Excerpted from a thought-provoking piece by David Owen in The New Yorker (it’s short; I recommend reading the whole thing):

The world’s principal source of man-made greenhouse gases has always been prosperity. The recession makes that relationship easy to see: shuttered factories don’t spew carbon dioxide; the unemployed drive fewer miles and turn down their furnaces, air-conditioners, and swimming-pool heaters; struggling corporations and families cut back on air travel; even affluent people buy less throwaway junk. Gasoline consumption in the United States fell almost six per cent in 2008. That was the result not of a sudden greening of the American consciousness but of the rapid rise in the price of oil during the first half of the year, followed by the full efflorescence of the current economic mess. […]

The environmental benefits of economic decline, though real, are fragile, because they are vulnerable to intervention by governments, which, understandably, want to put people back to work and get them buying non-necessities again—through programs intended to revive ordinary consumer spending (which has a big carbon footprint), and through public-investment projects to build new roads and airports (ditto). Our best intentions regarding conservation and carbon reduction inevitably run up against the realities of foreclosure and bankruptcy and unemployment. How do we persuade people to drive less—an environmental necessity—while also encouraging them to revive our staggering economy by buying new cars?