From a March 4 Washington Times editorial:
Driving snow froze the hopes of organizers of "the biggest global warming protest in history" Monday in Washington. With the government on a two-hour snow delay and the speaker of the House unable to attend because her flight was grounded by inclement weather, shivering protestors gathered on the west front of the Capitol, the latest victims of a climatological phenomenon known by the scientific community as the Gore Effect.
The Gore Effect was first noticed during a January 2004 global warming rally in New York City, held during one of the coldest days in the city's history. Since then, evidence has mounted of a correlation between global warming activism and severely cold weather.
A year ago a congressional media briefing on the Bingaman/Specter Climate Bill was cancelled due to a cold snap. In October 2008 London saw the first snow since 1922 while the House of Commons debated the Climate Change Bill. That same month Al Gore's appearance at Harvard University coincided with low temperatures that challenged 125-year records. Tellingly, the average global temperature for each of the 366 days in 2008 was below the average for Jan. 24, 2006, the date Gore's "An Inconvenient Truth" was released at the Sundance Film Festival.
Critics claim the Gore Effect is mere coincidence, though one could also argue that coincidence is also the basis for the anthropogenic theory of climate change. Alternative theories, e.g., citing the influence of sun spot activity, have gained increasing credence as scientists have noted global warming in recent years on other planets, which presumably have been human-free. Significant data issues have also arisen, such as the recent discovery of a chunk of Arctic sea ice the size of California that satellites had missed (but which in all probability had been known to polar bears).