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Climate Change Worse Than We Thought, Likely To Be ‘Catastrophic Rather Than Simply Dangerous’

“Climate change may be far worse than scientists thought, causing global temperatures to rise by at least 4 degrees Celsius by 2100, or about 7.2 degrees Fahrenheit, according to a new study.

The study, published in the journal Nature, takes a fresh look at clouds’ effect on the planet, according to a report by The Guardian. The research found that as the planet heats, fewer sunlight-reflecting clouds form, causing temperatures to rise further in an upward spiral.

That number is double what many governments agree is the threshold for dangerous warming. Aside from dramatic environmental shifts like melting sea ice, many of the ills of the modern world — starvation, poverty, war and disease — are likely to get worse as the planet warms.

“4C would likely be catastrophic rather than simply dangerous,” lead researcher Steven Sherwood told the Guardian. “For example, it would make life difficult, if not impossible, in much of the tropics, and would guarantee the eventual melting of the Greenland ice sheet and some of the Antarctic ice sheet.”

Another report released earlier this month said the abrupt changes caused by rapid warming should be cause for concern, as many of climate change’s biggest threats are those we aren’t ready for.”

Study predicts imminent irreversible planetary ecosystem collapse

“In Approaching a state-shift in Earth’s biosphere, a paper just published in Nature, the authors, whose expertise span a multitude of disciplines, suggest our planet’s ecosystems are careening towards an imminent, irreversible collapse. Earth’s accelerating loss of biodiversity, its climates’ increasingly extreme fluctuations, its ecosystems’ growing connectedness and its radically changing total energy budget are precursors to reaching a planetary state threshold or tipping point. Once that happens, which the authors predict could be reached this century, the planet’s ecosystems, as we know them, could irreversibly collapse in the proverbial blink of an eye. “The last tipping point in Earth’s history occurred about 12,000 years ago when the planet went from being in the age of glaciers, which previously lasted 100,000 years, to being in its current interglacial state. Once that tipping point was reached, the most extreme biological changes leading to our current state occurred within only 1,000 years. That’s like going from a baby to an adult state in less than a year,” explains Arne Mooers. “Importantly, the planet is changing even faster now.”

The SFU professor of biodiversity is one of this paper’s authors. He stresses, “The odds are very high that the next global state change will be extremely disruptive to our civilizations. Remember, we went from being hunter-gathers to being moon-walkers during one of the most stable and benign periods in all of Earth’s history. “Once a threshold-induced planetary state shift occurs, there’s no going back. So, if a system switches to a new state because you’ve added lots of energy, even if you take out the new energy, it won’t revert back to the old system. The planet doesn’t have any memory of the old state.” These projections contradict the popularly held belief that the extent to which human-induced pressures, such as climate change, are destroying our planet is still debatable, and any collapse would be both gradual and centuries away. This study concludes we better not exceed the 50 per cent mark of wholesale transformation of Earth’s surface or we won’t be able to delay, never mind avert, a planetary collapse.”

Methane Releases from Arctic Shelf May Trigger Drastic Climate Changes

It’s from 2010, but read it again:

Methane Releases from Arctic Shelf May Trigger Drastic Climate Changes

Science stunner: Vast East Siberian Arctic Shelf methane stores destabilizing and venting

March 4, 2010 – Original Source: Climate Progress

NSF issues world a wake-up call: “Release of even a fraction of the methane stored in the shelf could trigger abrupt climate warming”

Methane release from the not-so-perma-frost is the most dangerous amplifying feedback in the entire carbon cycle.  Research published in Friday’s journal Science finds a key “lid” on “the large sub-sea permafrost carbon reservoir” near Eastern Siberia “is clearly perforated, and sedimentary CH4 [methane] is escaping to the atmosphere.”

Scientists learned last year that the permafrost permamelt contains a staggering “1.5 trillion tons of frozen carbon, about twice as much carbon as contained in the atmosphere,” much of which would be released as methane.  Methane is  is 25 times as potent a heat-trapping gas as CO2 over a 100 year time horizon, but 72 times as potent over 20 years!

The carbon is locked in a freezer in the part of the planet warming up the fastest (see “Tundra 4: Permafrost loss linked to Arctic sea ice loss“).  Half the land-based permafrost would vanish by mid-century on our current emissions path (see “Tundra, Part 2: The point of no return” and below).  No climate model currently incorporates the amplifying feedback from methane released by a defrosting tundra.

The new Science study, led by University of Alaska’s International Arctic Research Centre and the Russian Academy of Sciences, is “Extensive Methane Venting to the Atmosphere from Sediments of the East Siberian Arctic Shelf” (subs. req’d).  The must-read National Science Foundation press release (click here), warns “Release of even a fraction of the methane stored in the shelf could trigger abrupt climate warming.”  The NSF is normally a very staid organization.  If they are worried, everybody should be.

It is increasingly clear that if the world strays significantly above 450 ppm atmospheric concentrations of carbon dioxide for any length of time, we will find it unimaginably difficult to stop short of 800 to 1000 ppm.

Note:  As part of the Climate Science Project, I’m making this post as definitive as I can by including other recent scientific findings on the tundra.  Please add other relevant links in the comments.

The lead author, Natalia Shakhova, explains the new findings in this video:

NSF explains:

“The amount of methane currently coming out of the East Siberian Arctic Shelf is comparable to the amount coming out of the entire world’s oceans,” said Shakhova, a researcher at UAF’s International Arctic Research Center. “Subsea permafrost is losing its ability to be an impermeable cap.”

Methane is a greenhouse gas more than 30 times more potent than carbon dioxide. It is released from previously frozen soils in two ways. When the organic material (which contains carbon) stored in permafrost thaws, it begins to decompose and, under anaerobic conditions, gradually releases methane. Methane can also be stored in the seabed as methane gas or methane hydrates and then released as subsea permafrost thaws. These releases can be larger and more abrupt than those that result from decomposition.

The East Siberian Arctic Shelf is a methane-rich area that encompasses more than 2 million square kilometers of seafloor in the Arctic Ocean. It is more than three times as large as the nearby Siberian wetlands, which have been considered the primary Northern Hemisphere source of atmospheric methane. Shakhova’s research results show that the East Siberian Arctic Shelf is already a significant methane source, releasing 7 teragrams of methane yearly, which is as much as is emitted from the rest of the ocean. A teragram is equal to about 1.1 million tons.

“Our concern is that the subsea permafrost has been showing signs of destabilization already,” she said. “If it further destabilizes, the methane emissions may not be teragrams, it would be significantly larger.”

Shakhova notes that the Earth’s geological record indicates that atmospheric methane concentrations have varied between about .3 to .4 parts per million during cold periods to .6 to .7 parts per million during warm periods. Current average methane concentrations in the Arctic average about 1.85 parts per million, the highest in 400,000 years, she said. Concentrations above the East Siberian Arctic Shelf are even higher.

The East Siberian Arctic Shelf is a relative frontier in methane studies. The shelf is shallow, 50 meters (164 feet) or less in depth, which means it has been alternately submerged or terrestrial, depending on sea levels throughout Earth’s history. During the Earth’s coldest periods, it is a frozen arctic coastal plain, and does not release methane. As the Earth warms and sea level rises, it is inundated with seawater, which is 12-15 degrees warmer than the average air temperature.

“It was thought that seawater kept the East Siberian Arctic Shelf permafrost frozen,” Shakhova said. “Nobody considered this huge area.”

Last August I discussed findings by German and British scientists “that more than 250 plumes of bubbles of methane gas are rising from the seabed of the West Spitsbergen continental margin in the Arctic, in a depth range of 150 to 400 metres” (see “So many amplifying methane feedbacks, so little time to stop them all” and figure on right).

A lead researcher of that work said, “Our survey was designed to work out how much methane might be released by future ocean warming; we did not expect to discover such strong evidence that this process has already started.”

But the situation in the ESAS is far, far more dicey, as NSF explains:

The East Siberian Arctic Shelf, in addition to holding large stores of frozen methane, is more of a concern because it is so shallow. In deep water, methane gas oxidizes into carbon dioxide before it reaches the surface. In the shallows of the East Siberian Arctic Shelf, methane simply doesn’t have enough time to oxidize, which means more of it escapes into the atmosphere. That, combined with the sheer amount of methane in the region, could add a previously uncalculated variable to climate models.

“The release to the atmosphere of only one percent of the methane assumed to be stored in shallow hydrate deposits might alter the current atmospheric burden of methane up to 3 to 4 times,” Shakhova said. “The climatic consequences of this are hard to predict.”

And we also know that a key trigger for accelerated warming in the Arctic region is the loss of sea ice.

A 2008 study by leading tundra experts found “Accelerated Arctic land warming and permafrost degradation during rapid sea ice loss.” The lead author is David Lawrence of the National Center for Atmospheric Research (NCAR), whom I interviewed for my book and interviewed again via e-mail in 2008. The study’s ominous conclusion:

We find that simulated western Arctic land warming trends during rapid sea ice loss are 3.5 times greater than secular 21st century climate-change trends. The accelerated warming signal penetrates up to 1500 km inland….

In other words, a continuation of the recent trend in sea ice loss may triple Arctic warming, causing large emissions in carbon dioxide and methane from the tundra this century.

Oh, and the Arctic warming could lead to another feedback according to a 2008 Science article:  “Continuation of current trends in shrub and tree expansion could further amplify this atmospheric heating 2-7 times.”  The point is that if you convert a white landscape to a boreal forest, the surface suddenly starts collecting a lot more solar energy (see “Tundra 3: Forests and fires foster feedbacks“).

That trend is occurring now, as seen in these two photos from a recent ScienceNews article, “Boreal forests shift north.”

“Upper photo taken in 1962 shows tundra-dominated mountain slope in Siberian Urals. A 2004 photo of the same site, below, shows conifers were setting up dense stand of forest.”

Another major study warns that the warming-driven northward march of vegetation poses yet another threat to the tundra:  “Greater fire activity will likely accompany temperature-related increases in shrub-dominated tundra predicted for the 21st century and beyond.”  The concern is not so much the direct emissions from burning tundra, but the albedo change.

And all that warming would cause massive melting of the tundra and faster emissions release. That must be avoided at all cost, since the tundra feedback, coupled with the climate-carbon-cycle feedbacks that the IPCC models, could easily take us to the unmitigated catastrophe of 1000 ppm.

The good news is that a 2009 NOAA-led study found “Near-zero CH4 growth in the Arctic during 2008 suggests we have not yet activated strong climate feedbacks from permafrost and CH4 hydrates” (see “Is it just too damn late?“)

The bad news is we clearly are on very thin ice.  Literally.

Lawrence revised and updated his 2005 analysis of tundra loss under different emissions scenarios (after some scientists criticized the original work) in this 2008 study, “Sensitivity of a model projection of near-surface permafrost degradation to soil column depth and representation of soil organic matter” (subs. req’d).  The updated analysis still found: “the warming is enough to drive near-surface permafrost extent sharply down by 2100.”

I had asked Lawrence if it was still reasonable to keep using this figure in my presentation, since it is so much easier to understand than the figures in his new paper.

He said, “Using the old figure is still fine as long as one mentions the caveats that permafrost is probably degrading a bit too rapidly in the original.

So I will certainly use that caveat, though, of course, I will also caveat the caveat by saying the slightly slower rate of permafrost degradation does not include Lawrence’s new analysis on the accelerated warming of the permafrost due to sea ice loss (or, for that matter, the accelerated warming of the permafrost due to faster shrub encroachment).

Note that the “B1″ scenario stabilizes CO2 concentrations in the air at 550 ppm — and the near-surface permafrost permafrost (down to 11 feet) plummets from over 4 million square miles today to 1.5 million.  If concentrations hit 850 ppm in 2100 (A2), permafrost would shrink to just 800,000 square miles.

And while these projections were done with one of the world’s most sophisticated climate system models, the calculations do not include the feedback effect of the released carbon from the permafrost. That is to say, the CO2 concentrations in the model rise only as a result of direct emissions from humans, with no extra emissions counted from soils or tundra. Thus they are conservative numbers–or overestimates–of how much CO2 concentrations have to rise to trigger irreversible melting.

In short, the would-be point of atmospheric stabilization, 550 ppm isn’t stable at all — it is past the point of no return. We must stay well below 450 ppm to save the tundra and hence the climate.  The new research underscores that conclusion, especially since the planet will keep warming (slowly) for decades even once we slash emissions to near zero.

And that means we must begin a staggering amount of clean energy deployment as soon as possible (see “How the world can (and will) stabilize at 350 to 450 ppm: The full global warming solution“).

Wake up media and politicians who are being duped by the anti-science disinformers into thinking there is any serious doubt about the catastrophe we face on our current path of unrestricted emissions!

UPDATE:  WWF’s Nick Sundt points out:

A report released by the U.S. Global Change Research Program, Abrupt Climate Change, said in December 2008 (during the Bush Administration) that warming in the Arctic could cause sea levels to rise substantially beyond scientists’ previous predictions and could result in massive releases of methane.  The report said that the “rapid release to the atmosphere of methane trapped in permafrost and on continental margins” was among “four types of abrupt change in the paleoclimatic record that stand out as being so rapid and large in their impact that if they were to recur, they would pose clear risks to society in terms of our ability to adapt.”

The NSF has a good fact sheet, “Questions and Answers on Potentially Large Methane Releases From Arctic, and Climate Change.”

UPDATE:  Since we don’t have a time series of CH4 emissions from the shelf, we can’t know for certain that these emissions levels are new or growing.  But as the study makes clear, they are unexpectedly high and the lid is perforated:

They found that more than 80 percent of the deep water and more than 50 percent of surface water had methane levels more than eight times that of normal seawater. In some areas, the saturation levels reached more than 250 times that of background levels in the summer and 1,400 times higher in the winter. They found corresponding results in the air directly above the ocean surface. Methane levels were elevated overall and the seascape was dotted with more than 100 hotspots. This, combined with winter expedition results that found methane gas trapped under and in the sea ice, showed the team that the methane was not only being dissolved in the water, it was bubbling out into the atmosphere.

These findings were further confirmed when Shakhova and her colleagues sampled methane levels at higher elevations. Methane levels throughout the Arctic are usually 8 to 10 percent higher than the global baseline. When they flew over the shelf, they found methane at levels another 5 to 10 percent higher than the already elevated Arctic levels.

So yes, there is the possibility this is a grand coincidence — but  that would not eliminate the fact that the  lid  on these vast methane stores is perforated and emissions are poised to rise  sharply as temperature rises and none of this is in any of the global climate models.  How much is  the business as usual warming now projected for the region?  Try M.I.T. doubles its 2095 warming projection to 10°F — with 866 ppm and Arctic warming of 20°F.

The nations of the world should immediately begin emergency methane monitoring across the entire permafrost region — and, of course, aggressive GHG mitigation.  The risk of abrupt climate change is simply too grave to not treat as the most serious preventable problem now facing the human race as a whole.

Climate ‘tipping points’ may arrive without warning

February 10 2010 – Original Source: Zeenews

Washington: In a new study, a top ecological forecaster has said that climate ‘tipping points’ that can cause an irreparable global disaster may arrive without any warning as such.

The study, carried out by Alan Hastings from University of California, Davis, indicated that it is harder than experts thought to predict when sudden shifts in Earth’s natural systems will occur.

“Many scientists are looking for the warning signs that herald sudden changes in natural systems, in hopes of forestalling those changes, or improving our preparations for them,” said Hastings.

“Our new study found, unfortunately, that regime shifts with potentially large consequences can happen without warning — systems can ‘tip’ precipitously,” he said.

“This means that some effects of global climate change on ecosystems can be seen only once the effects are dramatic. By that point returning the system to a desirable state will be difficult, if not impossible,” he added.

The current study focuses on models from ecology, but its findings may be applicable to other complex systems, especially ones involving human dynamics such as harvesting of fish stocks or financial markets.

Scientists widely agree that global climate change is already causing major environmental effects, such as changes in the frequency and intensity of precipitation, droughts, heat waves and wildfires; rising sea level; water shortages in arid regions; new and larger pest outbreaks afflicting crops and forests; and expanding ranges for tropical pathogens that cause human illness.

They fear that worse is in store.

As US presidential science adviser John Holdren recently told a congressional committee, “Climate scientists worry about ‘tipping points’ … thresholds beyond which a small additional increase in average temperature or some associated climate variable results in major changes to the affected system.”

Among the tipping points Holdren listed were: the complete disappearance of Arctic sea ice in summer, leading to drastic changes in ocean circulation and climate patterns across the whole Northern Hemisphere; acceleration of ice loss from the Greenland and Antarctic ice sheets, driving rates of sea-level increase to 6 feet or more per century; and ocean acidification from carbon dioxide absorption, causing massive disruption in ocean food webs.

Long-Term Cooling Trend in Arctic Abruptly Reverses, Signaling Potential for Sea Rise

September 3, 2009 – Original Source: University of Colorado at Boulder

A new study led by Northern Arizona University and involving the University of Colorado at Boulder indicates Arctic temperatures have reversed from a long-term cooling trend and are now the warmest they have been in at least 2,000 years, bad news for the world’s coastal cities facing rising seas in the coming decades.

High northern latitudes have experienced a long-term, slow cooling trend for several millennia, the result of a wobble in Earth’s rotation that has been increasing the distance between the sun and Earth and decreasing Arctic summer sunshine. The research team assembled high-resolution records of climate for the past 2,000 years and found that the cooling trend reversed in the 20th century.

The decade from 1999 to 2008 was the warmest in the last 200 decades and corresponds with a continuing buildup of human-generated greenhouse gases in Earth’s atmosphere, said lead author Darrell Kaufman of Northern Arizona University. “Scientists have known for a while that the current period of warming was preceded by a long-term cooling trend, said Kaufman. “But our reconstruction quantifies the cooling with greater certainty than ever before.”

Since the Earth is still moving away from the sun — it’s about 0.6 million miles farther during the Northern Hemisphere summer solstice than it was in 1 B.C. — it appears greenhouse gases began “overriding” the natural cooling of Earth in the middle of the last century, said Professor Gifford Miller of CU-Boulder’s Institute for Arctic and Alpine Research, a study co-author. “We expect the Arctic will continue to warm in the coming decades, increasing land-based ice loss and triggering global increases in sea-level rise,” he said.

The study was published in the Sept. 4 issue of Science. Other institutions participating in the study included the National Center for Atmospheric Research in Boulder, the University of Arizona, the University of Massachusetts, the University of East Anglia in Norwich, England, and the University of Copenhagen in Denmark. The study was funded by the National Science Foundation.

The research team reconstructed past temperatures on a decade-by-decade basis during the past 2,000 years using information gleaned from ancient lake sediments, ice cores, tree rings and other samples. As part of the study, the decade-by-decade climate data reconstruction was compared with sophisticated climate model simulations run by NCAR researchers.

The NCAR climate simulations agreed closely with the ground-based Arctic data used in the study, said NCAR scientist David Schneider, a co-author on the study. “This result is particularly important because the Arctic, perhaps more than any other region on Earth, is facing dramatic impacts from climate change,” Schneider said. “This study provides us with a long-term record that reveals how greenhouse gases from human activities are overwhelming the Arctic’s natural climate system.”

The new Science study dovetails with a report published earlier this year by the U.S. Climate Change Science Program on changes in the Arctic and at high latitudes. The CCSP study’s five lead authors — including Miller and CU-Boulder INSTAAR Director Jim White — concluded climate warming in the Arctic and at high latitudes likely will continue at a rapid pace given human-caused changes in Earth’s atmosphere.

Arctic temperatures have reached their highest level in the past decade, averaging 2.5 degrees Fahrenheit higher than would have been expected if the 2,000-year cooling trend had continued through the latter part of the 20th century and into the 21st century, said Kaufman. Kaufman received his doctorate from CU-Boulder in 1991 while studying under Miller at INSTAAR.

Previous research has shown that Arctic temperatures increased three times faster during the 20th century than temperatures in the rest of the Northern Hemisphere — a phenomenon known as “Arctic amplification,” said Miller, also a professor of geological sciences at CU-Boulder. The amplification is caused by decreased Arctic sea ice and an increased absorption of the sun’s heat by exposed ocean as well as “darker” land areas caused by decreases of Arctic snow and ice, he said.

“With less sea ice in winter, the ocean returns the heat stored in summer to the atmosphere, resulting in warmer winters throughout the Arctic,” said Miller.

“Because we know that the processes responsible for past Arctic amplification are still operating, we can anticipate that it will continue into the next century,” said Miller. “The magnitude of change was surprising, and reinforces the conclusion that humans are significantly altering Earth’s climate.”

“As we are confronted with evidence of global warming, it is extremely helpful to be able to use paleoclimate data to provide context for today’s climate relative to the range and trajectory of recent climate regimes,” said Neil Swanberg, director of NSF’s Arctic System Science Program.

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