How accurate are El Nino forecasts?
Tim Barnett, who died in 1998, was a marine geophysicist and oceanographer at Scripps Institution of Oceanography of the University of California San Diego. This was a quantum leap forward for the meteorology community, which is still 50% with 10-day predictions.
This was the only, and last time an El Nino stormy for California had been successfully forecast. Storms in that season caused damage of $850 million to the state, and precipitation was double its usual amount. This is according to Jan Null from Golden Gate Weather Services.
Null, retired chief forecaster of the National Weather Service San Francisco Bay Area, said that there have been 25 La Ninas and 26 El Ninos since 1950. The vast majority of El Ninos failed to behave like those in 1982-83 or 1997-1998.
Null said that Stephen Curry, the Golden State Warriors point guard was the superstar of the game. Null said that sometimes another person has a great night and is a greater influence.
He said that the wet La Nina of last winter “totally changed the script.”
What are the odds of a wet winter?
Anderson, state climatologist Anderson, stated that an equal number of El Ninos in this century has produced both dry and wet seasons. He said that “El Nino alone does not always translate to wet conditions.”
According to the Scripps Institution Center for Western Weather and Water Extremes, there is a 50-50 chance of California experiencing a wetter-than-normal Winter, but this prediction is based on historical data and not long-range predictions.
The NOAA long-range weather forecast map for October showed equal chances of above-average or below-average rain this winter along the southernmost California coast, but the odds “leaned” towards greater-than-normal rainfall for the rest Southern California. This also extended to the Bay Area.
Last month, the Department of Water Resources warned residents that “strong El Nino conditions could lead to another wet season.”
Shang-Ping Xie is a Scripps Institution climate scientist who puts the odds of a wet El Nino this winter in California at 2-to-1.
He said, “We had three years of La Nina.” “Two of them were dry, and one wet. “The odds are similar to typical results that say La Nina favors dry winters.”
In both of the classic El Nino winters that California experienced, the month of March was the one to suffer the most from rain, wind, and damage.
“March is when we believe that the tropical ocean has the greatest influence on North America,” Xie stated.
Do other factors affect the forecast?
El Nino can have unpredictable behavior, but identifying it is fairly simple. It relies on a large patch of water that covers the equatorial Pacific and, when consistently warmer than normal, triggers the declaration of the phenomenon.
El Nino can cause atmospheric circulation to change along the equator. may also nudge the jet stream, which normally heads for the Pacific Northwest, southward. This will make that area drier while the Southeast becomes wetter.
Yu, a researcher at UC Irvine, was prompted to investigate possible causes after El Nino failed to show up in 2015-16. He now believes that other weather phenomena and man-made phenomena may be affecting the phenomenon.
He believes that global warming and possible deforestation of Southeast Asia has helped create a second patch of warm water adjacent to El Nino’s, which may be thwarting his old ways.
Yu stated that El Ninos in this century “have shifted westward, to the central Pacific region and lasted for longer. They are now multi-year events.” “El Nino has changed.”
Xie from Scripps, who thinks the odds are in favor of a stormy El Nino believes that climate change has an influence on this phenomenon. He said that the ocean surrounding the surface warming of El Nino also warms on a longer-term basis.
What happens when this warmth becomes the baseline for a larger swath in ocean?
“If this pattern continues in the future, El Nino’s influence will increase,” Xie stated.
El Nino data, he believes, may not be up to date.
He said, “There are still a lot questions that we need to answer.”
Null said that all eyes will be on the academic community to determine what happens with El Nino. This is especially true for the most populous state in the country, which is normally in its path.
He said, “It is a game of constant learning.” “We’ve evolved in our understanding about El Nino, but it was complicated by the warming of the oceans and atmosphere.”
Are we keeping up? He asked. “I don’t know.”