Salinas Californian
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| Scott Borgioli, a meteorologist and owner of Visalia-based WeatherAg.com, was in Salinas Thursday using a weather station to determine how much water is necessary for crops with current weather conditions. Borgioli and his company have put out a report looking at whether a wet winter will come to drought-ridden California can be reliably predicted now. (Juan Villa, The Salinas Californian) |
After years of drought conditions that have developed into the worst California has seen since weather conditions were recorded here, people across the state have been anxious for some good news about the weather.
And in recent weeks they’ve gotten it, with reports about an unusually strong El Niño event — a warming of the waters in the equatorial Pacific Ocean that affects weather pattern — that’s raising the odds of a wet winter and spring in the state.
Some have gone as far to use “monster,” “Godzilla” and even “Bruce Lee” to describe this El Niño’s strength how much wet weather it might usher into the a state desperately in need of rain and snowpack.
In fact, the media has some people believing that this could be the winter that cancels the ill effects to California’s mega drought.
At least that’s what Scott Borgioli has been hearing among some of the farmers and ranchers who are his clients in the Central Valley, the Central Coast and other parts of the state.
“Almost every person I bump into is saying, hearing, ‘Record-breaking El Niño.’ That’s the correlation that people are assuming — that El Niño equals rain,” said Borgioli, a meteorologist and owner of WeatherAg, a Visalia-based forecasting service for the agricultural industry.
The problem, he said, is those expectations just aren’t realistic. At least not yet.
Borgioli said numerous computerized weather models show that the El Niño forming in the Pacific likely will be strong, maybe even very strong, which could affect weather here from about mid December through spring.
In fact, the National Oceanic and Atmospheric Administration’s Climate.gov blog puts the odds at 95 percent that the current El Niño will continue through this year’s rain season and describes it as “pretty strong,” while some experts put it on track to be stronger than the three strongest El Niño events recorded since the 1950s.
Prior to that, meteorologists didn’t have the equipment and ocean temperature data to track or even recognize the existence of El Niño.
While Borgioli agrees about the projected strength of the El Niño, he said, “For the purposes of simplicity, there is a misconception that a strong El Niño will 100 percent bring significant rainfall across California. The truth is a significant El Niño, in and of itself, will not cause strong rainfall across California.
“People may be missing that part of the story,” particularly since the media is focusing so hard on the strength of the El Niño and its potential effects, without focusing enough on the long-term drought situation and the fact that scientists have only a few decades of detailed information on El Niños.
And of the five known strong or very strong situations El Niño years recorded, heavy rains came only 75 percent of the time, Borgioli noted.
“Before we draw a conclusion of what we can expect this weather year — this rainy season — there is a lot of science that needs to come into play.”
So for about the past month and a half, Borgioli, an expert in extended weather patterns — or “osculations” — that include El Niño, has been studying the current one developing in the ocean between South America and the Indian Ocean and looking at the data from past events.
Earlier this week, he distributed a report of his findings and conclusions to news organizations, and he plans to distribute copies to his clients and post it online in order to give what he considers a more accurate appraisal of the weather and point out the limitations of making weather predictions so far ahead of winter.
“There’s so much misconception out there about El Niño that is obtained from various weather sources. I wanted to set the facts straight” as well as to explain the variables that could interfere with a wet winter. “Let’s put on the brakes. Let’s understand the components.”
And he’s not alone.
Bill Patzert, a climatologist and oceanographer for NASA’s Jet Propulsion Laboratory in Pasadena, hasn’t read WeatherAg’s report, but said, “I understand exactly what he’s saying.
“It’s similar to what I have said. There is no guaranteeing double the snowpack and the rainfall in California [this winter].”
Certainly, this current El Niño started out strong in January, and it’s just as strong now, and there is the possibility that it could be the the strongest of the three strongest El Niños ever recorded — in the 1972-73, 1982-83 and 1997-98 rain seasons — all of which ushered in heavy precipitation, Patzert said.
Why we’re in a drought
Part of WeatherAg’s analysis involves explaining in the 15-page report why California is in its fourth year of severe drought.
A big part of the reason for the drought is persistent high pressure that has “hugged” the eastern Pacific Ocean, off the California Coast in recent years that deflected storm systems north, away from California and some other western states.
“As long as I’ve seen, I’ve never seen a pattern like this. This current pattern has lasted a little more than 2 years,” said Borgioli.
This persistent pressure system stems form the Pacific Decadal Oscillation — or “PCO” — a phenomenon similar to El Niño in which ocean temperatures change every 10 to 30 years along a “horseshoe” pattern in the Pacific from off California’s coast to Canada’s Coast
“If it continues into this rainfall year, we will see a continuation of the storm tracks not making their way into California as often as we would expect with a strong El Niño.”
On top of that, other weather events likely would have to take place, along with a strong or very strong El Niño, to allow heavy storm activity in the state this winter and spring.
They include:
•A Madden-Julian oscillation, which essentially is an low-pressure system over the area where the western Pacific intersects with the Indian Ocean. This could “spin” additional moisture over the western Pacific and feed West Coast-bound storms, Borgioli said..
•Above-average barometric pressure over western North America and its coast, which could break down the pressure system that has been deflecting storms away western states, and “open the storm door” for California,” he explained.
•The PCO would have to remain in a warm phase, and it currently is doing so, Borgioli added.
And Patzert said, “El Niño is a marathon. It stared in January extremely strong, and it is exceptionally strong for September,” but it could still defy some predictions and weaken in the coming months.
But Warren Blier, a National Weather Service science officers at the San Francisco/Monterey Bay Area Weather Forecast Office, said he puts stock in the “vast majority” or forecasting models showing El Niño will continue to be strong, at least into the beginning of winter.
“I would say it’s likely we are going to have a wetter than normal winter, but it’s not definite. I wouldn’t go so far as saying extremely likely, but I would say likely.”
NOAA also puts the chances for a wet winter as stronger for Southern California than for the central and northern parts of the state. The agency puts the odds for rainier-than-average conditions across much of the central region at above 30 percent.
For his part, Patzert said that despite the Weather Service’s assertions, “I don’t say things we don’t’ know.”
As for Bogioli, he said it likely will not be until October or November before any reliable forecasts could be made for the coming winter, and the anomalous high pressure continues to sit off the coast, “and high pressure is very hard to break down.”
Still, he said, the data available about the current El Niño is reason to be optimistic about the possibility of a wet winter here, “but don’t bet the farm on it.”
And if all the events line up to bring a very wet winter to California, chances are the effects of the droughts could remain for years, Borgioili said.
For thing, current forecasts call for the storms that could approach California being fed by warmer, “tropical” air that would result in warmer storms that drop less snow in California’s mountain, which serves as a natural storage space for much of the state’s water, he said.
So capturing rain in dams, waterways and recharge basins for groundwater will be particularly crucial this winter and spring, Borgioli said.
And after experiencing the driest four successive winters since 1895, one wet winter — even a very wet on — will not be enough offset the water losses and recharge aquifers from the drought, he noted.
“We need three to four years of above-average precipitation to really bail California out of the drought. And I’m talking really above average,” about 140 to 150 percent above normal in the Central Valley alone, Borgioli said.
And even then, a lot of the natural, underground storage capacity for water has been lost, as areas of the state have sunk down because so much water has been pumped out from under them, he said.
“The ground really doesn’t just pop up” when water returns to the aquifers.
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