TEOLAWKI, continued

TEOLAWKI - The End of Life as We Know It - continues to threaten.

First there was the supernova and galactic-attack scenarios.

Then the predicted return of the comet Genondahwayanung, which pretty much annihilated most life in North America when it came here the first time.

And then the massive gas cloud speeding toward a collision with the Milky Way!

And now, yet another insult: The earth's atmosphere may detonate.

It seems that about 55 million years ago, there was a massive warming of the earth (incredibly, before human beings existed!) that caused mass extinctions. Known as the Late Paleocene Thermal Maximum (LPTM), the warming period lasted about 100,000 years and ushered in the rise of mammals, leading eventually to the evolution of human beings.

Its cause? The release into the atmosphere of enormous amounts of methane.

A tremendous release of methane gas frozen beneath the sea floor heated the Earth by up to 13 degrees Fahrenheit (7 degrees Celsius) 55 million years ago, a new NASA study confirms. NASA scientists used data from a computer simulation of the paleo-climate to better understand the role of methane in climate change. While most greenhouse gas studies focus on carbon dioxide, methane is 20 times more potent as a heat-trapping gas in the atmosphere.

Methane is solvent in ocean waters, but below 500 meters in depth the cold and pressure forces the methane to become trapped within ice crystals. Generally, this ice (which can actually be set alight if brought to the surface) is embedded on or under the sea floor.

[H]owever, that might not always have been the case. A period of global warming, called the Late Paleocene Thermal Maximum (LPTM), occurred around 55 million years ago and lasted about 100,000 years. Current theory has linked this to a vast release of frozen methane from beneath the sea floor, which led to the earth warming as a result of increased greenhouse gases in the atmosphere.

The hypothetical cause of the release was the tectonic shifts of the continents, especially of the Indian subcontinent smashing (geologically speaking) into Asia breaking up the sea floor for thousands of miles and releasing trapped methane into the atmosphere.

But it gets worse! Some scientists say that with a properly large sea floor eruption, such as a massive earthquake, so much methane could be released into the air that the atmosphere itself could become literally a fuel-air explosive.

[T]here may be stagnant, oxygen-poor basins in the ocean where methane might accumulate. Even a small explosion could cause a catastrophe. Imagine what would happen if such an event occurred in the mid-Pacific. Tsunamis would be generated in continuous waves, striking Hawaii and the entire West Coast. Coastal areas would be flooded for miles inland. Methane/water clouds would auto-ignite and the massive fires could cause widespread destruction. Consequences could be global. Whatever humanity survives would be thrown into a Dark Age.

Now, there's some atmospheric warming for ya!