Haunting the Library has dug out a wonderful statement from NASA back in 1999:
Why are winters warming up so much faster over Northern Hemisphere continents than over the rest of the globe? A new study by NASA researchers in the June 3 issue of the journal Nature is the first to link the well-documented large degree of North America and Eurasia winter warming and the associated wind changes to rising greenhouse gas levels in the atmosphere.
Do read the whole thing. And when you are done, take a look at this rather wonderful article on the Fox News website, which revisits a number of alarmist claims from the past. I particularly liked this one:
By the year 2000 the United Kingdom will be simply a small group of impoverished islands, inhabited by some 70 million hungry people ... If I were a gambler, I would take even money that England will not exist in the year 2000."
Ehrlich, Speech at British Institute For Biology, September 1971.