Could Frozen Methane Cause Another Mass Extinction?

[Marduk2012 Profile]

Could Frozen Methane Cause Another Mass Extinction?


Ice and methane bubbles dance across the surface of the East Siberian Sea.

An invisible threat lies dormant at the bottom of our sea, a frightening gas that causes death and destruction whenever it escapes the ocean floor; it is methane. Methane is an incredibly powerful fuel which could devastate our planet by setting the atmosphere literally on fire with a single spark, like that from a bolt of lightning. A methane explosion would change the world into a fiery ball of death, a literal hell on earth.

What is Methane?
Methane is a fuel created biologically by decaying biological material. It is found in the ocean on the seafloor in a frozen form intermingled with water. This is called methane hydrate, a dormant form of methane that is of a condensed volume. When the methane hydrate melts, it reacts with oxygen and increases its volume over 150 times in size, and the gas is more powerful than the fossil fuels we use today. But more than 350 miles under the sea, the methane hydrate is relatively harmless. The volume that can be found is the scary part, which is over eighty-thousand times natural gas reserves, at two-hundred-thousand-trillion cubic feet.


Arctic seabeds are belching massive quantities of methane, according to a new study that says ocean permafrost is a huge and largely overlooked source of the powerful greenhouse gas, which has been linked to global warming. Previous research had found methane bubbling out of melting permafrost frozen soil in Arctic wetlands and lakes:
http://news.nationalgeographic.com/news ... thane.html


But the permafrost lining the deep, cold seas was thought to be staying frozen solid, holding in untold amounts of trapped methane. “It’s not the case anymore,” said study leader Natalia Shakhova, a biogeochemist at the University of Fairbanks, Alaska. “The permafrost is actually failing in its ability to preserve this leakage.”
Related: http://news.nationalgeographic.com/news ... beria.html


In fact, Shakhova and colleagues estimate that roughly eight million tons of methane are leaking into the atmosphere each year from the East Siberia Sea, fueling concerns of accelerated global warming.
Related: http://news.nationalgeographic.com/news ... ost-oceans


… Current average methane concentrations in the Arctic average about 1.85 parts per million, the highest in 400,000 years, said Shakhova. Concentrations above the East Siberian Arctic Shelf are even higher, and scientists are concerned because the undersea permafrost “has been showing signs of destabilization already,” she added. “If it further destabilizes, the methane emissions… would be significantly larger.” Geological records indicate that atmospheric methane concentrations have varied between about .3 to .4 parts per million during cold periods to .6 to .7 parts per million during warm periods.
Related: http://www.commondreams.org/headline/2010/03/05-6


Extinction by methane may have happened before

What caused the worst mass extinction in Earth’s history 251 million years ago? An asteroid or comet colliding with Earth? A greenhouse effect? Volcanic eruptions in Siberia? Or an entirely different culprit? A Northwestern University chemical engineer believes the culprit may be an enormous explosion of methane (natural gas) erupting from the ocean depths.

In an article published in the September issue of Geology, Gregory Ryskin, associate professor of chemical engineering, suggests that huge combustible clouds produced by methane gas trapped in stagnant bodies of water and suddenly released could have killed off the majority of marine life and land animals and plants at the end of the Permian era — long before dinosaurs lived and died. The mechanism also might explain other extinctions and climate perturbations (ice ages) and even the Biblical flood, as well as be the cause of future catastrophes.


Ryskin calculated that some 10,000 gigatons of dissolved methane could have accumulated in water near the ocean floor under high pressure. If released quickly, perhaps triggered by an earthquake, the resulting cloud of methane would have an explosive force about 10,000 times greater than the world’s entire stockpile of nuclear weapons. The huge conflagrations plus flooding and overturned oceans would cause the extinctions. (Approximately 95 percent of marine species and 70 percent of land species were lost.)


According to a paleo-climate study performed by NASA, 55 million years ago, some of the methane trapped beneath the ocean floor was released, which increased the Earth’s temperature by thirteen degrees. Methane, more powerful than carbon dioxide, trapped heat in the atmosphere, and caused extinction and planetary disruption. The global warming that triggered this emission was called the Late Paleocene Thermal Maximum, which lasted 100,000 years, caused in part by a shift in the continental plates at the time, which altered the pressure in the sea floor.