The study by Cornell University, University of Arizona and U.S. Geological Survey researchers will be published in a forthcoming issue of the American Meteorological Society’s Journal of Climate.
“For the southwestern U.S., I’m not optimistic about avoiding real megadroughts,” said Toby Ault, Cornell assistant professor of earth and atmospheric sciences and lead author of the paper. “As we add greenhouse gases into the atmosphere – and we haven’t put the brakes on stopping this – we are weighting the dice for megadrought conditions.”
As of mid-August, most of California sits in a D4 “exceptional drought,” which is in the most severe category. Oregon, Arizona, New Mexico, Oklahoma and Texas also loiter between moderate and exceptional drought. Ault says climatologists don’t know whether the severe western and southwestern drought will continue, but he said, “With ongoing climate change, this is a glimpse of things to come. It’s a preview of our future.”
Ault said that the West and Southwest must look for mitigation strategies to cope with looming long-drought scenarios. “This will be worse than anything seen during the last 2,000 years and would pose unprecedented challenges to water resources in the region,” he said.
In computer models, while California, Arizona and New Mexico will likely face drought, the researchers show the chances for drought in parts of Washington, Montana and Idaho may decrease.
Beyond the United States, southern Africa, Australia and the Amazon basin are also vulnerable to the possibility of a megadrought. With increases in temperatures, drought severity will likely worsen, “implying that our results should be viewed as conservative,” the study reports.
“These results help us take the long view of future drought risk in the Southwest – and the picture is not pretty. We hope this opens up new discussions about how to best use and conserve the precious water that we have,” said Julia Cole, UA professor of geosciences and of atmospheric sciences.
The study, “Assessing the Risk of Persistent Drought Using Climate Model Simulations and Paleoclimate Data,” was also co-authored by Julia E. Cole, David M. Meko and Jonathan T. Overpeck of University of Arizona; and Gregory T. Pederson of the U.S. Geological Survey.
The National Science Foundation, National Center for Atmospheric Research, the U.S. Geological Survey and the National Oceanic and Atmospheric Administration funded the research.
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The full paper is available here:
https://cornell.app.box.com/Megadrought/1/2369732445/20394648023/1
Dust Bowl II. It isn’t as if it didn’t happen before.
not likely to repeat for 500 to 1000 years. rains are slowing returning to NTexas, panhandles TexOk, Okie, and Kansas.
The recent history of at least half of Texas is hardly “dry as a bone”. DFW area averages around 40 inches of annual rainfall. The problem is, for Texas and most of the West, that recent history may represent an unusually wet period. Long-term history of the West includes long periods of severe drought, which wiped out some of the ancient cultures. Read “Cadillac Desert” if you’re interested in the subject. Fascinating book.
I could not easily read past “Due to Global Warming” but I did. This study is dishonest. The 30 years comes from acknowledging the cycle of cooler and drier that seems to be heading our way. The dry will increase temperatures in some areas due to lack of water to soak soak up latent heat of vaporization.
Key phrase “in computer models”.
Why exactly are we even talking about this when it’s based on computer models that cannot even accurately predict weather a week away? The talk is like…”IT WILL HAPPEN IF WE DON’T ACT!!” “The climate models say so, so be afraid….be very afraid!!”
Ian W August 28, 2014 at 10:12 am
So the IPCC accepted ‘pause’ is not accepted by these researchers? The missing heat i.e. heat that is not in the atmosphere – is actually in the deep ocean; yet from there with some kind of ‘teleconnection (an effect without a known mechanism) this crytpo-heat is causing ‘megadrought’ in the models. They do not appear to agree with each other too well on their excuses for no warming, as their ‘team’ agrees that warming has not happened; yet they continue to churn out forecasts based on warming and declare the last year the hottest year ever! while making excuses for not warming. How can they continue to call it ‘settled science’?
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I am with you here sort of. But the claim, is that changing ocean circulation is pushing it down. This is a known part of the ENSO process. That is, we know that the east bound winds during La Nina bring up cool water from the west, and over cloudless skies, the water warms and gets plunged deep on the western Pacific. Warm water can and does go down deep.
That said, this has nothing to do with CO2 causing it.
I read in a National Geographic back in the 60s that the people using the Oregon Trail passed through land that was semi-desert and unusable for agriculture. The article mentioned that “a change in climate” brought enough rain that the land became arable. Who is familiar with that part of the world and can tell us if the drought is bringing back the conditions of Oregon Trail days?
Ian M
It’s too bad for the Warmunists that IPCC’s AR5 report explicitly stated there is insufficient evidence to show ANY statistically significant increase in global drought trends for the past 60+ years :
“In summary, the current assessment concludes that there is not enough evidence at present to suggest more than low confidence in a global-scale observed trend in drought or dryness (lack of rainfall) since the middle of the 20th century due to lack of direct observations, geographical inconsistencies in the trends, and dependencies of inferred trends on the index choice. Based on updated studies, AR4 conclusions regarding global increasing trends in drought since the 1970s were probably overstated. However, it is likely that the frequency and intensity of drought has increased in the Mediterranean and West Africa and decreased in central North America and north-west Australia since 1950.”
Until CAGW has a stake driven through its cold and evil heart, these propaganda “studies” will be churned out with much hand-waving and consternation.
Climate Happens (TM)
A ‘study’ like this is almost certain to usher in a period of unusually wet weather ……
If California wants to really deal with its rather consistent drought status perhaps they could consider retrieving some of the the tens of billions they are currently ratholing on their incredible high speed rail to nowhere and use the funds to start building water infrastructure again. It might also help if they quit flushing their desperately needed water supply into the the ocean in a futile attempt to save a bait fish.
Southwest may face ‘megadrought’ this century.DOH!
AFAIK The Southwest may face ‘megadrought’ almost any century.
Are they saying that at some period during the “hockey stick” past the southwest went through centuries that may not have had to face megadrought? And how would “may not have had to face the threat of megadroughts” be established? Just because they didn’t have a drought doesn’t mean the people may not have had to face the threat of one.
Do they have supporting data indicating the periods when the Southwest may not face ‘megadrought’ for some century or is this just more Penn State tree ring science?
Seems you’ve tied yourself up into a bit of semantic pretzel ridiculing the study.
Why don’t you send your questions into the authors and see if you get a reply? Or better still, simply think a little about the careful framing of Ault’s statement “.. climatologists don’t know whether the severe western and southwestern drought will continue”, but “With ongoing climate change, this is a glimpse of things to come. It’s a preview of our future.”
Do you have a scientifically framed criticism of his formulation?
Zeke August 28, 2014 at 1:11 pm
Aquifer levels over time are an unknown. Grace satellite measurements are worthless. Would you shut down the rice growers in India because Grace says the aquifers are dropping?
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Are you talking about ame or the UN and the US EPA?
I’M pretty sure I wouldn’t but,
That may not be the same answer all around./sarc
seeing as how drought here in the SW ruined the lives of Indians a thousand (+) years ago pretty good gamble that we will have another. Or maybe it will be wetter. A lot of you will notice the science in my post and recognize it as being grant worthy.
So… the guys at Cornell don’t factor in the cold PDO…. seems very similar to the last cold PDO where Cali drys out… not sayin’ that’s absolutely it.. but just sayin… cold PDO means dry Cali… on avg…. an el nino would help.. temporarily… plus.. more people in Cali than last cold PDO using water.. it has to come from somewhere…
Where can one make book on this prediction?
“Due to global warming, scientists say, the chances of the southwestern United States experiencing a decade long drought is at least 50 percent, and the chances of a “megadrought” – one that lasts over 30 years – ranges from 20 to 50 percent over the next century.”
The present global warming is milder than the MWP. The megadrought in southwestern US during the MWP is worse and lasted hundreds of years. And this is not computer models but geologic evidences.
Which doesn’t disprove the Scientist’s statement as you quoted it.