[Below is the original script. But a few changes may have been made during the recording of this audio podcast.]

When Barack Obama is sworn in as president on January 20, 2009, he’ll face many crises: the credit crunch, the war in Iraq and the defining environmental challenge of our time—climate change.

So what will Obama do about global warming? First and foremost, he has already recognized it as an “immediate threat” and warned of a “planet in peril.” So no more climate change denial or downplaying from the White House.

Further, Obama has pledged to reduce U.S. emissions to 1990 levels by 2020 and then a further 80 percent by 2050. To do that with the smallest economic impact, Obama favors a so-called cap-and-trade program.

Cap and trade is essentially a government-mandated pollution market. The feds set an overall limit for pollution, in this case greenhouse gases. Then they auctions permits to pollute. The permits can be bought by polluters, for example, owners of coal-fired power plants.

But let’s say a power company has started using wind farms.  It might then own the rights to pollute more than it actually does pollute. It could then sell its extra permits to other polluting companies struggling to meet their emissions quota. Over time, the feds lower the overall limits or caps. And the system reduces pollution cheaply.

Such cap-and-trade programs have already cut acid rain–causing sulfur dioxide pollution from power plants. And the same type of global warming pollution market just got started among the 10 states of the Northeast. Paired with a push for renewable energy, which President-elect Obama has called a “top priority,” cap and trade could be a real climate change on global warming.

—David Biello

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