Posts
The following incorporates additional feedbacks identified from the literature since the original list was put together
(October, 2012)
Climate change –
8. Methane is being released from the Antarctic, too
Summer Ice Melt In Antarctica Is At The Highest Point In 1,000 Years, Researchers Say
20. Arctic
drilling was
fast-tracked by the Obama administration during the summer of 2012
The following are articles that illustrate the progression of warming and melting of the Arctic, not necessarily linked to positive feedbacks
(October, 2012)
Climate change –
positive
feedbacks
Seemorerocks
Guy
McPherson, in his summary
and update on climate change has
provided a list of exponential, non-linear positive feedbacks
Although some of these have had reasonable coverage in the media and the scientific press it is difficult to find confirming information. It seems to me that as things get worse the more of a media blackout there is - for instance on the scale of methane release in Siberia in 2012.
To help myself (and hopefully to assist readers to understand, I have had hunted out what I could on the growing list of feedbacks provided by Guy.
1. Methane hydrates are bubbling out the Arctic Ocean
Natalia
Shakhova, Igor
Semiletov at al
'Fountains'
of methane 1,000m across erupt from Arctic ice - a greenhouse gas 30
times more potent than carbon dioxide (Daily Mail, Dec 2011)
"The
Russian research vessel Academician Lavrentiev conducted a survey of
10,000 square miles of sea off the coast of eastern Siberia.
They
made a terrifying discovery - huge plumes of methane bubbles rising
to the surface from the seabed.
'We
found more than 100 fountains, some more than a kilometre across,'
said Dr Igor Semiletov, 'These are methane fields on a scale not seen
before. The emissions went directly into the atmosphere.'
Sea
of Okhotsk (June, 2013)
On
May 29 and June 2, 2013, sudden peak levels of methane in the
atmosphere were registered of respectively 2241 and 2238 ppb at an
altitude of 33,647.8 ft (10,255.8 mi). Such very high levels are
unusual, particularly at such a high altitude
(Nafeez
Ahmed, the Guardian, 24 July, 2013)
Disappearance
of Arctic sea ice could trigger devastating methane release costing
the world's entire GDP
(Nafeez
Ahmed, the Guardian, 5 August, 2013)
Dismissals
of catastrophic methane danger ignore robust science in favour of
outdated mythology of climate safety
"Since
the area of geological disjunctives (fault zones, tectonically and
seismically active areas) within the Siberian Arctic shelf composes
not less than 1-2% of the total area and area of open taliks (area of
melt through permafrost), acting as a pathway for methane escape
within the Siberian Arctic shelf reaches up to 5-10% of the total
area, we consider release
of up to 50 Gt of predicted amount of hydrate storage as highly
possible for abrupt release at any time".
Discusses
the methane emergency in relation to the IPCC report.
CARVE
Finds 150 Mile Wide Methane Plumes
Sea ice is very thin, as the Naval Research Laboratory animation below shows; large areas with a thickness of 1 meter to zero persist close to the North Pole, as discussed in an earlier post; the animation further shows the retreat of sea ice from the Kara Sea, north of Siberia, over the past 30 days (18 July)
Methane
hydrates can become destabilized due to changes in temperature or
pressure, as a result of earthquakes and shockwaves accompanying
them, severe storms, volcanic activity, coastal collapse and
landslides. Such events can be both primed and triggered by global
warming
2. Warm Atlantic water is defrosting the Arctic as it shoots through the Fram Strait
Warm Atlantic water is defrosting the Arctic as it shoots through the Fram Strait (Science, January 2011). This breakdown of the thermohaline conveyor belt is happening in the Antarctic as well.
The sudden cooling of Europe, triggered by collapse of the global thermohaline circulation in the north Atlantic and the slowing of the Gulf Stream has been popularized by the movies and the media. The southern half of the global thermohaline circulation is as important to global climate but has not been popularized. The global oceans' coldest water, Antarctic bottom water forms in several key spots around Antarctica. The water is so cold and dense that it spreads out along the bottom all of the major ocean basins except the north Atlantic and Arctic. Multiple recent reports provide strong evidence that the formation of Antarctic bottom water has slowed dramatically in response to massive subsurface melting of ice shelves and glaciers. The meltwater is freshening a layer of water found between depths of 50 and 150 meters. This lightened layer is impeding the formation of Antarctic bottom water, causing the Antarctic half of the global thermohaline circulation to falter
Warming North Atlantic water tied to heating Arctic, according to new study
"The temperatures of North Atlantic Ocean water flowing north into the Arctic Ocean adjacent to Greenland -- the warmest water in at least 2,000 years -- are likely related to the amplification of global warming in the Arctic, says a new international study involving the University of Colorado Boulder."
"Led by Robert Spielhagen of the Academy of Sciences, Humanities and Literature in Mainz, Germany, the study showed that water from the Fram Strait that runs between Greenland and Svalbard -- an archipelago constituting the northernmost part of Norway -- has warmed roughly 3.5 degrees Fahrenheit in the past century. The Fram Strait water temperatures today are about 2.5 degrees F warmer than during the Medieval Warm Period, which heated the North Atlantic from roughly 900 to 1300 and affected the climate in Northern Europe and northern North America."
3. Siberian methane vents have increased in size from less than a meter across in the summer of 2010 to about a kilometer across in 2011
It took quite a while to track down any reference to this; however, the independent published an important article where Dr. Igor Semiletov is quoted being impressed by the scale and density of the plumes compared with the year before (2010).
There are no reports for 2012 - it seems there might be a media blackout on this
Vast methane 'plumes' seen in Arctic ocean as sea ice retreats (the Independent, Dec 2011)
"Earlier
we found torch-like structures like this but they were only tens of
metres in diameter. This is the first time that we've found
continuous, powerful and impressive seeping structures more than
1,000 metres in diameter. It's amazing," Dr Semiletov said.
"I
was most impressed by the sheer scale and the high density of the
plumes. Over a relatively small area we found more than 100, but over
a wider area there should be thousands of them," he said.
4. Drought in the Amazon triggered the release of more
carbon than the United States in 2010
Special report: Catastrophic drought in the Amazon
Region set to outstrip US as CO2 emitter"A widespread drought in the Amazon rainforest last year caused the "lungs of the world" to produce more carbon dioxide than they absorbed, potentially leading to a dangerous acceleration of global warming. Scientists have calculated that the 2010 drought was more intense than the "one-in-100-year" drought of 2005.
"They are predicting it will result in some eight billion tonnes of carbon dioxide being expelled from the Amazon rainforest, which is more than the total annual carbon emissions of the United States. For the second time in less than a decade, the earth's greatest rainforest released more carbon dioxide than it absorbed because many of its trees dried out and died.
5. Peat in the world’s boreal forests is decomposing at an astonishing rate
15
July, 2013
In
late June and early July, Barrow Alaska showed two methane readings
in excess of 1975 parts per billion. Sadly, this most recent methane
spike is likely not to be an outlier....
....CARVE is finding its own
evidence of massive Arctic methane emissions. Charles Miller, NASA’s
principle investigator for the CARVE project, in a recent article,
noted that the mission had discovered numerous atmospheric methane
plumes in the Arctic. Some of these atmospheric plumes were of
immense and troubling size, stretching as wide as 150 miles across.
4. Drought in the Amazon triggered the release of more
carbon than the United States in 2010
Special report: Catastrophic drought in the Amazon
Region set to outstrip US as CO2 emitter"A widespread drought in the Amazon rainforest last year caused the "lungs of the world" to produce more carbon dioxide than they absorbed, potentially leading to a dangerous acceleration of global warming. Scientists have calculated that the 2010 drought was more intense than the "one-in-100-year" drought of 2005.
"They are predicting it will result in some eight billion tonnes of carbon dioxide being expelled from the Amazon rainforest, which is more than the total annual carbon emissions of the United States. For the second time in less than a decade, the earth's greatest rainforest released more carbon dioxide than it absorbed because many of its trees dried out and died.
5. Peat in the world’s boreal forests is decomposing at an astonishing rate
“For millennia, peatlands have served as an important sink for atmospheric CO2 and today represent a large soil carbon reservoir. While recent land use and wildfires have reduced carbon sequestration in tropical peatlands, the influence of disturbance on boreal peatlands is uncertain, yet it is important for predicting the fate of northern high-latitude carbon reserves. Here we quantify rates of organic matter storage and combustion losses in a boreal peatland subjected to long-term experimental drainage, a portion of which subsequently burned during a wildfire. We show that drainage doubled rates of organic matter accumulation in the soils of unburned plots. However, drainage also increased carbon losses during wildfire ninefold to 16.8±0.2 kg C m−2, equivalent to a loss of more than 450 years of peat accumulation. Interactions between peatland drainage and fire are likely to cause long-term carbon emissions to far exceed rates of carbon uptake, diminishing the northern peatland carbon sink”.
Wetlands: Drying Intensifying Wildfires, Carbon Release Ninefold, Study Finds
"Drying of northern wetlands has led to much more severe peatland wildfires and nine times as much carbon released into the atmosphere, according to new research led by a University of Guelph professor.
The study, published November 1 in Nature Communications, is the first to investigate the effect of drainage on carbon accumulation in northern peatlands and the vulnerability of that carbon to burning:.
6. Invasion of tall shrubs warms the soil, hence destabilizes the permafrost
"The
boreal trees and shrubs that are already invading the tundra regions
of the north are expected to expand their territory even further as
climate-change progresses. A study recently published in
Environmental
Research Letters
indicates that invading shrubs will increasingly warm the northern
high latitudes at a rate that depends on the height of the plants."
See also this: Is Global Warming breaking up the Integrity of the Permafrost?
7. Greenland ice is darkening
See also this: Is Global Warming breaking up the Integrity of the Permafrost?
7. Greenland ice is darkening
Greenland ice sheet albedo feedback: thermodynamics and atmospheric drivers
Why
Greenland's darkening ice has become a hot topic in climate science
Darkening
causes the snow to absorb more sunlight which in turn increases
meltingLast July, a record melting occurred on the Greenland ice
sheet. Even in some of the highest and coldest areas, field parties
observed rainfall with air temperatures several degrees above the
freezing point. A month before, it was as though Greenland expert
Jason Box had a crystal ball; he predicted this complete surface
melting in a scientific publication. Box's research then got broader
public visibility after climate activist and writer Bill McKibben
covered it in Rolling Stone magazThe basic premise of Box's study was
that observations reveal a progressive darkening of Greenland ice.
Darkening causes the white snow surface to absorb more sunlight which
in turn increases melting. Given that this process is likely to
continue, the impact on Greenland melt, and subsequent sea level
rise, will be profound.....
"The
Greenland ice sheet is losing mass (Barletta et al. 2012) and at
least half of this loss is caused by an increase in surface melt
(e.g. Tedesco et al. 2013). The other part is caused by increased
dynamic mass loss, as marine-terminating glaciers lose resistive
stresses (Nick et al. 2009) due to both retreat and meltwater
lubrication at the bed"
8. Methane is being released from the Antarctic, too
Potential methane reservoirs beneath Antarctica
LargeMethane Reservoirs Beneath Antarctic Ice Sheet, Study Suggests
"The Antarctic Ice Sheet could be an overlooked but important source of methane, a potent greenhouse gas, according to a report in the August 30 issue of Nature by an international team of scientists."
This report from the Arctic Methane Group provided the main confirmation of methane releases in the Antarctic
Methane
levels in the atmosphere above Antarctica peaked at 2249 parts per
billion on May 9, 2013
9. Russian
forest and bog fires are growing
Record Temperatures and Wildfires in Eastern Russia (June, 2012)
Forests and bog land in far eastern Russia have been burning since the beginning of June 2012. Contributing to the record fires have been the record temperatures of this past summer. This summer in Siberia has been one of hottest on record. The average temperature ranged around 93 degrees Fahrenheit and there doesn't seem to be any break in the weather coming anytime soon.
The fires in eastern Russia have affected the districts of Krasnoyarsk, Tuva, Irkutsk, Kurgan, and the Republic of Khakassia. Especially hard hit is the city of Tomsk. According to official figures, over 24,000 acres of land had been burnt in Tomsk by early August. The city has been covered by heavy smog for weeks and the airport has been out of operation since the beginning of July
Fires and Smoke in Russia
“Intense fires continued to rage in western Russia on August 4, 2010. Burning in dry peat bogs and forests, the fires produced a dense plume of smoke that reached across hundreds of kilometers. The Moderate Resolution Imaging Spectroradiometer (MODIS) captured this view of the fires and smoke in three consecutive overpasses on NASA’s Terra satellite. The smooth gray-brown smoke hangs over the Russian landscape, completely obscuring the ground in places. The top image provides a close view of the fires immediately southeast of Moscow, while the lower image shows the full extent of the smoke plume.”
10. Cracking of glaciers accelerates in the presence of increased carbon dioxide
Glaciers Cracking in the Presence of Carbon Dioxide
"The well-documented presence of excessive levels of carbon dioxide (CO2) in our atmosphere is causing global temperatures to rise and glaciers and ice caps to melt.
"New research, published October 11, in IOP Publishing's Journal of Physics D: Applied Physics, has shown that CO2 molecules may be having a more direct impact on the ice that covers our planet.
"Researchers from the Massachusetts Institute for Technology have shown that the material strength and fracture toughness of ice are decreased significantly under increasing concentrations of CO2 molecules, making ice caps and glaciers more vulnerable to cracking and splitting into pieces, as was seen recently when a huge crack in the Pine Island Glacier in Antarctica spawned a glacier the size of Berlin."
11. The Beaufort Gyre apparently has reversed course
"The
Arctic Ocean is largely surrounded by land, which limits the abilit
of sea ice to drift southward into warmer waters. Some ice
continually flows out of the Arctic through the Fram Strait east of
Greenland, but this ice loss has historically been offset by ice
growth in the Beaufort Gyre, where ice can last for years. But the
Beaufort Gyre has been a less effective nursery for thickening ice in
recent years; young ice is less likely to survive its trip through
the warm, southern part of the gyre"
12. Exposure to sunlight increases bacterial conversion of exposed soil carbon, thus accelerating thawing of the permafrost
"Ancient carbon trapped in Arctic permafrost is extremely sensitive to sunlight and, if exposed to the surface when long-frozen soils melt and collapse, can release climate-warming carbon dioxide gas into the atmosphere much faster than previously thought."University of Michigan ecologist and aquatic biogeochemist George Kling and his colleagues studied places in Arctic Alaska where permafrost is melting and is causing the overlying land surface to collapse, forming erosional holes and landslides and exposing long-buried soils to sunlight.
"They found that sunlight increases bacterial conversion of exposed soil carbon into carbon dioxide gas by at least 40 percent compared to carbon that remains in the dark. The team, led by Rose Cory of the University of North Carolina, reported its findings in an article to be published online Feb. 11 in the Proceedings of the National Academy of Sciences"
The Copenhagen Diagnosis notes that the global warming amplification (feedback) from carbon released as a result of permafrost melting has not been accounted for in any of the IPCC projections. A recent UN Environment Programme report warned that failing to account for this feedback will result in an underestimate of future warming
13. 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)
13. 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)
The
summer ice melt in parts of Antarctica is at its highest level in
1,000 years, Australian and British researchers reported on Monday,
adding new evidence of the impact of global warming on sensitive
Antarctic glaciers and ice shelves.
Researchers
from the Australian National University and the British Antarctic
Survey found data taken from an ice core also shows the summer ice
melt has been 10 times more intense over the past 50 years compared
with 600 years ago.
"It's
definitely evidence that the climate and the environment is changing
in this part of Antarctica," lead researcher Nerilie Abram said.
"A
new 1,000-year Antarctic Peninsula climate reconstruction shows that
summer ice melting has intensified almost ten-fold, and mostly since
the mid-20th century. Summer ice melt affects the stability of
Antarctic ice shelves and glaciers.
The
research, published this week in the journal Nature Geoscience, adds
new knowledge to the international effort that is required to
understand the causes of environmental change in Antarctica and to
make more accurate projections about the direct and indirect
contribution of Antarctica's ice shelves and glaciers to global sea
level rise."
Ice shelves lose more mass where the ice meets the sea than previously thought
14. 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
"A record flood that inundated large regions of Canada last week is now sending a large pulse of silty water out through the Mackenzie Delta and into the Beaufort Sea. The pulse of floodwater is so large and bears so much silt that it has painted a wide section of the Arctic Ocean near the Mackenzie Delta brown."
15. Slowing of the Jet stream causes weather blocs
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.
One result is the creation of weather blocks such as the recent very high temperatures in Alaska. As a result, boreal peat dries and catches fire like a coal seam.
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)
Unprecedented Jet Stream Wave Sparks 120+ Degree Temps in the US Southwest and Tundra Fires in Extreme Northern Canada.
New video couples interviews with two experts -- Rutgers' Jennifer Francis and Weather Underground's Jeff Masters -- to explore the 'Why?' of two years of mirror images of weather across North America
16. A Heinrich event - melt forces eventually reach a tipping point
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). 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".
17. Ocean acidification leads to release of less dimethyl sulphide (DMS) by plankton. DMS shields Earth from radiation
Climate change and decreasing seawater pH (ocean acidification)1 have widely been considered as uncoupled consequences of the anthropogenic CO2 perturbation2, 3. Recently, experiments in seawater enclosures (mesocosms) showed that concentrations of dimethylsulphide (DMS), a biogenic sulphur compound, were markedly lower in a low-pH environment4. Marine DMS emissions are the largest natural source of atmospheric sulphur5 and changes in their strength have the potential to alter the Earth’s radiation budget6. Here we establish observational-based relationships between pH changes and DMS concentrations to estimate changes in future DMS emissions with Earth system model7 climate simulations. Global DMS emissions decrease by about 18(±3)% in 2100 compared with pre-industrial times as a result of the combined effects of ocean acidification and climate change. The reduced DMS emissions induce a significant additional radiative forcing, of which 83% is attributed to the impact of ocean acidification, tantamount to an equilibrium temperature response between 0.23 and 0.48 K. Our results indicate that ocean acidification has the potential to exacerbate anthropogenic warming through a mechanism that is not considered at present in projections of future climate change.
18. Rising ocean temperatures will upset natural cycles of carbon dioxide, nitrogen and phosphorus, hence reducing plankton
New research from the University of East Anglia shows that rising ocean temperatures will upset natural cycles of carbon dioxide, nitrogen and phosphorus.
As
nearly as I can distinguish, only the latter feedback process is
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. 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).
---Guy
McPherson
21. Supertankers
are taking advantage of the slushy Arctic
Global
warming’s newest feedback loo
Scandinavian
shipowners say cargo routes through the Arctic, made possible by
warmer temperatures, would save money and emissions
UPDATES:
The second hottest June on record occurred during a period of the Pacific Oscillation that results in more upwelling of cooler waters from beneath the surface. This transfer of colder, deeper waters to the surface layer interacts with the atmosphere and tends to have a net cooling effect. The result, under normal conditions, is that Earth cools during these periods (18 July)
Since early June, a series of storms have consistently worn away at the central ice, resulting in thinning over an area that is usually very resilient to melt. This thinning has resulted in steep losses of sea ice concentration and thickness in a large swath near the North Pole and extending into the Laptev Sea. ((18 July)
Ice melting at the North Pole during the summer months isn't exactly a rare occurrence, but what's remarkable is the speed and extend of the recent loss, and what this could mean for the trend that scientists have been seeing in the past decade.
ENSO,
the global regulator for, generally, how much heat the world ocean
system dumps into the atmosphere, remained on the cool side of
neutral for much of August 2013. Ocean surface temperatures in the
Eastern Equatorial Pacific remained 1 to 2 degrees Celsius below the
1981-2010 average for most of the month. In a normal year, such
departures would tend to depress both global ocean and land surface
temperature averages. But, for the world’s global oceans and
related land atmospheric system, all was well outside the range of
normal
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