Even as the NASDAQ stock market slumped last Monday, the future of high technology never looked so strong.

At a gala black-tie reception in Washing ton, D.C.’s Union Station, the Intel Science Talent Search-which has been adminis- tered for 60 years by Science Service, the publisher of SCIENCE NEws-handed out the top awards in its 2001 competition for high school seniors. Leading the winners were students with projects in physics, math, and computer science.

“You are our long-term planning,” NAS DAQ vice chairman Alfred R. Berkeley I11 told the 40 finalists shortly before the top 10 awards were announced.

The first-place winner, 17-year-old Mariangela Lisanti of Westport, Conn., looked shocked as her name was an- nounced. “1 didn’t expect this at all,” she said.

Lisanti, who won a $100,000 scholar- ship, studied electron transport in gold nanowires using a new measurement technique that collects data more swiftly, cheaply, and easily than do methods cur- rently in wide use by established scien- tists. Lisanti says she also made observa- tions with her apparatus of phenomena never previously reported.

This kind of basic research helps scien- tists understand how objects only a few atoms or molecules across might one day constitute nanoscale electronic de- vices much smaller than any microelec- tronic systems in existence today. The field of nanotechnology is “blossoming right now,” says Lisanti, who hopes her work will have applications for comput- ing, robotics, and biomedicine.

Second place and a $75,000 scholarship went to Nathaniel Jay Craig, 18, of Sacra- mento, Calif., for his mathematical re- search into the properties of supercooled polymeric liquids, which remain fluid even below their freezing points. Studies of such liquids could apply to nuclear- waste storage, biology, and electronics, says Craig, adding that the project has “also been a lot of fun theoretically.”

Gabriel Drew Carroll, 18, of Oakland, Calif., took home the third prize and a $50,000 scholarship for a fundamental- math entry in which he studied the geometry related to so-called partially or- dered sets, or posets.

Fourth through sixth places, along with $25,000 scholarships, were awarded, respectively, to: Alan Mark Dunn, 17, of Potomac, Md., for his encryption re- search; Michael Theprathan Hasper, 18, of Tallahassee, Ha., who tested the physi- cal properties of various violin bridges, the part on which strings rest; and Vinod Easwaran Nambudiri, 17, of Rye Brook, N.Y., who examined how teenagers sleep after they have light shown on the back of their knees.

The seventh-through-tenth finishers

Science Talent Search winners shine bright each won a $20,000 scholarship. The re- cipients, in order, are: Johanna Beth Waldman, 17, of Roslyn, N.Y., for her in- vestigation of factors that affect academ- ic dishonesty; Hans Christiansen Lee, 18, of Carmel, Calif., who built and tested a system for improving a car’s handling; Robert Adam Horch, 18, of Weatherford, Texas, who used a new method to make precisely oriented arrays of molecules; and David Neiad Khalil. 18. of Great Neck.

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N.Y., who used functional magnetic reso- nance imaging to identify areas of the brain associated with perceiving am- biguous images.

Each of the 30 other finalists won a $5,000 scholarship and a computer.

Before the awards banquet, Vice Presi- dent Richard Cheney addressed the final- ists. “Doing well in this competition is a

MARCH 17,2001

Mariangela Lisanti, winner OF the 2001 Science Talent Search, presents her physics research at the National Academy oFSciences in Washington, D.C.

strong indicator of future achievement,” he said, “The sun is just now rising over your professional lives.”

-J. Gorman

Satellites verify greenhouse-gas effects Comparisons of data obtained from

satellites that orbited Earth more than 25 years apart provide rare, direct evidence that the planet’s greenhouse effect in- creased significantly during the closing decades of the 20th century. These new findings support abundant indirect indi- cations that greenhouse gases, such as carbon dioxide and methane, are warm- ing Earth’s atmosphere.

Spectrometers showed that more of the infrared radiation emitted by Earth and leaving the atmosphere was blocked by heat-absorbing greenhouse gases in 1997 than in 1970. This indicates that the plan- et’s natural cooling mechanism has lost some of its effect, says Helen E. Brindley, an atmospheric physicist at Imperial Col- lege in London. She and her colleagues re- port their findings in the March 15 NATURE.

The British researchers used two sets of satellite data: One was collected in 1970 by instruments flown on NASA’s Nimbus 4, and the other was obtained in 1997 from Japan’s Advanced Earth Ob- serving Satellite (ADEOS).

To make valid comparisons between the two data sets, the researchers includ- ed only observations that had been col- lected over the same area of the central Pacific Ocean on cloudless days between April and June of the two years. The re- searchers also intentionally blurred the ADEOS data to match the resolution of the Nimbus 4 numbers.

“This is the first time that satellite measurements have been available to make this type of comparison,” com- ments Barbara E. Carlson, a physical sci- entist at NASA’s Goddard Institute for Space Studies in New York City.

The team’s analysis indicates that most of the increased heat-trapping effects of the atmosphere seen in 1997 occurred at wavelengths of radiation that correspond

SCIENCE NEWS, VOL. 159

to absorption by carbon dioxide, methane, and other greenhouse gases, such as ozone and the chlorofluorocarbons CFC-11 and CFC-12, says Brindley.

The satellite-measured decreases in ra- diation transmitted into space match those predicted in atmospheric models that incorporate known changes since 1970, are both in Earth’s temperature and in the atmospheric concentrations of greenhouse gases, she adds.

The sea-surface temperatures in the tropical Pacific were higher than normal in 1997, which is the hallmark of the El Niiio phenomenon. These higher temper- atures boosted the amount of infrared ra- diation emitted by Earth, Brindley notes. But an increase in greenhouse gases since 1970 intercepted a larger share of that ra- diation, trapping it in the atmosphere. Analyses of data collected over larger por- tions of the globe were consistent with findings from the tropical Pacific.

Normal seasonal variations in atmo- spheric concentrations of greenhouse gases, such as natural summertime in- creases in stratospheric ozone, are too small to account for many of the differ- ences between the two sets of satellite data, Brindley notes.

Neither of the instruments that col- lected the spectra used in her analysis was specifically designed to monitor cli- mate, says Richard M. Goody, an atmo- spheric physicist at Harvard University.

Despite the poor resolution of the Nimbus 4 spectrometer, compared with the modern one that flew on ADEOS, the researchers were able to extract a lot of information about atmospheric changes from the two satellites’ data, Goody notes. “This shows there’s a great future in flying simple, well-calibrated spec- trometers to monitor climate,” he adds.

-S. Perkins

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