Accelerated Southwest Warming & Adaptation
- Accelerated Southwest Warming & AdaptationRecent warming in the southwestern United States has been among the most rapid in the nation, according to a recent report from United States Global Change Research Program (USGCRP). The report lists several impacts for the Southwest region, including increasing temperature, drought, wildfire, and invasive species, which are already accelerating the transformation of the landscape.One of the groups working on assessing these impacts at a local level is the Rocky Mountain Youth Corps (RMYC) in Taos, New Mexico. Last year, through the recommendation of TCP Presenter Bill Brown, RMYC enrolled in Climate Solutions University (CSU). This innovative online program, which includes The Climate Project as a partner, trains rural forest and water-dependent communities about climate adaptation. To receive additional resources from Climate Solutions University, visit www.mfpp.org/csu.Extreme Drought May Affect Much of World in Just 30 YearsAccording to a new analysis, climate change will likely make drought more widespread and severe over the next 30 years. Droughts are temporary dry periods caused by below-normal rain or snowfall. They are often accompanied by unusually high temperatures, and can be made worse by local wind patterns, changes in land use and other factors. Drought is one of the most disruptive types of extreme weather, affecting agriculture, water availability, tourism and wildlife.National Center for Atmospheric Research (NCAR) scientist Aiguo Dai used an ensemble of 22 climate models and a review of previous studies to update global drought projections. Dai found a long-term drying trend over much of the world's surface from 1900 to 2008, which was largely driven by increases in temperature. Models relying on the best available emission scenarios project increased drying in just the next 30 years, with the worst impacts in the western U.S., Central America, western South America, much of Africa, southern Europe, the Middle East, Southeast Asia, and southern Australia. "If the projections in this study come even close to being realized," Dai said, "the consequences for society worldwide will be enormous." The study was published in the October 19, 2010 Early View of WIREs Climate Change.2010 Sea Ice Extent Third-Lowest on RecordDue to higher-than-normal sea surface temperatures and a series of storm fronts, September 2010 saw the third lowest extent of Arctic sea ice since satellite observations began in 1979. Since that time, sea ice extent has declined about 11% per decade.The remaining ice was younger than in most previous years. By the end of summer 2010, less than 60,000 square kilometers (23,000 square miles) of old ice (5 years or older) remained, compared to 2 million square kilometers (722,000 square miles) during the 1980s."All indications are that sea ice will continue to decline over the next several decades," said Mark Serreze, Director of the National Snow and Ice Data Center. "We are still looking at a seasonally ice-free Arctic in 20 to 30 years."Tianjin Talks Take Small Step Closer to Deal in CancunFrom October 4-9, over 2,300 participants including government delegates, representatives from business and industry, environmental organizations and research institutions from more than 176 countries met in Tianjin, China for the final negotiating session before COP 16 in Cancun. (The COPs, or "Conferences of the Parties," are annual meetings of the United Nations Framework Convention on Climate Change). The goal of the Tianjin meeting was to prepare for COP 16 by identifying issues of convergence and clarifying what can be accomplished in Cancun.During the weeklong negotiations, the delegates discussed a package of decisions they will need to finalize in Cancun. Components include a long-term shared vision, an adaptation framework, a technology transfer mechanism, mitigation efforts, key operational elements of climate finance (such as a new climate fund) and capacity building.At the close of the talks, UNFCCC Executive Secretary Christiana Figueres commented on the progress made: "This week has got us closer to a structured set of decisions that can be agreed [to] in Cancun. Governments addressed what is doable in Cancun, and what may have to be left to later."While disagreement persists on politically charged issues such as transparency, accountability and the future of the Kyoto Protocol, parties are aiming for a balanced package of decisions that delivers results in the short-term as well as sets the framework for long-term commitments. "There is no magic bullet," Christiana Figueres said earlier this year, "[but] it is in everyone's ultimate interest to accelerate action in order to minimize negative impacts on all."COP 16 will take place in Cancun, Mexico, November 29-December 10, 2010.Read more about the Tianjin climate talks:"At Tianjin climate gathering, governments come closer to defining what can be achieved at Cancun UN Climate Change Conference""Countries agree on next steps for upcoming UN climate change negotiations""Summary of Tianjin Climate Change Talks"Is Climate Change Accelerating the Global Water Cycle?Two new studies provide evidence that climate change is intensifying the global water cycle, with implications for food and water availability and the risk of extreme weather.For the first study, which was published in the Proceedings of the National Academy of Science of the United States of America (PNAS), scientists from the U.S. and India analyzed the discharge of freshwater from continents to the ocean over a 13-year period. Although the amount of discharge varied significantly on an annual basis, the scientists found that discharge increased 1.5% per year (540 km3, or 19 trillion cubic feet per year) from 1994-2006. The analysis also suggested that increased ocean evaporation related to a rise in sea surface temperature drove the discharge trend."In general, more water is good," said co-author James Famiglietti. "But here's the problem: Not everybody is getting more rainfall, and those who are may not need it. What we're seeing is exactly what the Intergovernmental Panel on Climate Change predicted."The second study, published in Nature, focused on evapotranspiration (the movement of water from soils and plants to the atmosphere). Like freshwater discharge, worldwide evapotranspiration rates significantly increased from 1982-1997. Since 1998, however, evapotranspiration has stayed steady or potentially decreased. The increase appears to have been halted by a lack of soil water, particularly in Africa and Australia. You can read the PNAS paper, which was published September 29. The abstract of the Nature paper, published online on October 10.Both teams of scientists warn that the trends, as well as the proposed reasons for those trends, should be "interpreted with caution" because they were based on relatively short-term data sets."We didn't expect to see this shift in evapotranspiration over such a large area of the Southern Hemisphere," said co-author Beverly Law. If the soil water deficit is indeed related to human-made climate change, the world may experience reduced plant productivity and accelerated warming of the land surface as carbon emissions continue to climb.Carbon Dioxide is Earth's ThermostatTwo studies published this month in Science and Geophysical Research Letters find that, although CO2 is a relatively small component of our atmosphere, it acts like a thermostat by maintaining earth's temperature . The finding clarifies the relationship between CO2 and other greenhouse gases and confirms the contribution of CO2 to climate change.Scientists from NASA's Goddard Institute for Space Studies (GISS) used a model based on well-understood physical processes to assess the relative contribution of greenhouse gases and other "absorbers" (e.g., black carbon) to the greenhouse effect. Their results suggest water vapor and clouds account for about 75% of the greenhouse effect, whereas CO2 (from all sources) accounts for about 20%.The team then examined whether doubling the CO2 in the atmosphere from 1980 levels would change its relative importance. Surprisingly, the answer was no. The model suggested that the magnitude of the greenhouse effect changes when more CO2 is added to the atmosphere, but the relative contribution of each gas remains the same.A second team from GISS found that water vapor and clouds dominate the greenhouse effect because they amplify the warmth generated by CO2. But because water vapor and clouds are so sensitive to changes in temperature, they are also dependent on that CO2-driven warmth. As Andrew Lacis, the lead author on one of the studies puts it, CO2 and some of the other greenhouse gases "provide the temperature environment that is necessary for water vapor and cloud feedback effects to operate," making CO2 the "thermostat" of earth's climate."Humans are at a difficult crossroad," writes Lacis. "Carbon dioxide is the lifeblood of civilization as we know it. It is also the direct cause fueling an impending climate disaster. There is no viable alternative to counteract global warming except through direct human effort to reduce the atmospheric CO2 level."