younger Dryas ice berg surge. Here is an article worth reading on this risk. In Antarctica we see currently (already) a sea ice growth hiatus driven by increased runoff of melt water and ice debris from the continent and its surrounding ice shelves that are rapidly disintegrating.
This will be rapidly followed by a Heindrich Iceberg Calving event when the warmed and wet ice sheet in Greenland gives away to its increased weight (due to excessive melt water accumulation within and beneath the ice sheet).
This dislodges the ice sheet’s top, due to accumulation of “rotten ice” (honeycombed, soft ice with zero internal strength) at the ice sheet’s base and perimeters.
A huge melt water pulse to the ocean ensues with Jōkullhaups and ice debris loading the ocean with vast amounts of cold fresh water.
Within weeks an immense climatological reversal then occurs as the ocean gets loaded up with ice debris and cold water leading to the Last Dryas cooling and to world-wide droughts.
This loading of the ocean with ice and water leads to severe climatic flop, as the ocean and atmosphere cool rapidly and as falling salinity and sea water temperature briefly reverse all of the current Bøllinger warming, until the climatic forcing of the greenhouse gases again takes over the process, in turn leading to a new melt water pulse as another ice sheet or shelf disintegrates by the next warming.
Today’s rapid melt water lake formation in Greenland and the ultra-fast melting of glaciers are suggestive of near imminent deglaciation process in the Arctic.
Germany’s and Japan’s recent decisions to remove all their nuclear reactors from the sea sides may prove their worth sooner than many think in the far more conservative US and UK where “glacial speed” still means “eons of time”. Good luck UK/US!
I think cold 'Dryases' are not real Ice Ages, but hiatuses in a progressive melting process which results from changes in sea water salinity and temperature due to increases of meltwater and ice debris runoff from continental snow and ice that melt. As ocean gets less saline and colder the sea ice and snow cover temporarily grows.
But in the long run the greenhouse gas forcing and ocean wins and the warmth and melting resumes until the next big collapse of ice shelf and/or ice sheet. Hence there are meltwater pulses (such as 1a, 1b, 1c) and Heindrich Ice Berg Calving surges (2, 1, 0 - the last one being also called "Younger Dryas" as the Arctic Dryas octopetala grew in South once again after Ice Ages).
The next cooling from collapse of Greenland ice dome would be Heindrich Minus One as the zero has already been allocated to Younger Dryas ice berg surge. Here is an article worth reading on this risk. In Antarctica we see currently (already) a sea ice growth hiatus driven by increased runoff of melt water and ice debris from the continent and its surrounding ice shelves that are rapidly disintegrating.
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Post by Sam Carana.
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