What's To Blame For Wild Weather? 'La Nada' - Science News - redOrbit

NASA climatologist Bill Patzert names a different suspect: "La Nada."

"La Niña was strong in December," he says. "But back in January it pulled a disappearing act and left us with nothing – La Nada – to constrain the jet stream. Like an unruly teenager, the jet stream took advantage of the newfound freedom--and the results were disastrous."
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"Global warming is certainly happening," asserts Patzert, "but we can't discount global warming or blame it for the 2011 tornado season. We just don't know ... Yet."