Bet the farm.
Soon it won't be worth anything.
Study Says Droughts In The Southwest Could Become More Frequent
A federally funded study published Thursday argues the Southwest is moving into a drier climate, where droughts will be more frequent.
Researchers at the National Center for Atmospheric Research took data from 1979 to 2014 and identified broad storm patterns linked to wet weather. They noted the three patterns most connected to precipitation have become increasingly rare.
The leader of the study said in a press release: "A normal year in the Southwest is now drier than it once was. If you have a drought nowadays, it will be more severe because our base state is drier." (Video via CNN)
But 35 years of data may not be enough time to consider the shift to drier climates abnormal.
California, which is in the middle of a drought, is a good example. Scientists told The New York Times last April if you look at California's history, the state had droughts that lasted not just years but decades. In at least two cases during the last 1,200 years, droughts have lasted roughly two centuries. (Video via CBS)
One researcher told The New York Times: "We consider the last 150 years or so to be normal. But you don't have to go back very far at all to find much drier decades, and much drier centuries."
What could be worse for California may not be future dry-periods but that it developed its water infrastructure during an abnormally wet period from the mid-1970s to late 1990s when the state's population roughly doubled.
The National Center for Atmospheric Research's study supports other predictions of a drier climate in the Southwest. The authors said they hope their work will help water be conserved and dispersed strategically.
The Southwest is Swallowing Texas
As grass gives way to desert across the Lone Star State, the nation's fastest growing cities may be left high and dry.
The High Plains begin around the 100th meridian. It's where the verdant green of the Gulf of Mexico and Southeastern U.S. gives way to arid scrub, shortgrass and prickly pear cactus – where riders on horseback in the 1800s, nearly a century and a half before satellite mapping, were able to trace the border between these two regions as they split Oklahoma from the Texas Panhandle.
These days, the meridian's more or less paralleled to the east by Interstate 35, a steel-and-concrete vine that connects the Texas cities of Dallas, Fort Worth, San Marcos, Austin and San Antonio. Each ranks among the fastest-growing cities in America, their reservoirs reliably refreshed by rainwater.
Now, however, the border that once followed the 100th meridian – the threshold between lowlands and desert, water abundance and scarcity – is shifting east.
As climate change pushes the world's temperatures ever higher, the desert appears to be expanding, rushing toward the Louisiana border with each drought in a wave of tan and brown, then receding until the next dry spell. And with the region's population on track to double by 2050, the water that nearly 5 million people currently rely on for irrigation, electricity and energy development – not to mention hydration – could soon dwindle, with no grand solution in sight.
"People have this idea that every time they turn on the faucet, water ought to come out of the tap, and they have an idea that that will happen the rest of their life," says Jim Lester, president of the Houston Advanced Research Center, which studies energy and environmental issues. "We had towns in Texas in 2011 where they had to truck in water, they had to distribute it in bottles. If that problem is moving west to east, who's to say that isn't going to happen in Austin next time there's a severe drought?
"I-35, that's where the crisis is going to hit."
These days, the meridian's more or less paralleled to the east by Interstate 35, a steel-and-concrete vine that connects the Texas cities of Dallas, Fort Worth, San Marcos, Austin and San Antonio. Each ranks among the fastest-growing cities in America, their reservoirs reliably refreshed by rainwater.
Now, however, the border that once followed the 100th meridian – the threshold between lowlands and desert, water abundance and scarcity – is shifting east.
As climate change pushes the world's temperatures ever higher, the desert appears to be expanding, rushing toward the Louisiana border with each drought in a wave of tan and brown, then receding until the next dry spell. And with the region's population on track to double by 2050, the water that nearly 5 million people currently rely on for irrigation, electricity and energy development – not to mention hydration – could soon dwindle, with no grand solution in sight.
"People have this idea that every time they turn on the faucet, water ought to come out of the tap, and they have an idea that that will happen the rest of their life," says Jim Lester, president of the Houston Advanced Research Center, which studies energy and environmental issues. "We had towns in Texas in 2011 where they had to truck in water, they had to distribute it in bottles. If that problem is moving west to east, who's to say that isn't going to happen in Austin next time there's a severe drought?
"I-35, that's where the crisis is going to hit."
Dry Lake Mead?
50-50 Chance By 2021
What are the chances that Lake Mead, a key source of water for more than 22 million people in the Southwest, would ever go dry? A new study says it's 50 percent by 2021 if warming continues and water use is not curtailed.
"We were stunned at the magnitude of the problem and how fast it was coming at us," co-author Tim Barnett of the Scripps Institution of Oceanography said in a statement. "Make no mistake, this water problem is not a scientific abstraction, but rather one that will impact each and every one of us that live in the Southwest."
"It's likely to mean real changes to how we live and do business in this region," added co-author David Pierce, a Scripps climate scientist.
The experts estimated that the Colorado River system, which feeds Lake Mead and Lake Powell, is seeing a net deficit of nearly 1 million acre-feet of water per year — an amount that can supply some 8 million people. That water is not being replenished, they noted, and human demand, evaporation and human-induced climate change are fueling the growing deficit.
The system is already at half capacity because of eight years of drought.
"When expected changes due to global warming are included as well, currently scheduled depletions are simply not sustainable," Barnett and Pierce write in the study.
The two analyzed federal records of past water demand as well as calculations of scheduled water allocations and climate conditions.
Bucket being depleted
"The biggest change right now is taking more water from the bucket than we are putting into it," Barnett said.
Lake Mead straddles the Arizona-Nevada border. Aqueducts carry water from the system to Las Vegas, Los Angeles, San Diego, and other communities.
The researchers also noted that their estimates are conservative — in other words, the water shortage is likely to be even more dire than they estimate. The conservative approach included basing their findings on:
- The premise that warming effects only started in 2007, though most experts consider human-caused warming to have likely started decades earlier.
- Averaging river flow over the past 100 years, even though it has dropped in recent decades.
The study has been accepted for publication, possibly next month, in the peer-reviewed Water Resources Research, a journal of the American Geophysical Union.
Barnett and Pierce also estimated:
- A 10 percent chance that Lake Mead could be dry by 2014.
- A 50 percent chance that reservoir levels will drop too low to allow hydroelectric power generation by 2017.
The uncertainty about when and if the lake will run dry stems from the natural fluctuations of the Colorado River, which feeds the lake, Barnett said. In recent months the flow has been above average, he said, after years below average.
'At or beyond the sustainable limit'
The system could still run dry even if recently proposed mitigation measures are implemented, the researchers said.
The system could still run dry even if recently proposed mitigation measures are implemented, the researchers said.
The reduction in water levels due to drought on Lake Mead can be seen by the white ring around the shore at Hoover Dam in this photo from July 21, 2006.
"Today, we are at or beyond the sustainable limit of the Colorado system," the study concludes. "The alternative to reasoned solutions to this coming water crisis is a major societal and economic disruption in the desert southwest; something that will affect each of us living in the region."
Lake Mead, which was created when Hoover Dam was buit, provides 90 percent of Las Vegas' water.
Scott Huntley, a spokesman for the Southern Nevada Water Authority, said his agency overseeing the Las Vegas area's water was concerned about reliance on Lake Mead as the major source for Las Vegas and officials were seeking alternate sources.
"While we wholeheartedly support the authors' call for greater urban water conservation, it is important to also remember that agriculture uses four-fifths of the Colorado River's flows, so meaningful solutions cannot be borne solely by urban users," he added.
Reuters contributed to this report.
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Climate: A New Study Finds That Global Warming Could Dry Out the Southwest
It’s not the heat that might get us with climate change—it’s the humidity, so to speak. The risk of sea level rise due to melting land ice is one of the most recognized—if controversial and hard to predict—threats posed by global warming. Other potential impacts from global warming include increasingly powerful storms and floods of the sort that have ravaged Australia this past month and a half (while recognizing scientists can’t yet fingerprint individual weather events as caused by warming).
But as climate change create havoc from too much water, parts of the world could end up suffering from too little water. That’s the conclusion of a new study released today by the Stockholm Environment Institute (SEI), an environmental research organization based, unsurprisingly, in Stockholm (Download a PDF of the report here.) The report found that the already dry states of the American Southwest—Arizona, California, Nevada, New Mexico and Utah—will face a major water shortfall over the next century just based on population and income growth alone. (The region has long been one of the fastest-growing in the U.S., in part because of the hot and dry weather.) But climate change could make the situation much, much worse. According to the SEI study, global warming could increase the long-term water shortfall by a quarter, adding an additional 282 million to 439 million acre feet of water to the 1.815 billion acre feet shortfall already expected. Based on the price of adding reservoir capacity in California, meeting the baseline water shortage could cost $2.3 trillion—yes, that’s “trillion” with a “t”—plus $353 billion to $549 billion if climate change is factored in. Higher water prices would make adaptation even more expensive—assuming additional water could be found at all in a drier future. As Frank Ackerman, the director of the Climate Economics Group at SEI-U.S. and a co-author of the study, said in a statement:
As the report points out, water shortages in the Southwest aren’t anything new, and so far we’ve managed to adapt to a dry climate even as cities like Las Vegas and Phoenix essentially rise out of the desert. But even before climate change has really become a factor, water supplies have already dropped to scary levels throughout the region. Water levels at Lake Mead, the manmade reservoir that feeds Las Vegas, have fallen drastically in recent months, while California has endured a three year-long drought that only recently has shown signs of ending. The Southwest has been accustomed to unlimited growth in cities and exurbs along with unlimited water for irrigated agriculture, but the day may come soon when a choice will have to be made between the city and the farm. I visited Lake Mead myself in 2008, and even then, the falling water levels did not bode well for the future of Las Vegas and the rest of the Southwest:
Lake Mead’s level is currently at 1,093 ft.—below the official drought point.
Even scarier might be the impact of climate drying on agriculture. Food prices are already at a record high—thanks to extreme weather events, rising demand in developing nations and likely some speculation—but in the decades to come farmers will need to feed billions more, many of them wealthier and demanding more meat. (One lb. of animal protein can require 100 lbs. of grain to produce, and thousands of gallons of water.) 70% of the world’s freshwater is used for irrigation, so when we talk about water-related climate problems, we’re really talking about farming. Even more worrying, agriculture in much of the world has already been propped up by groundwater pumped from aquafiers—but half the planet lives in areas where water tables are falling due to overdepletion. According to the World Bank, 15% of India’s food supply is grown with water produced by aquafiers—and they don’t recharge quickly. “That means 175 million people in India are being supported by food grown with groundwater,” says Lester Brown, the founder of the Earth Policy Institute and a long-time pessimist on farming and climate. In China, that figure could be as high as 130 million.
What happens if agriculture begins to wilt and food prices rise? Governments can fall—as Egypt’s nervous government knows, where high food prices have been one factor in that country’s unprecedented mass protests. Other Middle Eastern countries—already under stress by the combined effect that population growth and climate change may be having on local agriculture—are rightfully worried that they could be next. “You could see governments falling left and right, food riots and instability on a scale we have not seen before,” says Brown. “Desperate people do desperate things.”
I doubt you’re likely to see the sunburned citizens of San Diego or Reno take to the streets any time soon over the price of bread. The U.S., after all, should have no trouble feeding itself—even though over 50 million Americans live in food insecure households, that has more to do with structural problems than lack of production. But an ever drier Southwest is one that truly will face an existential threat in the decades ahead—and the rest of us might not be far behind.
More from TIME on water and climate:
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