Methane Belch May Pose Extinction Threat
PHOTO: Methane Hydrate or so-called flammable ice, which exists under intense pressure in seabeds.
The timing of the moronic "Carbon Belch Day" and Newt Gingrich’s "Drill Here, Drill Now" campaign couldn’t be more ironic. A spate of articles and studies have been released recently showing how carbon induced warming may trigger a cycle of positive feedback leading to abrupt methane releases from permafrost, tundra and seabeds. The effects of atmospheric methane are 20 to 60 times as potent as CO2. It was methane release 635 million years ago that transformed the earth from a snowball (with ice at the equator) into roughly the climate we have today.
Over at The Cost of Energy, Lou Grinzo summarized and provided excellent commentary on 4 of these articles. It’s definitely worth a read.
Probably the biggest, nastiest monster under my bed for some time has been the possibility of a massive methane release from the Arctic region kicking global warming into warp speed. To people who don’t follow this stuff as obsessively as I do, this probably sounds like I’ve suddenly enlisted in the tinfoil hat brigade. Let me explain, as it’s sadly nowhere near that nutty a concept.
First, consider that methane is a much more powerful greenhouse gas than CO2. It doesn’t hang around in the atmosphere nearly as long as does CO2, but the net effect, once you take that timing into account, is usually quoted as roughly 20 times more greenhouse forcing than an equivalent amount of CO2. That’s a scary-big number. (To be more precise, the effect is estimated to be 62 times higher over the first 20 years, and “only” 21 times higher over a century.)
Second, there are two main stores of methane: Methane hydrates (a.k.a. methane ice or methane clathrates) in oceans and methane trapped in permafrost in places like Siberia.
Third, is there any real threat that this stuff will wind up in the atmosphere? Actually, there is, as relatively small amounts have been measured bubbling out of Siberia thaw lakes for at least a couple of years. That same article states that Siberian methane releases are about 3.8 Tg/year, compared to IPCC’s estimates of 600 Tg/year for all methane emissions, so from just the permafrost the current methane releases seem to be pretty small compared to other sources, such as the one US government reports delicately refer to as “enteric fermentation” in livestock, a.k.a. cow farts.
Finally, we have the issue of just how bad a big methane emission could be, in terms of global warming. As it turns out, we may have a truly hair-raising historical precedent:
All this means… what, exactly?
Let me be as clear as possible about this: I’m not saying that we’re definitely on track for a rendezvous with a methane burp (or clathrate gun, as some call it) scenario. As the last bit of text quoted above points out, we don’t know where the tipping point is, even if we assume that these latest findings hold up to scientific scrutiny. And to be completely objective, they might not, although that’s not how I would bet my Internet connection right now.
For me, there are two factors that elevate the methane apocalypse from “dumb thing I read on the Internet and can now ignore” to “something I really hope we’re spending a lot of money researching, right now“. The first is the rate at which climate change is happening, not least of all in the Arctic ice situation, as shown on the home page of the NSIDC (National Snow and Ice Data Center). I’ve pointed out numerous times on this site that the worldwide climate is changing much quicker than we expected, which means that despite the best efforts of a lot of extremely smart and dedicated people we still don’t understand what’s going on as well as we’d prefer. Will the changes we’re seeing level off or even decline over the next few years? Or will feedback effects, from albedo flip (reflective ice being replaced by less reflective water or ground) to methane releases accelerate change, possibly to the point where no reduction in our CO2 emissions will save the day?
The other factor is the similarity of the scenario outlined in the last article I quoted from above to our current situation. The critical difference is that in 2008 we’re changing the CO2 level in the atmosphere at a lightning fast pace, by geologic standards, and with virtually no hope of reducing that buildup this century. We could very well be running, at full-speed and blindfolded, into the mother of all tipping points and triggering catastrophic effects in a few decades instead of hundreds or thousands of years.
Maybe the situation isn’t that dire. Maybe this is all a lot of worry over nothing, and there are negative feedbacks we either haven’t discovered or grossly underestimate that will buy us considerable time to reduce our CO2 emissions and then the level of CO2 in the atmosphere. But right now, it feels more like we’re playing Russian roulette with the biosphere instead of being prudent and applying the precautionary principle.
Everyone worries about natural disasters, and even meteor strikes. But how about a scenario where earth’s temperature rose 10-20 degrees over a couple of decades? Billions of deaths from mass-migration, hundred-foot sea-level rises, wars, lack of fresh water and starvation would inevitably ensue.
It seems like such sci-fi that nobody even wants to talk about it. But the fossil record shows that when the climate reaches a tipping point, such changes can happen with devastating speed. We could find out that the price of fossil energy could be the permanent demise of the very civilization it enabled. Oh, the irony.
Even if there were a 1% chance of this ocurring, aren’t the stakes high enough that we should at least have that conversation?
