Is It Hot in Here? Must Be Global Warming. - NYTimes.com

Researchers at Columbia University found a high correlation between a participant’s stance on global warming and how he perceived the outdoor temperature on the day he was asked about it. Study subjects were also more likely to say they would donate to a global warming charity on days they perceived to be unusually warm.
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There is a not-insignificant caveat: Those pointing to hot weather as evidence of global warming are, in the broadest sense, more likely to be right. Scientists at the National Center for Atmospheric Research in Colorado demonstrated last year that record high temperatures have occurred twice as often as record lows over the last decade.
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In 1988, James Hansen, a NASA climate scientist, spoke at a Senate hearing and famously thrust the issue of global warming on the national stage.

But he apparently had some help in making his point.

We “went in the night before and opened all the windows, I will admit, right? So that the air-conditioning wasn’t working inside the room,” recalled Timothy Wirth, the former Democratic senator from Colorado, in an interview with “Frontline” in 2007.

Mr. Hansen was “wiping his brow at the witness table,” Mr. Wirth said, “and giving this remarkable testimony.”