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Scientist Rues Early ‘Wedge’ Statements on Solving Climate Change

Solving climate change will be more difficult than some make it seem.

To hear some politicians speak these days, you’d think climate change could be solved as a happy side effect to creating jobs and reducing oil imports. Of course, the problem is much bigger than that. Just ask Robert Socolow, a professor at Princeton University and creator of the oft-cited “wedge” approach to reducing greenhouse gas emissions.

In 2004, Socolow published an article in the journal Science that said greenhouse gases could be reduced substantially by combining several existing technologies with conservation measures, each technology or strategy forming a wedge. No single approach would be enough, but taken together, these wedges could make a big difference. The Science paper began with the provocative statement that “humanity already possesses the fundamental scientific, technical, and industrial know-how to solve the carbon and climate problem for the next half-century.” The profound optimism of that remark has been used far and wide by those arguing for action on climate change.

But now, according to a report in National Geographic, Socolow says people should have read his paper more carefully.

He originally wrote that a combination of seven wedges, including reducing automobile travel and installing huge numbers of wind turbines, would make it possible to stabilize carbon dioxide concentrations at 500 parts per million. But he notes than none of these wedges would be particularly easy. The fuel economy of vehicles would have to double, 2 million wind turbines would have to be installed, and the amount of energy supplied by solar power would have to increase 700 times. Even then, he says, all the wedges would have done is keep annual emissions at about what they are now, which would likely still allow the world to warm by 3 degrees—hardly eliminating climate change. In comparison, global climate talks have focused on trying to limit temperature increases to just 2 degrees.

Socolow also says climate activists took his theory and extrapolated from it, suggesting, for example, that adding more wedges would make it possible to to decrease emissions more than he predicted. As a result, climate change began to seem like an easy problem to solve, which he thinks contributed to the lack of action since 2004. From National Geographic:

“With some help from wedges, the world decided that dealing with global warming wasn’t impossible, so it must be easy,” Socolow says. “There was a whole lot of simplification, that this is no big deal.”

He said his theory was intended to show the progress that could be made if people took steps such as halving our automobile travel, burying carbon emissions, or installing a million windmills. But instead of providing motivation, the wedges theory let people relax in the face of enormous challenges, he now says.

“The job went from impossible to easy” in part because of the wedges theory. “I was part of that.”

And from there, he says, a disturbing portion of the population moved to doubt that the problem is even real.

“I know no one who predicted that the climate change message would be rejected on a scale that it is now,” Socolow said at a recent seminar at Harvard’s Kennedy School of Government. “Scientists and environmentalists interested in getting climate taken seriously have failed beyond their wildest imaginations.

“This is a time for self-assessment,” he said.

The article goes on to quote Henry Lee, who directs the environment program at the Harvard Kennedy School’s Belfer Center for Science and International Affairs.

“I think we were victimized more by the advocacy community than by science,” Lee said. Using Socolow’s wedges theory and similar arguments, advocates suggested “you could get all of this and pay nothing. I think people feel angry now, that it’s going to cost them.”

Here’s an alternative explanation. A concerted effort to dispute the reality of climate change paired with economic hardship made Americans care less about the issue. It seems unlikely that telling people that climate change is difficult to solve will make people more likely to support climate change policy.

On the other hand, if such a policy is ever to become law–and stay law for the decades it will take to address the problem–people will certainly need to be convinced that climate change is a problem worth doing something about, and they’ll need to have a realistic idea of what sacrifices will be necessary to solve the problem. Trying to convince them that forcing utilities to use more expensive sources of electricity will help the economy, as some politicians and policy experts are doing, doesn’t seem to be working.

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