On Wednesday morning, before a chaos of other obligations, I heard yet another panel on impending climate-change disasters, but this one left me strangely less despondent than some of the others. The speakers were Thomas Lovejoy, a long-time biodiversity expert, and David Hayes, who has recently become the #2 official in the Department of Interior.

Lovejoy's presentation began with a reminder of all the bad things that are happening to wildlife, to biodiversity, to life in the ocean, etc as CO2 levels in the atmosphere go up, taking temperatures with them. But then, in the pivot to the "you don't have to jump out the window just yet" part of the presentation, he emphasized how huge a role the Earth's own natural processes and vegetations -- its forests, grasslands, wetlands, even deserts -- can play in absorbing much larger quantities of carbon from the atmosphere than they do now and thereby reducing the greenhouse effect, if they are protected and managed in a different way. He called this process "Re-Greening the Emerald Planet," and he supplied several charts (which I don't have) to show how powerful the effect could be.

He tied this analysis to perhaps the most frequently-used chart in modern climate-change thinking -- one produced by McKinsey & Co and the McKinsey Global Institute comparing the relative costs of different measures to reduce greenhouse gas (GHG) levels in the atmosphere. (For more on the study, here. For discussion, here.) On the chart, the below-the-line items, on the left side, are GHG-reduction measures that save more money than they cost. Most of these are sheer efficiency measures (insulating buildings, switching to more efficient lights). The above-the-line escalating figures on the right are the rising costs of other abatement measures. The most expensive of them are high-tech "carbon capture and sequestrian" systems, plus protecting forests in heavily-populated Asian countries. (Click for larger.)



Lovejoy's point was that a lot of "re-greening" steps are near the middle of the chart, either actually saving money or costing very little compared with a variety of clean-energy technologies. For more on the latter, see Josh Green's new piece.

So far, so familiar for most people following the debate. But then Hayes stepped up with what was news to me. This was the announcement that the Department of Interior, which is by far the largest landowner in the United States, and which at various points in its history has been seen as a beacon of the "drill, baby, drill!" philosophy of land management (cf: James Watt, passim), was in fact now quite serious about applying a "Re-greening" approach to the 20 percent of the US landmass under its control.

Hayes gave more details than I will recount here. They boiled down to a sequence of: trying to measure and understand the carbon-absorption properties of the various lands under its control; seeing how they can be improved, including with market-based offsets; telling the story to the public of why protecting and expanding forests, grasslands, wetlands, etc has an important climate-change component; making forest-preservation an important part of international climate negotiations (rather than talking only about clean-energy sources); and a lot more. (Including changes in U.S. agriculture, which are of course outside Interior's direct control, so that instead of being, incredibly, a net emitter of greenhouse gases, it has a positive effect. This is related to the Food, Inc. discussion of industrial agriculture mentioned here.)

"If we can come up with some measures that are correct and that people can understand, and show instances where we can positively affect the carbon balance, that can be a huge sea change," Hayes said. "We can show people that there are affirmative things we can do to help our climate. I am very excited about it."

That doesn't solve all the problems, answer all the questions, etc. But it was surprising enough to hear from a senior DOI official and seemed politically and psychologically shrewd, in letting people think that there was some reaction to dire greenhouse gas projections other than holding their hands over their ears and wishing the whole problem would go away.

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