As we witness Global Warming increasing exponentially Arctic Methane release (you likely have seen youtube videos of people lighting methane on fire released through the ice in Siberia, Canada or Alaska so flames often go up 3 to 5 feet or more into the air. There is a report of a Russian dying from walking over a vent he didn't know about with a lit cigarette in his mouth by the way.
Another thing I am observing is that most people say we are headed for ongoing global warming. However, there is a paradoxical element to all this most people aren't facing realistically. When you have a dynamic in place like we presently have of increased evaporation which brings increased clouds, water, floods, snow, rain, we also have in this dynamic the possibility from clouds and precipitation of an ice age as well. And I don't think enough thought is given to this.
On top of this Arctic Methane release only makes evaporation worse because of increased greenhouse effect in upper atmosphere of Arctic Methane and undersea methane release. So, the dynamic isn't just only hotter and hotter it also could cause an ice age just as easily because of weather ocillations the way this whole thing is beginning to look. So, for example, with increased evaporation over the years we have increased clouds, rain, and flooding. But remember, you only need 10 inches of rain which creates 10 feet of snow under the right conditions to create an ice age effect as well. I call this the refrigeration effect where enough snow on the ground only creates more and more snow on the ground year around. So, I could see that Global warming through increased evaporation also could produce an ice age because of too much cloud cover over time which cools the lands down to the point where only 10 inches of rain converted to 10 feet of snow could then help create an ice age under the right conditions where it kept snowing year around because of the cooling effect of that much snow sort of like a refrigerator effect.
So, it isn't just global warming that is a potential problem but also a potential ice age from weather oscillation because of the ongoing dynamics of multiple events ongoing stemming from increased evaporation over time and too much cloud cover too much of the time.
So, from my point of view this all could go either way (global warming or ice age) or both depending upon when we are talking about. And this is even more true because of the association of Geomagnetic Excursions (we are now either in a geomagnetic reversal or excursion right now), It just hasn't been publicly disclosed by scientists which yet, because they may not know until 2100 which it is or later.
- Contribution to climate change. The release of methane from the Arctic is in itself a major contributor to global warming as a result of polar amplification.
- The IPCC Fifth Assessment Report determined that methane in the Earth's atmosphere is an important greenhouse gas with a global warming ... Arctic methane release ...
- Arctic storms may be speeding up global warming due to a faster release of methane gas ... They found the sea storms made the methane gas release faster into the ...
Arctic methane release
From Wikipedia, the free encyclopedia
Arctic methane release is the release of methane from seas and soils in permafrost regions of the Arctic. While a long-term natural process, it may be exacerbated by global warming. This results in a positive feedback effect, as methane is itself a powerful greenhouse gas. The feedback of the undisturbed process is comparably weak, however, because the local release leads to a warming spread over the whole globe.Time series of atmospheric methane concentration (1984-2005)
The Arctic region is one of the many natural sources of the greenhouse gas methane.[1] Global warming accelerates its release, due to both release of methane from existing stores, and from methanogenesis in rotting biomass.[2] Large quantities of methane are stored in the Arctic in natural gas deposits, permafrost, and as submarine clathrates. Permafrost and clathrates degrade on warming, thus large releases of methane from these sources may arise as a result of global warming.[3][4] Other sources of methane include submarine taliks, river transport, ice complex retreat, submarine permafrost and decaying gas hydrate deposits.[5]
During interglacials, average atmospheric methane concentrations are nearly twice the lowest values in the depths of glacial. Concentrations in the Arctic atmosphere are higher by 8–10% than that in the Antarctic atmosphere. During cold glacier epochs, this gradient decreases to practically insignificant levels.[6] Land ecosystems are considered the main sources of this asymmetry, although it has been suggested that "the role of the Arctic Ocean is significantly underestimated."[7] Soil temperature and moisture levels have been found to be significant variables in soil methane fluxes in tundra environments.[8][9]
Contents
Contribution to climate change
The release of methane from the Arctic is in itself a major contributor to global warming as a result of polar amplification. Recent observations in the Siberian arctic show increased rates of methane release from the Arctic seabed.[4] Land-based permafrost, also in the Siberian arctic, was estimated in 2013 to release 17 million tonnes of methane per year - a significant increase on the 3.8 million tons estimated in 2006 and estimates before then of 0.5 million tonnes.[10][11][12] This compares to around 500 million tonnes released into the atmosphere annually from all sources.[10]
In the plot showing the global atmospheric methane concentration (the significant measure from the viewpoint of global warming and radiative forcing), however, the rate of the increase in atmospheric methane has been slowing until 2004, indicating that the contribution from Arctic release is currently not the dominant factor in the global picture.
Shakhova et al. (2008) estimate that not less than 1,400 Gt of Carbon is presently locked up as methane and methane hydrates under the Arctic submarine permafrost, and 5-10% of that area is subject to puncturing by open taliks. They conclude that "release of up to 50 Gt of predicted amount of hydrate storage [is] highly possible for abrupt release at any time". That would increase the methane content of the planet's atmosphere by a factor of twelve.[13]
In 2008 the United States Department of Energy National Laboratory system[14] identified potential clathrate destabilization in the Arctic as one of the most serious scenarios for abrupt climate change, which have been singled out for priority research. The U.S. Climate Change Science Program released a report in late December 2008 estimating the gravity of the risk of clathrate destabilization, alongside three other credible abrupt climate change scenarios.[15]
Loss of permafrost
Main article: PermafrostSea ice loss is correlated with warming of Northern latitudes. This has melting effects on permafrost, both in the sea,[16] and on land.[17] Lawrence et al. suggest that current rapid melting of the sea ice may induce a rapid melting of arctic permafrost.[17][18] This has consequential effects on methane release,[3] and wildlife.[17] Some studies imply a direct link, as they predict cold air passing over ice is replaced by warm air passing over the sea. This warm air carries heat to the permafrost around the Arctic, and melts it.[17] This permafrost then releases huge quantities of methane.[19] Methane release can be gaseous, but is also transported in solution by rivers.[5] NewScientist states that "Since existing models do not include feedback effects such as the heat generated by decomposition, the permafrost could melt far faster than generally thought."[20]
There is another possible mechanism for rapid methane release. As the Arctic ocean becomes more and more ice free, the ocean absorbs more of the incident energy from the sun. The Arctic ocean becomes warmer than the former ice cover and much more water vapour enters the air. At times when the adjacent land is colder than the sea, this causes rising air above the sea and an off-shore wind as air over the land comes in to replace the rising air over the sea. As the air rises, the dew point is reached and clouds form, releasing latent heat and further reinforcing the buoyancy of the air over the ocean. All this results in air being drawn from the south across the tundra rather than the present situation of cold air flowing toward the south from the cold sinking air over the Arctic ocean. The extra heat being drawn from the south further accelerates the warming of the permafrost and the Arctic ocean with increased release of methane.[citation needed]
Sinkholes discovered in the Yamal Peninsula in Siberia, Russia beginning in July 2014 are believed by Russian researchers to have been caused by methane released due to permafrost thawing. Near the bottom of the first sinkhole, air contained unusually high concentrations of methane, according to tests conducted by the researchers.[21] This hypothesis points to the destabilization of gas hydrates containing huge amounts of methane gas.[22]
According to researchers at Norway's Centre for Arctic Gas Hydrate (CAGE), through a process called geothermal heat flux, the Siberian permafrost which extends to the seabed of the Kara Sea, a section of the Arctic Ocean between the Yamal Peninsula and Novaya Zemlya, is thawing. According to a CAGE researcher, Aleksei Portnov,
"The thawing of permafrost on the ocean floor is an ongoing process, likely to be exaggerated by the global warming of the world´s oceans."
Methane hydrate is leaking in an area of at least 7500 m2. In some areas gas flares extend up to 25 m (82 ft). Prior to their research it was proposed that methane was tightly sealed into the permafrost by water depths up to 100 m (330 ft). Close to the shore however, where the permafrost seal tapers to as little as 20 m (66 ft), there are significant amounts of gas leakage.[22]
— CAGE 2014
Clathrate breakdown
Main article: Clathrate gun hypothesisSea ice, and the cold conditions it sustains, serves to stabilise methane deposits on and near the shoreline,[23] preventing the clathrate breaking down and outgassing methane into the atmosphere, causing further warming. Melting of this ice may release large quantities of methane, a powerful greenhouse gas into the atmosphere, causing further warming in a strong positive feedback cycle.[24]
The Permian–Triassic extinction event (the Great Dying) may have been caused by release of methane from clathrates. An estimated 52% of marine genus went extinct, representing 96% of all marine species.
Even with existing levels of warming and melting of the Arctic region, submarine methane releases linked to clathrate breakdown have been discovered,[25] and demonstrated to be leaking into the atmosphere.[5][26][27][28] A 2011 Russian survey off the East Siberian coast found plumes wider than one kilometer releasing methane directly into the atmosphere.[25]
According to monitoring carried out in 2003/2004 by Shakhova et al., the surface layer of shelf water in the East Siberian Sea and Laptev Sea was supersaturated up to 2500% relative to then present average atmospheric methane content of 1.85 ppm. Anomalously high concentrations (up to 154 nM or 4400% supersaturation) of dissolved methane in the bottom layer of shelf water suggest that the bottom layer is somehow affected by near-bottom sources. Considering the possible formation mechanisms of such plumes, their studies indicated thermoabrasion and the effects of shallow gas or gas hydrates release.[4]
Research in 2008 in the Siberian Arctic has shown clathrate-derived methane being released through perforations in the seabed permafrost.[29]
The climatic effects of a potential release of methane from global ocean clathrates may be significant on timescales of 1–100 thousand years, depending on the water temperature.[30]
See also
- Arctic dipole anomaly
- Atmospheric methane
- Clathrate gun hypothesis
- Clathrate hydrate
- Methane chimney
- Methane clathrate
- Long-term effects of global warming
- Permafrost Carbon Cycle
- Soil respiration
References
- Bloom, A. A.; Palmer, P. I.; Fraser, A.; Reay, D. S.; Frankenberg, C. (2010). "Large-Scale Controls of Methanogenesis Inferred from Methane and Gravity Spaceborne Data". Science 327 (5963): 322–325. Bibcode:2010Sci...327..322B. doi:10.1126/science.1175176. PMID 20075250.
- Archer, David; Buffett, Bruce (2005). "Time-dependent response of the global ocean clathrate reservoir to climatic and anthropogenic forcing" (PDF). Geochemistry, Geophysics, Geosystems – G3 6 (3): 1–13. Bibcode:2005GGG.....603002A. doi:10.1029/2004GC000854. Retrieved 2009-05-15.
External links
- Methane hydrates and global warming, RealClimate from December 12, 2005
- Arctic Methane Emergency Group UK Based 'Arctic Methane Emergency Group' calling for action on Arctic methane crisis
- Last Hours Film Short film about potential for massive release of arctic methane
- Methane Tracker Online tools to visualize atmospheric methane releases
- Film Arctic Methane: Why The Sea Ice Matters Featuring James Hansen, Peter Wadhams, and Natalia Shakhova
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