Causes of California drought linked to climate change

Causes of California drought linked to climate change
Scientists agree that the immediate cause of the California drought is a particularly stubborn "blocking ridge" over the northeastern Pacific -- popularly known as the Ridiculously Resilient Ridge, or "Triple R" -- that prevented winter storms from reaching California during the 2013 and 2014 rainy seasons. Credit: Daniel Swain, Stanford School of Earth Sciences

The atmospheric conditions associated with the unprecedented drought currently afflicting California are "very likely" linked to human-caused climate change, Stanford scientists say.

In a new study, a team led by Stanford scientist Noah Diffenbaugh used a novel combination of computer simulations and to show that a persistent region of high atmospheric pressure hovering over the Pacific Ocean that diverted storms away from California was much more likely to form in the presence of modern greenhouse gas concentrations.

The research, published on Sept. 29 as a supplement to this month's issue of the Bulletin of the American Meteorological Society, is one of the most comprehensive studies to investigate the link between climate change and California's ongoing drought.

"Our research finds that extreme atmospheric high pressure in this region—which is strongly linked to unusually low precipitation in California—is much more likely to occur today than prior to the human emission of that began during the Industrial Revolution in the 1800s," said Diffenbaugh, associate professor of Environmental Earth System Science at Stanford and a senior fellow at the Stanford Woods Institute for the Environment.

The exceptional drought currently crippling California is by some metrics the worst in state history. Combined with unusually warm temperatures and stagnant air conditions, the lack of precipitation has triggered a dangerous increase in wildfires and incidents of air pollution across the state. A recent report estimated that the water shortage would result in direct and indirect agricultural losses of at least $2.2 billion, and lead to the loss of more than 17,000 seasonal and part-time jobs in 2014 alone. Such impacts prompted California Governor Jerry Brown to declare a drought emergency, and the federal government to designate all 58 California counties as "natural disaster areas."

Stanford scientists explain the state of California's drought

Scientists agree that the immediate cause of the drought is a particularly stubborn "blocking ridge" over the northeastern Pacific –popularly known as the Ridiculously Resilient Ridge, or "Triple R"–that prevented winter storms from reaching California during the 2013 and 2014 rainy seasons.

Blocking ridges are regions of high atmospheric pressure that disrupt typical wind patterns in the atmosphere. "Winds respond to the spatial distribution of atmospheric pressure," said Daniel Swain, a graduate student in Diffenbaugh's lab and lead author of the study. "We have seen this amazingly persistent region of high pressure over the northeastern Pacific for many months now, which has substantially altered atmospheric flow and kept California largely dry."

Blocking ridges occur periodically at temperature latitudes, but the Triple R was exceptional for both its size and longevity. While it dissipated briefly during the summer months of 2013, it returned even stronger by fall 2013 and persisted through much of the winter, which is normally California's "wet season." "At its peak in January 2014, the Triple R extended from the subtropical Pacific between California and Hawaii to the coast of the Arctic Ocean north of Alaska," said Swain, who coined the term "ridiculously resilient ridge" last fall to highlight the unusually persistent nature of the offshore blocking ridge.

Cause of California drought linked to climate change
The drought crippling California is by some measures the worst in the state's history. Credit: NOAA

Like a large boulder that has tumbled into a narrow stream, the Triple R diverted the flow of high-speed air currents known as the jet stream far to the north, causing Pacific storms to bypass not only California, but also Oregon and Washington. As a result, rain and snow that would normally fall on the West Coast were instead re-routed to Alaska and as far north as the Arctic Circle.

An important question for scientists and decision-makers has been whether human-caused climate change has influenced the conditions responsible for California's drought. Given the important role of the Triple R, Diffenbaugh's team set out to measure the probability of such extreme ridging events. The team first assessed the rarity of the Triple R in the context of the 20th century historical record. They found that the combined persistence and intensity of the Triple R in 2013 was unrivaled by any event since 1948, which is when comprehensive information about the circulation of the atmosphere is first available.

To more directly address the question of whether climate change played a role in the probability of the 2013 event, the team collaborated with Bala Rajaratnam, assistant professor of Statistics and of Environmental Earth System Science, and an affiliated faculty of the Woods Institute for the Environment. Rajaratnam and his graduate students Michael Tsiang and Matz Haugen applied advanced statistical techniques to a large suite of . Using the Triple R as a benchmark, the group compared geopotential heights–an atmospheric property related to pressure– between two sets of climate model experiments. One set mirrored the present climate, in which the atmosphere is growing increasingly warm due to human emissions of carbon dioxide and other greenhouse gases. In the other set of experiments, greenhouse gases were kept at a level similar to those that existed just prior to the Industrial Revolution.

The interdisciplinary research team found that the extreme geopotential heights associated with the Triple R in 2013 were at least three times as likely to occur in the present climate as in the preindustrial climate. They also found that such extreme values are consistently tied to unusually low precipitation in California, and the formation of atmospheric ridges over the northeastern Pacific.

"We've demonstrated with high statistical confidence that the large-scale , similar to those associated with the Triple R, are far more likely to occur now than in the climate before we emitted large amounts of greenhouse gases," Rajaratnam said.

"In using these advanced statistical techniques to combine climate observations with model simulations, we've been able to better understand the ongoing drought in California," Diffenbaugh added. "This isn't a projection of 100 years in the future. This is an event that is more extreme than any in the observed record, and our research suggests that global warming is playing a role right now."


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Is climate change behind California's dry spell?

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Sep 29, 2014
Anytime a NOVEL combination of simulations is used, I'm suspect. Read, biased and skewed in the direction we want the results to be.

I have some novel explanations for your simulations.

Sep 29, 2014
The climate has been changing for 4.458 +-.030 billion years.

Go find something else to blather on about.

If you're seriously concerned about the environment and carbon emissions, you've got to support nuclear power. If you don't, you aren't serious about the environment, you're just lying to advance another agenda.

Sep 29, 2014
@Shootist,
Sure, but riddle me this, principal of action and reaction, LeChatelier's Principal. Change begets change.

I don't care what happened 4.45 Billion Years ago; but 100 years ago, 50 years ago, 10 years ago, now.

How about what's changing now that's changing climate?

Things usually take aeons, unless they are meteors or volcanoes. What could cause change over the last 100 years? 50? There has to be a change if only one could find it!

Sep 29, 2014
Oh, the desperation of the AGW Cult, they must travel far and wide to find the rare weather to fulfill their beliefs.

Sep 29, 2014
@Anti, unfortunately you're right, this article is somewhat lacking in causality. There is certainly an effect, but two tears does not a climate change make, though the causes may be interesting, and are certainly real.

Sep 29, 2014
The human cause is geoengineering, namely, Lockheed and Raytheon. http://www.geoeng...tch.org/

Sep 29, 2014
What's really new is paying people to hate on science.

Sep 29, 2014
California does puts tens of thousands of tons of CO2 in the atmosphere every year with uncontrolled forest fires. In fact, they put more CO2 in the atmosphere than all the power plants, coal and gas, in America combined. Some studies said 600% more. So if climate change is your goal, there is good place to start.

Sep 29, 2014
"The amount of CO2 emitted from fires in the U.S. is equivalent to 4-6% of anthorpogegentic emissions at the continental scale..."

http://www.cbmjou...t/2/1/10

Where are your links Porgie?

Sep 30, 2014
What's really new is paying people to hate on science.

What isn't new, are stupid people who are incapable of an independent thought and don't know what science is.

Sep 30, 2014
Yup, this California drought is caused by AGW, so say AGW scientists, who make money claiming the drought is caused by AGW, who then give money to Democrats who then say the science is settled, who then give more money to AGW scientist, who find more weather pattern....Democrats like this pattern as they get more money, get more power to regulated and destroy, AGW scientists like this as they get more money...

But wait, If you are a freethinker you start asking questions such as, has California ever had droughts before? If so, have they been worse? If so, was man to blame?

http://www.mercur...ted-more

Sep 30, 2014
What's really new is paying people to hate on science

What isn't new, are stupid people who are incapable of an independent thought and don't know what science is.
aaand that would be people who can't read and comprehend the mountains of data and the plethora of studies that support AGW and the global warming problem... like antiG...

@Ormond Otvos
Read this study: http://www.drexel...nge.ashx

You are CORRECT about people being paid to hate on science, and it is a PROVEN FACT that they are supported by big business, oil etc... because the business has a vested interest in keeping things as they are NOW to make billions more.

see also: http://phys.org/n...ate.html

that study I linked is linked in there as well.
You see the paid people above: freeT as well as antiG and waterboy

Sep 30, 2014
What's really new is paying people to hate on science.

What isn't new, are stupid people who are incapable of an independent thought and don't know what science is.


Yes. You have demonstrated that for us for years now, ad nauseum.

Are you going to continue ignoracle?

Sep 30, 2014
Yup, The DNC and Obama is using millions of dollars of government funds to WebMD to promote Obamacare. I wonder how much money WebMD gives back to the DNC?

I wonder how much money Physorg gets promoting Obamacare and AGW? How much of that then goes back to Obama and the DNC.

So how to tell if a poster is a Paid Progressive Government Troll, ask them which of Obama's or DNC policy they don't agree with. You ask them that question, a PPGT will not answer, because if they do they will lose a paycheck. They also fear they may then be audited by the IRS or investigated by the DOJ.

Independent thought, Corruption and fear knows no bounds with Progressives.

Sep 30, 2014
I wonder how much money Physorg gets promoting Obamacare and AGW?
@freefromthought
well, here is a thought: how much do YOU get paid for promoting ANTI-SCIENCE propaganda and pushing ANTI-SCIENCE beliefs?

Based upon the studies that I linked, we can truthfully say that there is likely a connection between YOUR anti-science posts and big business/big oil as well as the anti-agw political crowd

What I want to know is: considering they are making BILLIONS while YOU undermine science and do all the drudge work which ruins YOUR reputation as well as knowledge, why would you do something like that for a mere pittance that they pay you?

P.S. I don't agree with ANY of Obutthead-Obama policies. And I never liked the guy either. he's a moron, and I don't care HOW MANY watch lists I end up on for saying it

Sep 30, 2014
Unlike PPGTs, I don't get paid for posting. I get paid for working at my companies.
Unlike PPGTs, I don't get any money or talking points from the government.
Unlike PPGTs, I don't get any money or talking points from any political parties or political groups or organizations, big business, or any oil companies.
Unlike you captin I like to think independently. I don't live in my parents basement.

So captin, what policies differences do you have with Obama and the DNC? There must be a few..... unless you are paid to post their talking points.

Sep 30, 2014
Unlike you captin I like to think independently. I don't live in my parents basement
@freefromthoguht
transference?
LOL
and i require empirical evidence. of which I have given to you, and you have YET to provide back... so? That is not signs of inability to think "independently", it is a sign of intelligence... your idea of independent thought is to endorse any and all crackpot pseudoscience that comes down the pike... and to get paid to promote anti-science.
GIVEN that you have yet to provide ANY proof that agw is false, there is NO OTHER conclusion but to accept that you are paid to undermine science for big oil/big business.
so until you can show some actual reputable science that disproves AGW, then you are nothing but a paid anti-science hack.

who is the basement dweller now?
what policies differences do you have with Obama
I am pro-2nd amendment, pro-constitution. anti-obama care. good enough for you?

cjn
Sep 30, 2014
FTA:
"In a new study, a team led by Stanford climate scientist Noah Diffenbaugh used a novel combination of computer simulations and statistical techniques to show that a persistent region of high atmospheric pressure hovering over the Pacific Ocean that diverted storms away from California was much more likely to form in the presence of modern greenhouse gas concentrations."

This feels like a stretch to make a "link" between man-caused climate change and the California drought. Over the last century, the population of California has increased from 1.5M to 35.5M (2300% increase), which would correlate to a significantly greater drain on the local rivers and aquifers. One would imagine that this significantly compounds the effects of a temporarily-reduced rainfall, leading to the severe drought conditions.

Sep 30, 2014
Quite the coincidence that the RRR is setup over HAARP, maybe f'in with the Ionosphere isn't the smartest thing to do.

Does anyone know if there's been any other static blocking ridges occurring around the globe?

Sep 30, 2014
So how to tell if a poster is a Paid Progressive Government Troll, ask them which of Obama's or DNC policy they don't agree with. You ask them that question, a PPGT will not answer, because if they do they will lose a paycheck. They also fear they may then be audited by the IRS or investigated by the DOJ.


Apparently you figure yourself to be quite clever. That's funny!

Sep 30, 2014
@freefromthought
Unlike you captin I like to think independently.

That's obvious.

You thinking is independent from logic and common sense. Your posts are proof.

Unlike PPGTs, I don't get paid for posting. I get paid for working at my companies.


Is that where they make the tin foil hats?

Got any other stupid things to say?

Sep 30, 2014
Good note on CO2 and heat emission by forest fires:
Trees are releasing heat and CO2 stored fairly recently. Whereas CO2 released from fossil fuels was stored thousands of years ago.

In other words, due to time, on acts like a source, the other is a sink and a source.

Neat, huh?

Oct 04, 2014
What's really new is paying people to hate on science.

What isn't new, are stupid people who are incapable of an independent thought and don't know what science is.


I gotta hand it to ya, and here i though you couldn't take stupid to the next level if it stares you in the face due to the self inflicting embarrassing dumb comments you made on past climate articles.... but low and behold hahah... here you've done it again, but don't hold back...no no...
i'm getting a cold one for starters, and i fully i expect you to unleash your true inner buffoon on the next article (my bet is i won't be disappointed... ;) )... and to think they pay you to make you and them look stupid.... hahhahaha!!! o Man this is too funny... ! ! ! !

Oct 04, 2014
@freefromthought
Unlike you captin I like to think independently.

That's obvious.

You thinking is independent from logic and common sense. Your posts are proof.

Unlike PPGTs, I don't get paid for posting. I get paid for working at my companies.


Is that where they make the tin foil hats?

Got any other stupid things to say?


You bet they do, soon you will laugh again... him and 'ol "gory" has got that special something for self inflicting dumbness, but not just independently, they crave teaming up to see which of them can make the dumbest comment, or is it the split personality coming from the sockpuppet of one of them ? (so far i'm leaning towards gory poking himself into a continuous loop which is the funniest) either way... i just can't stop laughing.

Oct 04, 2014
Bulletin of the American Meteorological Society contradicts the above article. That collection of information about studies links all sorts of other events to climate change but not the California drought, which the Bulletin states is too variable to be definitively linked. The Bulletin also states that there is no appreciable trend downward in precipitation enough to link the drought to climate change. So, which studies are right?

In addition, over 7,000 years ago there was a similar drought event (including in California) that lasted for over 100 years. In addition, several times from that time to the not too distant past (drought of 1924, for example, and this cannot have been as a result of "anthropogenic climate disruption" or CO2 emissions) have multiple droughts as bad as the current one in California or worse. Any mention of any of that in the current slew of papers alluded to above? Feel free to one-rank accordingly for calling attention to other events. :-)

Oct 04, 2014
Think about how much science spending has been cut back by the political party trying to gain more power on this issue while the biggest carbon emitter is taking the lead in science.

Oct 04, 2014
Think about how much science spending has been cut back by the political party trying to gain more power on this issue while the biggest carbon emitter is taking the lead in science.


I try to practice brevity in my comments but your's lacks clarity.

Care to try again?


Oct 11, 2014
Absolutely it is caused by humans: by the high altitude DAILY chemical spraying of aluminum and sulfur particulates commissioned by the Federal government to manipulate the jet stream. They have caused a permanent high pressure area on the West Coast. Research geo-engineering, California chem-trails and "HAARP"!

Oct 11, 2014
Absolutely it is caused by humans: by the high altitude DAILY chemical spraying of aluminum and sulfur particulates commissioned by the Federal government to manipulate the jet stream. They have caused a permanent high pressure area on the West Coast. Research geo-engineering, California chem-trails and "HAARP"!


Please show a peer reviewed paper supporting your perspective? Your view is without any scientific support.

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