The responses to the G8′s climate… what? pledges? agreements in principle? rumors of an agreement to pledge a principle? continue to roll in, with Fred Pearce having easily the most interesting one I’ve seen so far, on Short Sharp Science, which is NewScientist.com’s blog:
G8 emissions pledge is ‘scientifically illiterate’ [•] (emphasis added):
It sounds big, but it just isn’t enough. Leaders of the G8 industrial nations meeting in Italy this week are likely to agree that the world must cut greenhouse gas emissions by 50 per cent by 2050. That means cuts of 80 per cent among the rich nations.
They will say that this is essential to keep global warming below 2 °C – widely regarded as the tipping point beyond which scary global feedbacks could wreck the climate system that keeps us fed and watered.
Sorry, guys, but this is scientifically illiterate. We might be lucky: if the atmosphere is less sensitive to those gases than most scientists suppose, it could be enough to keep us below 2 degrees, for a while at least. But the best estimate is that the world needs at least 80 per cent cuts in global emissions, and probably more like 100 per cent, to stay below two degrees.
The smart talk back at the climate lab is about negative emissions. We may need to construct a planetary air-conditioning system to keep us cool by sucking carbon dioxide out of the air.
…
The trouble is the science has moved on even faster. The planet is not waiting for the diplomats. Climate chaos is coming down the tracks fast.
Even a decade ago, most scientists figured that we could probably cope with doubling the levels of carbon dioxide in the atmosphere from pre-industrial levels. That is, going from 275 parts per million to 550 ppm. Right now, we are at approaching 390 ppm and pushing up by around 2 ppm a year. So it seemed that we had a bit of time.
But five years ago, with growing concern about climate tipping points, scientists began to see 450 ppm as the threshold we should not exceed. That’s a lot closer. We will be there in 30 years.
And more recently the talk has been about 350 ppm. In other words, because of the timelags involved in the whole global warming process, we will need to lower concentrations of greenhouse gases to below where they are now.
Either that or we may face the rapid breakup of the Greenland ice sheet, runaway African droughts, drowned cities and oceans so acid they dissolve coral reefs. As the cover story of New Scientist magazine eloquently put it last week: “It’s worse than we thought”.
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The White House is listening to its chief scientist, Nobel prize-winning energy campaigner Steve Chu, who certainly gets it. He tells Americans they will have to abandon California to the desert if they don’t act fast. He and Obama believe there can be a worldwide revolution in how we generate energy: a low-carbon revolution within a generation.
I believe that too. There are tipping points in human society, as well as the climate system. But will we reach ours in time to prevent nature going over the edge? That I don’t know.
(Notice that Pearce explains the 50%/80% difference that I mentioned in another post earlier today. I suspect he has it right.)
I can’t remember the last time I read something about energy or the environment that so concisely and accurately summed up my own views on a very big, important topic.
As bad as much of the news has been on the environmental front for some time, and as much of a shift as we’ve seen in public stances on climate chaos (nowhere more so than in the US, I’m delighted to add, for once), I think it’s clearly premature to leap to any conclusions about the “will we or won’t we fix it” question.
It’s very appealing to be intellectually lazy and cling to whatever preconceived notions we have and say, “Of course we can’t fix this! Put government in charge of something this vast? It’ll never work, and corporations are too greedy and shortsighted to make the needed changes unless forced” or “Sure we’ll fix it. We always do. Nothing to worry about.” Like everyone reading this, I know quite a few people in both of those camps. Some of you might even be in one of those camps.
We live in a world of fuzzy logic, with “I don’t know” sandwiched firmly between “Yes” and “No” on almost any interesting question. When it comes to our response to peak oil or climate chaos, the bad news is that we’ve already squandered a lot of time, which will only make doing the right thing that much harder. The good news is that the “I don’t know–and neither does anyone else” zone is pretty big, so it’s still (probably) not too late. The fat lady may be warming up in the wings, her gigantic Viking helmet in place, but unless we’ve effectively triggered[1] the permafrost bomb and simply don’t know it, we shouldn’t cede the spotlight to her just yet.
[1] By “effectively triggered” I mean: The permafrost is already starting to melt quickly enough to create a runaway feedback condition, or we’ve put so much CO2 and methane into the atmosphere that even a nearly complete cessation of new emissions would still let the warming “in the pipeline” to push the permafrost over the edge.
