Researchers Call for 'No-Regrets' Approach to Climate Warming

Jun 24, 2010 By Stephanie Doster
Map of the observed difference between the average annual U.S. temperatures (degrees F) for this century (2000 to 2009) and those of the last century (1900 to 1999). It is clear that the U.S. has been much warmer in this century than the last, particularly in the West, and even more so in the Southwest and headwaters of the Colorado River. (Source: NOAA)

(PhysOrg.com) -- The strategy, detailed in the journal Science, prepares people for a hotter and drier Southwestern U.S. through water conservation and the continued development of ways to harness energy from the sun, wind and Earth.

Two prominent climate experts, including one from the University of Arizona, are calling for a "no-regrets" strategy for planning for a hotter and drier western North America. Their advice: use water conservatively and continue developing ways to harness energy from the sun, wind and Earth.

Jonathan Overpeck, principal investigator with the Climate Assessment for the Southwest at the UA, and Bradley Udall, director of the Western Water Assessment at the University of Colorado, write in the June 25 issue of the that such an approach is necessary for coping with a wide range of projected future climate changes in the West and Southwest.

In their overview of shifting climate in the region, Overpeck and Udall cite published findings of prevalent signs of change: rising temperatures, earlier snowmelt, northward-shifting winter storms, increasing precipitation intensity and flooding, record-setting drought, plummeting Colorado River reservoir storage, widespread vegetation mortality and more large wildfires.

"The West, and especially the Southwest, is leading the nation in climate change - warming, drying, less late-winter snowpack and drought - as well as the impacts of this change," said Overpeck, a UA professor of geosciences and atmospheric sciences and co-director of the Institute of the Environment.

In the past 10 years, temperatures in almost all areas in western North America have surpassed the 20th century average, many by more than 1 or even 2 degrees Fahrenheit. The warming has decreased late-season snowpack, which serves as a water reservoir, as well as the annual flow of the Colorado River, the researchers said.

Those reductions, combined with the worst drought observed since 1900, haven't helped matters; water storage in Lakes Powell and Mead, the largest southwestern water reservoirs, fell nearly 50 percent between 1999 and 2004 and has not risen significantly since.

In addition to water, vegetation is feeling the effects of climate change. Work by UA's David Breshears and colleagues have already showed that more than 1 million hectares of piñon pine have died in the Southwest in the last few decades from a lethal combination of record-high temperatures and uncommonly severe drought. In addition, the frequency of large wildfires has increased as snowpack has decreased.

While researchers are confident that the higher temperatures and resulting changes in snowpack, Colorado River flow, vegetation mortality and wildfires are human-caused, they don't know whether the drought that has plagued the West for the last 10 years - the worst since record-keeping began - is because of humans, Overpeck said.

"It's critical to determine the causes of the observed change, including the drought, because then we will have a much improved ability to say what's coming next, in the future," Overpeck said.

To complicate issues, studies published to date suggest that Colorado River flow could continue to decrease by 20 percent by 2050, with severe implications for cities served by Colorado River water and for agricultural production.

"One thing is for sure," Overpeck said. "The best strategy now - the no-regrets strategy - is to prepare for a hotter and drier West, Southwest and Arizona, and to make sure we don't commit water to things now in ways that could make shortages in the future more difficult to deal with."

Fortunately, Overpeck said, scientists have a better understanding about potential future climate change in western North America than for many other regions around the globe, making it easier for policy makers to plan coping strategies.

The researchers also point to the region's potential wealth of solar, wind and geothermal renewable energy production.

"That offers a way to make up economically for the costs that will be incurred in adapting to the warmer, drier conditions," Overpeck said. "And it will have the side benefit of decreasing the chances, through reducing greenhouse gas emissions, for potentially greater human-caused ."

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deatopmg
2.5 / 5 (13) Jun 24, 2010
The journal "Science" publishes some impressive and sophisticated global warming articles. Problem is that ALL of these publications have used the known corrupted ("homogenized") temperature date from NASA/GISS, UEA/CRU, and NOAA.
GARBAGE IN/GARBAGE OUT!!
After 35 yrs I chose to leave AAAS because of their slanted, head in the sand stance on this subject.
thermodynamics
3.7 / 5 (9) Jun 25, 2010
deatopmg: Science and Nature have been the standard for well vetted articles. The fact that you show you don't have a clue as to the effort needed to tease signal out of noise in climate data is clear as you speak disparagingly of "homogenized" data while you probably have no idea what they did to homogenize it. Every signal has to be conditioned. We do that when we take temperatures using thermocouples, measure pressure as a result of the motion of a diaphragm, or measure a pressure differential as a proxy for flow. I am sure it is all a big conspiracy to you with thousands of scientists meeting in some clandestine version of Stone Henge and plotting the takeover of the planet by falsifying data. Give it a rest. You wouldn't know how to homogenize a data set if you had to. I bet you think smoothing data and statistical analysis are the devil's spawn.
marjon
5 / 5 (3) Jun 25, 2010
"No Regrets" for what?
It is always prudent for plan for the worst.
The SW USA as been a desert for quite some time.
patnclaire
2.8 / 5 (9) Jun 25, 2010
Let me see, thermodynamics. Would that data be from the same temperature and humidity sensors that are located next to air conditioners and on black tops and on top of black-tar-roofed industrial buildings?
When I see front page reports that these mis-placed sensors have been corrected...all of them, then I will have some professional regard for the data. Until then, it is just like smoke and mirrors.
And yes, I know how to extract usable data from raw, empirical data that contains a measure of noise.
Go ahead and exchange email with British and American professors about how to block any papers of mine from pet journals.
unrepentant is the operative word. When I see some contrite and humble self-flagellation then I will forgive and forget.
ubavontuba
1.7 / 5 (6) Jun 25, 2010
The journal "Science" publishes some impressive and sophisticated global warming articles. Problem is that ALL of these publications have used the known corrupted ("homogenized") temperature date from NASA/GISS, UEA/CRU, and NOAA.
GARBAGE IN/GARBAGE OUT!!
After 35 yrs I chose to leave AAAS because of their slanted, head in the sand stance on this subject.
Excellent! Also notice how these scientists use outdated data to support their contentions (1999 - 2004, really?). They're obviously using this data to ignore the fact that water storage has been increasing since - particularly in this past season (2009 - 2010). Also, the temperature map is similarly out of date. The temperate zones (worldwide) have actually been cooler than normal.

see: http://www.physor...722.html
ubavontuba
1.8 / 5 (5) Jun 25, 2010
"No Regrets" for what?
It is always prudent for plan for the worst.
The SW USA as been a desert for quite some time.
LOL! Excellent point.
JCincy
4.3 / 5 (4) Jun 25, 2010
It's all about water in the Southwest. Warmer climates and extended growing periods can actually be beneficial. But without fresh water, this offers little encouragement.

Investment in water conservation techniques (i.e., micro-irrigation) and desalination plants offer some of the better, long term solutions.
TegiriNenashi
1.7 / 5 (6) Jun 25, 2010
So given a dilemma between building more reservoirs, canals versus pissing off money onto GW scam, which one should we choose?
ubavontuba
1.5 / 5 (8) Jun 25, 2010
So given a dilemma between building more reservoirs, canals versus pissing off money onto GW scam, which one should we choose?
GW isn't a scam (in and of itself). It's just not necessarily a bad thing.
btt7338
3 / 5 (3) Jun 25, 2010
Without commenting on the truth of GW per se, this article is an excellent illustration of why people are skeptical about it. Why compare the average of 1900-1999 to 2000-2009? That seems a convenient set of ranges given that the article says there is currently a prolonged drought and then denies the notion that this drought is related to GW (and how would we even determine THAT with any kind of certainty). Why not compare 2000-2009 to 1900-1909? For all I know, the comparison is even more impressive...but I'm skeptical.
UFORocks
1 / 5 (3) Jun 27, 2010
Wouldn't it have made more sense to use a larger dataset for this research? This stuff (climate change) happens in cycles, and they're generally slow, right? So comparing two decades back-to-back isn't really going to give you a clear picture. I wonder what 2000-2009 would look like compared to the last 100 years.

It seems we've gone through a few climate cycles in the last hundred years or so, and each time someone is out preaching doom and gloom to the masses. Two that I can think of; The dust bowl years of the early 1900's, and the Ice Age scare of the 1970s.

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