Featured Research

from universities, journals, and other organizations

Climate Change Means Shortfalls In Colorado River Water Deliveries

Date:
April 27, 2009
Source:
University of California - San Diego
Summary:
Researchers have found that currently scheduled water deliveries from the Colorado River are unlikely to be met if human-caused climate change reduces runoff in the region.

Scheduled deliveries of water from Lake Mead, created by Hoover Dam, could be missed 60 to 90 percent of the time by midcentury if human-caused climate change continues to make the region drier.
Credit: US Bureau of Reclamation

The Colorado River system supplies water to tens of millions of people and millions of acres of farmland, and has never experienced a delivery shortage. But if human-caused climate change continues to make the region drier, scheduled deliveries will be missed 60-90 percent of the time by the middle of this century, according to a pair of climate researchers at Scripps Institution of Oceanography, UC San Diego.

"All water-use planning is based on the idea that the next 100 years will be like the last 100," said Scripps research marine physicist Tim Barnett, a co-author of the report. "We considered the question: Can the river deliver water at the levels currently scheduled if the climate changes as we expect it to. The answer is no."

Even under conservative climate change scenarios, Barnett and Scripps climate researcher David Pierce found that reductions in the runoff that feeds the Colorado River mean that it could short the Southwest of a half-billion cubic meters (400,000 acre feet) of water per year 40 percent of the time by 2025. (An acre foot of water is typically considered adequate to meet the annual water needs of two households.) By the later part of this century, those numbers double.

The paper, "Sustainable water deliveries from the Colorado River in a changing climate," appears in the April 20 edition of the journal Proceedings of the National Academy of Sciences.

The analysis follows a 2008 study in which Barnett and Pierce found that Lake Mead, the reservoir on the Colorado River created by Hoover Dam, stood a 50-percent chance of going dry in the next 20 years if the climate changed and no effort was made to preserve a minimum amount of water in the reservoir. The new study assumes instead that enough water would be retained in the reservoir to supply the city of Las Vegas, and examines what delivery cuts would be required to maintain that level.

"People have talked for at least 30 years about the Colorado being oversubscribed but no one ever put a date on it or an amount. That's what we've done," said Barnett. "Without numbers like this, it's pretty hard for resource managers to know what to do."

Barnett and Pierce also point out that lakes Mead and Powell were built during and calibrated to the 20th century, which was one of the wettest in the last 1,200 years. Tree ring records show that typical Colorado River flows are substantially lower, yet 20th Century values are used in most long-term planning of the River. If the Colorado River flow reverts to its long-term average indicated by the tree rings, then currently scheduled water deliveries are even less sustainable.

Barnett and Pierce show that the biggest effects of human-induced climate change will probably be seen during dry, low-delivery years. In most years, delivery shortfalls will be small enough to be manageable through conservation and water transfers, they estimate. But during dry years there is an increasing chance of substantial shortages.

"Fortunately, we can avoid such big shortfalls if the river's users agree on a way to reduce their average water use," said Pierce. "If we could do that, the system could stay sustainable further into the future than we estimate currently, even if the climate changes."

Note to broadcast and cable producers: UC San Diego provides an on-campus satellite uplink facility for live or pre-recorded television interviews. Please phone or e-mail the media contact listed above to arrange an interview.


Story Source:

The above story is based on materials provided by University of California - San Diego. Note: Materials may be edited for content and length.


Cite This Page:

University of California - San Diego. "Climate Change Means Shortfalls In Colorado River Water Deliveries." ScienceDaily. ScienceDaily, 27 April 2009. <www.sciencedaily.com/releases/2009/04/090420182203.htm>.
University of California - San Diego. (2009, April 27). Climate Change Means Shortfalls In Colorado River Water Deliveries. ScienceDaily. Retrieved July 29, 2014 from www.sciencedaily.com/releases/2009/04/090420182203.htm
University of California - San Diego. "Climate Change Means Shortfalls In Colorado River Water Deliveries." ScienceDaily. www.sciencedaily.com/releases/2009/04/090420182203.htm (accessed July 29, 2014).

Share This




More Earth & Climate News

Tuesday, July 29, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Baluchistan Mining Eyes an Uncertain Future

Baluchistan Mining Eyes an Uncertain Future

AFP (July 29, 2014) Coal mining is one of the major industries in Baluchistan but a lack of infrastructure and frequent accidents mean that the area has yet to hit its potential. Duration: 01:58 Video provided by AFP
Powered by NewsLook.com
Asteroid's Timing Was 'Colossal Bad Luck' For The Dinosaurs

Asteroid's Timing Was 'Colossal Bad Luck' For The Dinosaurs

Newsy (July 28, 2014) The asteroid that killed the dinosaurs struck at the worst time for them. A new study says that if it hit earlier or later, they might've survived. Video provided by Newsy
Powered by NewsLook.com
The Carbon Trap: US Exports Global Warming

The Carbon Trap: US Exports Global Warming

AP (July 28, 2014) AP Investigation: As the Obama administration weans the country off dirty fuels, energy companies are ramping-up overseas coal exports at a heavy price. (July 28) Video provided by AP
Powered by NewsLook.com
Raw: Sea Turtle Hatchlings Emerge from Nest

Raw: Sea Turtle Hatchlings Emerge from Nest

AP (July 27, 2014) A live-streaming webcam catches loggerhead sea turtle hatchlings emerging from a nest in the Florida Keys. (July 27) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins