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For more information on these science news and feature story tips, please contact the public information officer at the end of each item at (703) 292-8070. Editor: Josh Chamot Contents of this News Tip:
Soot Contributes to Droughts and Floods in ChinaA new climate study has found that soot particles composed of black carbon and other pollutants are causing precipitation and temperature changes in China and may be partially responsible for the increased floods and droughts in the region over the past several decades. In research funded by the National Science Foundation (NSF) and NASA, Surabi Menon of both NASA and Columbia University in New York, and her colleague, James Hansen of NASA's Goddard Institute for Space Studies in New York, have found that black carbon can affect regional climate by absorbing sunlight, which heats the air and thereby alters large-scale atmospheric circulation and the hydrologic cycle. The research appears in the September 27 Science. In recent years, northern China has suffered from increasingly severe dust storms, while increased rainfall in southern China is perhaps the largest change in precipitation since the year 950. Using a climate computer model and aerosol data from 46 ground stations in China, Menon and Hansen conducted four sets of computer simulations to monitor the effects of black carbon over China and India. From the simulations, the researchers found that increased amounts of soot over southern China could lead to the same pattern of southern flooding and northern droughts that has existed over the past several years. "If our interpretation is correct, then reducing the amount of black carbon or soot may help diminish the intensity of floods in the south and droughts in the northern areas of China, in addition to having human health benefits," Hansen said. Currently, the researchers are also studying a similar pattern over India. Black carbon or soot is generated from industrial pollution, traffic, outdoor fires and household burning of coal and biomass fuels. Emissions are large in China and India because cooking and heating are done with wood, field residue, cow dung, and coal, at a low temperature that does not allow for complete combustion. When soot absorbs sunlight it heats the air and reduces the amount of sunlight reaching the ground. The heated air rises and makes the atmosphere more unstable, bringing rainfall to regions that are heavily polluted. [Cheryl Dybas] Earthquake Study Produces New Depiction of Fault ZonesOn October 16, 1999, approximately 37 miles from Palm Springs, California, a magnitude 7.1 earthquake ripped through 28 miles of faults in the Mojave Desert. Because of the area's sparse population and development, the massive quake caused no major injuries or destruction. Yet, the "Hector Mine" event, named after a long-abandoned mine in the area, has produced a trove of information about earthquakes, faults, and ruptures for NSF-funded scientists at the Scripps Institution of Oceanography at the University of California at San Diego. These scientists, along with a colleague at the California Institute of Technology (Caltech), used satellite and radar data to uncover previously undocumented fault properties. The new findings include the first evidence that faults move backwards and indications that the material within faults is significantly different from surrounding material. Yuri Fialko of the Scripps Institution, the lead scientist on the study, says the results may lead to new ways of identifying potentially active faults, tracking when the last earthquake occurred in a fault zone, and better understanding the earthquake process. "Even small stress perturbations from distant earthquakes can cause faults to move a little bit, but it's only been known to cause this motion in a forward sense," said Fialko. "Here we observed the faults coming backwards due to relatively small stress changes, which is really quite unusual." The backward motion on the faults is caused by the different materials within the faults, rather than a frictional failure. According to Fialko, the results will guide new seismic studies to areas with contrasting fault material, and can then be used as a way of identifying potentially active faults. [Cheryl Dybas] Earthquake Testing Equipment Will Be Connected to National NetworkFive new NSF awards will provide advanced research and experimental equipment that will evaluate the impact of earthquakes. Researchers from across the United States are studying the effects of earthquakes in relation to building design, advanced materials and other measures that can minimize earthquake damage and loss of life. The awards are part of NSF's George E. Brown, Jr. Network for Earthquake Engineering Simulation (NEES). The high-speed Internet network, when completed in 2004, will remotely link researchers with tools for testing and improving the seismic design and performance of structures, utilities and other infrastructure. NSF will invest a total of about $82 million under NEES for new and upgraded equipment and the computer network that will connect the equipment facilities. Integration of the equipment is being managed by the University of Illinois at Urbana-Champaign. The equipment and network system will be managed by a consortium to be selected at a later time. The five new awards, totaling $15.5 million over two years, will fund construction, expansion and modernization of equipment at five U.S. universities, Cornell, Brigham Young, and Lehigh Universities and the Universities of California (San Diego) and Illinois (Urbana-Champaign). These awards complement the 11 equipment grants announced in early 2001 and provide new earthquake engineering testing capabilities for large-scale structural response and soil-foundation-structure interaction. [Amber Jones] For more information, see: Geometry Software Eases Math Education, VisualizationIn a recent survey conducted by the Center for Research on Information Technology and Organizations, math teachers rated The Geometer's Sketchpad as the most valuable software for students. The Geometer's Sketchpad, developed with support from NSF, provides colorful, graphic learning tools that make mathematics easier to teach and learn. The software is designed for an audience ranging from middle school students to research mathematicians and allows users to "draw" geometric figures and mathematical diagrams using virtual versions of the compass, the straightedge, and other standard mathematical tools. The visualization software and student guides were developed by Key Curriculum Press and its research affiliate KCP Technologies, Inc., of Emeryville, California, with funding from NSF's Small Business Innovation Research program. The latest version, Sketchpad 4.0, is the result of more than four years of research, development and field-testing in schools and universities across the country, and it incorporates powerful new tools for algebra, trigonometry and calculus. Version 4.03, released in August 2002, adds Macintosh OS X to the list of operating systems the software supports. [Amber Jones] For more information, see:
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