RealClimate Is Alarmed by Arctic Methane, Should You Be?
RealClimate Commenter: Methane alarmism will not be dissuaded by any reasonable means. But nice try David. ;)Response [by geophysicist David Archer]: Well, to be honest, sometimes I do get spooked myself. There is a lot of carbon up there. David. PS: On further reflection, I don’t think I want to be fighting being alarmed about methane bubbles in the Arctic. I am alarmed too, but perhaps I’m alarmed for a longer time frame than some. David]
Whether or not you should be alarmed by Arctic methane depends on your definition of “alarmed.” And it depends on how much you follow the other areas of climate science, many of which are, for me, considerably more “alarming” (see “An Illustrated Guide to the Science of Global Warming Impacts: How We Know Inaction Is the Gravest Threat Humanity Faces“):
Something truly alarming (via M.I.T.): Inaction (our current “no policy” strategy) eliminates most of the uncertainty about whether or not future warming will be catastrophic. Aggressive emissions reductions — fatally rejected by deniers, the breakthrough bunch, and the ignorati — dramatically improves humanity’s chances.
But I’m getting ahead of myself. Concern about methane emissions has risen in recent years because methane levels have been risen in recent years after a decade of little growth and because there have been reports of massive methane plumes of the Arctic coast and because the carbon-rich permafrost is thawing.
Fortunately, the best NOAA analysis “suggests we have not yet activated strong climate feedbacks from permafrost and CH4 hydrates,” a finding Climate Progress first reported 3 years ago.
But much more rapid ice loss in the Arctic than expected, accompanied by rapid permafrost warming, has convinced leading experts now say that frozen carbon is likely to start being released at a large-scale in the next few decades – some of it in the form of methane, a far more potent greenhouse gas than CO2 — causing 2.5 times the warming of deforestation. That would complicate any efforts by humanity to reduce emissions and avert multiple, simultaneous catastrophes (see below). This largely unmodeled amplifying carbon-cycle feedback is, obviously, worrisome and even alarming.
As an aside, the word “alarm” literally meant “a call to arms” — as in, there is imminent danger folks, saddle up. So we have “alarm” defined as “a sudden fear caused by the realization of danger” or “a warning of existing or approaching danger.”
An another aside, the do-little crowd and their enablers/stenographers — you know who they are — have two big tricks to poo-pooh “alarmists.” First, they attack alarmists as predicting “certain doom,” pointing out that the models are filled with uncertainty and predict a large range of impacts. But they don’t tell you that their preferred course of action — doing very little — cuts out most of the uncertainty, sharply narrows the impact range, and thus dramatically increases the probability of the catastrophe (see MIT’s wheel of misfortune above).
Second, the snooze button pushers attack alarmists for supposedly saying we are experiencing a real-time catastrophe, but they are really hiding behind the lags in the energy and climate system. The climate realists are alarmed not because the doom hits in the next few years, but because if we don’t act aggressively in the next few years, the “doom” becomes exceedingly difficult to avoid.
In short, the do-little crowd and their enablers/stenographers have won the day politically, which means the alarmists have “won the day” scientifically. Put another way, anyone who isn’t alarmed right now, simply doesn’t know what they are talking about. As but one piece of proof: The historically staid and conservative International Energy Agency has joined the ranks of the “alarmists” — see IEA’s Bombshell Warning: We’re Headed Toward 11°F Global Warming and “Delaying Action Is a False Economy.”
The notion it’s alarmist to say that where we are headed is catastrophic is, well, just laughable … or cryable. As the chief economist for the IEA said in November about the fact that the world is on pace for 6°C (11 F) warming “Even School Children Know This Will Have Catastrophic Implications for All of Us.”
Darn you alarmist school children!
So we should retire the term “alarmist” and its variations. We are climate realists — or climate hawks, if you prefer. The snooze button pushers, well, they are still asleep at the wheel, which I wish were a mixed metaphor, but I guess those warning in the ads for Ambien are right — those pill-popping politicians and pundits driving the national and global SUV are sound asleep but don’t know it. And that’s not even counting the disinformers, who I guess in this extended metaphor are working desperately to unplug the alarm clock or encase it in tar sands. I digress.
Recently, geophysicist David Archer, an expert on the carbon cycle and methane hydrates, wrote three pieces on Arctic methane for the must-read website RealClimate. The first is titled, “Much ado about methane,” though it would have been better titled “Much ado about methane hydrates.” The second is “An Arctic methane worst-case scenario.” The third postdiscusses a model he created that you can play around with if you want an even worse case or a better one.
I am generally a fan of analyzing worst-case scenarios for two reasons. First, in real life, individuals base a considerable amount of their planning and spending on worst-case scenarios (fire burning down your house, catastrophic healthcare problem) and so do governments: Just think about how much money and material and manpower the U.S. has devoted since 1945 over the possibility of a Russian nuclear attack or tank invasion of West Europe or the need to fight two wars simultaneously, and so on. Second, many of those pesky worst-case scenarios somehow seem to keep happening where humans are involved — Fukushima being a classic example — which isn’t a big surprise given that ignoring warnings, which are sometimes called alarms, pretty much guarantees things are going to be worse than folks thought.
So here is what Archer finds in his worst-case scenario — if “the Arctic started to degas methane 100 times faster than it is today”:
… methane is a reactive gas and its presence leads to other greenhouse forcings, like the water vapor it decomposes into. Hansen estimates the “efficacy” of methane radiative forcing to be 1.4 (Hansen et al, 2005, Shindell et al, 2009), so that puts us to 4 or even 5 Watts/m2.This is about twice the radiative forcing today from all anthropogenic greenhouse gases today, or (again according to Modtran) it would translate to an equivalent CO2 at today’s methane concentration of about 750 ppm. That seems significant, for sure.Or, trying to “correct” for the different lifetimes of the gases using Global Warming Potentials, over a 100-year time horizon (which still way under-represents the lifetime of the CO2), you get that the methane would beequivalent to increasing CO2 to about 500 ppm, lower than 750 because the CO2forcing lasts longer than the methane, which the GWP calculation tries in its own myopic way to account for.But the methane worst case does not suddenly spell the extinction of human life on Earth. It does not lead to a runaway greenhouse. The worst-case methane scenario stands comparable to what CO2 can do. What CO2 will do, under business-as-usual, not in a wild blow-the-doors-off unpleasant surprise, but just in the absence of any pleasant surprises (like emission controls). At worst comparable to CO2 except that CO2 lasts essentially forever.
Fair enough. Archer says in the comments of the second post:
On further reflection, I don’t think I want to be fighting being alarmed about methane bubbles in the Arctic. I am alarmed too, but perhaps I’m alarmed for a longer time frame than some.
The thing is, we don’t need no stinking methane bubbles to be alarmed hawks. Business as usual is beyond catastrophic according to the recent scientific literature (see Our hellish future: Definitive NOAA-led report on U.S. climate impacts warns of scorching 9 to 11°F warming over most of inland U.S. by 2090 with Kansas above 90°F some 120 days a year — and that isn’t the worst case, it’s business as usual!)
I go through about 50 recent studies here. They make clear the key impacts we face in the coming decades if we stay anywhere near our current emissions path:
- Staggeringly high temperature rise, especially over land — some 10°F over much of the United States
- Permanent Dust Bowl conditions over the U.S. Southwest and many other heavily populated and arable regions around the globe
- Sea level rise of around 1 foot by 2050, then 4 to 6 feet (or more) by 2100, rising some 6 to 12 inches (or more) each decade thereafter
- Massive species loss on land and sea — perhaps 50% or more of all biodiversity
- Much more extreme weather
- Food insecurity — the increasingly difficulty task of feeding 7 billion, then 8 billion, and then 9 billion people in a world with an ever-worsening climate.
- Myriad direct health impacts
Remember, these will all be happening simultaneously and getting worse decade after decade. Equally tragic, a 2009 NOAA-led study found the worst impacts would be “largely irreversible for 1000 years.”
The single biggest failure of messaging by climate scientists (until very recently) has been the failure to explain to the public, opinion makers, and the media that business-as-usual warming results in simultaneous, ever-worsening impacts that, individually, are each beyond catastrophic, but combined are unimaginablly horrific.
By virtue of their success in promoting doubt and inaction, the snooze button pushers have, tragically and ironically, turned the worst-case scenario into business as usual.
If “the extinction of human life on Earth” or “a runaway greenhouse” are your criteria for being alarmed, then, you need methane hydrates.
If desperately trying to feed 9 billion people by mid-century in a world with a ruined, yet ever-worsening climate is your criterion — as I argued it should be in my recent Nature piece— then CO2 is more than sufficient to wake anyone up, sadly. Well, it’s sufficient to wake them up until they join the Obama administration — see Steven Chu on climate change (2/09): “Wake up,” America, “we’re looking at a scenario where there’s no more agriculture in California.”
Put another way, we’ve already got a 9-alarm fire we’re ignoring. One more alarm won’t wake up the Ambien crowd.
For the record, the worst-case scenario without methane hydrates is, well, pretty friggin’ bad:
- Royal Society Special Issue on Global Warming Details ‘Hellish Vision’ of 7°F (4°C) World — Which We May Face as early as the 2060s! “In such a 4°C world, the limits for human adaptation are likely to be exceeded in many parts of the world, while the limits for adaptation for natural systems would largely be exceeded throughout the world.”
Finally, I do think most of the people looking at the emissions from a defrosting tundra along with the potential for methane hydrate releases are probably not looking at the current business-as-usual warming cases, since those were the IPCC’s worst-case scenarios just a few years ago.
But it’s pretty clear that on business as usual, the Arctic is going to get very, very, very warm this decade (see “M.I.T. doubles its 2095 warming projection to 10°F — with 866 ppm and Arctic warming of 20°F“).
And that it will ultimately get even warmer than that:
- Science stunner — On our current emissions path, CO2 levels in 2100 will hit levels last seen when the Earth was 29°F (16°C) hotter: Paleoclimate data suggests CO2 “may have at least twice the effect on global temperatures than currently projected by computer models.”
But, of course, modern civilization as we know it today can’t survive anywhere near such warming. Surely humanity wouldn’t be so self-destructively unalarmed as to let this happen?
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