A new poll shows a sharp decline over the last year in the percentage of Americans who see solid evidence that global temperatures are rising. According to the survey by the highly-reputable Pew Research Center, while 44% of respondents saw global warming as a very serious problem in April 2008, that's down to just 35% now. Of course, all things are relative. With the economy and unemployment such as it is, despite that miraculous stimulus bill, you can see how a problem that's not supposed to truly impact us for a while to come might slide down the pecking order. BUT, the survey also shows that now just 36% of Americans say global temperatures are rising as a result of human activity, down from 47% last year. That's a scientific belief, independent of the economy right? I'd argue otherwise. Wild speculation about man-made impact on the environment is a rich man's game. It's true that the warming we've seen until about a decade ago when it stopped - though exactly why and for how long is debated - either is or isn't partly man-made, regardless of the economy or regardless of what the public thinks. But when you don't feel so rich, somehow scientific evidence that seemed so compelling before simply isn't now.