Deep and nasty recessions are terrible for all sorts of obvious reasons. But when it comes to thinking about climate change and greenhouse-gas emissions, the current economic slump will likely do two things: First, it will reduce sharply emissions in the short term, as energy use plummets. Second, thanks to the decline of oil and gas prices, combined with the credit crunch, we'll see investments in alternative energy sources dry up. That's exactly what we're now seeing. But how will it all shake out? According to James Kanter, a French energy consultant has just released a new report predicting that the drop in clean-energy investment will have a far greater impact over the long haul, which means that global greenhouse-gas emissions will actually end up being higher than they otherwise would be if we hadn't had a recession. That's... not good news. Tacking on caveats, though, is Michael Liebrich, the head of New Energy Finance, who suggests that this doesn't have to be the case—provided the government steps in:

In particular, he warned against falling back on simplistic assumptions that "greenery" remained a luxury for good economic times and that countries would put climate change and energy security concerns on hold "while they throw the kitchen sink" at rising unemployment.

Those efforts actually could benefit clean energy. Mr. Liebreich expected to see some governments putting public money into improving grids and stimulating clean energy research and development. Tax measures also could stimulate private sector construction of renewable energy capacity although he is a skeptical about the value of creating “green jobs” simply for the sake of boosting employment.

“If you are going to increase public investment, then it makes sense to do it in an area where the resulting assets are actually needed,” he cautioned.

I made a somewhat longer version of this argument in the print magazine, and, at least judging by the headlines today, it seems like we're actually going to get plenty of public investment—$700 billion over two years is the figure the Post is kicking around. (The details, though, are still disturbingly hazy for spending of this magnitude.)

--Bradford Plumer