But is there really any evidence of an increased frequency of extreme weather events? A study from the Twentieth Century Reanalysis Project, has examined the evidence for such an increase, and found it lacking:
...the project's initial findings, published last month, show no evidence of an intensifying weather trend. "In the climate models, the extremes get more extreme as we move into a doubled CO2 world in 100 years," atmospheric scientist Gilbert Compo, one of the researchers on the project, tells me from his office at the University of Colorado, Boulder. "So we were surprised that none of the three major indices of climate variability that we used show a trend of increased circulation going back to 1871."So what accounts for our perspective that there are more extreme events? In my best guess, it's the ubiquity of news, and relentless scare mongering.
In other words, researchers have yet to find evidence of more-extreme weather patterns over the period, contrary to what the models predict. "There's no data-driven answer yet to the question of how human activity has affected extreme weather," adds Roger Pielke Jr., another University of Colorado climate researcher.