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As the IPCC report is predicting "dire consequences" (and is all but ignored by most media), this article reflects more accurately the true situation.
Guy McPherson, Paul McPherson interviewed by Dahr Jamail
The Vanishing Arctic Ice Cap
An Arctic largely devoid of ice, giant methane outbursts causing tsunamis in the North Atlantic, and global sea levels rising by several meters by mid-century sound like the stuff of science fiction.
By Dahr Jamail
31 March, 2014
But to a growing number of scientists studying Anthropogenic Climate Disruption (ACD/climate change), these dramatic predictions are very real possibilities in our not-so-distant future, thanks to the vanishing Arctic ice cap, which is continuing its rapid decrease in both volume and area.
Arctic sea ice researchers are predicting that sea ice will no longer last through summers in the next couple of years, and even US Navy researchers have predicted an ice-free Arctic by 2016. Whichever year the phenomenon begins, it will be the first time humans have existed on Earth without year-round sea ice in the Arctic, and scientists warn that this is when "abrupt climate change" passes the point of no return.
To read more about anthropomorphic climate disruption and how environments and communities suffer from corporate profit-seeking, click here.
"In the first year that this happens, the open Arctic Ocean state will only last for a few weeks to a month or so," Paul Beckwith, a climatology and meteorology professor at the University of Ottawa, Canada, told Truthout. "Within a year or two, the open water duration [no sea ice] will last for several months, and within a decade or so the positive feedbacks will likely clear out the Arctic Ocean basin for most of the year."
Beckwith, an engineer and physicist who is also researching abrupt climate change in both present day and in the paleo records of the deep past, warns that losing the Arctic sea ice will create a state that "will represent a very different planet, with a much higher global average temperature, as much as 5 to 6 degrees C warmer within a few decades, in which snow and ice in the northern hemisphere becomes very rare or even vanishes year round."
The UN Intergovernmental Panel on Climate Change (IPCC), the world's most authoritative voice on climate science, whose reports influence policy and planning decisions of national governments across the world, has just released its latest report. The IPCC has been accused by much of the scientific community of having a starkly conservative bias.
Scientific American has said of the IPCC: "Across two decades and thousands of pages of reports, the world's most authoritative voice on climate science has consistently understated the rate and intensity of climate change and the danger those impacts represent."
However, the recently released IPCC report is raising eyebrows: Even this conservative body is predicting dire threats for people and other species in the near future, and these risks may very well mean "abrupt or drastic changes" that could lead to unstoppable and irreversible climate shifts like the melting of both the Arctic ice cap and Greenland's glacial ice.
According to the IPCC report, the polar bear is not alone in being under threat.
"The polar bear is us," says Patricia Romero Lankao of the federally financed National Center for Atmospheric Research in Boulder, Colorado, referring to the first species to be listed as threatened by global warming due to melting sea ice.
Beckwith, who believes the planet is already in the early stages of abrupt ACD, offered grave predictions of what we might expect from losing the Arctic ice.
"As the planet transitions through this abrupt climate change, there will be wrenching turmoil and conflict for human civilizations," he explained. "As the extreme weather events ramp up this will result in a frenzy of human activity to attempt to adapt and mitigate. Essentially, this tipping point in the Arctic will inevitably result in a tipping point in human response to the problem."
"Critical to the Earth System"
John Nissen is chairman of the Arctic Methane Emergency Group, a collection of scientists and experts whose mission is to warn the global community of the crisis we face if the Arctic ice melts. He studied natural sciences at Cambridge University and now studies ACD full time, with a focus on the role of Arctic sea ice within the Earth climactic system.
"Arctic sea ice is critical to the Earth System because of its role in controlling the planet's temperature, climate and currents," Nissen told Truthout. "Warm currents from the Atlantic and Pacific oceans flow into the Arctic, and are cooled. Extra warming of these currents has resulted in a retreat of the sea ice with loss of albedo [solar reflection] as the sea ice is replaced by open water. The open water absorbs the heat, which accumulates and helps to melt the sea ice the following year in a vicious cycle of warming and melting."
Nissen explained that when the sea ice no longer forms in the summer, there will already have been a great reduction in albedo. Arctic warming, which is already occurring at 1 degree C per decade, will accelerate at a rate of several degrees C per decade from then on.
There is historical precedent for this, as Arctic warming of 7 degrees in one decade occurred at the end of the Younger Dryas, an abrupt climate change event accompanied by many meters of sea-level rise. The Younger Dryas is one of the more commonly used examples of abrupt climate change of cold climatic conditions and drought that occurred between approximately 12,800 and 11,500 years ago. While there are many theories, the event is thought to have been caused by the collapse of the North American ice sheets.
Guy McPherson, professor emeritus of evolutionary biology, natural resources, and ecology at the University of Arizona and a climate change expert of 25 years, explained to Truthout why the Arctic is so critically important to the planetary weather system.
"Arctic ice serves as a planetary air conditioner," McPherson said. "We've never had humans on a planet without Arctic ice, which suggests that the planet is too warm for large-bodied mammals in the absence of the planetary air conditioner."
With an Arctic that is ice-free in the summers, McPherson predicts rapid, dramatic changes.
"Earth will heat up quickly," he said. "Consider, for example, a relatively simple example from the realm of physics. Slightly more than 79 calories are required to convert one gram of ice at 0 C to 1 milliliter of water at 0 C. But once the ice is converted to water, adding the same amount of energy increases the temperature of the water to slightly more than 79 C."
He then goes on to imagine that on the scale of the Arctic Ocean.
"Without any ice in the Arctic to absorb energy, the energy will be absorbed by the dark ocean water," he said. "Even a tiny bit of ice provides a tremendous buffer to runaway heating by the ocean (hence, the planet)."
Heat moves from the warm equator to the cold poles of the Earth via the atmosphere circulation patterns and ocean currents. But due to human emissions of greenhouse gases, the planet system is warming.
In the Arctic, this means the warming is causing the sea ice volume and spring terrestrial snow cover to decline extremely quickly, thus exposing the darker underlying surfaces of ocean water and permafrost on land.
"These darker surfaces absorb more solar energy, and thus there is an amplification of warming of the Arctic at rates five to eight times faster than the overall warming average," Beckwith said. "This decreases the temperature difference between the Arctic and the equator and thus decreases the heat moving from the equator northward, resulting in a slowing of the westward movement of the high-speed winds making up the jet stream. The jet stream becomes wavier and leads to an increase in the frequency, intensity, duration and spatial extent location and variation."
Nissen is seeing the same phenomenon, with the loss of Arctic sea ice already changing the jet stream, which is the weather driver for North America and northern Europe.
"This has led to a decline in the temperature gradient between tropics and Arctic, thus destabilizing the jet stream and mid-latitude weather systems, leading to an increase in extreme weather events, tantamount to abrupt climate change," he said.
The sea ice also plays a role in driving the global conveyor current: As sea ice is formed in the Arctic Ocean, salt is expelled and the old dense saline water falls to the seabed to form a deep-level current that flows to the edge of Antarctica. These thermohaline currents are critically important, as the state of their circulation has a large impact on the Earth's.
Disturbingly, a new study shows that similar currents in the Antarctic may already be slowing down.
The study by the University of Pennsylvania's Irina Marinov and Raffaele Bernardello and colleagues from McGill University found that ACD may be causing the slowdown of one of these conveyer belts, with potentially serious consequences for the future of the planet's climate.
"Our observations are showing us that there is less formation of these deep waters near Antarctica," Marinov said. "This is worrisome because, if this is the case, we're likely going to see less uptake of human produced, or anthropogenic, heat and carbon dioxide by the ocean, making this a positive feedback loop for climate change."
A Rapidly Declining Situation
Professor Peter Wadhams, a leading Arctic expert at Cambridge University, has been measuring Arctic ice for 40 years.
"The fall-off in ice volume is so fast it is going to bring us to zero very quickly," Wadhams told a reporter. According to current data, he estimates "with 95 percent confidence" that the Arctic will have completely ice-free summers by 2018.
Wadhams works with Nissen, and the two presented a paper on their studies at the European Geosciences Union in 2010, warning the conference of the dire consequences of massive methane releases if the Arctic ice continues to melt as it is.
"The seabed," says Wadhams, "is offshore permafrost, but is now warming and melting. We are now seeing great plumes of methane bubbling up in the Siberian Sea … millions of square miles where methane cover is being released."
As Truthout previously reported, and according to a study published in Nature Geoscience last fall, twice as much methane as previously thought is being released from the East Siberian Arctic Shelf, a two million square kilometer area off the coast of Northern Siberia. Its researchers found that at least 17 teragrams (one million tons) of methane are being released into the atmosphere each year, whereas a 2010 study had found only seven teragrams heading into the atmosphere.
"Over hundreds of millennia, Arctic permafrost soils have accumulated vast stores of organic carbon - an estimated 1,400 to 1,850 petagrams of it (a petagram is 2.2 trillion pounds, or 1 billion metric tons). That's about half of all the estimated organic carbon stored in Earth's soils. In comparison, about 350 petagrams of carbon have been emitted from all fossil-fuel combustion and human activities since 1850. Most of this carbon is located in thaw-vulnerable topsoils within 10 feet (3 meters) of the surface."
The NASA study highlights the discovery of active and growing methane vents up to 150 kilometers across. A scientist on a research ship in the area described this as a bubbling as far as the eye can see, in which the seawater looks like a vast pool of seltzer. Between the summers of 2010 and 2011, in fact, scientists found that in the course of a year methane vents only 30 centimeters across had grown a kilometer wide, a 333,333 percent increase and an example of the non-linear rapidity with which parts of the planet are responding to climate disruption.
This information is part of why Nessin made this dire prediction:
"Outbursts of methane from the seabed and/or ice from GIS [Greenland Ice Sheet] are liable to cause tsunamis in the North Atlantic."
He also believes there is a "small probability but high risk of an outburst of many gigatons of methane, sufficient to escalate global warming towards many degrees of temperature rise with intolerable climate change and societal collapse."
Nessin sees the most immediate effect of continuing, unchecked decline in sea ice and acceleration of Arctic warming being an escalation in climate change, as the jet stream and weather systems are further disrupted from their old norms.
"This climate change would inevitably lead to crop failures, a worldwide increase in the price of food, widespread starvation, and conflict through much of Africa and Asia," he warned. "We are seeing the start already, but without intervention the situation could decline rapidly over the next decade."
Beckwith gave similarly ominous warnings of what could be coming.
"There will be attempts to cool the Arctic to keep the methane and carbon dioxide from explosively escaping from the terrestrial permafrost and marine sediments," he said. "In the transitions, many governments will fall and martial law will be implemented in many countries as there is a resource scramble for ever scarcer fresh water and food."
Sealing the Fate of the Planet
Nessin believes the Greenland Ice Sheet ice discharge is liable to continue growing exponentially, with a doubling every five years, causing many meters of sea-level rise by mid century.
"The icebergs and fresh water generated to the west of Greenland are liable to divert the warm currents flowing across the Atlantic, thus partially turning the Atlantic Meridional Overturning Circulation, with a devastating effect on Northern Hemisphere climate," he warned.
Meanwhile, evidence of runaway ACD continues to mount.
"Many of the extreme events of 2013 were consistent with what we would expect as a result of human-induced climate change," Michel Jarraud, the secretary-general of the UN's World Meteorological Organization (WMO), said recently.
The group's recently released annual assessment of global weather found that 2013 was the sixth warmest year on record (tied with 2007), and that there has been no let-up in global warming. Thirteen of the 14 warmest years have occurred since 2000 and each of the last three decades has been warmer than the previous one, with the decade 2001-2010 being the warmest on record, according to the WMO.
"There is no standstill in global warming. The warming of our oceans has accelerated, and at lower depths. More than 90 percent of the excess energy trapped by greenhouse gases is stored in the oceans," Dr Jarraud said of ACD's impact on the oceans. "Levels of these greenhouse gases are at record levels, meaning that our atmosphere and oceans will continue to warm for centuries to come. The laws of physics are non-negotiable."
The WMO report revealed that Arctic sea ice in 2013 had fallen to a level that is the sixth lowest on record. The WMO noted all seven of the lowest Arctic sea-ice extents took place in the past seven years, starting with 2007, which "stunned" scientists at the time.
The depth of the crisis, and ramifications thereof, has led Nissen and his group to controversially advocate the use of geo-engineering techniques to cool the Arctic. Geo-engineering, the deliberate and large-scale intervention in the Earth's climatic system with the aim of reducing global warming, is extremely controversial due to its obvious potential of unintended consequences.
"I see no other way to prevent an inexorable meltdown of the Arctic ice cap with dreadful consequences for all mankind including catastrophic global warming from the methane which would be released," Nissen said. "The simple approach to prevent such catastrophes is to cool the Arctic using geo-engineering techniques such as cloud brightening and stratospheric aerosols."
Nissen believes the greatest risk to human society and the rest of the planet is that if attention is diverted away from the important role of Arctic sea ice, "intervention to cool the Arctic will be too late to prevent complete Arctic meltdown, which would surely lead to a collapse of civilization and a greatly reduced human population. Complete extinction would be in the cards."
McPherson also believes that near-term human extinction could eventually result from losing the Arctic sea ice, and added, "A world without Arctic ice will be completely new to humans."
As to what should be done, however, he disagrees with Nissen and others promoting geo-engineering as a solution.
"Although geo-engineering has been proposed by some people, the literature suggests such attempts are misguided. At the level of society, I doubt there is anything to be done," said McPherson. "Whereas human ingenuity painted us into this corner, I do not believe human ingenuity is capable of providing an escape.
Tim Garrett pointed out in Climatic Change nearly five years ago that only complete collapse of industrial civilization prevents runaway greenhouse. Since Garrett's paper was published, scientific literature has illustrated about 30 self-reinforcing feedback loops with respect to climate change."
Sixty-three percent of all human-generated carbon emissions have been produced in just the last 25 years, but science reveals a 40-year time lag between global emissions (our actions) and climate impacts (the consequences). Hence, we haven't even begun to experience the worst of our emissions, and won't, until 2054.
This information, along with the aforementioned, is what has led McPherson to this grim prognosis:
"The 40-year lag between emissions of greenhouse gases and consequent rise in global-average temperature suggests our planetary fate was sealed decades ago."
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