Ppm, shmeepm: clearer language in global warming advocacy

During the August recess, the Center for Biological Diversity and Friends of the Earth organized a coalition of more than 300 groups that signed on to a letter to Sen. Barbara Boxer and the US Senate as a whole. The letter urges the Senate to pass global warming legislation stronger than the American Clean Energy and Security Act that passed out of the House this summer. The effort has garnered a respectable amount of press coverage, and fills a crucial vacuum. ACES was a terribly compromised bill that won’t reduce our greenhouse gas emissions by very much and is riddled with loopholes and corporate giveaways. A lot of the mainstream environmental groups either let the compromising happen without a peep or actively encouraged it. It’s nice to see some groups with a back bone!

I think what CBD and FOE are doing is excellent, from an organizing perspective. Their coalition is big, and it comprises more than just environmentally focused groups. Through their press attention, they are starting to create the notion that environmentalists are disappointed in the efforts of Congressional Democrats and to a lesser extent President Obama on global warming. We need to push back hard against moderate Dems who are in the pocket of the coal and oil industries! However, I think the vague manner in which they refer to climate science makes their efforts less effective than they could be, specifically in how they invoke the 350 ppm target of Dr. James Hansen.

The most important thing to improve in climate legislation is emissions targets, and the letter rightly starts there. It says, "The Senate bill must set an economy wide cap on greenhouse emissions that is consistent with the best available science." The problem is that the letter doesn’t define what that means except in terms of the level of carbon dioxide in our atmosphere globally. Instead of providing a specific minimum acceptable target for emissions reductions by 2020 or 2050, it launches into a discussion of whether we should aim for 350 ppm or 450 ppm (if you’re confused, don’t worry, your Senator probably is too). Although conceding that ACES won’t get us even to 450 ppm, it concludes that 350 ppm should be the goal without saying how we should get there. Not very clear, and thus probably not very effective.

Okay let’s take a step back for a moment. You may be asking, what the hell does 350 or 450 ppm mean? ppm means parts per million, the concentration of carbon dioxide in the atmosphere. Climate scientists have used models to find the level of carbon dioxide in the atmosphere past which the effects of global warming would be dangerous. Of course dangerous is a pretty subjective term. But still, the scientists of the Intergovernmental Panel on Climate Change agreed that anything more than a 2 degree C rise in average global temperature would be dangerous, and to prevent that from happening we would have to keep CO2 below 450 ppm in the atmosphere. We’re currently getting close to 390 ppm, after we started before the Industrial Revolution at 275 ppm, so we don’t have a lot of room to maneuver. (See this paper by Joe Romm of Climate Progress).

What’s the deal with 350? 350.org, as the name would suggest, has an excellent summary of why 350 is an important number. Dr. James Hansen of NASA, a climate hero who has been sounding the alarm since the 80’s, wrote a paper recently stating that we must reduce the level of CO2 below 350 ppm "if humanity wishes to preserve a planet similar to that on which civilization developed and to which life on Earth is adapted." Pretty scary stuff considering we’re well past 350. The paper found that the planet is warming faster than scientists previously believed and that the impacts will be worse, making the 450 ppm target too conservative.

So this coalition has told the Senate to shoot for 350 ppm. Clearly Congress can’t decree our way to 350 ppm, especially because we’re not the only polluter (though we are by far the biggest per capita). They would have to figure out how much we need to cut our pollution to do our part. Does the letter provide any specifics on that? No. For their call to have any concrete meaning, these groups need to provide a target for emissions cuts and they don’t.

To figure out how to push the envelope on global warming legislation, we need to keep in mind where things are now. ACES would cut our emissions 17% below 2005 levels by 2020. Where does that compare with what the IPCC said we need to do? The IPCC found that developed countries need to cut their emissions 25-40% below 1990 levels by 2020. Considering that as of 2007 our emissions were 16% higher than in 1990, ACES falls well short of what we need to do to get to 450 ppm. Furthermore, as Joe Romm notes in the paper cited above, the IPCC didn’t include carbon-cycle feedback in its predictions. These are effects of global warming that release more carbon and make warming worse, such as the methane and CO2 release from the melting of the Arctic permafrost. So even 25% below 1990 levels by 2020 might not hack it.

Unless the EU beefs up its efforts and China makes big changes in the next couple years, ACES won’t stop us from surpassing 450 ppm. If that’s the case, would clamoring for 350 ppm to be the target have much of an impact? I highly doubt it, especially considering that nobody has determined how much developed countries would have to cut their emissions to get to 350 ppm as far as I know (let me know if I’m wrong). It currently is not part of our discourse on climate policy so it can’t have a lot of relevance around legislation. It should be a part of that discourse, and these groups should push for that, but not in a letter to the Senate about the nitty gritty of climate legislation.

Instead they should demand that Congress hit a target for emissions reductions that is specific and practically meaningful. 25% below 1990 levels by 2020 is the minimum acceptable according to the IPCC for 450 ppm, and that would equate to a bit more than 35% below today’s levels. So if we doubled the emissions reductions in ACES we would get there. It’s very meaningful and easy to grasp that ACES fails in that it reduces our emissions only half as much as it should.

Now I doubt the Senate would get all the way to a 25% below 1990 levels by 2020 reduction, especially considering the filibuster and the disproportionate representation from coal states there. But a specific campaign to double the reductions of ACES might get them to make at least slightly deeper cuts. The recent science suggests that even if the developed world cut its emissions 25% below 1990 levels by 2020 we might not avoid disastrous impacts. But activists around the world need to work for as much cuts as we can within our various political systems to minimize the effects of global warming (that we’re already seeing now!), and we have to think pragmatically about how to do it. As such, bringing 350 ppm into the discussion around details of climate legislation doesn’t make a lot of sense.

So write your Senator. We must do better than the American Clean Energy and Security Act! Double those emissions reductions! (Tell them to get rid of the offsets too, but I don’t have time to write about that now). This would be a more effective approach to climate advocacy then talking about 350 ppm in a vague way.

PS That’s not to say 350.org, Bill McKibben, and Dr. Hansen should stop talking about 350. They’re doing a tremendous job of getting the word out about what dire straits we’re in and describing the huge gap between our miniscule efforts on global warming and the gravity of the problem. I just think bringing 350 into the discussion around the specifics of climate legislation isn’t very effective.