Climate change is expanding Antarctica's sea ice, according to a scientific study in the journal Nature Geoscience.

The paradoxical phenomenon is thought to be caused by relatively cold plumes of fresh water derived from melting beneath the Antarctic ice shelves.

This melt water has a relatively low density, so it accumulates in the top layer of the ocean.

The cool surface waters then re-freeze more easily during Autumn and Winter.

This explains the observed peak in sea ice during these seasons, a team from the Royal Netherlands Meteorological Institute (KNMI) in De Bilt says in its peer-reviewed paper.

Climate scientists have been intrigued by observations that Antarctic sea ice shows a small but statistically significant expansion of about 1.9% per decade since 1985, while sea ice in the Arctic has been shrinking over past decades.

The researchers from the KNMI suggest the "negative feedback" effect outlined in their study is expected to continue into the future.

They tried to reproduce the observed changes in a computer-based climate model.

The sea ice expanded during Southern Hemisphere autumn and winter in response to the development of this fresh, cool surface layer, which floated on the denser, warmer salty sea water below.

http://www.bbc.co.uk/news/science-environment-21991487

A report has found that the Antarctic summer ice melt is now occurring 10 times faster than it did 600 years ago.

Scientists from the British Antarctic Survey and the Australian National University drilled a 360-metre ice core near the northern tip of the peninsula to to identify past temperatures.

The ice core gave an extraordinary insight into the temperatures, revealing the coolest conditions, and the lowest melt, occurred six centuries ago.

By comparison, it found temperatures now are 1.6 degrees Celsius higher, and the ice melt is 10 times as fast.

The lead author of the report, Dr Nerilie Abram from the Australian National University, says the most rapid melt has occurred in the last 50 years.

"The lowest levels of melt were about 600 years ago and then the melt has increased almost tenfold over that time," she said.

"But it's really in the last 50 years or so that melt has increased dramatically.

http://www.abc.net.au/news/2013-04-15/antarctic-melting-ten-times-faster-than-600-years-ago/4628404

The melting of Antarctic and Greenland ice sheets is accelerating and may trigger faster sea level rise than predicted, according to leaked details of the forthcoming Intergovernmental Panel on Climate Change report.
Greenland's ice added six times more to sea levels in the decade through 2011 than in the prior 10 years, according to details of a draft 2200-page study by the UN agency, obtained by Bloomberg.
The Antarctic experienced a five-fold increase, prompting the UN to raise its forecast for how much the two ice sheets would add to Earth's oceans by 2100.The leak comes just weeks before the IPCC gathers on September 23 in Stockholm, with the Fifth Assessment Report scheduled to be released four days later. National delegates are expected to wade through 1800 comments to achieve consensus on the important Summary for Policymakers during the event.

The report's assessment of ice melt from Greenland and Antarctica will be closely watched. The previous IPCC report, released in 2007, drew criticism from some scientists for underplaying the potential contribution from the two regions.
"Greenland is losing mass and the rate of loss from Greenland has increased," said Ian Allison, a Hobart-based honorary research professor and lead author of the IPCC report's chapter on the cryosphere. "Antarctica is also losing mass but the signal is not so strong whether it's accelerating."
Sea levels are now forecast to rise by as much as 80 centimetres by the end of the century and are expected to continue to rise after that.


Read more: http://www.smh.com.au/environment/seas-may-be-rising-faster-than-predicted-scientists-20130906-2tanz.html#ixzz2eHYOoRLX

Read article at top...

The last edge of the Greenland ice sheet that resisted global warming has now become unstable, adding billions of tonnes of meltwater to rising seas, scientists have said.

In a study published in the journal Nature Climate Change, researchers said a surge in temperature from 2003 had eased the brakes on a long "river" of ice that flows to the coast in north-eastern Greenland.

Known as an ice stream, the "river" takes ice from a vast basin and slowly shifts it to the sea - in the same way that the Amazon River drains water.

In the past, the flow from this ice stream had been constrained by massive build-ups of ice debris choking its mouth.

But a three-year spell of exceptionally high temperatures removed this blockage and, like a cork removed from a bottle, helped accelerate the flow, the study said.

The ice stream, called Zachariae, is the largest drain from an ice basin that covers a whopping 16 per cent of the Greenland ice sheet.

From 2003 to 2012, north-eastern Greenland disgorged 10 billion tonnes of ice annually into the ocean, the study found.

"North-east Greenland is very cold. It used to be considered the last stable part of the Greenland ice sheet," said Michael Bevis, an Earth sciences professor at Ohio State University, who led the study.

"This study shows that ice loss in the north-east is now accelerating. So, now it seems that all the margins of the Greenland ice sheet are unstable."

Greenland is estimated to contribute 0.5mm to the 3.2mm annual rise in global sea levels.

The main tool in the study was data from a network of 50 Global Positioning System (GPS) sensors along the Greenland coast.

The monitors use Earth's natural elasticity as a stethoscope of the ice sheet.

Ice is heavy, so when it melts in massive quantities the land rebounds and the position of the sensors changes slightly.

To get a wider picture, the GPS data was then overlaid with data from three US satellites and a European one that measured ice thickness from space.

"The Greenland ice sheet has contributed more than any other ice mass to sea level rise over the last two decades and has the potential, if it were completely melted, to raise global sea level by more than seven metres," said Jonathan Bamber, a professor at Britain's University of Bristol.

"About half of the increased contribution of the ice sheet is due to the speed-up of glaciers in the south and north-west. Until recently, north-east Greenland has been relatively stable. This new study shows that it is no longer the case."

http://www.abc.net.au/news/2014-03-17/global-warming-melts-greenland-ice-sheet/5324848

---------------------------

Meanwhile at the CSIRO (being decimated with savage staff cuts which Tony the non-scientific Turd-in-Chief is letting fester:

A new study on the impacts of climate change shows warming will lead to heavier losses in global crop yields than previously believed.

The study compiled by researchers from Australia, Colombia, the United States and the United Kingdom looks at global crop yields under projected levels of climate change.

Co-author Mark Howden from the CSIRO says it shows wheat, maize and rice crop yields decline by around 5 per cent for every degree of warming.

"Reductions in yields tended to increase as the temperature went up and up," he said.

Yields also go down more rapidly in tropical environments than they do in temperate environments, the study says.

Dr Howden says the result is worse than previous forecasts.

"Looking back a few years we thought maybe we could get away with a bit more warming before we went negative, but this is actually showing the spike will happen sooner than later," he said.

Dr Howden says the agriculture sector will need to adapt to avoid global food shortages.

"There's a lot of things you can do like management changes, changes in varieties and potentially changes in location as well," he said.

The study will be published in the journal Nature Climate Change.

http://www.abc.net.au/news/2014-03-17/climate-change-effect-on-crops-worse-than-thought-study/5325130

Read article at top. Meanwhile there are many mining companies who can hardly wait for the Greenland "defrost"... 

Part of East Antarctica is more vulnerable than expected to a thaw that could trigger an unstoppable slide of ice into the ocean and raise world sea levels for thousands of years, a new study showed.

The Wilkes Basin in East Antarctica, stretching more than 1,000 km inland, has enough ice to raise sea levels by 3 to 4 metres if it were to melt as an effect of global warming, the report said.

The Wilkes is vulnerable because it is held in place by a small rim of ice, resting on bedrock below sea level by the coast of the frozen continent. That "ice plug" might melt away in coming centuries if ocean waters warm up.

"East Antarctica's Wilkes Basin is like a bottle on a slant. Once uncorked, it empties out," Matthias Mengel of the Potsdam Institute for Climate Impact Research, lead author of the study in the journal Nature Climate Change, said in a statement.

Co-author Anders Levermann, also at Potsdam in Germany, told Reuters the main finding was that the ice flow would be irreversible, if set in motion. He said there was still time to limit warming to levels to keep the ice plug in place.

Almost 200 governments have promised to work out a U.N. deal by the end of 2015 to curb increasing emissions of man-made greenhouse gases that a U.N. panel says will cause more droughts, heatwaves, downpours and rising sea levels.

Worries about rising seas that could swamp low-lying areas from Shanghai to Florida focus most on ice in Greenland and West Antarctica, as well as far smaller amounts of ice in mountain ranges from the Himalayas to the Andes.

The report shows that between 1300 and 1400AD there was a significant weakening of the winds, but Dr Abram said this recent strengthening was more than natural variability.

"That's why having these long records [is so important]," she said.

"We can see that what's happening now steps outside that envelope of natural variability and is something that's unusual.

"We can then relate that quite clearly to the increases in greenhouse gases in the atmosphere."

Sceptics have pointed to the fact that Antarctica is not warming as fast as the rest of the world, as an example of the climate change threat being overblown.

Dr Abram said her work questioned some of those theories.

"We can explain Antarctica not getting warmer as quickly as the other continents by the strengthening of the westerly winds," she said.

"Because as those westerly winds tighten around Antarctica, they actually trap air and they stop those warm winds from being able to come in over the continent."

Since the 1970s, Antarctic sea ice has on the whole has actually been increasing - adding 285,000 square kilometres every decade according to the Antarctic Climate and Ecosystems Cooperative Research Centre.

Sceptics say that is another reason why warming is not as bad as first thought, but University of New South Wales Professor Matthew England does not agree with that argument.

"I wish they were right because it would leave one part of the climate system relatively untouched from global warming, but unfortunately they're wrong," he said."They're avoiding looking at the data of the West Antarctic Ice Sheet which shows rapid warming, a loss of ice and a contribution to sea level that is accelerating.

"Of course, even if the whole of Antarctica was staying resilient and cold and there was no ice lost from that part of the world, the fact is the Greenland ice sheet is melting rapidly and that doesn't just leave sea levels rising in the north Atlantic.

read more: http://www.abc.net.au/news/2014-05-12/scientists-have-new-explanation-for-drying-australia/5445134

Last Monday, we hosted a Nasa conference on the state of the West Antarctic ice sheet, which, it could be said, provoked something of a reaction. "This Is What a Holy Shit Moment for Global Warming Looks Like," ran a headline in Mother Jones magazine.

We announced that we had collected enough observations to conclude that the retreat of ice in the Amundsen sea sector of West Antarctica was unstoppable, with major consequences – it will mean that sea levels will rise one metre worldwide. What's more, its disappearance will likely trigger the collapse of the rest of the West Antarctic ice sheet, which comes with a sea level rise of between three and five metres. Such an event will displace millions of people worldwide.

Two centuries – if that is what it takes – may seem like a long time, but there is no red button to stop this process. Reversing the climate system to what it was in the 1970s seems unlikely; we can barely get a grip on emissions that have tripled since the Kyoto protocol, which was designed to hit reduction targets. Slowing down climate warming remains a good idea, however – the Antarctic system will at least take longer to get to this point.

The Amundsen sea sector is almost as big as France. Six glaciers drain it. The two largest ones are Pine Island glacier (30km wide) and Thwaites glacier (100km wide). They stretch over 500km.

Many impressive scientists have gone before us in this territory. The concept of West Antarctic instability goes back to the 1970s following surveys by Charles Bentley in the 1960s that revealed an ice sheet resting on a bed grounded well below sea level and deepening inland. Hans Weertman had shown in 1974 that a marine-based ice sheet resting on a retrograde bed was unstable. Robert Thomas extended his work to pursue the instability hypothesis. Terry Hughes suggested that the Pine Island sector of West Antarctica was its weak underbelly and that its retreat would collapse the West Antarctic ice sheet. Considerable uncertainty remained about the timescale, however, due to a lack of observation of this very remote area.

http://www.theguardian.com/commentisfree/2014/may/17/climate-change-antarctica-glaciers-melting-global-warming-nasa

Global warming is real and anthropomorphic...

This is where proper sciences and Gus' farting around come together... Read my unscientific article at top explaining the way ice can increase while temperature increases... It's not fancy footwork but personal observation that has stayed with me since the 1940s... 

And now as increasing wind swirls around Antarctica here are more observations:

NARRATION 
They call it Antarctica's paradox. As the coldest continent in the world warms up, its surrounding sea ice zone is expanding instead of shrinking. It's given rise to the idea that Antarctica is immune to global warming. Some even say it's foolish to research climate change in this icy behemoth. But appearances can be deceiving, and to treat Antarctica with disregard may well be the most foolish move of them all.

Anja Taylor 
You need a lot of gear to stay warm in east Antarctica, but I'm just going to stand in a freezer for a couple of hours. It's the closest I'll get to a place called Law Dome, a place where you can travel far back in time.

NARRATION 
With no ocean in sight, it seems a strange place to solve mysteries about sea ice. But that's exactly what Dr Mark Curran is doing.

Dr Mark Curran 
It snows a lot at Law Dome, which is great when you want to drill an ice core to get a climate history. It gives a very detailed climate history.

NARRATION 
The deeper the drill, the older the ice, and cores from here go back tens of thousands of years. Mark's interested in the top of the core, the last couple of centuries. This small piece is just one month of snowfall and it contains all sorts of treasures.

Dr Mark Curran 
So typically we can look at things like oxygen isotopes, so we can get temperature records from that. We can look at the carbon dioxide in the bubbles, so we can get carbon dioxide concentrates. And also we can look for sulphate in there, which gives us a measure of the large volcanos that happened in the past.

Anja Taylor 
But that's not what you're looking at in the ice core, is it?

Dr Mark Curran 
No. I'm looking at a compound called methanesulfonic acid or MSA. And MSA is produced from algae in the ocean.

NARRATION 
Algae in surface waters do well when there's sea ice around. The chemical they produce is carried in water vapour from the ocean and later falls as snow on the continent.

Read more: http://www.abc.net.au/catalyst/stories/4056545.htm

The oh-shit moment could come as soon as this coming southern hemisphere summer, 2014. They call it the Antarctica paradox. I call it the Antarctica conundrum.

Global warming is real and anthropomorphic...

Antarctic scientists have declared a new record has been set for the extent of Antarctic sea ice since records began.

Satellite imagery reveals an area of about 20 million square kilometres covered by sea ice around the Antarctic continent.

Jan Lieser from the Antarctic Climate and Ecosystems CRC said the discovery was made two days ago.

"This is an area covered by sea ice which we've never seen from space before," he said.

"Thirty-five years ago the first satellites went up which were reliably telling us what area, two dimensional area, of sea ice was covered and we've never seen that before, that much area.

"That is roughly double the size of the Antarctic continent and about three times, four times the size of Australia."

The formation of sea ice around Antarctica every year is one of the biggest seasonal events on Earth.

The ice is generated in what scientists refer to as "sea ice factories" or polynias; areas of the ocean surface where currents and wind patterns combine to generate sea ice.

"As soon as sea ice is produced in these polyniers it is actually transported away from that so more sea ice can be produced," Dr Lieser said.

As the area covered in sea ice expands scientists have said the ice on the continent of Antarctica which is not over the ocean continues to deplete.

CEO of the Antarctic Climate and Ecosystems CRC, Tony Worby, said the warming atmosphere is leading to greater sea ice coverage by changing wind patterns.

"The extent of sea ice is driven by the winds around Antarctica, and we believe that they're increasing in strength and part of that is around the depletion of ozone," he said.

He said changes to sea ice levels could have implications for the entire Antarctic ecosystem.

"So the sea ice is a very important habitat for krill in particular and for the reproduction of krill and that forms one of the absolute staples of the diet for many species in the Antarctic."

While the Antarctic ecosystem braces for change, the world's Antarctic research vessels will also have to contend with treacherous conditions in the months ahead.

read more: http://www.abc.net.au/news/2014-09-14/record-coverage-of-antarctic-sea-ice/5742668

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Less cold equals more ice in some places — the wrong places. Read from top to understand this contrary situation... Meanwhile, 120 million cubic miles of ice shelf is lost from the Arctic and Antarctic, every year due to global warming.

Meanwhile in other places: 

Military specialists have blown up dikes in central Pakistan to divert swollen rivers and save cities from raging floods that have killed hundreds of people, authorities said on Saturday, as officials stepped up efforts in India’s part of Kashmir to prevent the spread of waterborne diseases there.

In Pakistan, the breaches at the overflowing Chenab River were performed overnight as floodwaters reached Multan, a city famous for its Sufi saints. Pakistani news channels showed pictures of floodwaters gushing through the blown-up dikes.

Civil and military officials have been using helicopters and boats to evacuate marooned people since 3 September, when floods triggered by monsoon rains hit Pakistan and the Kashmir region, which is divided between Pakistan and neighboring India.

Pakistan’s military said in a statement on Saturday that it was still evacuating people and air-dropping food in the districts of Multan, Muzaffargarh and Jhang. It said troops had air-dropped tonnes of food in flood-affected areas, while the army’s medical teams were also treating patients.

http://www.theguardian.com/world/2014/sep/14/pakistan-floods-military-blows-up-dikes-to-save-cities-from-floodwaters

In regard to my granddad's fridge, these represent some of the kitchen floor... (see at top)

Tuesday's high at Esperanza – which translates to "hope" in English – beat its previous record, set in 1976, by half a degree, according to the blog post's author Christopher Burt. The new maximum was also about 17 degrees above the March average for the site, he said.

Climate specialists say strong north-westerly winds may have contributed to the unusual warmth over the Antarctic Peninsula, creating a so-called Fohn wind effect. Esperanza is on the leeward side of the peninsula, and temperatures are being nudged higher as dry winds descend after losing their moisture through rain or snow on the mountains.

Reports of the record warmth in Antarctica come as a study published on Thursday in the journal Science found the region's massive floating ice shelves are shrinking as the globe warms up.

Unusual warmth over parts of Antarctica. Photo: University of Maine

The study, covering satellite observations of more than 1 million square kilometres from 1994-2012 found some shelves have shrunk 18 per cent in that time.

During the first half of that period, the overall decline of ice volume around Antarctica was small, with West Antarctica losses almost balanced out by gains in East Antarctica, Reuters reported. After that, western losses accelerated and gains in the east ended.

"There has been more and more ice being lost from Antarctica's floating ice shelves," Helen Fricker, a glaciologist of the Scripps Institution of Oceanography at the University of California said.

While Antarctic sea ice extent remains at or near record levels, the extra ice is less than a third of the loss of Arctic ice cover, climatologists say. The Arctic sea-ice extent is likely to report a record low this year in another sign of global warming, US agencies said this month.

While records may be melting at the Earth's polar extremes, the same was not true for Melbourne this week.

The chilliest March day on record was back in 1940, when the mercury made it to just 12 degrees, according to the Bureau of Meteorology.

read more: http://www.smh.com.au/environment/climate-change/record-warmth-reported-in-antarctica-as-melbourne-shivers-20150327-1m9455.html

See article about my granddad's refrigerator at top. 

One of the most troubling lines in the recent reports from the Intergovernmental Panel on Climate Change was tucked away in a footnote. It stated that, of their various future sea-level scenarios, the estimate of the upper limit – a 1.1 metre rise by 2100 – was actually not the worst case. That is, the $226 billion value of Australian roads, rail, commercial buildings and homes spread over the coastal zone that may be underwater regularly by 2100 could be an underestimate. And they did not know by how much.

The potential source of that extra water? A destabilised West Antarctic Ice Sheet. The unknown that niggled at the authors was the possibility that West Antarctica would do what observations and theory say is possible – collapse, adding an extra five metres to sea levels. Recent observations suggest irreversible retreat has now commenced, and so the key question is not if, but how quickly? The IPCC did not know and the science community still does not know (guesses on timescales vary from 200 to 1000 years or more).

But we are in a good position to begin to know. On Tuesday, April 21, I will deliver a lecture at the Royal Society in London describing remarkable progress in what we do know about Antarctica and its contribution to sea-level change. Thanks to international efforts coordinated by NASA and the European Space Agency we now know, for the first time in history and with great confidence, that the grounded ice of Antarctica is flowing into the ocean faster than snowfall replenishes it, hence raising sea levels. That imbalance is now 130 billion tonnes of ice each year.

And we know that this change is happening faster and faster – in both West Antarctica and Greenland. The big grounded ice sheets are now contributing to sea-level rises at double the rate they were in the 1990s. These changes have been observed in different ways, using different data, by different groups in different countries and the result is not disputed.

read more: http://www.smh.com.au/comment/shrinking-antarctic-has-us-skating-on-thin-ice-20150419-1mmvh4.html

Greenland, one of the largest ice sheets in the world, is melting. In fact, it is melting ahead of schedule as the world warms. Scientists are working hard to deepen their understanding of this ice sheet’s behavior so that we can predict how fast and how much of the ice sheet will melt in the coming decades and centuries.

It might seem obvious that in a warming world, the Greenland ice sheet will melt. But, what seems obvious and simple can be more complex when investigated more deeply. With respect to Greenland, it is expected that warmer temperatures increase melting but warmer temperatures can also mean more snowfall, as there is more moisture in warm air which can then fall as snow. So, it has been a question of which of these two competing processes would win out. Would Greenland get smaller because of melting or would it grow as more snow fell? 

Over the past few years, the verdict has become clear. The Greenland ice sheet is losing mass at an increasing rate. In fact, Greenland currently contributes twice as much as the Antarctic to rising sea levels. 

read more: http://www.theguardian.com/environment/climate-consensus-97-per-cent/2015/jul/14/global-warming-is-causing-rain-to-melt-the-greenland-ice-sheet

The Arctic, which is believed to contain as much as one-quarter of the world's undiscovered oil is part of a massive territorial dispute.

The United States, Russia, Canada, Denmark, Norway and Iceland are all laying claim to the area, with each country eager to tap into the oil, 30 percent of the earth's natural gas, and resources such as diamonds, gold and iron.

In August, Russia submitted a bid to the UN claiming a territory thought to hold $30tn worth of oil and gas.

Meanwhile, Canada has been scrambling to defend its territory against the US arguing that it is sovereign Canadian water, not an international waterway.

Amid the Arctic land grab, Iceland has also seized the opportunity for exploration.

Vanishing at 13 percent a decade, the melting ice is expected to make drilling, mining and shipping easier.

Gunnar Bragi Sveinsson, Iceland's foreign minister, joins Counting the Cost to discuss Iceland's plans for the Arctic and protecting the region from climate change.

See more: http://www.aljazeera.com/programmes/countingthecost/2015/09/cold-war-race-arctic-oil-gas-150905102034888.html

Of course, the more oil we burn from this region, the more ice will melt... Have we learnt something yet about global warming? Nupe... Greed rules...

Yet, if you look closely, there's one part of the planet that is bucking the trend. In the North Atlantic Ocean, south of Greenland and Iceland, the ocean surface has had very cold temperatures for the past eight months. What's up with that?

First of all, it's no error. Deke Arndt, chief of the climate monitoring branch at NOAA's National Centres for Environmental Information, confirmed what the map above suggests - some parts of the North Atlantic Ocean had record cold in the past eight months.

As Arndt said in an email: "For the grid boxes in darkest blue, they had their coldest Jan-Aug on record, and in order for a grid box to be 'eligible' for that map, it needs at least 80 years of Jan-Aug values on the record."

Those grid boxes encompass the region from "20W to 40W and from 55N to 60N", Arndt said.

And there's not much reason to doubt the measurements - the region is very well sampled.

"It's pretty densely populated by buoys, and at least parts of that region are really active shipping lanes, so there's quite a lot of observations in the area," Dr Arndt said. "So I think it's pretty robust analysis."

So, the record seems to be a meaningful one - and there is a much larger surrounding area that, although not absolutely the coldest it has been on record, is also unusually cold.

While there may not yet be any scientific consensus on the matter, at least some scientists suspect that the cooling seen in these maps is no fluke but, rather, part of a process that has long been feared by climate researchers - the slowing of Atlantic Ocean circulation.

In March, several top climate scientists, including Stefan Rahmstorf of the Potsdam Institute for Climate Impact Research and Michael Mann of Penn State, published a paper in Nature Climate Change suggesting that the gigantic ocean current known as the Atlantic Meridional Overturning Circulation, or AMOC, is weakening. It is sometimes confused with the "Gulf Stream" but, in fact, that is just a southern branch of it.

The current is driven by differences in the temperature and salinity of ocean water. In essence, cold salty water in the North Atlantic sinks because it is denser, and warmer water from further south moves northward to take its place, carrying tremendous heat energy along the way. But a large injection of cold, fresh water can, theoretically, mess it all up - preventing the sinking that would otherwise occur and, thus, weakening the circulation.

In the Nature Climate Change paper, the researchers suggested that this source of fresh water is the melting of Greenland, which is now losing more than a hundred billion tonnes of ice each year.

Antarctic ice is melting so fast that the stability of the whole continent could be at risk by 2100, scientists have warned.

Widespread collapse of Antarctic ice shelves – floating extensions of land ice projecting into the sea – could pave the way for dramatic rises in sea level.

The new research predicts a doubling of surface melting of the ice shelves by 2050. By the end of the century, the melting rate could surpass the point associated with ice shelf collapse, it is claimed.

read more: http://www.theguardian.com/environment/2015/oct/12/antarctic-ice-melting-so-fast-whole-continent-may-be-at-risk-by-2100

Read from top...

Further complicating matters is the sheets’ constant motion, as their immense weight causes them to flow outward from thick center toward thinner periphery. And the movement isn’t always slow and steady; glaciers extending out from the ice sheet can start, stop, speed up — erratically — as the ice rolls over bumps in bedrock or slides along on sheets of meltwater. More important, a glacier’s edges can break off suddenly and catastrophically into the sea, at times and places that remain difficult to anticipate. Arresting the big problems associated with climate change — punishing droughts, more powerful storms, lethal heat waves — often relates directly to whether human societies can scale back carbon emissions within a reasonable time. But ice sheets are a good example of how rising temperatures can tip natural systems into unknown territory. The warmth leads to repeating loops of cause and effect that can force ice sheets to flow faster, break faster, melt faster. Glaciologists may not be able to decipher the mysteries of ice sheets, to model their behavior and sensitivity, before calamity becomes inevitable.

At the moment, there are encouraging indications that the global community is poised to put decades of inaction behind it and address the carbon- dioxide emissions that have been driving air and ocean temperatures relentlessly upward. A United Nations- sponsored conference in Paris, scheduled for December, seeks to set emission targets that would keep the planet’s temperatures from rising two degrees Celsius (or about four degrees Fahrenheit) above the average for the industrial era, a benchmark thought to ensure that we will avoid the most catastrophic impacts of a warming world.

But there are clear warnings that the ice sheets have entered a phase of dangerous and unknown instability. To assess what this means for tomorrow requires looking back to long ago. The current research on sea- level rises during ancient eras — findings that are rarely discussed outside scientific circles — suggests that to regard the prospect of a future glacial collapse with only modest concern is to disregard what has happened in earth’s past, and what might happen again. ‘‘We know the ice can change fast,’’ Eric Rignot, a professor of earth sciences at the University of California, Irvine, told me in May, as we talked at a campus picnic table on a sunny afternoon. ‘‘We’ve never seen it. No human has ever seen it.’’ Rignot is fairly confident, however, that we are seeing it now — a conclusion borne out by the ice- sheet data he scrutinizes every week. A few decades from now, he said, we may look back with regret, wondering why more of us didn’t acknowledge the signs all around us, why we didn’t see ‘‘that the collapse had already started.’’

read more: http://www.nytimes.com/2015/11/15/magazine/the-secrets-in-greenlands-ice-sheets.html?hp&action=click&pgtype=Homepage&clickSource=story-heading&module=second-column-region&region=top-news&WT.nav=top-news&_r=0

"Any further recession of ice fronts there is likely to entail a non-negligible acceleration of the floating parts. In this regard, it is alarming that ice shelves in the Amundsen and Bellingshausen seas not only experienced the highest rates of subsurface melting, but also that thinning accelerated during the past two decades," the report said.

The study concluded that continued melting of the identified at-risk shelves, as a result of changing ocean currents and climate change, will considerably reduce buttressing "where it matters most for ice dynamics".

Professor of physical oceanography at the Institute of Marine and Antarctic Science, Nathan Bindoff, said the idea of "passive shelf ice" paper was a "clever way" of defining the areas most likely to cause the acceleration of ice melting.

"The heart of this paper is a method for telling us which ice sheets are most vulnerable in Antarctica so we can raise the alarm bells."

Professor Bindoff said the shelves most susceptible to ice loss are considered to be vulnerable due to the "very warm ocean waters" that can reach the cavities between the shelves.

"It all comes down to water temperature and access of those warm waters to the cavities themselves and the Amundsen and Bellingshausen seas have high access, while other areas are relatively safe."

One such area identified in the report was the Larsen C Ice Shelf, in the Weddell Sea, which "exhibits a large 'passive' frontal area," suggesting that the calving of an iceberg would be "unlikely to instantly produce much dynamic change," the report said.

While humans "aren't powerful enough to reshape the coastline, or able to put a bit of glad wrap [around] the ocean to stop warm water," Professor Bindoff said there are few ways of reducing future melting.

"The only obvious way is to cool the planet, and that is a long-term experiment, or to actually mitigate for climate change by reducing C02 emissions," he said. 

As humans emit heat-trapping gases into the atmosphere, it’s causing the Earth to warm. It’s also causing the ocean waters to rise. In fact, water rise is one of the clearest signatures of a warming world. The questions we want to answer are, how much will sea levels rise, and how fast? 

The answers to this have large implications on what societies should do. It isn’t just coastal communities that will be affected. While there are approximately 150 million people worldwide that live within 3 feet of today’s water levels, because of the interconnected economies and societies, ocean rise will affect us all.

The prestigious Proceedings of the National Academy of Sciences recently published a series of sea level rise papers.

One paper covers the Antarctic ice sheet, and the authors look back in time at the world’ largest ice sheet. The authors use three tools to advance our knowledge of the ice. First, they use a very accurate calculation approach to quantify how the ice sheet interacts with the atmosphere. Second, they incorporate potential ice fractures into their analysis. Finally, they use information about changes to oxygen isotopes to improve their calculations. What they find is that the atmospheric concentration of carbon dioxide will soon be at levels not encountered since the Miocene period (23 million to 5 million years ago). They also find that newer computer calculations do a better job of quantifying changes to the ice sheet.

A second paper published by Roelof Rietbroek and colleagues looked at the sources of sea level rise. They wanted to know how much of the current rise is from water that is warming and expanding, how much is from melting of ice sheets in Greenland and Antarctica, how much is from melting glaciers, how much is from shifting continents, etc. 

This study measured the mass of water in various regions of the Earth through special gravity-sensitive satellites that orbit the Earth. They conclude that the sea level rise from thermal expansion is higher than previously reported. The also find the water rise from melting of ice is consistent with measurements taken of ice melt around the world. Finally, they find that while the global oceans are rising steadily, there is tremendous regional variation so that some areas have very fast ocean water rise while others have slow ocean rise (or even ocean drop). 

The third paper by Robert Kopp and his colleagues uses statistics to find the relationship between temperature and sea level for the Common Era. They find that the sea level rise accelerated in the early 19th century and the rate of water rise in the last century is likely higher than it has been in 2,700 years. Their findings were in good agreement with those of the most recent IPCC report.

The final part of the foursome was authored by Matthias Mengel and his colleagues. That study uses historical information on sea level and climate change projections to make predictions about where ocean levels will be in the next 100 years or so. This study tries to separate how much sea level will rise because of various contributors, such as thermal expansion, melting mountain glaciers, the Greenland ice sheet, and the Antarctic ice sheet. 

When projecting into the future, the authors have to make decisions about how much more heat-trapping gases will be emitted into the atmosphere. To make the projections, the authors use the IPCC scenarios (RCP2.6, 4.5, and 8.5). A comparison between the new paper and the IPCC projections show excellent agreement. 

It appears that, unless societies make significant changes, we will see approximately 3 feet of sea level rise by 2100. That may not sound like a lot, but it’s enough to cause enormous economic and societal problems. What’s great about this paper is they also include a discussion on the limitations of their work. For instance, they state that their method cannot deal with processes that are independent of the warming rate (such as a sudden collapse of an ice sheet).

I wrote to the lead author to get his summary of the study and learn more about its importance. He told me,

Human influence on climate pushed the world’s oceans, glaciers and ice sheets away from their equilibrium so that they now all contribute to rising seas. As they are inert, a lot of their contribution will only be realized in the future. There is knowledge on how much they will add to sea level before they reach a new equilibrium, a process that can take thousands of years. We now combined this knowledge on long-term sea level rise with past observations into a small and efficient model. This allows us to make probabilistic projections of sea level rise incorporating the main uncertainties. 

While stopping sea level rise within this century is unlikely, our projections confirm that the world can still choose from a spectrum of sea level futures. It mainly depends on how much heat-trapping gases will be emitted. To avoid the risk of 1.3 meter higher seas in 2100, mankind needs to cut its carbon emissions.

As we saw in my last post, the actual costs to human society will depend not only on the rate and amount of seal level rise, but on how we humans adapt to this new reality.

http://www.theguardian.com/environment/climate-consensus-97-per-cent/2016/mar/11/sea-level-rise-is-accelerating-how-much-it-costs-is-up-to-us

Some people will get wet feet...

In recent years, climate scientists have grown increasingly concerned about a carbon problem in the far north.

The fear is that with the higher latitudes of the planet warming extremely rapidly, that heat itself, and some of its consequences — such as raging wildfires in northern forests — could unleash a climate disaster. Perennially frozen northern soils, known as permafrost, contain enormous amounts of carbon because the slow and cold chemistry of the Arctic makes them the repository of thousands of years of frozen plant remains. Warming could cause this plant matter to break down, be decomposed by bacteria and emit ancient carbon to the atmosphere in the form of carbon dioxide and methane.

And the amounts of carbon involved are enormous — one common estimate is that there’s more than twice as much carbon stored in northern permafrost as there is currently wafting about the planet’s atmosphere.

Now, though, a major and surprising new report from the U.S. Geological Survey would appear to undercut, significantly, this worry, at least for one key northern region: the U.S. state of Alaska. In the process, the document raises deep questions about what the true carbon consequences of Alaska’s ongoing warming will be — a mystery whose solution may also implicate still greater carbon stores across Arctic regions in Canada and Siberia.

read more: https://www.washingtonpost.com/news/energy-environment/wp/2016/06/03/alaskas-huge-climate-mystery-and-its-global-consequences/?hpid=hp_hp-more-top-stories_ee-alaska-819am%3Ahomepage%2Fstory

In this "surprising" report, a simple factor was overlooked. Albedo. whether the carbon sink works in positive, negative or neutral sum-total of CO2, the resultant of a "greening" Alaska or extreme northerly latitudes would be for a lowering of reflectance from the surface of the earth thus increasing the warming of such surface, itself compounding the process of global warming. Ignoring the methane emissions in this part of the world is akin to placing one's hand over a cold spot on a warming stove and declare the stove is cold. 

A "bombe Alaska" is a dessert with many variations — also called baked alaska... So whether less carbon dioxide is retained in the atmosphere in the latitudes of Alaska, there will be warming — possibly accelerating warming as these regions get "greener".

see also: https://www.rt.com/usa/345452-calabasas-brushfires-evacutation-homes/

Presently the weather in Sydney is crap, the weather in Paris is crap and the weather in Germany is crap...

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Scientists have discovered that thousands of blue lakes of melt water have formed on the surface of Antarctica's glaciers over the past decade, an unprecedented event which threatens the stability of the largest ice mass on Earth.

Last month, temperatures in the high Arctic spiked dramatically, some 36 degrees Fahrenheit above normal — a move that corresponded with record low levels of Arctic sea ice during a time of year when this ice is supposed to be expanding during the freezing polar night.

And now this week, as you can see above, we’re seeing another huge burst of Arctic warmth. A buoy close to the North Pole just reported temperatures close to the freezing point of 32 degrees Fahrenheit (0 Celsius), which is 10s of degrees warmer than normal for this time of year. Although it isn’t clear yet, we could now be in for another period when sea ice either pauses its spread across the Arctic ocean, or reverses course entirely.

Read more: 

https://www.washingtonpost.com/news/energy-environment/wp/2016/12/23/the...

Climatic banding was stable under "normal" conditions. Due to the GW melting of the Arctic, a new regimen of variation enters the system with more unpredictibility BUT WITH A GENERAL WARMING. This is explained in an ice cube in your whisky: as the ice melts, the whisky cools. You can even see minute surface currents where the ice is turning to cold water and mixes with the drink. The whisky becomes cold but the sum total of the ice/whisky is WARMING UP. What is happening on the north pole is the same on a huge scale. As well the air currents are slowing down with reversal of temperature gradients. The North pole is a complex system of high pressure (cold) and low pressure (warm) points with convection currents, including jet streams. Eventually, under present global warming conditions, the whole lot, including Siberia and the Northern US will WARM UP  — AS THERE WILL BE LESS COLD AVAILABLE FROM THE ARCTIC. Read from top. 

Global warming is real and anthropogenic. READ FROM TOP.

“The glaciers there are actively losing enough ice, and enough fresh water, that it’s important for the oceanography, and how the water changes as it goes up the west coast of Greenland,” says Willis. That in itself is proof that Greenland is melting quite a lot.

The big picture is that NASA’s new data suggest — that’s right — new vulnerabilities.

“Overall, together I think these papers suggest that the glaciers as a whole are more vulnerable than we thought they were,” Willis said. He says that, of course, with the aforementioned caveat that NASA is not ready yet to feed the data into a model that actually shows how this could play out over the decades of our future.

For now, we’re still stuck with official estimates from bodies such as the United Nations Intergovernmental Panel on Climate Change. The panel said in 2013 that Greenland’s melting might at most contribute 21 centimeters to sea-level rise by 2100, with some possible addition from rapid ice collapse (this is the high-end number for what scientists call the “likely” range in a worst-case global warming scenario, to be precise). But missions like OMG, in the meantime, are giving us plenty to worry about.

read more:

https://www.washingtonpost.com/news/energy-environment/wp/2017/02/10/nas...

By 2032, the whole climate banding will go totally out of whack. Already, the Arctic is running at up to 30 degrees Celsius above average and Greenland is up to 15 degrees C above average during this northern winter (2016-17). Meanwhile,  Australia, despite a weak La Nina, is experiencing record heat in the eastern part and record cold in the west with possible hails storm as never seen before. Weather patterns are taking a beating, including tornadoes in New Orleans during the northern winter. The only weather (though still warming fast) holding out is Antarctica, mostly due to the Antarctic size and the Antarctic Ocean acting like an "air conditioning unit — BUT THE PLANET IS WARMING FASTER THAN MOST (all) IPCC MODELS. 

Global warming is 99.999 per cent due to our burning of FOSSIL FUELS. Global warming REAL. Anyone disputing this should be placed in prison for crime against humanity and against the planet.

Global warming may seem abstract in other places far, far away from here. But Spitzbergen is ground zero for climate change. It is advancing here faster than elsewhere, offering an early taste of what global warming might mean. "Since November 2010, every single month has been unusually warm," says Kim Holmén, director of the Norwegian Polar Institute. "We see changes everywhere we look."

The fjord at Longyearbyen no longer freezes completely, for example, and salmon and even mackerel have moved in. Narwhals, meanwhile, have migrated further north.

The glaciers are melting with unexpected speed, especially in the west of Spitzbergen. Whereas some of them calved into the ocean for centuries, they now come to a stop before they reach the sea. And every year, the thaw is longer. "On average, the winters are 10 degrees Celsius warmer than they were 20 years ago," says Holmén. This region should be dry like a desert, but the amount of regular precipitation has now increased several-fold. Suddenly Longyearbyean's steep slopes have become a mortal danger because the increased snowfall can't stick to their icy surfaces.

In late 2015, a two-year-old and her father died when an avalanche carried away their house. In early 2017, another wall of snow and rocks thundered into the valley. Since then, authorities have declared dozens of houses uninhabitable with some residents now slated to move closer to the fjord. "Lots of people here are afraid," says Hilde Røsvik, editor-in-chief of the local newspaper, Svalbardposten.

read more:

http://www.spiegel.de/international/world/research-on-global-warming-loo...

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A new study from Chinese and South Korean universities has looked into the complex interactions of climate systems to try to understand why the warming of the Arctic has caused more intense and lengthy winters elsewhere.

The National Oceanic and Atmospheric Administration (NOAA) announced in 2014 that the winter of 2013-2014 was the coldest on record for the American midwest. They referred to it as a "polar freeze" or "Arctic freeze," terms that caught on with the public. So the notion went, global warming had heated the Arctic, which had caused cold weather patterns elsewhere. 

But the trend is more complex than many believe. "The link found between Arctic warming and continental cooling is probably not a simple cause–effect mechanism," wrote study contributor Ana Bastos, a researcher at the French Laboratoire des Science du Climat et de l'Environement. Bastos added that shifts in climate vary from region to region.

Researchers from Pohang University of Science and Technology in South Korea and the South University of Science and Technology of China studied data related to these teleconnections to better understand the relations between two very different climate systems: the Arctic and North America. 

As the Arctic warms, the researchers found, atmospheric patterns shift. This has numerous effects, including a reduction of precipitation over the South-Central United States and increased pressures for plants that can only thrive in narrow temperature bands. This can lead to a feedback loop, as plants are net carbon absorbers (compared to animals, which are net carbon producers). A North American plant die-off would not only be an economic pressure, it could increase the amount of carbon in the atmosphere and accelerate the warming of the Arctic.

There are other factors at play. The melting of Arctic ice sends cold water flowing down from the Arctic Ocean into the Atlantic and Pacific. The breaking of ice shelves into the sea can lead to the release of ice trapped inside of the shelf. However, the trend itself is difficult to deny.

read more:

https://sputniknews.com/environment/201707121055457160-climate-systems-american-polar-freeze/

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Sea ice levels in Antarctica dropped to a record low this year, but experts say there is not a clear link to climate change.

More than 60 meteorologists and scientists from around the world are holding a week-long meeting in Hobart, Tasmania, to better understand sea ice changes on the frozen continent.

Dr Jan Lieser from the Antarctic Climate and Ecosystems Cooperative Research Centre said sea ice levels had experienced a “massive increase” in variability over the past few years.

Sea ice coverage fell to 2.075m sq km in March, the lowest since satellite observations began in 1979. But just three years earlier it hit a record high of more than 20m sq km.

Lieser said increasing ocean surface temperatures melt the ice but may also be helping it refreeze. 
“More warmth into the system reduces the sea ice cover but there’s also other mechanisms,” he said. “Increased warmth increases the melt underneath shelves – that increases the fresh water balance of the ocean.

“Fresh water more readily freezes at the surface, which increases the sea ice again.”

read more:

https://www.theguardian.com/world/2017/sep/26/antarctic-sea-ice-levels-h...

READ FROM TOP AND YOU WILL KNOW WHY...

Coal use will have to be "pretty much" gone by mid-century if the planet is to avoid sea-level rise of more than a metre by 2100 as Antarctic ice sheets disintegrate faster than expected, new modelling by an Australian-led team has found. 

On business-as-usual projections, sea-level rise by the end of the century could exceed 1.3 metres compared with the 1986-2005 average, or 55 per cent more than predicted in the Fifth Assessment Report by the Intergovernmental Panel on Climate Change, according to research published in the Environmental Research Letters journal.

read more:

http://www.smh.com.au/environment/climate-change/coal-use-must-pretty-mu...

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"The Arctic has traditionally been the refrigerator of the planet but the door to that refrigerator has been left open," he added.

Read more:

https://sputniknews.com/environment/201712141059980816-unprecedented-tra...

Read from top... The Arctic might be the "refrigerator of the planet"  but the Antarctic has been the Freezer... Things are not looking good...

Meanwhile:

Sydney is bracing itself for summer’s first heatwave, and it might not let up until mid-next week.

Read more: https://tenplay.com.au/news/national/december-2017/sydney-swelters-through-heatwave

The previous, most extensive survey of this kind assessed just 16 cores. The new study is therefore much more representative of snowfall behaviour across the entire continent. 

It found the greater precipitation delivered additional mass to the Antarctic ice sheet at a rate of 7 billion tonnes per decade between 1800 and 2010 and by 14 billion tonnes per decade when only the period from 1900 is considered. 

Most of this extra snow has fallen on the Antarctic Peninsula, which saw significant increases in temperature during the 20th Century. 

"Theory predicts that, as Antarctica warms, the atmosphere should hold more moisture and that this should lead therefore to more snowfall. And what we're showing in this study is that this has already been happening," Dr Thomas said.

Read more:

http://www.bbc.com/news/science-environment-43691671

Global warming is real and anthropogenic.

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The Antarctic ice sheet has lost more than 2,500 billion tonnes of ice in the past 25 years and nearly half of that has happened since 2012.

An international team of polar scientists found that melting in Antarctica has jumped sharply from an average of 76 billion tonnes per year prior to 2012, to around 219 billion tonnes each year between 2012 and 2017.

That's adding 0.6 of a millimetre to sea levels each year. Antarctica stores enough water to raise global sea levels by 58 metres, and has contributed 7.6 millimetres since 1992, according to the research published in Nature today.

The latest data is a continuation of previous assessments known as the Ice sheet Mass Balance Inter-comparison Exercise (IMBIE), which began in 2011 and tracks ice-sheet loss from 1992 onwards.

IMBIE was established with the support of NASA and the European Space Agency, to monitor the changes in ice-sheet cover around the world.

It uses combined satellite data to measure the Antarctic ice sheet's changing flow and volume.

The increase in melting should act as a wake-up call, according to project leader Professor Andrew Shepherd from the University of Leeds.

Read more:

http://www.abc.net.au/news/science/2018-06-14/antarctica-sea-level-rise/...

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(WASHINGTON) — Antarctica is melting more than six times faster than it did in the 1980s, a new study shows.

Scientists used aerial photographs, satellite measurements and computer models to track how fast the southern-most continent has been melting since 1979 in 176 individual basins. They found the ice loss to be accelerating dramatically — a key indicator of human-caused climate change.

Since 2009, Antarctica has lost almost 278 billion tons (252 billion metric tons) of ice per year, the new study found. In the 1980s, it was losing 44 billion tons (40 billion metric tons) a year.

The recent melting rate is 15 percent higher than what a study found last year.

Eric Rignot, a University of California, Irvine, ice scientist, was the lead author on the new study in Monday’s Proceedings of the National Academy of Sciences. He said the big difference is that his satellite-based study found East Antarctica, which used to be considered stable, is losing 56 billion tons (51 billion metric tons) of ice a year. Last year’s study, which took several teams’ work into consideration, found little to no loss in East Antarctica recently and gains in the past.

Melting in West Antarctica and the Antarctica Peninsula account for about four-fifths of the ice loss. East Antarctica’s melting “increases the risk of multiple meter (more than 10 feet) sea level rise over the next century or so,” Rignot said.

Richard Alley, a Pennsylvania State University scientist not involved in Rignot’s study, called it “really good science.”

Read more:

http://time.com/5502561/antarctica-losing-ice-climate-change/

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Greenland is losing ice seven times faster than it was in the 1990s. 

The assessment comes from an international team of polar scientists who've reviewed all the satellite observations over a 26-year period. 

They say Greenland's contribution to sea-level rise is currently tracking what had been regarded as a pessimistic projection of the future.

It means an additional 7cm of ocean rise could now be expected by the end of the century from Greenland alone.

This threatens to put many millions more people in low-lying coastal regions at risk of flooding. 

It's estimated roughly a billion live today less than 10m above current high-tide lines, including 250 million below 1m. 

"Storms, if they happen against a baseline of higher seas - they will break flood defences," said Prof Andy Shepherd, of Leeds University.

"The simple formula is that around the planet, six million people are brought into a flooding situation for every centimetre of sea-level rise. So, when you hear about a centimetre rise, it does have impacts," he told BBC News.

• Greenland's ice faces melting 'death sentence'
• UN panel signals red alert on 'Blue Planet'
• Antarctica's ice melt 'has accelerated'

Scientists on an unusual expedition, known as the Multidisciplinary Drifting Observatory for the Study of Arctic Climate (MOSAiC), are spending 1 year drifting with the pack ice, collecting data on how climate change is affecting the environment. But they have to contend with a force that can throw off their measurements: their own ship. The 118-meter-long Polarstern is a sophisticated floating lab that allows MOSAiC scientists to study the atmosphere, sea ice, ocean, and life. But the vessel and the equipment it carries also produce noise, light, heat, and other forms of pollution that can ruin measurements in this pristine environment.

An Antarctic glacier larger than the UK is at risk of breaking up after scientists discovered more warm water flowing underneath it than previously thought.

The fate of Thwaites – nicknamed the doomsday glacier – and the massive west Antarctic ice sheet it supports are the biggest unknown factors in future global sea level rise.

Over the past few years, teams of scientists have been crisscrossing the remote and inaccessible region on Antarctica’s western edge to try to understand how fast the ice is melting and what the consequences for the rest of the world might be.

“What happens in west Antarctica is of great societal importance,” said Dr Robert Larter, a scientist with the British Antarctic Survey and principal investigator with the International Thwaites Glacier Collaboration, the most ambitious research project ever carried out in Antarctica. “This is the biggest uncertainty in future sea level rise.”

The ITGC’s $50m research drive has sent teams of scientists to the region to use the latest scientific tools to better understand the speed of the melting and the stability of the glacier.

This month one of the ITCG’s teams, which had managed to get an uncrewed submarine under the front of Thwaites for the first time, published a study showing more relatively warm water was reaching the glacier than previously thought, triggering concerns of faster melting.

Anna Wahlin, a professor of oceanography at the University of Gothenburg who led the study, said the findings suggested that the fate of the glacier and the west Antarctic ice sheet would be sealed in the next two to five years. “The coming years will be crucial … they will determine what happens to this glacier,” she said.

Wahlin said the front of the Thwaites glacier was resting on a number of “pinning points” under the sea. But as relatively warm water from the deep ocean increased the melting, she said, these would be lost, breaking up the ice and allowing warm water further under the ice. This would speed up the flow of the glacier into the sea.

“It could be that once that happens everything falls apart and this is just the beginning of some quite dramatic change … but if it doesn’t happen now I think we can be more confident that it is not going to happen as the worst-case scenarios,” Wahlin said.

The worst-case scenarios for Thwaites are grim. It is the widest glacier on the planet, more than 1km deep and holds enough ice to raise the sea level by 65cm.

Ice loss has accelerated in the last 30 years and it now contributes about 4% of all global sea level rise. Experts say this could increase dramatically if the ice at the front of Thwaites breaks up, with knock-on effects for other glaciers in the area.

To heighten scientists’ concerns, west Antarctica has been one of the fastest-warming place on Earth in the past 30 years, and since 2000 it has lost more than 1tn tons of ice.

Last year, a team of British scientists discovered cavities half the size of the Grand Canyon under Thwaites that, like decay in a tooth, allow warm ocean water to erode the glacier, internally accelerating melting. And because a lot of the ground on which the glacier sits is below sea level, it is thought to be particularly vulnerable to melting as warmer water encroaches further under the ice inland.

Larter said: “The bed gets deeper upstream and there is a glaciological theory that says this is potentially a very unstable situation … it is a very scary scenario when you first hear it, but there are various negative feedback scenarios that might counter it.”

He said if the glacier’s “pinning points” were lost in the next few years it would start to flow faster “and put more ice into the sea”. But he said the question no one could currently answer was exactly how much extra ice will go into the sea if the glacier begins to break up.

“That is a tricky question,” said Larter. “I think I would have to say come back in a couple of years.”

He added: “Nobody knows how it is going to respond to persistent warming – we don’t know because in human history we have never seen it happen. We are trying in every way we can to get a handle on what is going to happen.”

Ella Gilbert, a research scientist at the University of Reading, said what was happening in the polar regions demanded an urgent response from the international community.

“The polar regions are the canary in the coalmine – they are the symbol of climate change,” said Gilbert, who was a joint author of a recent study warning of the catastrophic impact of global heating on Antarctic ice.

Read more:

https://www.theguardian.com/environment/2021/apr/30/antarctic-doomsday-glacier-may-be-melting-faster-than-was-thought

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Note: the melting water of floating ice is "shrinking" a tad volume-wise when warming from 0 to 4 degrees Celsius. Above 4 degrees Celsius, the water expands and contributes to the rising of sea level.

assange2

An alarming crackup has begun at the foot of Antarctica’s vulnerable Thwaites Glacier, whose meltwater is already responsible for about 4% of global sea level rise. An ice sheet the size of Florida, Thwaites ends its slide into the ocean as a floating ledge of ice 45 kilometers wide. But now, this ice shelf, riven by newly detected fissures on its surface and underside, is likely to break apart in the next 5 years or so, scientists reported today at a meeting of the American Geophysical Union.

The most dramatic sign of impending failure is a set of diagonal fractures that nearly span the entire shelf. Last month, satellites spotted accelerating movement of ice along the fractures, says Erin Pettit, a glaciologist at Oregon State University, Corvallis, who is part of a multiyear expedition studying the glacier. The shelf is a bit like a windshield with a series of slowly opening cracks, she says. “You’re like, I should get a new windshield. And one day, bang—there are a million other cracks there.”

Once the ice shelf shatters, large sections of the glacier now restrained by it are likely to speed up, says Ted Scambos, a glaciologist at the University of Colorado, Boulder, and a leader of the Thwaites expedition. In a worst case, this part of Thwaites could triple in speed, increasing the glacier’s contribution to global sea level in the short term to 5%, Pettit says.

Even more worrisome is the process that has weakened the ice shelf: incursions of warm ocean water beneath the shelf, which expedition scientists detected with a robotic submersible. Because Thwaites sits below sea level on ground that dips away from the coast, the warm water is likely to melt its way inland, beneath the glacier itself, freeing its underbelly from bedrock. A collapse of the entire glacier, which some researchers think is only centuries away, would raise global sea level by 65 centimeters. And because Thwaites occupies a deep basin into which neighboring glaciers would flow, its demise could eventually lead to the loss of the entire West Antarctic Ice Sheet, which locks up 3.3 meters of global sea level rise. “That would be a global change,” says Robert DeConto, a glaciologist at the University of Massachusetts, Amherst. “Our coastlines will look different from space.”

Although it is unclear whether the shelf will fall apart in 1 year or 10 years, Pettit and her colleagues are pursuing important work, adds DeConto, who is unaffiliated with the Thwaites team. The oceans are simply getting too warm for these marine ice sheets, which formed in conditions much cooler than today, he says. “This marine-based ice is not going to come back.”

Exploring the future of this keystone of the West Antarctic Ice Sheet is the aim of the International Thwaites Glacier Collaboration (ITGC), a multiyear, more than $50 million expedition funded by the United States and United Kingdom. The glacier, far from any research stations, is challenging to reach under the best circumstances, and ITGC’s first scientific campaign on the ice, in the Antarctic summer of 2019–20, contended with severe storms. But the team managed to erect several temporary camps, including one in the middle of the ice shelf and another farther upstream, near the grounding line where the glacier detaches from the continent.

Read more:

Science, Vol 374, Issue 6574.

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FREE JULIAN ASSANGE NOW !!!!!!!!!!!!!!

HAVE WE BEEN WRONG HERE? HAVE WE MISUNDERSTOOD THE SIGNS? IS IT POSSIBLE THAT THEY ARE RIGHT?

THE ANSWER TO THIS IS NO. BEFORE LETTING OTHERS EXPLAIN THEIR VIEWS, LET'S SAY THAT THEY ARE WRONG... 

WE MAINTAIN THAT GLOBAL WARMING IS ANTHROPOGENIC. IT IS INDUCED BY OUR BURNING OF FOSSIL FUELS. IT IS NOT TOO OBVIOUS YET, BECAUSE OF THE MELTING OF THE ICE IN VARIOUS PARTS OF THE WORLD. IT IS WHAT WE'VE EXPOSED IN MANY ARTICLES ABOUT THE "ICE IN THE WHISKY SYNDROME". THE ICE IS MELTING AND THE WHISKY IS GETTING COOLER. BUT THE SUM-TOTAL OF TEMPERATURE INTHE SYSTEM IS GOING UP.

DESPITE THE ICE MELTING, THERE ARE STILL INDICATIONS OF RECORD WARM AROUND THE WORLD INCLUDING THE OCEANS. SEE https://yourdemocracy.net/drupal/node/33287 TO GET A BASIC GRIP ON THIS MAJOR PROBLEM.

HERE IS THE BULLSHIT:

There is no climate emergency. As I have been saying for years, the climate change agenda to end fossil fuels is merely a fraudulent cause intended to gain power. The Global Climate Intelligence Group (CLINTEL) is an independent foundation founded in 2019 by emeritus professor of geophysics Guus Berkhout and science journalist Marcel Crok. “The climate view of CLINTEL can be easily summarized as: There is no climate emergency.” Over 1540 experts respected in their independent fields have joined CLINTEL to spread the message that there is no scientific data to indicate that climate change is political propaganda.

THIS IS MISINFORMATION. BEWARE. 

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