The BBC recently published an article that goes together well with two of my earlier posts. Like my post on how many greenhouse gasses humanity can safely emit and my post on the (absent) long-term future of the fossil fuel industry, it highlights how preventing catastrophic climate change obliges humanity to keep a significant proportion of all available fossil fuels in the ground. The BBC piece cites an article in Nature which argues that we must leave 75% of the remaining fossil fuels untouched, if we are to avoid dangerous climate change.
What this highlights is how the world has two great stocks of carbon, between which humanity is generating an ever-increasing flow: (a) the stock of fossil fuels, containing carbon dioxide that hasn’t been in the atmosphere since the Eocene period 30 – 50 million years ago, and (b) the stock of carbon dioxide currently in the atmosphere, trapping ever-more energy from the sun. If we are to live in a world without massive disorder, displacement, and upheaval by the end of the century, we need to start closing the spigot from (a) to (b), even though it will mean leaving a lot of usable fuel underground.
That will take more restraint than humanity has been able to muster for any collective project so far.
The Nature website now has a special section: “The Road to Copenhagen.”
This refers to the United Nations Framework Convention on Climate Change (UNFCCC) meeting there in December, which will hopefully produce a successor to the Kyoto Protocol.
Must have PPT in disappointing issue of Nature devoted to “The Coming Climate Crunch”
Nature has devoted much of its April 30 issue to “The Coming Climate Crunch” (subs. req’d). Sadly, after sitting through pretty much the whole thing, I can’t actually recommend anybody else see buy it. Any regular reader of this blog will learn very little new from the dozen or so articles — and the issue fails utterly to provide its readers with the two must-haves in any comprehensive coverage of the issue:
1. A clear and specific understanding of the plausible worst-case scenario impacts facing the world post-2050 on our current emissions path.
2. A clear and specific understanding of the core climate solutions, policies for their rapid deployment, and an understanding of why the total cost of action is so darn low — one tenth of a penny on the dollar.
29 April 2009
Hit the brakes hard
There is a climate splash in Nature this week, including a cover showing a tera-tonne weight, presumably meant to be made of carbon (could it be graphite?), dangling by a thread over the planet, and containing two new articles (Allen et al and Meinshausen et al), a “News & Views” piece written by two of us, and a couple commentaries urging us to “prepare to adapt to at least 4° C” and to think about what the worst case scenario (at 1000 ppm CO2) might look like.
“For starters, any public dialogue that talks about “percentage reductions in emissions” by a certain date is misleading. Because of the long residence time of CO2 in the atmosphere, it makes far more sense to talk about the amount of CO2 remaining to be released before we hit a peak CO2 concentration. Let’s call this the “remaining cumulative carbon emissions” method. After those emissions, we essentially need to emit zero carbon. This way of looking at the climate was first popularized by Krause, Bach, & Koomey, in an excellent book called “Energy Policy in the Greenhouse” (1992). It was revisited as a tool of understanding the climate challenge in two great Nature magazine articles this year. (Nature magazine is probably the most prestigious, and rigorous, of all the academic journals.) In one of those, Meinshausen et al., used this method of analysis to look at how you would limit the planet to 2 degrees C of warming.”