Readers may recall that Dr. John Christy found that irrigation increases temperatures measured in the central valley. This study finds it also increases rainfall and storms due to the additional available moisture. CO2 is not listed as being part of the equation, which makes the ‘extreme weather’ meme being pushed by alarmists even less likely. – Anthony
Central Valley irrigation intensifies rainfall, storms across the Southwest
UCI study finds that doubling of moisture in air has positive, negative effects
Irvine, Calif., Jan. 28, 2013 – Agricultural irrigation in California’s Central Valley doubles the amount of water vapor pumped into the atmosphere, ratcheting up rainfall and powerful monsoons across the interior Southwest, according to a new study by UC Irvine scientists.
Moisture on the vast farm fields evaporates, is blown over the Sierra Nevada and dumps 15 percent more than average summer rain in numerous other states. Runoff to the Colorado River increases by 28 percent, and the Four Corners region experiences a 56 percent boost in runoff. While the additional water supply can be a good thing, the transport pattern also accelerates the severity of monsoons and other potentially destructive seasonal weather events.
“If we stop irrigating in the Valley, we’ll see a decrease in stream flow in the Colorado River basin,” said climate hydrologist Jay Famiglietti, senior author on the paper, which will be published online Tuesday, Jan. 29, in the journal Geophysical Research Letters. The basin provides water for about 35 million people, including those in Los Angeles, Las Vegas and Phoenix. But the extra water vapor also accelerates normal atmospheric circulation, he said, “firing up” the annual storm cycle and drawing in more water vapor from the Gulf of Mexico as well as the Central Valley.
When the additional waves of moisture bump into developing monsoons, Famiglietti said, “it’s like throwing fuel on a fire.”
Famiglietti, an Earth system science professor in the School of Physical Sciences, and colleague Min-Hui Lo, a postdoctoral researcher at the University of California Center for Hydrologic Modeling who is now at National Taiwan University, painstakingly entered regional irrigation levels into global rainfall and weather models and traced the patterns.
“All percent differences in the paper are the differences between applying irrigation to the Central Valley and not applying it,” Famiglietti said. “That’s the point of the study – and the beauty of using computer models. You can isolate the phenomenon that you wish to explore, in this case, irrigation versus no irrigation.”
Famiglietti’s team plans to increase the scope of the work to track how major human water usage elsewhere in the world affects neighboring areas too. A better understanding of irrigation’s impact on the changing climate and water availability could improve resource management in parched or flooded areas.
About the University of California, Irvine: Founded in 1965, UCI is a top-ranked university dedicated to research, scholarship and community service. Led by Chancellor Michael Drake since 2005, UCI is among the most dynamic campuses in the University of California system, with more than 28,000 undergraduate and graduate students, 1,100 faculty and 9,400 staff. Orange County’s second-largest employer, UCI contributes an annual economic impact of $4.3 billion. For more UCI news, visit news.uci.edu.
Source: http://news.uci.edu/press-releases/central-valley-irrigation-intensifies-rainfall-storms-across-the-southwest-2/
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Bollocks, since when did the yanks have moonsons?
@Mark Nutley – have you never heard the expression “Cry me a river”? 😉
Lets see what the paper says but we need to keep things in focus. The landscape of the Valley is a giant erosional feature and the waster that did most of that work is long absent. Having increases in water, here and other SW basins, now quite dry, from what ever source is shall we say not abnormal except the the myopic thinking of those who believe they know that which they do not.
Truly odd, rain requires water vapor. Who wudda thunk it?
it is a sad commentary that people need this sort of study to counteract the “CO2 dun it.” crowd.
Iv’e heard some warmists claim that irrigation causes cooling. How does this play into the equation?
I am not at all convinced. This is pure conjecture.
Well they should pump even more water vapor into that area.Lake Mead is low so more run off is a good thing. I can already see it now, government Grants to install giant mist blowers in areas across the USA to control the weather. Weather is the one thing they can not control YET and tax. I would guess the government is paying big $$$ for the studies. They may impose new taxes on the farmers in CA for damages caused by irrigating crops releasing water vapor??
Dear Anthony,
So you are not going to post my comment and information about what conservatives knew and believed about climate change all the way back in 1981? If not, you are proving to be exactly what I feared: a person only interested in sharing information as long as it is the information you want to share. Please reconsider. This is important. I have some top journalists following my blog now, and you should also remain open to addressing all sides if you want to remain credible. http://www.buckyworld.me
REPLY: “top journalists” Wow, how transparent. And you’ve already stated in your diatribes that I’m not credible, so your silly carrot doesn’t work here. But the the answer is still no, because 1. it is off topic (as you have proven here with this comment on a totally unrelated thread). 2. all you want to do is build traffic for your website (proven, since you keep adding your tagline URL), all while calling people “deniers” and refusing to answer questions put to you here. What I am going to do is tag you for extra moderation attention, and if you do have something relevant to say that follows our policy it will be approved, all others automatically go to the bit bucket.
– Anthony
When i go to Spain in the boiling summer they have lovely water sprays in outside cafes that spray a fine mist every 30 secs, they soon cool the air.
Anything that increases moisture in the Great Basin is a GOOD THING! An occasional severe event is a small price to pay for a 15% increase in rain and 50ish% increase in runoff.
” Immigration increases ‘extreme weather’ “
There, that fixed that for you…….
http://www.telegraph.co.uk/news/worldnews/northamerica/usa/9832508/11-million-illegal-immigrants-could-be-offered-amnesty-pathway-in-US.html
.
So now we stop eating in order to save the planet? But if we stop growing food in California won’t it negatively impact all the migrant workers?
I don’t know about “extreme weather,” but I do know that when farmers plow their fields, the dark, moist soil makes lovely updrafts, and the hawks and buzzards circle there.
Can I have my grant money now? Or do I need to come up with a scenario where we need to abolish plowing? ( and/or eating?)
I guess all things are relative. I note that they claim: “If we stop irrigating in the Valley, we’ll see a decrease in stream flow in the Colorado River basin,”
Yet, at least in the southern Valley, virtually all the water comes from the Colorado river Basin (I am unfamiliar with the northern and mid central valley water sources). Given he also claims: “Moisture on the vast farm fields evaporates, is blown over the Sierra Nevada and dumps 15 percent more than average summer rain in numerous other states. Runoff to the Colorado River increases by 28 percent, and the Four Corners region experiences a 56 percent boost in runoff.”
The numbers do not add up. If much of the water, taken from the Colorado, is sent outside its basin, then stopping the taking of water from the Colorado would at least leave more in the basin. Location I can understand. Right now, Mexico gets precious little from the river since California (and other states) drain off most of it before it gets there. So perhaps he is saying that the US would see less, but the net affect to the entire system would seem to be an increase in the stream flow.
In the 1960’s there were 8 million hectares under irrigation. Latest info I could find makes that 280 million hectares. With H2O attributed to 70 to 96 percent of the greenhouse effect you might think this has an effect!!
I’m going to need to replace my BS meter. The needle just got wrapped around the peg 🙁
Interesting study of evaporation from the Central Valley. I hope some day they will get around to studying the effect of evaporation from high level fillings of the Salton Sink, which intermittently created a lake six times the size of the present Salton Sea. There is pretty good evidence for this happening less than a millenium ago. See
http://www.sci.sdsu.edu/salton/AncientLakeCahuilla.html
Is it the evaporation of the irrigation water while irrigating or transpiration evaporation from the greenery? Would subsurface drip irrigation solve this problem?
Mark Nutley says:
January 29, 2013 at 8:27 am
Bollocks, since when did the yanks have moonsons?
####
You should get out more. Maybe spend a few years in Phoenix Arizona.
“That’s the point of the study – and the beauty of using computer models.” ???
I’m soooo tired of models. Models belong on runways. I’d like to see these people get out from behind their damn desks and make some real world empirical measurements already.
philjourdan: Yet, at least in the southern Valley, virtually all the water comes from the Colorado river Basin (I am unfamiliar with the northern and mid central valley water sources).
Phil, I think you may be confusing “southern Valley” with “Southern California.”
@Juan Slayton – no, the Imperial valley. It is the southern part of the central valley. It is almost all either farmland or desert, and the farmland is irrigated through a series of canals, fed by – the Colorado River.
I thought ‘repurposing’ was a good thing in the great green world in which we live. Repurpose rainfall into stored water. Repurpose the stored water into electricity. Repurpose the used water for irrigation. Repurpose the irrigation water for food and atmospheric water vapor. Repurpose the water vapor into extra rainfall for the deserts of the southwest and great basin.
Where is the ‘gasoline on the fire’ in all of this. If you could take an area with 5″ – 15″ of rain a year and, with additional rainfall, have it become productive for growing more than cholla and sage brush it seems to me that would be a good thing. The word monsoon is used three times in the article, but always in a pejorative sense. Why? Ask the peoples of SE Asia how long they want to go without the monsoon. Or for that matter, anywhere in the world that people depend on regular waves of water for their very existence.
Uncontrolled flooding is not good. But flooding that is captured and stored and repurposed has been the basis of cultural and national growth since the rise of irrigation in ancient Persia. How insipid we have become as a people when we cower in the virtual closets of academia, sucking our collective thumbs and hoping that a celestial mommy will somehow make every challenge disappear so that we can come out and face the defeated bully of monsoon, or water vapor, or (gasp) a 1/2 degree rise in temperature.
Study: Irrigation increases ‘extreme weather’ in computer models /fixed
One wonders what happens in the…. ahem….. “real world”. When will these guys study reality and not computer games?
@Mark Nutley,
Actually, the American Southwest Desert does have a monsoon.
http://www.crh.noaa.gov/gjt/Weather_Info/monsoon.php
I used to ride my motorcycle in the summertime across SE Idaho, which is a combination of desert and irrigated farmland. I didn’t carry a thermometer but one wasn’t needed to detect a significant temperature difference when riding from one type of landscape to the other: The farmland felt a good 5 to 10 degrees cooler than the un-irrigated desert–so much so that we restricted our joyriding to farmland areas.
I’ve long held that irrigation simply supplies water to an inland hydrosphere that would otherwise be wasted by flowing directly into the Snake River and eventually into the Pacific, typically in a couple of early summer months with the spring runoff. That it alters our local climate during the summer is not surprising, but I submit the impact is beneficial by lowering temperatures and making this “desert” a more hospitable place to live. The irrigated crops grown here are also one of the biggest income generators for our state, and attempts at reducing such will be met with fierce resistance by our farmers as well as people who like Idaho potatoes–especially restaurants in the East. Idaho is also the #3 state for milk production, which is a surprise considering the small percentage of this state that is under cultivation.
I’ve also noticed that summer afternoon thunderstorms are common in the mountains to the east and to the north of us (Grand Tetons and Yellowstone, respectively) and while I haven’t used a comparative computer model, I’m sure the frequency and severity of these thunderstorms is increased by local irrigation. I’m happy our farmers are contributing to the local hydrologic cycle. And perhaps states to the east of us appreciate our contribution to their summer rainfall.
Those readers of this blog, who have the time, and don’t live in the SW US ( In which case they probably know this stuff already) might find it amusing to research where the moisture actually comes from that feeds the summer monsoonal flow!