Reporting from Washington - As record snowfall buried the nation's capital this week, the quickest joke around town was, "So much for global warming." The quip was timely, given the recent controversies over Climategate -- the release of e-mails allegedly showing some leading climate scientists trying to suppress criticism -- and new questions about the integrity of the United Nations' Intergovernmental Panel on Climate Change. After 55-plus inches of snow fell in the Washington area, critics are delighting in the irony, and those who warn of climate change are taking pains to say the snow fits the pattern of a warming world. So who's right? If the earth is warming, why all the snow? Snow and global warming aren't mutually exclusive, climate scientists say. For starters, the amount of recorded warming over the last century, about 1 degree Fahrenheit above preindustrial levels, is nowhere near enough to eradicate winter in the mid-Atlantic. Also, weather is variable: The planet would have extreme highs and lows with or without an overall warming trend. And for all the recent snow in Washington, it hasn't been that cold -- mostly in the 20s or low 30s. The average temperature in Washington in January, according to the National Climatic Data Center, was about a degree warmer than the average for the last 40 years. But the reverse is also true: The fact that Vancouver, Canada, is experiencing record-high temperatures and importing snow for the Winter Olympics doesn't prove a warming trend