Your utility bill: possible evidence for global warming

So says a University of New Mexico climatologist.

David Gutzler, a University of New Mexico climatologist, has been tracking temperature increases over the past 50 years.
His work includes showing how much people use heaters in the winter and air conditioning in the summer. Since the 1960s, his charts show a 10 percent increase in air conditioner use in Albuquerque and a 10 percent decrease in heating use, he said.

Sounds pretty straightforward to me. The one concern I would have from the scientific side is that people are getting more “cushy” and hence using their AC more in summer without a strong correlation to rising temperatures. The heating reduction in winter, likewise, could be in part an artifact of people using more firewood. I assume he’s controlled for that in some way, but the story doesn’t make it clear.