X-Message-Number: 29398 From: Date: Sat, 07 Apr 2007 00:34:22 -0500 Subject: Southwest USA Climate Change Threatens Alcor & Its Patients --_----------=_1175924062222162 Content-Disposition: inline http://www.azcentral.com/arizonarepublic/news/articles/0406climate-report0406.html# Southwest could become Dust Bowl, study warns Shaun McKinnon The Arizona Republic Apr. 6, 2007 12:00 AM Rising temperatures will fuel longer and more intense droughts across Arizona and the Southwest, according to a new climate-change report that warns of conditions not seen since the 1930s Dust Bowl. What sets the report apart from others that have painted an equally bleak future is its assertion that changes already have begun, that the state's 12-year-old drought may reflect what scientists call the new climate for the Southwest. The study, published today in the journal Science, arrives along with a broader assessment of global warming by teams of international scientists. That report, set for release this morning in Belgium, charts a litany of ecologic and economic threats posed by greenhouse gases and concludes that, in many areas, the threats have now become real. Both reports attempt to inject urgency into the contentious discussion of climate change, with authors arguing that their dire forecasts will come true unless governments move to reduce emissions from automobiles, power plants, factories and other sources of carbon dioxide. A study by the Intergovernmental Panel on Climate Change, which produced the international report out today, concluded earlier this year that humans are almost certainly responsible for much of the planet's higher temperatures. "It's important for Americans to realize we're not going to escape the big impacts, whether it's more hurricanes and sea-level rise in the East or drought here in the West," said Jonathan Overpeck, director of the University of Arizona's Institute for the Study of Planet Earth. "These things are going to challenge business as usual and quality of life. This should be a wake-up call." The drought study startled some scientists with its confidence level. Researchers from several universities and the National Center for Atmospheric Research used 19 models, some dating to 1860, and found that all but one pointed to the same conclusions: The Southwest will turn drier, perhaps as soon as 2040, and will grow drier through this century as less rain and snow falls. "We're really talking about something we haven't seen since Europeans came to North America," said Overpeck, who has studied climate change and drought for many years. "We might already be in this trend toward greater aridity in the Southwest. The end result will be average conditions that will be like the worst drought of the 20th century." Effects on Arizona's water The drought study did not look at another effect of climate change, the shortening winter snow season and shrinking runoff supply. Scientists have spotted that trend in higher elevations of the Rocky Mountains and the Pacific Northwest and expect it to spread. Western states rely heavily on runoff to meet water needs. A permanent change in flow on the Colorado River could cause shortages among users and reduce the amount of hydroelectric power available to cool the warming region. In Arizona, most of the serious effects of climate change link directly to water and drought. With less rain and snow, forests dry up, leading to increased fire danger and more frequent insect invasions. As runoff decreases into streams and rivers, wildlife habitat disappears and the wildlife follow. The heat itself will worsen air quality, allowing greater buildup of ozone as average July and August temperatures climb by as much as 9 degrees by 2070. As the dominoes fall, the damage spreads. A bark beetle invasion near Winslow earlier this decade virtually wiped out a stand of pine trees, which destroyed habitat for some species. Biologists fear the entire ecosystem will change in the coming years. "The species we have today have evolved over several hundred years under certain climatic conditions, in the presence of other species," said Lisa McNeilly, northern Arizona program director for the Nature Conservancy and a former researcher at the Pew Center on Global Climate Change. "When you start changing those things quickly, it's hard to predict what will happen," she said. "We're putting things at risk we hold dear if we don't do something to reduce emissions." Evidence of change Although both the drought study and the larger international report say climate change already has affected the environment, scientists say they still need time to confirm that some of what is happening is not just cyclical changes. "Some of what's happening with the early snowmelts could be due to variations based on ocean circulation," said Gregg Garfin, project manager for the UA institute. "But there's a pretty large fraction that can't be explained that way, and we think that's due to increasing temperatures." Evidence of climate change will help scientists understand it better, said Netra Chhetri, an Arizona State University researcher who worked on the international study. "Until recently, a lot of focus in the study of climate change has been driven by models," said Chhetri, who also teaches classes on climate change. "But recently, some of us are beginning to look into actual indicators, things like early arrival of growing seasons or early flowering of trees." More real evidence will probably drive discussion of the topic beyond universities. Attitudes already have changed in recent years. A survey of Arizonans by the polling company Public Opinion Strategies indicated that two-thirds of those asked believe enough evidence exists about the threat of global warming to spur government action. Only 15 percent in the poll thought the issue had been exaggerated. The next section of the international report, due next month, will focus on what countries and individuals can do to slow climate change and adapt to its effects. --_----------=_1175924062222162 Content-Disposition: inline Content-Type: text/html; charset="iso-8859-1" [ AUTOMATICALLY SKIPPING HTML ENCODING! ] Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=29398