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Fire and Ice -- The Risk


Fire from ice. Intriguing. What do we know about this strange strange substance that goes by the name methane clathrate? Wikipedia tells us:

Methane clathrate, also called methane hydrate or methane ice, is a form of water ice that contains a large amount of methane within its crystal structure (a clathrate hydrate). Originally thought to occur only in the outer regions of the solar system where temperatures are low and water ice is common, extremely large deposits of methane clathrate have been found under sediments on the ocean floors of Earth.

"Extremely large deposits?" So is that, like, good news or bad? Not surprisingly, it can be either, depending on who you ask. Let's talk about the bad news first. As shown in the picture, this ice can catch fire and burn or, like regular ice, it can simply warm up and melt. When methane clathrate burns, it's the methane that 's burning. From an environmental standpoint, burning the stuff is not so bad. Burning methane does release some CO2 (a greenhouse gas) into the atmosphere, but quite a bit less than any other fossil fuel. On the other hand, if you melt methane clathrate rather than burning it, you release methane gas itself into the atmosphere. Methane is also a greenhouse gas, but it's about 20 times as efficient as CO2 at heating up the atmosphere.

In other words, if you want global warming, methane will get you there a lot faster than CO2 emissions. (Not to disparage CO2 in this regard; it can be highly effective.

So, what happens if these "extremely large deposits" of methane clathrate frozen on the ocean floor begin to melt? There are two possible answers:

  1. Nothing.

  2. Potentially cataclysmic change in climate

The first scenario represents the normal course of things. Methane clathrate melts all the time, usually in small quantities that bubble up towards the ocean's surface. Before the bubbles can reach the surface, the methane is re-dissolved into the ocean where it benignly floats around until (presumably) it freezes back into clathrate.

The second scenario is obviously more dramatic; indirect evidence potentially supporting such a scenario has only recently been confirmed to occur.

Remarkable and unexpected support for this idea occurred when divers and scientists from UC Santa Barbara observed and videotaped a massive blowout of methane from the ocean floor. It happened in an area of gas and oil seepage coming out of small volcanoes in the ocean floor of the Santa Barbara channel -- called Shane Seep -- near an area known as the Coal Oil Point seep field. The blowout sounded like a freight train, according to the divers.

Aside from underwater measurements, a nearby meteorological station measured the methane "cloud" that emerged as being approximately 5,000 cubic feet, or equal to the volume of the entire first floor of a two-bedroom house. The research team also had a small plane in place, flown by the California Department of Conservation, shooting video of the event from the air.

[Marine Science Institute researcher Ira] Leifer explained that when this type of blowout event occurs, virtually all the gas from the seeps escapes into the atmosphere, unlike the emission of small bubbles from the ocean floor, which partially, or mostly, dissolve in the ocean water.

Large quantities of methane suddenly released into the atmosphere could have quite an impact on global climate. Granted, we would need to be talking about a much larger quantity of the gas than was observed in this particular blow-out, but there could be bigger blowouts or more of them could occur, or the methane might come from sources other than volcanic, leading us back to our fire-ice:

Over geologic time scales, global climate has cycled between warmer, interglacial periods and cooler, glacial periods. Many aspects of the forces underlying these dramatic changes remain unknown. Looking at past changes is highly relevant to understanding future climate changes, particularly given the large increase in atmospheric greenhouse gas concentrations in the atmosphere due to historically recent human activities such as burning fossil fuels.

One hypothesis, called the "Clathrate Gun" hypothesis, developed by James Kennett, professor of geological sciences at UCSB, proposes that past shifts from glacial to interglacial periods were caused by a massive decomposition of the marine methane hydrate deposits.

So if our planet is currently warmer than normal either because of human acitivty or because of where we happen to be in the climate cycle or through some unholy combination of those two factors, this would seem to be a particularly bad time for any massive decomposition of methane clathrate to occur. Unfortunately, the warmer the planet gets, the greater the risk may become.

Sounds pretty scary, potentially. It would seem that we're sitting on a time bomb. Or maybe there's another way of looking at it...

Part 2, Fire and Ice -- The Promise


The past 500 million years have recorded a number of runaway global warming episodes: the end-Permian, the end-Triassic, the Paleocene-Eocene, and two in the Jurassic.

Humans are emitting CO2 up to a hundred times faster than the volcanic eruptions that likely triggered past runaway global warming episodes (and 30 times faster than the trigger for the end-Permian, which resulted in the death of most life because of oxygen deprived ocean depths).

• There is an estimated 400 billion tons of methane trapped in permafrost ice.

• An estimated 50% of surface permafrost will melt by 2050, and 90% by 2100.

• Methane is more than 20 times as strong a greenhouse gas as CO2-the sudden release of just 35 billion tons of methane would be like doubling the CO2 in the air.

• Ocean bottom ice will start to melt-releasing some of the estimated 10,000 billion tons of methane trapped in it.

• The only solution is biological sequestration-removing the CO2 from the air after it is emitted.

Brad, your opinion is interesting, but I'd like to see some facts associated with that. I notice that you've dumped the same factoids in numerous locations. I'd like to see the journal articles that actually support each claim. I don't really care where you do it, as long as it's much more complete than the shoddy job you do here. In particular, the first two paragraphs and the last paragraph need evidence.

Humans are emitting CO2 up to a hundred times faster than the volcanic eruptions that likely triggered past runaway global warming episodes (and 30 times faster than the trigger for the end-Permian, which resulted in the death of most life because of oxygen deprived ocean depths).

This ignores that these volcanoes emitted CO2 over far longer periods, that they emitted huge quantities of other gases like sulfur dioxide, hydrogen sulfide, nitrogen oxides, and volcanic ash. The last is particularly effective in changing the chemistry of oceans since it readily introduces most minerals needed to trigger algae blooms. And needless to say, it's mere opinion that the CO2 released by these volcanoes and any resulting greenhouse effects helped the resulting extinctions.

We also ignore that CO2 levels were substantially higher then than they are now. The circumstances (particularly solar output and the distribution of the various photosynthesis processes out there). But there seems to be some evidence supporting thriving ecosystems in CO2 levels a factor of ten or more higher than current levels.

The current rate of human CO2 emission is claimed here to be greater than that of the periods of volcanic activity in the past. But we assume here that volcanic activity resulted in constant CO2 production which would be unjustified. Also, we ignore that volcanic activity continued for long periods of time. It's not obvious to me that human CO2 emission can continue at the current rate for a comparable period of time. We're using up both cheap oil and economically viable ecosystems to deforest.

Finally, the claim that "only" biological sequestration can remove CO2 from the air is erroneous. There are other possibilities 1) CO2 emission reduction, 2) no effort needed (in the case that global warming is overstated as a problem), 3) solar influx reduction or increasing the reflectivity of Earth or its atmosphere, and 4) mechanical methods for sequestering CO2.

Well, I saw that Al Gore movie and I'm convinced! Why do you hate Polar Bears Karl? Everyone who writes against humans being the cause of global warming has a financial state in global catastrophe...

There's also been a whole really scary novel written about this called "Mother of Storms" by John Barnes. Think five permanant Jupiter Red Spots circling Earth for years at a time...

Well, I got scared by one at the zoo. So they have it coming. And I don't have a financial stake in global catastrophe (yet) since my nuclear extortion business is still in the planning stages.

But it's so hard to argue against Al Gore and scary books. I'll just have to be anti-global warming. At least till I become an independent nuclear power.

PS, I wonder if Brad above was running some sort of astroturf campaign. He dumped the above message in a bunch of places without any follow up. Seems a little rude to me even if it's all true.

Thank you for reading my material. Frankly, I don't see the disconnect: methane hydrate is a large unstable carbon reserve. I recommend reading "Global warming: Prehistory may soon repeat itself," "Permafrost and the Global Carbon Budget," and "The Heat Death of American Dreams." We know about how much methane hydrate is in permafrost and the oceans, we know that it has melted repeatedly before with catastrophic results, and we know it is starting to melt now. Perhaps you are from Missouri, the "Show Me State?" Here is my email address if you want to continue this conversation: dobermantmacleod@aol.com

The obvious question to ask here is why such an event wasn't triggered 15,000 years or so ago when the Earth's temperature last rose substantially? My impression is that the current tundra are less than 15k years old while the tundra of that time would have been several times older and have had plenty of time to saturate with methyl hydrate.

Also, we ignore that ocean level has risen considerably in that period. I imagine the increased pressure of more than 100 meters of sea level rise will counter some degree of warming. Given that most of this stuff forms apparently under between 300 and 2000 meters of water, it appears to me that globally we have increased pressure of up to a quarter on all ocean deposits.

Finally, note that atmospheric methane has gone up by around 2.6% since 1992 (measuring the 1992 to 2001 period) while atmospheric CO2 went up by 4.1%. We should be seeing a sharper increase in methane levels IMHO, if it is getting released from artic tundra at large rates.

Also, I appreciate your reply. I apologize for the insinuation above.

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