Ag Weather Forum

California Drought Details

Bryce Anderson
By  Bryce Anderson , DTN Senior Ag Meteorologist
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The following article, by reporter Paul Rogers of the San Jose California Mercury-News, has a good summary of the effect felt in California from the current extreme drought. The article also has some discussion about a long-term temperature feature in the north Pacific--a negative trend in the Pacific Decadal Oscillation, which may be a major factor in the drought's intensity. I have noted the negative PDO in long-term weather discussions both here and in presentations during the past couple years.--Bryce

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In a new dose of bad news for a state growing increasingly concerned about lack of rain, California's historically dry weather is expected to last for at least another three months, federal scientists said Thursday.

The dire forecast for the rest of the state's winter rain season came as federal officials classified much of California as being in "extreme drought." And the Obama administration declared 27 California counties, including most of the Bay Area, as "natural disaster areas," eligible for emergency federal loans for farmers.

Computer models based on data from satellites, buoys in the Pacific Ocean and other sources favor below-normal levels of rainfall for California, much of Nevada, Arizona, New Mexico and West Texas until April, according to a new report from the National Weather Service's Climate Prediction Center.

"There will be a few precipitation events, but we're looking at drier-than-normal conditions in February, March and April," said Matthew Rosencrans, a meteorologist with the agency, which is based in College Park, Md. "Right now we are saying the odds do not indicate a Miracle March, which is not a good thing."

To be sure, long-range forecasts are not as accurate as short-term weather forecasts. The 90-day precipitation outlook for the West has turned out to be right about 60 percent of the time over the last 20 years.

Gov. Jerry Brown was expected Friday in San Francisco to declare a drought emergency, which would make it easier to transfer water between different regions of the state, and raise awareness for conservation.

Meanwhile, the U.S. Drought Monitor, a weekly update of drought conditions by federal agencies and researchers at the University of Nebraska, classified large sections of Northern California, including the Bay Area, as the fourth most severe of five drought categories: "extreme drought."

"It means that things are not getting better. They are getting drier," said David Simeral, a meteorologist with the Western Regional Climate Center in Reno, who is part of the Drought Monitor team.

"We're starting to see a lot more impacts showing up around the state," he said. "Groundwater issues, low snowpack, less forage available for cattle grazing, more fire risk."

Farmers in 27 California counties -- including Santa Clara, Alameda, Contra Costa, Monterey and San Benito -- declared "natural disaster areas" and in eight adjacent counties -- including San Mateo and Santa Cruz -- can now receive low-interest federal loans.

"Our hearts go out to those California farmers and ranchers affected," U.S. Agriculture Secretary Tom Vilsack said.

Last week, 27 percent of California's land area was listed as being in "extreme drought." This week it is it is 63 percent -- the most since the Drought Monitor began 14 years ago.

California is a historically arid place. Los Angeles and San Jose, for example, each get about 15 inches of rain in an average year. That's the same amount as Casablanca, Morocco. The state has periodic droughts but has not suffered a sustained one since 1987-92.

Increasingly, political leaders and scientists are concerned that California is entering another such period. Sierra Nevada snowpack on Thursday was 17 percent of normal. Last year, most cities in the state received the lowest amount of rain in any living person's lifetime -- with records going back to 1850.

Although smaller water agencies, such as in Willits, in Mendocino County, where there is just a 100-day supply of water left, are struggling, most large Bay Area water districts have not called for rationing and don't plan to make a decision until March or April. Years of rebates for conservation and increased storage -- both underground at places like the Santa Clara Valley Water District, and in reservoirs, like the recently expanded Los Vaqueros Reservoir in Contra Costa County -- have put them in better positions than during previous dry spells, they say.

"We are in fair shape and examining our options. But we've been planning for this for a generation," said Abby Figueroa, a spokeswoman for the East Bay Municipal Utility District.

For the past 13 months, a huge ridge of high-pressure in the atmosphere has sat off the West Coast, blocking storms that normally would bring rain during winter months.

Such high-pressure zones normally rise and break down as temperatures change and the jet stream shifts every winter, but this one has been different. Some scientists say it may be linked to climate change, which has melted polar ice and warmed the oceans. Others, including many who strongly support the broad scientific consensus that the Earth is warming due to human burning of fossil fuels, say it is too early to know. It may be related to other factors, such as naturally occurring temperature fluctuations in the Pacific Ocean, similar to El Niño and La Niña, or simply random bad luck.

Part of the National Weather Service's 90-day dry outlook, however, is based on the fact that there is a large section of the North Pacific Ocean where water temperatures now are 4-5 degrees Fahrenheit warmer than the historic average, Rosencrans said. And water along the California coast is about 1 degree cooler than average -- a condition known as a negative Pacific Decadal Oscillation, which historically has been linked to more high pressure, and drier weather in years past.

Full article with graphics is here:…



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2/7/2014 | 11:07 AM CST
Actually I'm for building the pipe Actually I'm for building the pipeline. Pipelines are the cheapest and safest way to move liquids. Right now they are moving it by rail, remember the derailment in Canada, These trains could be moving grain. Canada is going to sell their crude to somebody. It might as well be us. I'm all for sun and wind, but they need to be cheaper. It's cents per kilowatts. Wind is 12cents. solar is $ ? . Coal is .02cents. They both need fossil fuel backup when the wind isn't blowing or the sun isn't shining. Let's use our energy reserves wisely. Our economy thrives on low cost energy. .
Jay Mcginnis
2/7/2014 | 7:26 AM CST
Well Frank at least we both agree that the XL pipeline shouldn't be built as it is for exporting oil! As for expensive energy I don't know what is cheaper then sunlight or wind. Solar PV cost has come down under the magical $1/watt so is cheaper then building a coal plant. But I guess your hard line conservatism keeps you with the fossils?
2/5/2014 | 8:13 AM CST
You're right Jay, about the food supply controlling the pop. CO2 is to plants what O2 is to animals. Higher levels let plants grow better. We couldn't feed the world now, without modern tec. We can't go back without killing off some of the worlds pop. Who decides who? All fossil fuels at one time were growing plants or animals. We have plenty of fossil fuels yet, we have to use them wisely. Look out the window, our air is pretty clean. It doesn't make sense to make our energy more expensive and export our coal to other countries that don't use it as clean as we do.
Jay Mcginnis
1/30/2014 | 7:05 AM CST
Actually we need to see that like other species that overpopulate CO2 is a natural way of controlling us. Fossil fuels have given us a huge food supply and when they diminish and the exhaust from them make our habitat unlivable our population will fall back to a sustainable population which is calculated to be 1 billion without fossil fuels helping. You can see the "bell curve" style population rises and declines with other animal species from biology 101. In other words when a food supply becomes unlimited the population explodes until it is used up, then there is a die off. Its reality.
Gary Conrad
1/25/2014 | 5:58 AM CST
1. can we start or stop rain? 2. can we start or stop snow? 3. can we start or stop a tornado? 4. can we start or stop a hurricane? 5. can we start or stop wind? 6. there were at least 5 ice ages in the past where the glaciers at one time were into southern Iowa. 6a. there were NO humans, NO cars, NO factories, NO cows farting, NO bull crap. IF WE CANNOT START OR STOP WEATHER ON THE SMALL SCALE, CAN WE REALLY, REALLY DO IT ON THE LARGE SCALE? does anyone have a tail that wags its dog?? man made global warming is gov'ment control of us.
Bryce Anderson
1/23/2014 | 9:19 AM CST
From Wikipedia regarding scientific consensus: "The historian of science Naomi Oreskes published an article in Science reporting that a survey of the abstracts of 928 science articles published between 1993 and 2003 showed none which disagreed explicitly with the notion of anthropogenic global warming. In an editorial published in the Washington Post, Oreskes stated that those who opposed these scientific findings are amplifying the normal range of scientific uncertainty about any facts into an appearance that there is a great scientific disagreement, or a lack of scientific consensus. Oreskes's findings were replicated by other methods that require no interpretation." A complete Wikipedia entry on the term "Scientific Consensus" is at this link:
Michael Jones
1/22/2014 | 6:35 AM CST
Bryce, in this story, broad scientific consensus on Earth warming due to Human burning of Fossil Fuels is listed as a possible cause. I am curious to know what is that Scientific consensus evidence?
Bryce Anderson
1/21/2014 | 10:32 AM CST
There is some, yes. Particularly with the drier trend going on in the southwestern Plains.
1/21/2014 | 10:04 AM CST
Bryce, Is there any concern with the high pressure in the western U.S. moving east to say the corn belt later this year?