The 06-07 El Nino: A Wuss?

A couple of days ago, the National Weather Service’s Climate Prediction Center predicted a warmer-than-usual winter, with El Nino conditions bringing a likelihood of increased rainfall to California and the West Coast. But an excellent follow-up story from Rob Krier at the San-Diego Union-Tribune points out that November in San Diego for the last forty years has been completely dry, unlike previous decades, and he went on to raise questions about not just the predicted rainfall  this winter, but the El Nino itself.

Krier quotes two experts, Nathan Mantua, at the University of Washington Climate Impacts Group,
and my helpful climatological friend Bill Patzert, at JPL. Mantua said:

“The El Niño in the tropics is doing its thing, and the jet stream in the Northern Pacific is doing its thing. My suspicion is that sometime this winter, the El Niño pattern will develop. It might not happen until January, February and March.”

But Patzert was more skeptical, suspecting that the Sea Surface Temperatures in the tropics will decline, and doubting that this El Nino will lead to a wet winter at all:

“This is definitely not a clear-cut, unambiguous El Niño. It looks like it’s holding, but certainly not intensifying. In 1997-98 [the last major El Niño year], the SST anomalies were the most positive in November. Then they started to weaken and break up.  Whatever happens this year [to the SSTs] will not be enough to give us a wet January, February and March."

Hmmm. Here’s the latest set of SST anomalies from NOAA. It’s a bit difficult to read, but as you can see, some of the projections tail off sharply in the months to come.