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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: Cheryl Dybas Contents of this News Tip:
NSF AIRCRAFT TESTS NEW CLEAR-AIR TURBULENCE SENSORScientists aboard an Electra research aircraft owned by the National Science Foundation (NSF) and operated by the NSF-supported National Center for Atmospheric Research (NCAR) in Boulder, Colorado, will attempt to detect dangerous clear-air turbulence using an new onboard sensor during test flights over the Rocky Mountain region between March 23 and April 10. The Doppler lidar sensor uses laser beams to track the motions of natural aerosol particles as they swirl in turbulent air several miles ahead of the plane. Because turbulence is short-lived and invisible to both the eye and radar, it is difficult to detect and forecast, say scientists. During the experiments, the Electra crew will seek out turbulent areas predicted by meteorologists. Unlike radar, which uses radio waves, the lidar sensor will shoot a laser beam forward into expected turbulence in the aircraft's flight path. Dust particles and aerosols will reflect the laser beam back to the plane, characterizing the turbulent air motions ahead. When the plane encounters the choppy air, its response will be measured and the atmospheric turbulence inferred will later be compared to that detected in the forward-looking lidar data. If the two mesh, the lidar could prove useful on commercial aircraft for detecting turbulence in time for pilots to instruct passengers and crew to be seated and fasten their seat belts before injuries occur. [Cheryl Dybas] EL NINO RAINS BRING BONANZA OF SPRING FLOWERSThe news related to this year's El Niño isn't all bad, according to scientists who study desert annuals -- wildflowers that bloom once a year. The researchers are having a field day in California's East Mojave Desert at Anza-Borrego State Park, an arid locale east of San Diego. There, the driest parts of California's desert are covered with wildflowers this spring in what some botanists are calling a flower-lover's bonanza. NSF-funded biologist Phil Rundel of the University of California at Los Angeles is just one of many such scientists combing the desert sands of Anza-Borrego this month. "Desert annuals have been an important group for study by many ecologists, including population biologists looking at life history adaptations," says Rundel. "But this year, the picture is even more interesting. El Niño conditions are providing unusual conditions which have produced abundant germination and seed set of both common and rare desert annuals." In other words, flowers, flowers, and more flowers carpeting the usually drab desert ground with knock-your-eyes-out pinks, reds, oranges and yellows, as far as the eye can see. "We hope to soon have a better understanding of the cues for flower germination in winter-rainfall deserts like the Mojave and the Colorado," says Rundel. In the meantime, Anza-Borrego's riotous color is a feast for winter-weary eyes. [Cheryl Dybas] SCIENTISTS DISCOVER MASSIVE JET STREAMS INSIDE THE SUNNSF-supported scientists affiliated with California's Stanford University have discovered "jet streams" or "rivers" of hot, electrically charged gases called plasmas flowing beneath the surface of the sun. They have also found features similar to trade winds that transport gas beneath the sun's fiery surface, and learned that the entire outer layer of the sun, to a depth of at least 15,000 miles, is slowly but steadily flowing from its equator to its poles. "We have detected motion similar to the weather patterns in Earth's atmosphere," says researcher Jesper Schou of Stanford. "Moreover, in what is a completely new discovery, we have found a jetlike flow near the poles. This flow is totally inside the sun. It is completely unexpected, and cannot be seen at the surface." Adds scientist Philip Scherrer, also of Stanford, "These polar streams are on a small scale, compared to the whole sun, but they are still immense compared to atmospheric jet streams on Earth." Ringing the sun at about 75 degrees latitude, they consist of flattened oval regions about 17,000 miles across where material moves about ten percent faster than its surroundings. Although these are the smallest structures yet observed inside the sun, each is still large enough to engulf two Earths, say the solar physicists. The researchers expect to know more from observations of the sun's surface as the star enters its next active cycle, expected to peak around the year 2001. [Cheryl Dybas]
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