'Monster' El Nino could usher in decade of more and stronger events
Surfersvillage Global Surf News, 9 December, 2015 - Miami is experiencing the third-wettest December in local history while traditionally cold northern areas of the United States are exceptionally warm. What's going on with the weather?
The El Nino effects will leave the U.S. Northeast warmer than usual, the Midwest drier, and the West and the South wetter. And scientists have a message for everyone bracing for one of the strongest El Nino events on record: get used to it.
While El Nino oscillates on a more or less yearly cycle, another dynamic in Pacific Ocean water temperatures, known as the Pacific Decadal Oscillation (PDO), has the potential to accelerate global warming and increase the severity of El Nino episodes, scientists said. The last time the PDO was, as it may be now, in a prolonged positive, or "warm" phase, it corresponded with two of the strongest El Ninos on record.
"When you really have a monster El Nino, it could be enough to flip the PDO into a new phase for a decade or so," said William Patzert, a climatologist at NASA's Jet Propulsion Laboratory in California. "Keep your eyeballs peeled because maybe we're in for a decadal shift."
Previous warm phases have also coincided with increased precipitation on the U.S. West Coast, signaling potential relief for California from a severe drought.
Before January of 2014, the world experienced a 15-year period of mostly negative values for the Pacific oscillation, according to data maintained by Nathan Mantua, an atmospheric scientist at the National Oceanic and Atmospheric Administration's (NOAA) Joint Institute for the Study of the Atmosphere and Oceans.
That period saw only weak or moderate El Nino events. During the 21 years before that, the Pacific oscillation values trended mostly positive, a period that coincided with the 1982-83 and 1997-98 El Nino events, two of the strongest on record.
Now, scientists are beginning to wonder if the 15-year period of relative El Nino calm is coming to a close, marking the start of a warmer, stormier era akin to the 1980s and 90s.