Updated most recently, likely for the final time, 2 August 2016.
Self-Reinforcing Feedback Loops (also see analysis here)
1. This description combines sub-sea permafrost and methane hydrates in the Arctic. The two sources of methane are sufficiently similar to warrant considering them in combination. MSNBC knew about methane release from beneath the Arctic Ocean in 2007. Oddly, they seem to be ignorant about it today. And note that award-winning journalist Dahr Jamail’s reporting about methane registered at spot #6 on Project Censored’s 2014 compilation.
About 250 plumes of methane hydrates are escaping from the shallow Arctic seabed, likely as a result of a regional 1 C rise in temperature, as reported in the 6 August 2009 issue of Geophysical Research Letters. Methane bubbling out the Arctic Ocean is further elucidated in Science in March 2010. As described in a subsequent paper in the June 2010 issue of Geophysical Research Letters, a minor increase in temperature would cause the release of upwards of 16,000 metric tons of methane each year. Storms accelerate the release, according to research published in the 24 November 2013 issue of Nature Geoscience The latter paper also concludes the East Siberian Arctic Shelf is venting at least 17 teragrams of the methane into the atmosphere each year, up from 0.5 teragrams just 7 years earlier (a teragram is equal to 1 million tons). According to NASA’s CARVE project, these plumes were up to 150 kilometers across as of mid-July 2013. Global-average temperature is expected to rise by more than 4 C by 2030 and 10 C by 2040 based solely on methane release from the Arctic Ocean, according to Sam Carana’s research (see especially Image 24). Whereas Malcolm Light’s 9 February 2012 forecast of extinction of all life on Earth by the middle of this century appeared premature because his conclusion of exponential methane release during summer 2011 was based on data subsequently revised and smoothed by U.S. government agencies, subsequent information — most notably from NASA’s CARVE project — indicates the grave potential for catastrophic release of methane. (I doubt industrial civilization manages to kill all life on Earth, although that clearly is the goal.) Catastrophically rapid release of methane in the Arctic is further supported by Nafeez Ahmed’s thorough analysis in the 5 August 2013 issue of the Guardian as well as Natalia Shakhova’s 29 July 2013 interview with Nick Breeze (note the look of abject despair at the eight-minute mark). The 16 August 2013 issue of Geophysical Research Letters includes a report of the Siberian Kara Sea where “Arctic shelf region where seafloor gas release is widespread suggests that permafrost has degraded more significantly than previously thought.” In early November 2013, methane levels well in excess of 2,600 ppb were recorded at multiple altitudes in the Arctic. Later that same month, Shakhova and colleagues published a paper in Nature Geoscience suggesting “significant quantities of methane are escaping the East Siberian Shelf” and indicating that a 50-billion-tonne “burst” of methane could warm Earth by 1.3 C. Such a burst of methane is “highly possible at any time,” according to Shakhova in July 2013, which echoes findings from 2008 (paradoxically, on 23 May 2015 Shakhova said, “We never stated that 50 gigatonnes is likely to be released in near or distant future”). In the 7 September 2015 issue of Philosophical Transactions of the Royal Society A, Shakhova and colleagues concluded that “progression of subsea permafrost thawing and decrease in ice extent could result in a significant increase in CH4 emissions from the ESAS” (East Siberian Arctic Shelf).In the 7 September 2015 issue of Philosophical Transactions of the Royal Society A, Shakhova and colleagues concluded that “progression of subsea permafrost thawing and decrease in ice extent could result in a significant increase in CH4 emissions from the ESAS” (East Siberian Arctic Shelf). Taking an expectedly more conservative approach, Peter Wadhams expects a 0.6 C rise in global-average temperature within five years after an ice-free Arctic, more than sufficient to collapse civilization and enough to make Wadhams ponder human extinction.
By 15 December 2013, methane bubbling up from the seafloor of the Arctic Ocean had sufficient force to prevent sea ice from forming in the area. Nearly two years after his initial, oft-disparaged analysis, Malcolm Light concluded on 22 December 2013, “we have passed the methane hydrate tipping point and are now accelerating into extinction as the methane hydrate ‘Clathrate Gun’ has begun firing volleys of methane into the Arctic atmosphere.” According to Light’s analysis in late 2013, the temperature of Earth’s atmosphere will resemble that of Venus before 2100. The refereed journal literature tackles the topic of hothouse Earth with a paper in the 9 February 2016 issue of Nature Communications: “Water-rich planets such as Earth are expected to become eventually uninhabitable, because liquid water turns unstable at the surface as temperatures increase with solar luminosity. Whether a large increase of atmospheric concentrations of greenhouse gases such as CO2 could also destroy the habitability of water-rich planets has remained unclear. Here we show with three-dimensional aqua-planet simulations that CO2-induced forcing as readily destabilizes the climate as does solar forcing. The climate instability is caused by a positive cloud feedback and leads to a new steady state with global-mean sea-surface temperatures above 330 K” (330 Kelvin is about 57 C, compared to today’s temperature of about 15 C). Two weeks after Light’s 2013 analysis, in an essay stressing near-term human extinction, Light concluded: “The Gulf Stream transport rate started the methane hydrate (clathrate) gun firing in the Arctic in 2007 when its energy/year exceeded 10 million times the amount of energy/year necessary to dissociate subsea Arctic methane hydrates.” The refereed journal literature, typically playing catch-up with reality, includes an article in the 3 February 2014 issue of Journal of Geophysical Research: Earth Surface claiming, “Sustained submergence [of these sediments] into the future should increase gas venting rate roughly exponentially as sediments continue to warm.” Not surprisingly, the clathrate gun began firing in 2007, the same year the extent of Arctic sea ice reached a tipping point. Abundant evidence supporting the firing of the clathrate gun was collated and presented here on 9 September 2012. Further confirmation the clathrate gun had been fired came from Stockholm University’s Örjan Gustafsson, who reported from the Laptev Sea on 23 July 2014: “results of preliminary analyses of seawater samples pointed towards levels of dissolved methane 10-50 times higher than background levels.” Jason Box responds to the news in the conservative fashion I’ve come to expect from academic scientists on 27 July 2014: “What’s the take home message, if you ask me? Because elevated atmospheric carbon from fossil fuel burning is the trigger mechanism poking the climate dragon. The trajectory we’re on is to awaken a runaway climate heating that will ravage global agricultural systems leading to mass famine, conflict. Sea level rise will be a small problem by comparison.” Later, during an interview with Vice published 1 August 2014, Box loosened up a bit, saying, “Even if a small fraction of the Arctic carbon were released to the atmosphere, we’re fucked.” Trust me, Jason, we’re there.
Simultaneous with the Laptev Sea mission, several large holes were discovered in Siberia. The reaction from an article published in the 31 July 2014 issue of Nature indicates atmospheric methane levels more than 50,000 times the usual. An article in the 4 August 2014 edition of Ecowatch ponders the holes: “If you have ever wondered whether you might see the end of the world as we know it in your lifetime, you probably should not read this story, nor study the graphs, nor look at the pictures of methane blowholes aka dragon burps.”
One of the authors of two research papers rooted in the Siberian Kara Sea concluded on 22 December 2014, “If the temperature of the oceans increases by two degrees as suggested by some reports, it will accelerate the thawing to the extreme. A warming climate could lead to an explosive gas release from the shallow areas.” As we’ve known for a few years, 2 C is locked in.
By late February 2015, the Siberian crater saga had become “more widespread — and scarier — than anyone thought,” with numerous reports from the mainstream media. Naturally, these reports focused on economic impacts and the need for further research.
Methane release from thawing offshore permafrost was further verified with research reported in the 7 August 2015 issue of Journal of Geophysical Research. This paper, for the first time, describes pingo-like features beneath the seabed offshore from Siberia.
According to researchers quoted in the 22 September 2015 issue of The Siberian Times, the rare media outlet that is willing to address abrupt climate change in a meaningful manner, those massive craters on the Yamal Peninsula are, in fact, created by the release of methane. Furthermore, more craters are expected due to eruptions as permafrost continues to melt.
It turns out those giant, methane-emitting craters in the Yamal region of Siberia have subsea counterparts. A paper in the 7 August 2015 issue of Journal of Geophysical Research: Earth Science connects the craters on land with those in the adjacent, shallow South Kara Sea. According a write-up in The Siberian Times: “Large mounds — described as pingos — have been identified on the seabed off the Yamal Peninsula, and their formation is seen as due to the thawing of subsea permafrost, causing a ‘high accumulation’ of methane gas.”
The importance of methane cannot be overstated. Increasingly, evidence points to a methane burst underlying the Great Dying associated with the end-Permian extinction event, as pointed out in the 31 March 2014 issue of Proceedings of the National Academy of Sciences. As Malcolm Light reported on 14 July 2014: “There are such massive reserves of methane in the subsea Arctic methane hydrates, that if only a few percent of them are released, they will lead to a jump in the average temperature of the Earth’s atmosphere of 10 degrees C and produce a ‘Permian’ style major extinction event which will kill us all. Apparently a 5 C rise in global-average temperature was responsible for the Great Dying, according to Michael Benton’s book on the topic. In that case, the rise is temperature requires tens of thousands of years.
Discussion about methane release from the Arctic Ocean has been quite heated (pun intended). Paul Beckwith was criticized by the conservative website, Skeptical Science. His response from 9 August 2013 is here.
Robert Scribbler provides a terrifying summary 24 February 2014, and concludes, “two particularly large and troubling ocean to atmosphere methane outbursts were observed” in the Arctic Ocean. Such an event hasn’t occurred during the last 45 million years. Scribbler’s bottom line: “that time of dangerous and explosive reawakening, increasingly, seems to be now.”
Sam Carana includes the figure below in his 10 September 2014 analysis. Based on data from several reputable sources, exponential release of methane clearly is under way. Robert Scribbler reaches the conclusion, finally, on 8 December 2014.
A paper published in the 22 December 2015 online issue of the Proceedings of the National Academy of Sciences reports, “that emissions during the cold season (September to May) contribute ≥50% of annual sources of methane from Alaskan tundra, based on fluxes obtained from eddy covariance sites and from regional fluxes calculated from aircraft data. … The dominance of late season emissions, sensitivity to soil conditions, and importance of dry tundra are not currently simulated in most global climate models.”
2. Warm Atlantic water is defrosting the Arctic as it shoots through the Fram Strait (Science, January 2011). Extent of Arctic sea ice passed a tipping point in 2007, according to research published in the February 2013 issue of The Cryosphere. On 6 October 2012, Truth-out cites Peter Wadhams, professor of ocean physics at Cambridge University: “The Arctic may be ice-free in summer as soon as 2015. Such a massive loss would have a warming effect roughly equivalent to all human activity to date. In other words, a summer ice-free Arctic could double the rate of warming of the planet as a whole.” Subsequent melting of Arctic ice is reducing albedo, hence enhancing absorption of solar energy. According to NASA on 17 December 2014, “the rate of absorbed solar radiation in the Arctic in June, July and August has increased by five percent” since 2000. “Averaged globally, this albedo change is equivalent to 25% of the direct forcing from CO2 during the past 30 years,” according to research published in the 17 February 2014 issue of the Proceedings of the National Academy of Sciences. Destabilization of the deep circulation in the Atlantic Ocean may be “spasmodic and abrupt rather than a more gradual increase” as earlier expected, according to a paper published in the 21 February 2014 issues of Science. Models continue to underestimate results relative to observations, as reported in the 10 March 2014 issue of Geophysical Research Letters. Consider, for example, the thinning “by more than 50 metres since 2012 — about one sixth of its original thickness — and that it is now flowing 25 times faster,” as reported in the 23 December 2014 issue of Geophysical Research Letters. Rapid ice melt in the region is explained as a product of warm-air advection, air mass transformation, and fog in the June 2015 issue of Geophysical Research Letters.
3. Peat in the world’s boreal forests is decomposing at an astonishing rate (Nature Communications, November 2011)
4. Ozone, a powerful greenhouse gas, also contributes to mortality of trees (Global Change Biology, November 2011). Tree mortality reduces uptake of atmospheric carbon dioxide and instead accelerates the contribution of carbon dioxide into the atmosphere. Forest dieback resulting from atmospheric ozone is the primary topic addressed by Gail Zawacki at Wit’s End.
Analysis of tropospheric data has linked elevated levels of ozone with Indonesian forest fires, according to a paper in the 13 January 2016 issue of Nature Communications. Like methane, ozone is a potent but short-lived greenhouse gas. As indicated in the abstract: “This study suggest a larger role for biomass burning in the radiative forcing of climate in the remote TWP (Tropical Western Pacific) than is commonly appreciated.”
5. Invasion of tall shrubs warms the soil, hence destabilizes the permafrost (Environmental Research Letters, March 2012). Further elucidation of this phenomenon included study of 25 species, and ~42,000 annual growth records from 1,821 individuals, as reported in the 6 July 2015 online issue of Nature Climate Change.
6. Greenland ice is darkening (The Cryosphere, June 2012). As reported in the 8 June 2014 issue of Nature Geoscience, “a decrease in the albedo of fresh snow by 0.01 leads to a surface mass loss of 27 Gt” annually. Any reduction in albedo is a disaster, says Peter Wadhams, head of the Polar Oceans Physics Group at Cambridge University. As pointed out by Robert Scribbler on 1 August 2014, we’ve removed the plug and, like the water leaving a tub, acceleration is under way: “Extensive darkening of the ice sheet surface, especially near the ice sheet edge, is resulting in more solar energy being absorbed by the ice sheet. Recent studies have shown that edge melt results in rapid destabilization and speeds glacier flows due to the fact that edge ice traditionally acts like a wall holding the more central and denser ice pack back.” Jason Box registers his surprise with a photo essay on 29 October 2014. A paper in the 15 December 2014 issue of Proceedings of the National Academy of Sciences provides the first comprehensive picture of how Greenland’s ice is vanishing and concludes “that Greenland may lose ice more rapidly in the near future than previously thought.” Research reported in the 17 December 2015 issue of Nature calculates spatial ice mass loss around the entire Greenland Ice Sheet from 1900 to the present and finds “that many areas currently undergoing change are identical to those that experienced considerable thinning throughout the twentieth century.” According to one of paper’s co-authors “the average mass loss rate over the past decade is much larger than at any other time over the last 115 years.”
Adding to the rapidity of ice melt on Greenland is cloud cover. A paper published in the 12 January 2016 edition of Nature Communications shows that clouds are playing a larger role than previously understood in heating the Greenland Ice Sheet. Clouds trap heat, thus accounting for as much as 30% of the ongoing melt of the ice sheet.
According to a paper in the 3 March 2016 issue of The Cryosphere, the darkening of the Greenland ice sheet started becoming significantly less reflective of solar radiation from around 1996, with the ice absorbing 2% more solar energy per decade from this point. “Future darkening is likely underestimated,” according to the paper’s abstract.
7. Methane is being released from beneath Antarctic ice, too (Nature, August 2012). This third primary source of methane — in addition to permafrost and the shallow seabed — potentially is enormous. According to a paper in the 24 July 2013 issue of Scientific Reports, melt rate in the Antarctic has caught up to the Arctic and the West Antarctic Ice Sheet is losing over 150 cubic kilometres of ice each year according to CryoSat observations published 11 December 2013, and Antarctica’s crumbling Larsen-B Ice Shelf is poised to finish its collapse, according to Ted Scambos, a glaciologist at the National Snow and Ice Data Center at the annual meeting of the American Geophysical Union. A paper in the 12 September 2014 issue of Science concluded the major collapse of the Larsen-B Ice Shelf in 2002 resulted from warm local air temperatures, indicating the importance of global and local warming on ice dynamics. Two days later a paper in Nature Climate Change indicates that this sensitivity to temperature illustrates “that future increases in precipitation are unlikely to offset atmospheric-warming-induced melt of peripheral Antarctic Peninsula glaciers.” A study published in the 1 June 2015 issue of Earth and Planetary Science Letters finds the last remaining section of Antarctica’s Larsen B Ice Shelf, which partially collapsed in 2002, is quickly weakening and is likely to disintegrate completely before the end of the decade. Meanwhile, the Larsen-C Ice Shelf is poised to collapse, according to an article in the 13 May 2015 issue of The Cryosphere. A paper in the 8 February 2016 online issue of Nature Climate Change reinforces prior findings about the collapse of major ice shelves in Antarctica. Some of these country-sized, so-called “safety bands” are extremely dynamic and therefore susceptible to rapid breakup. The rate of loss during the period 2010-2013 was double that during the period 2005-2010, according to a paper in the 16 June 2014 issue of Geophysical Research Letters. By mid-May 2015 the sudden onset of ice loss in Antarctica was large enough to affect Earth’s gravity field, as reported in the 21 May 2015 issue of Science. According to NASA climate scientist Eric Rignot in early 2015, “the fuse is blown.” Rignot goes on to explain this “shattering” moment and also points out the utter ineptitude by climate scientists at explaining the situation to the public. According to research reported in the 26 March 2015 issue of Science, “West Antarctic losses increased by 70% in the last decade, and earlier volume gain by East Antarctic ice shelves ceased.” Loss of Antarctic ice is accelerating even in areas long considered stable, as documented in the 24 July 2013 edition of Scientific Reports. Based on gravity data published in the 1 April 2015 issue of Earth and Planetary Science Letters: “During the past decade, Antarctica’s massive ice sheet lost twice the amount of ice in its western portion compared with what it accumulated in the east, according to Princeton University researchers who came to one overall conclusion — the southern continent’s ice cap is melting ever faster.” The faster-than-expected narrative continued into 10 July 2015, when a paper in Science Advances found that geothermal activity was contributing to rapid melting of the West Antarctic Ice Sheet. The 14 March 2016 issue of Nature Geoscience includes a paper about Antarctic ice shelves concluding that “loss of ice shelf mass is accelerating, especially in West Antarctica, where warm seawater is reaching ocean cavities beneath ice shelves. … We conclude that basal channels can form and grow quickly as a result of warm ocean water intrusion, and that they can structurally weaken ice shelves, potentially leading to rapid ice shelf loss in some areas.” According to a paper in the 20 June 2016 issue of Nature Communications: “Here we report the discovery of a massive subsurface ice layer, at least 16 km across, several kilometres long and tens of metres deep, located in an area of intense melting and intermittent ponding on Larsen C Ice Shelf, Antarctica. We combine borehole optical televiewer logging and radar measurements with remote sensing and firn modelling to investigate the layer, found to be ~10 °C warmer and ~170 kg m−3 denser than anticipated in the absence of ponding and hitherto used in models of ice-shelf fracture and flow.” ** The Antarctic Peninsula is one of the fastest warming spots on the planet, and it was thought that the rising air temperature was driving the melt of the glaciers along its fringes. But it is actually warm ocean waters that are eating away at the ice along part of its western side, a group of scientists reported 15 July 2016 in the journal Science. ** Further confirmation of large methane releases is revealed by noctilucent clouds over the southern hemisphere from 21 November 2013 to 6 December 2013.
It’s not just Antarctica spewing methane hydrates from beneath the ice. Ice sheets may be hiding vast reservoirs in the Arctic, too, as reported in the 7 January 2016 issue of Nature Communications. As reported in the abstract, “recent dating of methane expulsion sites suggests that gas release has been ongoing over many millennia. Here we synthesize observations of ~1,900 fluid escape features — pockmarks and active gas flares — across a previously glaciated Arctic margin with ice-sheet thermomechanical and gas hydrate stability zone modelling. Our results indicate that even under conservative estimates of ice thickness with temperate subglacial conditions, a 500-m thick gas hydrate stability zone — which could serve as a methane sink — existed beneath the ice sheet. Moreover, we reveal that in water depths 150–520 m methane release also persisted through a 20-km-wide window between the subsea and subglacial gas hydrate stability zone. This window expanded in response to post-glacial climate warming and deglaciation thereby opening the Arctic shelf for methane release.”
8. Forest and bog fires are growing (in Russia, initially, according to NASA in August 2012), a phenomenon consequently apparent throughout the northern hemisphere (Nature Communications, July 2013). The New York Times reports hotter, drier conditions leading to huge fires in western North America as the “new normal” in their 1 July 2013 issue. A paper in the 22 July 2013 issue of the Proceedings of the National Academy of Sciences indicates boreal forests are burning at a rate exceeding that of the last 10,000 years. Los Alamos National Laboratory catches on during same month. According to reports from Canada’s Interagency Fire Center, total acres burned to date in early summer 2014 are more than six times that of a typical year. This rate of burning is unprecedented not just for this century, but for any period in Canada’s basement forest record over the last 10,000 years. A comprehensive assessment of biomass burning, published in the 21 July 2014 issue of Journal of Geophysical Research: Atmospheres, explains most of the global-average increase in temperature and explains that biomass burning causes much more global warming per unit weight than other human-associated carbon sources. By early August 2014 tundra fires were burning just 70 miles south of Arctic Ocean waters and the fires were creating their own weather via pyrocumulus clouds. According to a paper published in the 14 July 2015 issue of Nature Communications, the length of the fire season has increased nearly 20% since 1979.
Ignition sources are on the rise, too. According to a paper in the 14 November 2014 issue of Science, each 1 C rise in global-average temperature contributes to a 12 ± 5% increase in lightning strikes.
According to a paper in the 6 October 2015 online issue of the Proceedings of the National Academy of Sciences comes a paper describing how the 0.5 C rise in global-average temperature associated with the Medieval Climate Anomaly — commonly called the Medieval Warm period — contributed to substantial increase in area burned. According to the abstract: “Warming of ∼0.5 °C ∼1,000 years ago increased the percentage of our study sites burned per century by ∼260% relative to the past ∼400 y.”
According to a paper in the 16 March 2016 issue of Global Ecology and Biogeography, climate change is adversely altering the ability of Rocky Mountain forests to recover from wildfire. Specifically, warm, dry conditions in the years following fires impede the growth and establishment of vulnerable new post-fire seedlings. Not only does climate change contribute to more and larger fires in the region, thus killing the trees in the forest, but post-fire recruitment is reduced by the same conditions that contribute to the more and larger fires.
9. Cracking of glaciers accelerates in the presence of increased carbon dioxide (Journal of Physics D: Applied Physics, October 2012)
10. The Beaufort Gyre apparently has reversed course (U.S. National Snow and Ice Data Center, October 2012). Mechanics of this process are explained by the Woods Hole Oceanographic Institution here.
11. Exposure to sunlight increases bacterial conversion of exposed soil carbon, thus accelerating thawing of the permafrost (Proceedings of the National Academy of Sciences, February 2013). Subsequent carbon release “could be expected to more than double overall net C losses from tundra to the atmosphere,” as reported in the March 2014 issue of Ecology. Arctic permafrost houses about half the carbon stored in Earth’s soils, an estimated 1,400 to 1,850 petagrams of it, according to NASA, which is more than twice as much as already exists in the atmosphere. Peat chemistry changes as warming proceeds, which accelerates the process, as reported in the 7 April 2014 issue of Proceedings of the National Academy of Sciences.
12. The microbes have joined the party, too, according to a paper in the 23 February 2013 issue of New Scientist. A subsequent paper in the 22 October 2014 issue of Nature illustrates the key role of a single species of microbe in amplifying climate change.
13. According to a paper in the 12 April 2013 issue of Science, a major methane release is almost inevitable from permafrost in Alaska, which makes me wonder where the authors have been hiding. Almost inevitable, they report, regarding an ongoing event. Trees are tipping over and dying as permafrost thaws, thus illustrating how self-reinforcing feedback loops feed each other. A paper in the 6 April 2015 online issue of Nature concludes: “The heat production is not only expected to accelerate the organic carbon decomposition and potentially the amounts of carbon emitted to the atmosphere but could be the tipping point that will lead to the loss of evidence of early human history in the Arctic, which so far has been extremely well preserved in the top permafrost.” The rapidly decaying permafrost is largely recent in origin, according to a paper in the 27 April 2015 issue of Geophysical Research Letters, and is leading to a “runaway effect.” The resulting carbon is entering “the atmosphere at breakneck speed,” according to an analysis published in the 27 April 2015 issue of Geophysical Research Letters. A paper in the 1 February 2016 issue of the Journal of Geophysical Research: Biogeosciences finally indicates the scientific literature is catching up to the reality of the dire situation: “our results suggest that this subarctic tundra ecosystem is shifting away from its historical function as a C sink to a C source.” Slowly catching up to reality, a paper in the 12 March 2016 issue of Climate Change Responses indicates “the large stocks of carbon stored in graminoid soils should be more susceptible to mineralization in a warming Arctic.” In other words, climate warming accelerates carbon release from thawing Arctic soils.
A paper in the 20 June 2016 issue of Environmental Research Letters. According to the paper, permafrost thaw has risen fourfold in some Arctic regions during the last 50 years.
14. Summer ice melt in Antarctica is at its highest level in a thousand years: Summer ice in the Antarctic is melting 10 times quicker than it was 600 years ago, with the most rapid melt occurring in the last 50 years (Nature Geoscience, April 2013). According to a paper in the 4 March 2014 issue of Geophysical Research Letters — which assumes relatively little change in regional temperature during the coming decades — “modeled summer sea-ice concentrations decreased by 56% by 2050 and 78% by 2100” (Robert Scribbler’s in-depth analysis is here). Citing forthcoming papers in Science and Geophysical Research Letters, the 12 May 2014 issue of the New York Times reported: “A large section of the mighty West Antarctica ice sheet has begun falling apart and its continued melting now appears to be unstoppable. … The new finding appears to be the fulfillment of a prediction made in 1978 by an eminent glaciologist, John H. Mercer of the Ohio State University. He outlined the vulnerable nature of the West Antarctic ice sheet and warned that the rapid human-driven release of greenhouse gases posed ‘a threat of disaster.'” Although scientists have long expressed concern about the instability of the West Antarctic Ice Sheet (WAIS), a research paper published in the 28 August 2013 of Nature indicates the East Antarctic Ice Sheet (EAIS) has undergone rapid changes in the past five decades. The latter is the world’s largest ice sheet and was previously thought to be at little risk from climate change. But it has undergone rapid changes in the past five decades, signaling a potential threat to global sea levels. The EAIS holds enough water to raise sea levels more than 50 meters. According to a paper in the July 2014 issue of the same journal, the southern hemisphere’s westerly winds have been strengthening and shifting poleward since the 1950s, thus quickening the melt rate to the point of — you guessed it — “results that shocked the researchers.” A paper presented at the late 2014 meeting of the American Geophysical Union concludes, “comprehensive, 21-year analysis of the fastest-melting region of Antarctica has found that the melt rate of glaciers there has tripled during the last decade.” The 16 March 2015 online issue of Nature Geoscience adds to the misery and identifies melting from below Totten Glacier. Specifically, a paper published in the 19 May 2016 issue of Nature finds the Totten Glacier capable of “repeated large-scale retreat and advance,” with the researchers concluding the glacier is “fundamentally unstable.”
A paper in the 12 October 2015 issue of Nature Geoscience reports that the Antarctic ice is melting so fast that the stability of the whole continent could be at risk by 2100. No surprise about that long-into-the-future date, of course. But the paper uses two emissions scenarios to predict a doubling of surface melting of the ice shelves by 2050 and, with one emissions scenario, Antarctic ice shelves would be in danger of collapse by century’s end.
According to a paper in the 2 November 2015 online issue of the Proceedings of the National Academy of Sciences, “if the Amundsen Sea sector is destabilized, then the entire marine ice sheet will discharge into the ocean.” This appears to be admission of “self-sustained ice discharge from West Antarctica.”
According to a paper published in the 26 November 2015 issue of Nature Communications, “Outlet glaciers grounded on a bed that deepens inland and extends below sea level are potentially vulnerable to ‘marine ice sheet instability’. This instability, which may lead to runaway ice loss, has been simulated in models, but its consequences have not been directly observed in geological records. Here we provide new surface-exposure ages from an outlet of the East Antarctic Ice Sheet that reveal rapid glacier thinning occurred approximately 7,000 years ago, in the absence of large environmental changes. Glacier thinning persisted for more than two and a half centuries, resulting in hundreds of metres of ice loss.”
15. Increased temperature and aridity in the southwestern interior of North America facilitates movement of dust from low-elevation deserts to high-elevation snowpack, thus accelerating snowmelt, as reported in the 17 May 2013 issue of Hydrology and Earth System Sciences.
16. Floods in Canada are sending pulses of silty water out through the Mackenzie Delta and into the Beaufort Sea, thus painting brown a wide section of the Arctic Ocean near the Mackenzie Delta brown (NASA, June 2013). Pictures of this phenomenon are shown on this NASA website.
17. Surface meltwater draining through cracks in an ice sheet can warm the sheet from the inside, softening the ice and letting it flow faster, according to a study accepted for publication in the Journal of Geophysical Research: Earth Surface (July 2013). Further support for this idea was reported in the 29 September 2014 issue of Nature Communications. It appears a Heinrich Event has been triggered in Greenland. Consider the description of such an event as provided by Robert Scribbler on 8 August 2013:
In a Heinrich Event, the melt forces eventually reach a tipping point. The warmer water has greatly softened the ice sheet. Floods of water flow out beneath the ice. Ice ponds grow into great lakes that may spill out both over top of the ice and underneath it. Large ice damns (sic) may or may not start to form. All through this time ice motion and melt is accelerating. Finally, a major tipping point is reached and in a single large event or ongoing series of such events, a massive surge of water and ice flush outward as the ice sheet enters an entirely chaotic state. Tsunamis of melt water rush out bearing their vast floatillas (sic) of ice burgs (sic), greatly contributing to sea level rise. And that’s when the weather really starts to get nasty. In the case of Greenland, the firing line for such events is the entire North Atlantic and, ultimately the Northern Hemisphere.
Based on data collected in 2011, a paper published online in the 13 July 2015 issue of Nature Geoscience finds: “Given that the advection of warm, moist air masses and rainfall over Greenland is expected to become more frequent in the coming decades, our findings portend a previously unforeseen vulnerability of the Greenland ice sheet to climate change.” Briefly, melting of the “Greenland ice sheet has been shown to accelerate in response to surface rainfall and melt associated with late-summer and autumnal cyclonic weather events.”
18. Breakdown of the thermohaline conveyor belt is happening in the Antarctic as well as the Arctic, thus leading to melting of Antarctic permafrost (Scientific Reports, July 2013). In the past 60 years, the ocean surface offshore Antarctica became less salty as a result of melting glaciers and more precipitation, as reported in the 2 March 2014 issue of Nature Climate Change.
19. Loss of Arctic sea ice is reducing the temperature gradient between the poles and the equator, thus causing the jet stream to slow and meander (see particularly the work of Jennifer Francis, as well as this article in the 20 November 2014 issue of the Washington Post). The most extreme “dipole” on record occurred during 2013-2014, as reported in the Geophysical Research Letters. One result is the creation of weather blocks such as the recent very high temperatures in Alaska. This so-called “polar vortex” became widely reported in the United States in 2013 and received the attention of the academic community when the 2013-2014 drought threatened crop production in California. Extreme weather events are occurring, as reported in the 22 June 2014 issue of Nature Climate Change. Also called Rossby Waves, these atmospheric events are on the rise, as reported in the 11 August 2014 edition of the Proceedings of the National Academy of Science. A paper co-authored by Francis in the 6 January 2015 issue of Environmental Research Letters concludes with this line in the abstract: “These results suggest that as the Arctic continues to warm faster than elsewhere in response to rising greenhouse-gas concentrations, the frequency of extreme weather events caused by persistent jet-stream patterns will increase.” Regarding the Rossby Waves, a paper in the 24 April 2015 edition of Journal of Geophysical Research: Atmospheres includes this comment: “We also found a positive feedback mechanism resulting from the anomalous meridional circulation that cools the mid-latitudes and warms the Arctic, which adds an extra heating to the Arctic air column equivalent to about 60% of the direct surface heat release from the sea-ice reduction.” Francis’ work was further validated in the 31 August 2015 online issue of Nature Geoscience in an article titled, “Two distinct influences of Arctic warming on cold winters over North America and East Asia.”
As one result of the polar vortex, boreal peat dries and catches fire like a coal seam (also see this paper in Nature, published online 23 December 2014, indicating “the amount of carbon stored in peats exceeds that stored in vegetation and is similar in size to the current atmospheric carbon pool”). The resulting soot enters the atmosphere to fall again, coating the ice surface elsewhere, thus reducing albedo and hastening the melting of ice. Each of these individual phenomena has been reported, albeit rarely, but to my knowledge the dots have not been connected beyond this space. The inability or unwillingness of the media to connect two dots is not surprising, and has been routinely reported (recently including here with respect to climate change and wildfires) (July 2013)
20. Arctic ice is growing darker, hence less reflective (Nature Climate Change, August 2013)
21. Extreme weather events drive climate change, as reported in the 15 August 2013 issue of Nature (Nature, August 2013). Details are elucidated via modeling in the 6 June 2014 issue of Global Biogeochemical Cycles. Further data and explanation are presented in the 27 April 2015 online issue of Nature Climate Change.
“Explaining Extreme Events of 2014 from a Climate Perspective” was published by the Bulletin of the American Meteorological Society in their December 2015 issue and draws on conclusions from 32 international teams of scientists who investigated 28 separate weather events. Findings of this report, released on 5 November 2015, include the following: “Human activities, such as greenhouse gas emissions and land use, influenced specific extreme weather and climate events in 2014, including tropical cyclones in the central Pacific, heavy rainfall in Europe, drought in East Africa, and stifling heat waves in Australia, Asia, and South America.”
According to a paper in the 13 June 2016 issue of the Proceedings of the National Academy of Sciences, atmospheric aerosols strengthen storm clouds, thus leading to extreme weather. An abundance of aerosol particles in the atmosphere — constantly added via industrial activity — can increase the lifespans of large storm clouds by delaying rainfall, making the clouds grow larger and live longer, and producing more extreme storms.
For many years, scientists have cautioned that individual weather events couldn’t be attributed to climate change. Now, however, specific extreme weather events can be attributed to climate change. A 200-page, March 2016 report from the National Academies of Science, Engineering, and Medicine examines the current state of science of extreme weather attribution, and identifies ways to move the science forward to improve attribution capabilities.
22. Drought-induced mortality of trees contributes to increased decomposition of carbon dioxide into the atmosphere and decreased sequestration of atmospheric carbon dioxide. Such mortality has been documented throughout the world since at least November 2000 in Nature, with recent summaries in the February 2013 issue of Nature for the tropics, the August 2013 issue of Frontiers in Plant Science for temperate North America, and the 21 August 2015 issue of Science for boreal forests. The situation is exacerbated by pests and disease, as trees stressed by altered environmental conditions become increasingly susceptible to agents such as bark beetles and mistletoe (additional examples abound).
One extremely important example of this phenomenon is occurring in the Amazon, where drought in 2010 led to the release of more carbon than the United States that year (Science, February 2011). The calculation badly underestimates the carbon release. In addition, ongoing deforestation in the region is driving declines in precipitation at a rate much faster than long thought, as reported in the 19 July 2013 issue of Geophysical Research Letters. An overview of the phenomenon, focused on the Amazon, was provided by Climate News Network on 5 March 2014. “The observed decline of the Amazon sink diverges markedly from the recent increase in terrestrial carbon uptake at the global scale, and is contrary to expectations based on models,” according to a paper in the 19 March 2015 issue of Nature. ** Finally, according to a paper in the 1 July 2016 issue of Global Biogeochemical Cycles, the 2010 drought completely shut down the Amazon Basin’s carbon sink, by killing trees and slowing their growth. **
Tropical rain forests, long believed to represent the primary driver of atmospheric carbon dioxide, are on the verge of giving up that role. According to a 21 May 2014 paper published in Nature, “the higher turnover rates of carbon pools in semi-arid biomes are an increasingly important driver of global carbon cycle inter-annual variability,” indicating the emerging role of drylands in controlling environmental conditions. “Because of the deforestation of tropical rainforests in Brazil, significantly more carbon has been lost than was previously assumed.” In fact, “forest fragmentation results in up to a fifth more carbon dioxide being emitted by the vegetation.” These results come from the 7 October 2014 issue of Nature Communications. A paper in the 28 December 2015 online issue of the Proceedings of the National Academy of Sciences indicates Amazon forest could transition to savanna-like states in response to climate change. Savannas are simply described as grasslands with scattered trees or shrubs. The abstract of the paper suggests that, “in contrast to existing predictions of either stability or catastrophic biomass loss, the Amazon forest’s response to a drying regional climate is likely to be an immediate, graded, heterogeneous transition from high-biomass moist forests to transitional dry forests and woody savannah-like states.”
The boreal forest wraps around the globe at the top of the Northern Hemisphere. It is the planet’s single largest biome and makes up 30 percent of the globe’s forest cover. Moose are the largest ungulate in the boreal forest and their numbers have plummeted. The reason is unknown.
Increasing drought threatens almost all forests in the United States, according to a paper in the 21 February 2016 online issue of Global Change Biology. According to the paper’s abstract, “diebacks, changes in composition and structure, and shifting range limits are widely observed.”
For the first time scientists have investigated the net balance of the three major greenhouse gases — carbon dioxide, methane, and nitrous oxide — for every region of Earth’s land masses. The results were published in the 10 March 2016 issue of Nature. The surprising result: Human-induced emissions of methane and nitrous oxide from ecosystems overwhelmingly surpass the ability of the land to soak up carbon dioxide emissions, which makes the terrestrial biosphere a contributor to climate change.
An abstract of a paper to be published in the April 2016 issue of Biogeochemistry includes these sentences: “Rising temperatures and nitrogen (N) deposition, both aspects of global environmental change, are proposed to alter soil organic matter (SOM) biogeochemistry. … Overall, this study shows that the decomposition and accumulation of molecularly distinct SOM components occurs with soil warming and N amendment and may subsequently alter soil biogeochemical cycling.” In other words, as global temperatures rise, the organic matter in forests appears to break down more quickly, thereby accelerating the release of carbon into the atmosphere.
23. Ocean acidification leads to release of less dimethyl sulphide (DMS) by plankton. DMS shields Earth from radiation. (Nature Climate Change, online 25 August 2013). Plankton form the base of the marine food web, some populations have declined 40% since 1950 (e.g., article in the 29 July 2010 issue of Nature), and they are on the verge of disappearing completely, according to a paper in the 18 October 2013 issue of Global Change Biology. As with carbon dioxide, ocean acidification is occurring rapidly, according to a paper in the 26 March 2014 issue of Global Biogeochemical Cycles. Acidification is proceeding at a pace unparalleled during the last 300 million years, according to research published in the 2 March 2012 issue of Science. Over the past 10 years, the Atlantic Ocean has soaked up 50 percent more carbon dioxide than it did the decade before, measurably speeding up the acidification of the ocean, according to a paper published in the 30 January 2016 issue of Global Biogeochemical Cycles. Not surprisingly, the degradation of the base of the marine food web is reducing the ability of fish populations to reproduce and replenish themselves across the globe, as reported in the 14 December 2015 online edition of the Proceedings of the National Academy of Sciences.
Diatoms, one of the major groups of plankton, is declining globally at the rate of about one percent per year, according to a paper in the 23 September 2015 issue of Global Biogeochemical Cycles.
The Southern Ocean is acidifying at such a rate because of rising carbon dioxide emissions that large regions may be inhospitable for key organisms in the food chain to survive as soon as 2030, according to a paper in the 2 November 2015 online issue of Nature Climate Change.
A paper in the 26 November 2015 issue of Science Express indicates millennial-scale shifts in plankton in the subtropical North Pacific Ocean that are “unprecedented in the last millennium.” The ongoing shift “began in the industrial era and is supported by increasing N2-fixing cyanobacterial production. This picoplankton community shift may provide a negative feedback to rising atmospheric CO2.” One of the authors of the papers is quoted during an interview: “This picoplankton community shift may have provided a negative feedback to rising atmospheric carbon dioxide, during the last 100 years. However, we cannot expect this to be the case in the future.”
Further research on primary productivity in the ocean was published in paper in the 19 January 2016 issue of Geophysical Research Letters. Referring to the Indian Ocean, the abstract concludes, “future climate projections suggest that the Indian Ocean will continue to warm, driving this productive region into an ecological desert.”
For the first time, researchers have documented algae-related toxins in Arctic sea mammals. Specifically, toxins produced by harmful algal blooms are showing up in Alaska marine mammals as far north as the Arctic Ocean — much farther north than ever reported previously, according to a paper in the 11 February 2016 issue of Harmful Algae. The abstract indicates, “In this study, 905 marine mammals from 13 species were sampled including; humpback whales, bowhead whales, beluga whales, harbor porpoises, northern fur seals, Steller sea lions, harbor seals, ringed seals, bearded seals, spotted seals, ribbon seals, Pacific walruses, and northern sea otters. Domoic acid was detected in all 13 species examined and had the greatest prevalence in bowhead whales (68%) and harbor seals (67%). Saxitoxin was detected in 10 of the 13 species … These results provide evidence that … toxins are present throughout Alaska waters at levels high enough to be detected in marine mammals and have the potential to impact marine mammal health in the Arctic marine environment.”
24. Jellyfish have assumed a primary role in the oceans of the world (26 September 2013 issue of the New York Times Review of Books, in a review of Lisa-ann Gershwin’s book, Stung! On Jellyfish Blooms and the Future of the Ocean): “We are creating a world more like the late Precambrian than the late 1800s — a world where jellyfish ruled the seas and organisms with shells didn’t exist. We are creating a world where we humans may soon be unable to survive, or want to.” Jellyfish contribute to climate change via (1) release of carbon-rich feces and mucus used by bacteria for respiration, thereby converting bacteria into carbon dioxide factories and (2) consumption of vast numbers of copepods and other plankton.
25. Sea-level rise causes slope collapse, tsunamis, and release of methane, as reported in the September 2013 issue of Geology. In eastern Siberia, the speed of coastal erosion has nearly doubled during the last four decades as the permafrost melts. And it appears sea-level rise has gone exponential, judging from Scribbler’s 4 May 2015 analysis. Considering only data through 2005, according to a paper published 28 September 2015 in the Proceedings of the National Academy of Sciences, the 500-year return time of floods in New York City has been reduced to 24.4 years.
26. Rising ocean temperatures will upset natural cycles of carbon dioxide, nitrogen and phosphorus, hence reducing plankton (Nature Climate Change, September 2013). Ocean warming has been profoundly underestimated since the 1970s according to a paper published in the online version of Nature Climate Change on 5 October 2014. Specifically, the upper 2,300 feet of the Southern Hemisphere’s oceans may have warmed twice as quickly after 1970 than had previously been thought. According to a 22 January 2015 article in The Guardian, “the oceans are warming so fast, they keep breaking scientists’ charts.”
Another indication of a warming ocean is coral bleaching. The third global coral bleaching event since 1998, and also the third in evidence, ever, is underway on Australia’s Great Barrier Reef. According to Australia National News on 28 March 2016, a survey of the Great Barrier Reef reports 95% of the northern reefs were rated as severely bleached, and only 4 of 520 reefs surveyed were found to be unaffected by bleaching.
27. Earthquakes trigger methane release, and consequent warming of the planet triggers earthquakes, as reported by Sam Carana at the Arctic Methane Emergency Group (October 2013)
28. Small ponds in the Canadian Arctic are releasing far more methane than expected based on their aerial cover (PLoS ONE, November 2013). This is the first of several freshwater ecosystems releasing methane into the atmosphere, as reviewed in the 19 March 2014 issue of Nature and subsequently described by a large-scale study in the 28 April 2014 issue of Global Change Biology. Release of methane from these sources in the Arctic and Greenland, according to the 20 May 2012 issue of Nature Geoscience, “imply that in a warming climate, disintegration of permafrost, glaciers and parts of the polar ice sheets could facilitate the transient expulsion of 14C-depleted methane trapped by the cryosphere cap.”
The mechanism underlying methane release in these systems is poorly understood. If sunlight drives the process, as suggested by a paper in the 22 August 2014 issue of Science, then amplification is expected over time as ponds and lakes are increasingly exposed.
Water bodies within Africa’s interior are adding significantly to the overall release of greenhouse gases into the atmosphere, according to a paper in the 20 July 2015 online edition of Nature Geoscience. Specifically, “total carbon dioxide-equivalent greenhouse-gas emissions [are] … about 0.9 Pg carbon per year, equivalent to about one quarter of the global ocean and terrestrial combined carbon sink.”
Large water bodies beneath deserts could profoundly worsen the situation. According to a paper published in the 28 July 2015 issue of Geophysical Research Letters, a large carbon sink or pool lies beneath the Tarim basin in Xinjiang, China. The hidden pool of water stores “more carbon than all the plants on the planet put together. While more water may sound like a good thing, researchers believe that if this carbon were to escape into the atmosphere, we would be in serious, serious trouble.” Specifically, the senior authored explained in an interview: “It’s like a can of coke. If it is opened all the greenhouse gas will escape into the atmosphere.”
A paper in the 29 October 2015 issue of Limnology and Oceanography also addresses the issue of methane release from lakes. A write-up for the general public titled, “Global Warming Will Progress Much More Quickly Than Expected, Study Predicts” includes this line: “The findings suggest we have a ‘vicious circle’ ahead of us in which the burning of fossil fuels leads to higher temperatures, which in turn trigger higher levels of methane release and further warming.” This is a fine explanation for a self-reinforcing feedback loop.
A study published in the 17 November 2015 edition of Nature Geoscience shows that lakes in the northern hemisphere will probably release much more carbon dioxide due to global climate changes. The investigation, based on data from more than 5,000 Swedish lakes, demonstrates that carbon dioxide emissions from the world’s lakes, water courses, and reservoirs are equivalent to almost a quarter of all the carbon dioxide produced by burning fossil fuels.
Citing two recent journal articles, a paper in the 19 November 2015 issue of Yale Environment 360 concludes, “the world’s iconic northern lakes are undergoing major changes that include swiftly warming waters, diminished ice cover, and outbreaks of harmful algae.” The lakes include Lake Baikal, “the deepest, largest in volume, and most ancient freshwater lake in the world, holding one-fifth of the planet’s above-ground drinking supply. It’s a Noah’s Ark of biodiversity, home to myriad species found nowhere else on earth.”
Further support for the importance of streams and rivers as sources of atmospheric methane comes from a paper published in the November 2015 issue of Ecological Monographs. The headline of the write-up for the general public tells the story: “Greenhouse gas emissions from freshwater higher than thought.”
A paper in the 23 November 2015 issue of Journal of Geophysical Research: Biogeosciences found, according to the abstract: “A sediment upwelling at the end of the thaw season likely contributed to these [methane] emissions. We suggest that, unlike wetlands, shallow seasonally ice-covered lakes can have their highest methane emission potential in the cold season, likely dominating the spring methane release of subarctic landscapes with high lake coverage.” In other words, as with methane release from the Arctic Ocean, methane release is abundant during the cold season. According to a paper in the 16 June 2016 online issue of Geophysical Research Letters, “Our findings indicate that permafrost below shallow lakes has already begun crossing a critical thawing threshold approximately 70 years prior to predicted terrestrial permafrost thaw in northern Alaska.”
A paper in the 4 January 2016 online edition of Nature Geoscience finds, “lakes and ponds are a dominant methane source at high northern latitudes.” “By compiling previously reported measurements made at a total of 700 northern water bodies the researchers have been able to more accurately estimate emissions over large scales. They found that methane emissions from lakes and ponds alone are equivalent to roughly two-thirds of all natural methane sources in the northern region.”
According to a paper in the 1 February 2016 issue of Nature Geoscience, ponds less than a quarter of an acre in size make up only 8.6% of the surface area of the world’s lakes and ponds, yet they account for 15.1% of carbon dioxide emissions and 40.6% of diffusive methane emissions.
29. Mixing of the jet stream is a catalyst, too. High methane releases follow fracturing of the jet stream, accounting for a previous rise in regional temperature up to 16 C in less than 20 years (Paul Beckwith via video on 19 December 2013).
30. Research indicates that “fewer clouds form as the planet warms, meaning less sunlight is reflected back into space, driving temperatures up further still” (Nature, January 2014)
31. “Thawing permafrost promotes microbial degradation of cryo-sequestered and new carbon leading to the biogenic production of methane” (Nature Communications, February 2014). According to a paper in the 21 October 2015 issue of the Proceedings of the National Academy of Sciences,: “The observed DOC [dissolved organic carbon] loss rates are among the highest reported for permafrost carbon and demonstrate the potential importance of LMW [low–molecular-weight] DOC in driving the rapid metabolism of Pleistocene-age permafrost carbon upon thaw and the outgassing of CO2 to the atmosphere by soils and nearby inland waters.”
32. Over the tropical West Pacific there is a natural, invisible hole extending over several thousand kilometers in a layer that prevents transport of most of the natural and man-made substances into the stratosphere by virtue of its chemical composition. Like in a giant elevator, many chemical compounds emitted at the ground pass thus unfiltered through this so-called “detergent layer” of the atmosphere. Global methane emissions from wetlands are currently about 165 teragrams (megatons metric) each year. This research estimates that annual emissions from these sources will increase by between 17 and 260 megatons annually. By comparison, the total annual methane emission from all sources (including the human addition) is about 600 megatons each year. (Nature Geoscience, February 2014)
33. “Volcanologist Bill McGuire describes how rapid melting of glaciers and ice sheets as a result of climate change could trigger volcanoes, earthquakes, and tsunamis” (13 February 2014 issue of The Guardian. According to a paper published online in the 5 February 2015 issue of Geophysical Research Letters, “underwater volcanoes defy expectations and erupt in bursts rather than a slow pace.”
34. Deep ocean currents apparently are slowing. According to one of the authors of the paper, “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.” Because this phenomenon contributed to cooling and sinking of the Weddell polynya: “it’s always possible that the giant polynya will manage to reappear in the next century. If it does, it will release decades-worth of heat and carbon from the deep ocean to the atmosphere in a pulse of warming.” (Nature Climate Change, February 2014; model results indicate “large spatial redistribution of ocean carbon,” as reported in the March 2014 issue of the Journal of Climate)
35. Increased atmospheric carbon dioxide causes soil microbes to produce more carbon dioxide (Science, 2 May 2014)
36. Reductions in seasonal ice cover in the Arctic “result in larger waves, which in turn provide a mechanism to break up sea ice and accelerate ice retreat” (Geophysical Research Letters, 5 May 2014). Further corroboration is found in the 27 March 2015 issue of Geophysical Research Letters.
37. A huge hidden network of frozen methane and methane gas, along with dozens of spectacular flares firing up from the seabed, has been detected off the North Island of New Zealand (preliminary results reported in the 12 May 2014 issue of the New Zealand Herald). The first evidence of widespread active methane seepage in the Southern Ocean, off the sub-Antarctic island of South Georgia, was subsequently reported in the 1 October 2014 issue of Earth and Planetary Science Letters.
38. As reported in the 8 June 2014 issue of Nature Geoscience, rising global temperatures could increase the amount of carbon dioxide naturally released by the world’s oceans, fueling further climate change
39. As global-average temperature increases, “the concentrations of water vapor in the troposphere will also increase in response to that warming. This moistening of the atmosphere, in turn, absorbs more heat and further raises the Earth’s temperature.” As reported in the paper’s abstract: “Our analysis demonstrates that the upper-tropospheric moistening observed over the period 1979–2005 cannot be explained by natural causes and results principally from an anthropogenic warming of the climate. By attributing the observed increase directly to human activities, this study verifies the presence of the largest known feedback mechanism for amplifying anthropogenic climate change.” (Proceedings of the National Academy of Sciences, 12 August 2014) According to a July 2015 report in Skeptical Science, “water vapor feedback roughly doubles the amount of warming caused by CO2. So if there is a 1°C change caused by CO2, the water vapor will cause the temperature to go up another 1°C. When other feedback loops are included, the total warming from a potential 1°C change caused by CO2 is, in reality, as much as 3°C.”
40. Soil microbial communities release unexpectedly more carbon dioxide when temperatures rise (Nature, 4 September 2014). As a result, “substantial carbon stores in Arctic and boreal soils could be more vulnerable to climate warming than currently predicted.”
41. “During the last glacial termination, the upwelling strength of the southern polar limb of the Atlantic Meridional Overturning Circulation varied, changing the ventilation and stratification of the high-latitude Southern Ocean. During the same period, at least two phases of abrupt global sea-level rise—meltwater pulses—took place.” In other words, when the ocean around Antarctica became more stratified, or layered, warm water at depth melted the ice sheet faster than when the ocean was less stratified. (Nature Communications, 29 September 2014) Robert Scribbler refers to AMOC as “the heartbeat of the world ocean system.” As reported in the 23 March 2015 online issue of Climatic Change, the slowing of the AMOC is “exceptional” and is tied to melting ice in Greenland. This twentieth-century slowdown apparently is unique, at least within the last thousand years.
42. “Open oceans are much less efficient than sea ice when it comes to emitting in the far-infrared region of the spectrum. This means that the Arctic Ocean traps much of the energy in far-infrared radiation, a previously unknown phenomenon that is likely contributing to the warming of the polar climate.” (Proceedings of the National Academy of Sciences, November 2014)
43. Dark snow is no longer restricted to Greenland. Rather, it’s come to much of the northern hemisphere, as reported in the 25 November 2014 issue of the Journal of Geophysical Research. Eric Holthaus’s description of this phenomenon in the 13 January 2015 edition of Slate includes a quote from one of the scientists involved in the research project: “The climate models need to be adding in a process they don’t currently have, because that stuff in the atmosphere is having a big climate effect.” In other words, as with the other major self-reinforcing feedback loops, dark snow is not included in contemporary models.
44. The “representation of stratospheric ozone in climate models can have a first-order impact on estimates of effective climate sensitivity.” (Nature Climate Change, December 2014)
45. “While scientists believe that global warming will release methane from gas hydrates worldwide, most of the current focus has been on deposits in the Arctic. This paper estimates that from 1970 to 2013, some 4 million metric tons of methane has been released from hydrate decomposition off Washington [state]. That’s an amount each year equal to the methane from natural gas released in the 2010 Deepwater Horizon blowout off the coast of Louisiana, and 500 times the rate at which methane is naturally released from the seafloor.” (Geophysical Research Letters, online version 5 December 2014)
46. “An increase in human-made carbon dioxide in the atmosphere could initiate a chain reaction between plants and microorganisms that would unsettle one of the largest carbon reservoirs on the planet — soil” (Nature Climate Change, December 2014 )
47. Increased temperature of the ocean contributes to reduced storage of carbon dioxide. “Results suggest that predicted future increases in ocean temperature will result in reduced CO2 storage by the oceans” (Proceedings of the National Academy of Sciences, January 2015)
48. According to a paper in the 19 January 2015 issue of Nature Geoscience, melting glaciers contribute substantial carbon to the atmosphere, with “approximately 13% of the annual flux of glacier dissolved organic carbon is a result of glacier mass loss. These losses are expected to accelerate.”
49. According to a paper in the 20 April 2015 online issue of Nature Geoscience, ocean currents disturb methane-eating bacteria. “We were able to show that strength and variability of ocean currents control the prevalence of methanotrophic bacteria”, says Lea Steinle from University of Basel and the lead author of the study, “therefore, large bacteria populations cannot develop in a strong current, which consequently leads to less methane consumption.”
50. Arctic warming is amplified by phytoplankton under greenhouse warming (Proceedings of the National Academy of Sciences, 12 May 2015). Temperatures in the Arctic are warming considerably faster than the global average, largely because of diminishing sea ice. According to this research, the biogeophysical effect of future phytoplankton changes amplifies Arctic warming by 20%.
51. Cryptogamic covers, which comprise some of the oldest forms of terrestrial life, have recently been found to fix large amounts of nitrogen and carbon dioxide from the atmosphere. They are sources of greenhouse gases, notably including nitrous oxide and methane, with higher temperatures and enhanced nitrogen deposition contributing to amplification (Global Change Biology, 7 July 2015).
52. The impact of phytoplankton is not restricted to the Arctic, either. Rather, plankton in the Southern Ocean are responsible for creating nearly half of the water droplets in the clouds during the summer, thus serving as a cooling agent (Science Advances, 17 July 2015).
53. “Observations show that glaciers around the world are in retreat and losing mass” (Journal of Glaciology, July 2015). According to the final lines of the abstract: “Glaciological and geodetic observations (~5200 since 1850) show that the rates of early 21st-century mass loss are without precedent on a global scale, at least for the time period observed and probably also for recorded history, as indicated also in reconstructions from written and illustrated documents. This strong imbalance implies that glaciers in many regions will very likely suffer further ice loss, even if climate remains stable.”
54. From a paper in the 1 September 2015 issue of Nature Communications comes evidence that increased ocean acidification drives irreversible, large increases in nitrogen fixation and growth rates of a key group of ocean bacteria known as Trichodesmium. Trichodesmium is one of the few organisms in the ocean that can “fix” atmospheric nitrogen gas, making it available to other organisms. It is crucial because all life — from algae to whales — needs nitrogen to grow. Climate change could send Trichodesmium into overdrive, with no way to stop, thus reproducing faster and generating lots more nitrogen. Without the ability to slow down, however, the bacteria has the potential to gobble up all its available resources, which could trigger die-offs of the microorganism and the higher organisms that depend on it. The change is projected to be irreversible and large even after being moved back to lower carbon-dioxide levels for hundreds of generations. According to the abstract of the paper: “This represents an unprecedented microbial evolutionary response, as reproductive fitness increases acquired in the selection environment are maintained after returning to the ancestral environment.”
55. The extinction of megafauna both at land and at sea has led to a shortage of mega manure (Proceedings of the National Academy of Sciences, 26 October 2015). As a result, the planet’s composting and nutrient-recycling system is broken. Other factors have contributed to extinction of large animals, too, but the role of megafauna poop in ecosystem function has been little studied in the past.
56. A paper in the 26 November 2015 issue of Science reports the rapid increase in coccolithophores in response to increased carbon dioxide. These algae make it more difficult to remove carbon dioxide from the atmosphere in the short term.
57. The “apparent sensitivity of respiration to nighttime temperatures, which are projected to increase faster than global average temperatures, suggests that C stored in tropical forests may be vulnerable to future warming,” according to a paper published in the 7 December 2015 online issue of Proceedings of the National Academy of Sciences. The paper suggests that hotter nights may actually wield much greater influence over the planet’s atmosphere than hotter days — and could eventually lead to more carbon flooding the atmosphere.
58. According to a paper in the 18 December 2015 issue of Science Advances, “Many large tropical trees with sizeable contributions to carbon stock rely on large vertebrates for seed dispersal and regeneration, however many of these frugivores are threatened by hunting, illegal trade, and habitat loss. … we found that defaunation has the potential to significantly erode carbon storage even when only a small proportion of large-seeded trees are extirpated.” In other words, climate change that causes loss of habitat for animals reduces the ability of tropical forests to store carbon, thus creating a self-reinforcing feedback loop.
59. From the 22 December 2015 online issue of the Proceedings of the National Academy of Sciences comes a paper pointing out the link between Arctic sea ice and regional precipitation. The abstract of the paper includes the following lines: “Global climate is influenced by the Arctic hydrologic cycle, which is, in part, regulated by sea ice through its control on evaporation and precipitation. … We find that the independent, direct effect of sea ice on the increase of the percentage of Arctic sourced moisture … likely result in increases of precipitation and changes in energy balance, creating significant uncertainty for climate predictions.” In other words, to quote the lead author of the paper, “If you remove sea ice from an Arctic area, you open up the ocean to the atmosphere, and evaporate more water, which forms precipitation.”
60. The terrestrial biosphere is a net source of greenhouse gases to the atmosphere, according to a paper in the 10 March 2016 issue of Nature: “We find that the cumulative warming capacity of concurrent biogenic methane and nitrous oxide emissions is a factor of about two larger than the cooling effect resulting from the global land carbon dioxide uptake from 2001 to 2010. This results in a net positive cumulative impact of the three greenhouse gases on the planetary energy budget.”
Vladimir Romanovsky, a UAF geophysics professor who monitored ice wedge degradation for the study at a site in Canada, said the overall conclusions of the study were striking. In an interview coincident with publication of the paper, he said, “We were not expecting to see these dramatic changes. … Whatever is happening, it’s something new for at least the last 60 years in the Arctic.”
62. Increased atmospheric carbon dioxide makes rainwater more acidic. The result is a relatively weak form or carbonic acid. The rain falls on limestone and related carbonate rocks, thus releasing carbon dioxide from the rocks into the atmosphere. The stronger the carbonic acid, the more the limestone dissolves, hence releasing more carbon dioxide.
63. According to a paper published 22 June 2016 in Nature Communications, there’s a strawberry-colored algae blooming in the northern reaches of Earth. As more algae bloom, more snow thaws. And, nourished by the unfrozen water, even more of the microorganisms are able to grow. And so on. It’s a self-reinforcing feedback loop of the irreversible variety. I’ll quote from the abstract: “(R)ed snow, a common algal habitat blooming after the onset of melting, plays a crucial role in decreasing albedo. Our data reveal that red pigmented snow algae are cosmopolitan as well as independent of location-specific geochemical and mineralogical factors. The patterns for snow algal diversity, pigmentation and, consequently albedo, are ubiquitous across the Arctic and the reduction in albedo accelerates snow melt and increases the time and area of exposed bare ice. We estimated that the overall decrease in snow albedo by red pigmented snow algal blooms over the course of one melt season can be 13%. This will invariably result in higher melt rates.”
64 and 65. A study published in the 11 July 2016 online issue of Nature thoroughly documents one of the most profound planetary changes yet to be caused by a warming climate: The distribution of clouds all across Earth has shifted. Specifically, the shift has expanded subtropical dry zones, located between around 20 and 30 degrees latitude in both hemispheres, and also by raising cloud tops. Each of these changes worsens overall planetary warming. According to a story in the Washington Post accompanying the paper’s release, each of these two changes to clouds is a positive feedback to climate change.
66. A paper in the 25 July 2016 online issue of Nature Geoscience confirms and quantifies the long-held suspicion that the ability of land plants to store carbon declines as Earth warms. The reduced storage of carbon leads to higher atmospheric carbon dioxide, thus increasing Earth’s temperature and contributing to a self-reinforcing feedback loop.
67. Arctic drilling was fast-tracked by the Obama administration during the summer of 2012.
68. Supertankers are taking advantage of the slushy Arctic, demonstrating that every catastrophe represents a business opportunity, as pointed out by Professor of journalism Michael I. Niman and picked up by Truth-out (ArtVoice, September 2013)
69. As jet planes burn fuel and release carbon dioxide, the atmosphere warms and causes head winds to build up (Nature Climate Change, published online 13 July 2015).
As nearly as I can distinguish, only the latter three feedback processes are reversible at a temporal scale relevant to our species. Once you pull the tab on the can of beer, there’s no keeping the carbon dioxide from bubbling up and out. These feedbacks are not additive, they are multiplicative: They not only reinforce within a feedback, the feedbacks also reinforce among themselves (as realized even by Business Insider on 3 October 2013). Now that we’ve entered the era of expensive oil, I can’t imagine we’ll voluntarily terminate the process of drilling for oil and gas in the Arctic (or anywhere else). Nor will we willingly forgo a few dollars by failing to take advantage of the long-sought Northwest Passage or make any attempt to slow economic growth.
Robin Westenra provides an assessment of these positive feedbacks at Seemorerocks on 14 July 2013. It’s worth a look.