Arctic circle could become completely free of sea ice even if global warming limited to two degrees Celsius

Loss of sea ice could have 'catastrophic' effects on the weather in much of the northern hemisphere and speed up global warming.

The Arctic Ocean could become free of sea ice for the first time in 100,000 years even if action is taken to keep global warming to within two degrees Celsius, scientists have warned.

The region has experienced much sharper rises in temperature in recent decades that the rest of the world with temperatures in winter in Spitsbergen an astonishing 8 to 11C higher than the average between 1961 and 1990.

And this is believed to be having a significant effect on the weather in much of the northern hemisphere, increasing the number of dangerous storms. One leading expert has warned it could have a “catastrophic” effect on the Earth’s climate.

The loss of sea ice, which reflects much of the energy from sunlight, will also increase the rate of global warming.

In a paper in the journal Nature Climate Change, Dr James Screen and Dr Daniel Williamson, of Exeter University, looked at the likelihood of the ice disappearing almost completely if temperatures rose by 1.5C or 2C.

The Paris Agreement on climate change spoke of keeping global warming below 2C and as close to 1.5C as possible – in order to avoid levels considered particularly dangerous – but the world is currently on track to hit anything from 2.6C to 3.1C by the end of the century.

The researchers wrote: “We estimate there is less than a one-in-100,000 chance of an ice-free Arctic if global warming stays below 1.5C, and around a one-in-three chance if global warming is limited to 2C. 

“We suppose then that a summer ice-free Arctic is virtually certain to be avoided if the 1.5C target of the Paris Agreement is met. 

“However, the 2C target may be insufficient to prevent an ice-free Arctic.”

The Arctic will be considered ice-free if it falls to below a million square kilometres. This would mean the sea around the North Pole would be clear with the remaining ice found mainly in the small islands and inlets off the north coasts of Russia and Canada, where the effect of the land, which gets colder than the sea, is more pronounced.

In September last year, Arctic sea ice fell to about 4.1 million square kilometres, the second lowest figure, compared to about 3.4 million in 2012, according to the US National Snow & Ice Data Centre.

Antarctic sea ice is currently at record low levels with 2.14 million square kilometres, compared to the average of 3.16 million between 1981 and 2010.

In December, the US National Oceanic and Atmospheric Administration (NOAA) said the situation was changing so quickly it was “outpacing our ability to understand and explain” what was happening.

They suggested the word “glacial” should not be used to mean something happening slowly but as a term for something that was “rapidly diminishing”.

New Study Shows No Global Warming Pause

UNITED STATES—There has not been a pause in global warming according to newly published findings. A new study in the journal “Science Advances” back an earlier NOAA study that came to similar conclusions.

According to The Washington Post, a 2015 NOAA study contradicted an argument questioning the scientific consensus on climate change.

“The skeptics had for years suggested that following the then-record warm year of 1998 and throughout the beginning of the 21st century, global warming had slowed down or ‘paused,’” the article states. “But the 2015 paper, led by NOAA’s Thomas Karl, employed an update to the agency’s influential temperature dataset, and in particular to its record of the planet’s ocean temperatures, to suggest that really, the recent period was perfectly consistent with the much longer warming trend.”

The article goes on to explain that the study caused controversy in Congress.

“It actually led to a congressional subpoena from Rep. Lamar Smith, chair of the House Committee on Science, who charged that ‘NOAA’s decision to readjust historical temperature records has broad national implications’ and requested more information on why NOAA had made the dataset adjustment, including data and communications from the scientists involved,” the article says.

A new study published on January 4 supports the findings of the earlier NOAA study. The study’s lead authors, Kevin Cowtan and Zeke Hausfather, wrote a blog post for Scientific American on their study and the political controversy around the older NOAA findings.

“Our results suggests that the new NOAA record is likely the most accurate of the various sea surface temperature records during the past two decades, and should help resolve some of the criticism that accompanied the original NOAA study,” the Washington Post said.

“However the scientific question of how fast the Earth has been warming over the past two decades can be answered by replication from the scientific community, not by a political investigation. And the best evidence we have says that NOAA got it right,” the post says.

The new study can be found here.

Antarctica found amplifying effects of climate change during last global warming

SAN FRANCISCO -- A a new study indicates that the Antarctic warmed about 11 degrees Celsius between about 20,000 and 10,000 years ago while the average temperature worldwide rose about 4 degrees Celsius following Earth's last ice age.

The disparity, that the Antarctic warmed nearly three times the average temperature increase worldwide after the peak of last ice age 20,000 years ago, highlights the fact that the poles, both the Arctic in the north and the Antarctic in the south, amplify the effects of a changing climate, whether it gets warmer or cooler.

As the calculations are in line with estimates from most climate models,"the result is not a surprise, but if you look at the global climate models that have been used to analyze what the planet looked like 20,000 years ago, the same models used to predict global warming in the future, they are doing, on average, a very good job reproducing how cold it was in Antarctica," said Kurt Cuffey, a glaciologist at the University of California, Berkeley.

The models predict that as a result of current global climate change, Antarctica will warm twice as much as the rest of the planet and reach its peak in a couple of hundred years. Given business-as-usual greenhouse gas emissions, a global average increase of 3 degrees Celsius by 2100 and a rise of around 6 degrees in the Antarctic is predicted.

During the last period of global warming, the ice deep inside the Antarctic glaciers warmed more slowly than Earth's surface. By measuring the remaining difference, that the 20,000-year old ice deep in the West Antarctic ice sheet is about 1 degree Celsius cooler than the surface, the researchers were able to estimate the original temperature based on how fast pure ice warms up.

Gary Clow of the U.S. Geological Survey in Lakewood, Colorado, measured in 2011 and again in 2014 the temperature in a 3.4-kilometer-deep borehole from which the West Antarctic Sheet Divide ice core had been drilled during an eight-year project that ended in 2011. Ice at the bottom of the borehole was deposited about 70,000 years ago; ice about one-sixth of the way up about 50,000 years ago; and ice about one-third of the way to the surface 20,000 years ago.

Cuffey, first author of the study recently published in the Proceedings of the National Academy of Sciences, developed a technique to combine these temperature measurements with isotopic measurements of old ice to come up with an estimated temperature of 11.3 degrees, plus or minus 1.8 degrees Celsius, warming since the depths of the ice age.

The Antarctic temperature rose much more rapidly than did Arctic temperatures after the glacial maximum. By 15,000 years ago, Antarctica had warmed to about 75 percent of its temperature today. The Arctic took another 3,000-4,000 years to warm this much, primarily because the Northern Hemisphere had huge ice sheets to buffer warming, and changes in ocean currents and Earth's orbital configuration accelerated warming in the south.

Antarctica was also more sensitive to global carbon dioxide levels, Cuffey was quoted as saying in a news release from UC Berkeley, adding that the situation today, with global warming driven primarily by human emissions of carbon dioxide from burning fossil fuels, is different from natural cycles. The ability of the oceans to take up carbon dioxide cannot keep up with the rising levels of greenhouse gases in the atmosphere, meaning carbon dioxide and global temperatures will continue to increase unless humans cut their emissions.

2016 'very likely' to be world's warmest year

2016 looks poised to be the warmest year on record globally, according to preliminary data.

With data from just the first nine months, scientists are 90% certain that 2016 will pass the mark set by 2015.

Temperatures from January to September were 1.2C above pre-industrial levels, according to the World Meteorological Organization (WMO).

The body says temperatures should remain high enough for the rest of the year to break the previous record.

El Nino has had an impact, but the most significant factor driving temperatures up continues to be CO2 emissions.

What is climate change?

The provisional statement on the status of the global climate in 2016 has been released early this year to help inform negotiators meeting in Morocco, who are trying to push forward with the Paris Climate Agreement.

The document says the year to September was 0.88 above the average for the period between 1961-90, which the WMO uses at its baseline.

The whole of 2015, which broke the previous record by a significant amount, was 0.77 above the 1961-90 average.

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While there are still a couple of months to go this year, a preliminary analysis of the October data indicates that 2016 is very much on track to surpass the 2015 level, which in turn broke the previous high mark set in 2014.

"Another year. Another record. The high temperatures we saw in 2015 are set to be beaten in 2016," said WMO secretary-general Petteri Taalas.

"In parts of Arctic Russia, temperatures were 6C to 7C above the long-term average. Many other Arctic and sub-Arctic regions in Russia, Alaska and north-west Canada were at least 3C above average. We are used to measuring temperature records in fractions of a degree, and so this is different," said Mr Taalas.

The report highlights the fact that other long-term climate change indicators are also breaking records. The amount of greenhouse gas in the atmosphere continued on its upward march in 2016.

Arctic sea ice continued to melt in significant amounts, while the Greenland ice sheet displayed very early melting this year.

Experts believe that the El Nino weather phenomenon played a role in the record warm temperatures seen in 2015 and 2016.

They quantify it as roughly 0.2 of a degree - but the bulk of the warming is coming from the accumulation of greenhouse gases. And the impacts of that warming are being widely felt.

"Because of climate change, the occurrence and impact of extreme events has risen," said Petteri Taalas.

"'Once in a generation' heatwaves and flooding are becoming more regular. Sea level rise has increased exposure to storm surges associated with tropical cyclones," he said.

The surprise election of Donald Trump as president of the US has increased expectations that he will bring a more sceptical view of climate change to the White House.

Scientists are stressing that the evidence for the reality of climate change is getting stronger all the time.

"We are seeing the impacts of climate change on extreme weather," said Dr Peter Stott, who leads the climate attribution team at the UK Met Office.

"One degree may sound a relatively small number but in the context of such a stable climate that we've had over the past millennia, and the rapidity of that warming, we are seeing this real world evidence that doesn't come from a model or a projection."

According to the WMO analysis, 16 of the 17 warmest years have been recorded this century. The only exception was 1998.

 

Least Developed Countries Call for 'Ambitious Action' at COP22

Achieving the crucial 1.5°C target will require immediately halting new fossil fuel development now.

The chair of the Least Developed Countries group, Tosi Mpanu-Mpanu, called for “fair and ambitious action” Monday at the next round of international climate change negotiations which begin on Nov. 7 in Marrakech, Morocco.

Mpanu-Mpanu, senior negotiator for the Democratic Republic of Congo on climate issues, said that the next round of UN climate talks, COP22, must be “an action and implementation COP” and must “construct robust rules to support the [Paris] Agreement's implementation.”

ANALYSIS: 5 Ways the COP21 Deal Dooms the Planet to Climate Change Chaos

Mpanu-Mpanu expressed his concern that even with a full implementation of the Paris Agreement, which comes officially into force on Nov. 4, current pledges by countries to cut greenhouse gas emissions puts the world on track for 3-3.5°C of warming above pre-industrial levels.

“Science tells us that beyond temperature increases of 1.5°C the future of our planet stands on increasingly thin ice. We cannot afford to treat this as an aspirational goal,” he said.

According to Payal Parekh, program director at climate action group 350.org, achieving the crucial 1.5°C target will require immediately halting new fossil fuel development now. “Around the world, there is a powerful and growing fossil fuel resistance movement that is pushing our institutions and governments to divest and break free from fossil fuels to prioritize people and the planet,” added Parekh.

RELATED: Activists Shut 5 Canada-US Pipelines to Support Standing Rock

With this goal in mind the LDC group plans to launch their Renewable Energy and Energy Efficiency Initiative for Sustainable Development at the UN conference. Mpanu-Mpanu said the plan “demonstrates the continued commitment of the LDC group to real solutions that benefit real people on the ground.”

The Initiative, according to Mpanu-Mpanu, will enable LDCs to leapfrog fossil fuel based energy and generate prosperity by bringing “modern, clean, resilient energy systems to millions of energy-starved people."

The LDC group is made up of 48 primarily African nations that are especially vulnerable to climate change but have done the least to cause the problem. They came together to demand that wealthier nations act in accordance with their responsibility for creating the climate problem and their capability for addressing it.

The talks in Morocco take place in the midst of massive protests over the recent killing of a fish seller in the coastal community of Al Hoceima which has been hard hit by severe government restrictions on small-scale fishermen in response to declining fish populations linked to climate change.

  • Published in World

Species may be listed as threatened based on climate change projections, court says

Federal authorities may list a species as “threatened” based on climate models that show habitat loss in the coming decades, an appeals court decided Monday.

The state of Alaska, oil company groups and Alaskan natives had challenged a decision by the federal government to list a sea ice seal subspecies as threatened and deserving of protection. 

The  challengers maintained the subspecies’ population was currently healthy and the climate projections were speculative.

 A three-judge panel of the San Francisco-based U.S. 9th Circuit Court of Appeals disagreed. The ruling would allow government protection of all sorts of wildlife likely to be affected by climate change in the decades ahead.

The panel decided unanimously that the National Marine Fisheries Services reasonably determined that loss of Arctic sea ice over shallow waters would “almost certainly” threaten the survival of a Pacific bearded seal subspecies by the end of the century.

“The service need not wait until a species’ habitat is destroyed to determine that habitat loss may facilitate extinction,” Judge Richard A. Paez, a Clinton appointee, wrote for the court.

The bearded seals are among several species, including the polar bear,  that the government has classified as threatened because of climate change.

A lawyer for an environmental group that sought the listing said the 9th Circuit decision was particularly significant because it allowed for protection of a species based on models of conditions at the end of the century.

“This legal victory is likely to have major implications for many other climate-threatened species,” said Kristen Monsell, a staff attorney for the Center for Biological Diversity, which sought the listing.

The state and the oil and gas industry opposed the listing because it could interfere with offshore drilling.

Before issuing a permit to drill, the federal government would have to determine whether the activity would affect the bearded seal. If so, the company’s exploration could be restricted.

A lawyer for the state of Alaska said the ruling may be appealed.

”If this opinion stands, the National Marine Fisheries Service would list a species that is abundant and in good health based on the claim that climate change will impact habitat over the next 100 years and may cause harm,” said Brad Meyen, senior assistant attorney general for Alaska.

A lawyer for the oil and gas industry could not be reached for comment.

The bearded seals congregate on ice floes over shallow waters, where they give birth to pups and nurse. The floes give the nursing mothers close access to food sources — organisms on the ocean floor — and enable the pubs to learn to dive, swim and hunt away from their predators, the court said.

Climate models show that the ice floes would disappear during breeding times, and mother seals would have to nurse their young on shore, where they would be vulnerable to predators such as polar bears and walruses.

A lack of ice floes in shallow waters also would force the seals to forage in the deeper ocean, which contains fewer of the organisms they depend on for survival, the government found.

One peer reviewer said the 80-year prediction was more likely than not to “greatly” underestimate the impact of climate change on the seals.

“All parties agree that there will be sea ice melt,” the court said. “The only uncertainty is the magnitude of warming, the speed with which warming will take place, and the severity of its effect.”

 Although climate projections for 2050 through 2100 may be volatile, they remain valuable in the government rule-making process, the court found.

The Endangered Species Act does not say a species can be listed “only if the underlying research is ironclad and absolute,” Paez wrote.

“It simply requires the agency to consider the best and most reliable scientific and commercial data and to identify the limits of that data when making a listing determination,” the court concluded.

Damage on Climate Change to Agriculture Grows, FAO Says

Havana, Oct 18 (Prensa Latina) FAO representative in Cuba, Theodor Friedrich, said here that climate change has been increasingly affecting agricultural production more visibly and threatening to overcome the goal of eradicating hunger by 2030.
 
Friedrich made that statement on occasion of the World Food Day (WFD) and the founding of the Food and Agricultural Organization (FAO), to which participants at the International Experts Consultation on Conservation Agriculture (CA), opened yesterday at the Comodoro Hotel, attended.

The resident coordinator of the United Nations System in Cuba, Myrta Koulard, other officials at FAO Office, the Ministry of Agriculture (MINAG) and members of the diplomatic staff, also participated.

Cuba has faced two years of drought and recently a category-four hurricane. This proved how the forces of nature can work against the efforts to ensure food production for future generations, Friedrich said.

He also stated that the WFD theme 'Climate is changing, food and agriculture must too,' could not have been better chosen.

In response to this theme, and to begin a substantive change process in the Cuban agriculture, FAO and MINAG have organized the Expert Consultation on CA, to be run until Friday, October 21.

  • Published in World

Scientists may have just solved a riddle about Antarctica — and you’re not going to like the answer

It’s one of the great — and unresolved — debates of Antarctic science.

In 1984, a team of researchers from Ohio State University reported on a surprising fossil find: More than a mile above sea level, in Antarctica’s freezing and far inland Transantarctic mountain range, fossilized deposits of tiny marine organisms called diatoms were found in rock layers dated to the Pliocene era, some 2 to 5 million years ago. But how did they get all the way up there? Diatoms, ubiquitous marine microorganisms whose tiny shells coat the ocean floor when they die, don’t show up in high mountain rocks unless something rather dramatic happened long ago to get them there.

So began the debate over this rock formation, dubbed the “Sirius Group” after Mount Sirius, one of the range’s many peaks. It was between the “dynamicists”— who argued that the enormous ice sheet of East Antarctica had dramatically collapsed in the Pliocene, bringing the ocean far closer in to the Transantarctic range, and that subsequent upthrusts of the Earth and re-advances of glaciers had then delivered the diatoms from the seafloor to great heights — and the so-called “stabilists.” To the contrary, these scientists argued, the ice sheet had stayed intact, but powerful winds had swept the diatoms all the way from the distant sea surface into the mountains.

“It became very much split into two camps,” remembers Reed Scherer, an Antarctic researcher at Northern Illinois University. “It got really nasty.” Some researchers even tried to resolve matters by suggesting that a meteorite, and subsequent cataclysms, could account for the odd fossil locations.

But the decades have given way to new research tools and new perspectives. And Scherer has now paired up with two researchers behind what is arguably the hottest (and most troubling) new computer simulation of how Antarctica’s ice behaves in order to revisit the tale of those pesky diatoms. Their solution, published Tuesday in Nature Communications, isn’t good news — for it suggests that large parts of East Antarctica can indeed collapse in conditions not too dissimilar from those we’re creating today with all of our greenhouse gas emissions.

If we steer the Earth back to those Pliocene-type conditions — when sea levels are believed to have been radically higher around the globe — oddly located diatoms will be the least of our problems.

The new study is co-authored by Rob DeConto of the University of Massachusetts, Amherst, and David Pollard of Penn State University, who recently published a new ice sheet model of Antarctica that predicts the ice continent can raise sea levels by nearly a meter on its own during this century. They reached this result by adding several new dynamic ice collapse processes to glacial models that, in the past, had been slow to melt East Antarctica even in quite warm conditions — simultaneously lending weight to the views of the stabilists in the debate over the Sirius fossils, while also seeming to suggest that we needn’t worry about truly radical sea-level rise from Antarctica.

The result is that in the Pliocene — and especially the mid-Pliocene warm period, when atmospheric carbon dioxide was at about the level where it is now, 400 parts per million, but global temperatures were 1 or 2 degrees warmer than at present — the model not only collapses the entirety of West Antarctica (driving some 10 feet of global sea-level rise) but also shows the oceans eating substantially into key parts of East Antarctica. In particular, the multi-kilometer thick ice that currently fills the extremely deep Aurora and Wilkes basins of the eastern ice sheet retreats inland for hundreds of miles — which would have driven global seas to a much higher level than caused by a West Antarctic collapse alone.

Here’s a figure from the study, showing as much:

Not only is this the world we could be headed to if global warming continues, but it’s a world that can throw diatoms up into the Transantarctic Mountains, the new study argues. Here’s how that would work.

At first, in the wake of ice retreats in the Aurora and Wilkes basins, what would be left behind are ocean bays filled with life — and many, many diatoms. But Scherer and his colleagues do not believe that winds simply scooped them out of the water and hurled them to the mountains — living, wet diatoms suspended in water would have been too heavy to travel so far, Scherer says.

So instead, the study postulates another development. After a few thousand years of seas filled with happy diatoms, dying and lining the ocean floor in front of the remnant glaciers of the Wilkes and Aurora basins, the once submerged Earth would slowly rebound in some spots (a process sometimes called “isostatic uplift” or “postglacial rebound”). This would create an archipelago of islands, new landmasses free to rise to the surface now that so much ice has sloughed off their backs.

These islands, then, were the source of the diatoms, the study postulates.

The computer model “did show the ice retreated along the margins of East Antarctica, and isostatic uplift would then expose these areas that become new seaways, and with it would have been highly productive for plankton,” says Scherer. “So you would have been accumulating massive numbers of diatoms across this new basin, and with the loss of the ice, the land flexed upward, became exposed to winds, and the wind carried them to the mountains.”

Scherer notes that his new scenario doesn’t really proclaim either the dynamicists or the stabilists the victors. His view is clearly reliant on a substantial amount of dynamics, but it also doesn’t show the East Antarctica ice retreated nearly as far back as earlier proposals. Nor does it use glacial processes to move the deposited diatoms. Rather, it borrows the stabilist idea of wind-blown transport, albeit only after ice has retreated and land has risen in its wake.

Commenting on this new compromise proposal Monday, one Antarctic researcher praised the work as representing an advance on old ways of thinking. “The paper is a great example of how much [paleo]climate modelling has improved in the last decade[s], particularly in the last few years,” said Simone Galeotti, an Antarctic researcher at the Università degli Studi di Urbino in Italy, by email.

The research also earned praise from David Harwood, one of the original ‘dynamicists’ and now a professor at the University of Nebraska-Lincoln.

“This paper’s integration of climate, ice sheet, and atmospheric models provides interesting new perspective on potential source regions for the Antarctic, marine Pliocene diatoms present in glacial sediments of the Transantarctic Mountains, from interior basins of East Antarctica,” said Harwood in an emailed statement. “Their origin from deglaciated, exposed, rebounded marine basin floors in the Aurora and Wilkes basins is plausible, and the new model-derived wind patterns support their trajectory toward the [Transantarctic Mountains].”

But beyond solving the riddle of the Sirius deposits in the Transantarctic Mountains, the new study speaks to the present moment. After all, the warm Pliocene, with its much higher seas, is one of the key past eras that scientists regularly look to for an analogue for where we are currently driving the planet with our greenhouse gases.

And thus, the new work suggests that if we keep pushing the system, we’ll not only have to worry about the loss of Greenland’s and West Antarctica’s ice, but also major losses from the biggest ice sheet of them all, East Antarctica.

Scherer, DeConto, and Pollard also have a fourth author on the study, the noted Penn State glaciologist Richard Alley, who has become more and more outspoken of late about his concerns that the world’s great ice sheets could be unstable. In a media statement accompanying the study’s release, Alley had this to say:

This is another piece of a jigsaw puzzle that the community is rapidly putting together, and which appears to show that the ice sheets are more sensitive to warming than we had hoped. If humans continue to warm the climate, we are likely to commit to large and perhaps rapid sea-level rise that could be very costly. No one piece of the puzzle shows this, but as they fit together, the picture is becoming clearer.

In other words, solving this key scientific problem from Antarctica’s past turns out to immediately raise major concerns about its future.

“We have now reached a point where atmospheric CO2 levels are as high as that during the Pliocene, 400 ppm, when geological evidence and new model results suggest substantial retreat of the EAIS [East Antarctic Ice Sheet] margin into interior basins. These perspectives bear fundamentally on predictions of future EAIS behavior,” said Harwood by email.

Granted, on a scientific and individual level, there’s also the satisfaction of finally being able to unify quite a lot of information into an explanation that fits the data and also matches our growing present day understanding of Antarctic vulnerability.

“Personally, I find the story rather cathartic, because it does explain the observations, I think, in a much better way than had been done before,” says Scherer.

 

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