July 22, 1999
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:
Natural gas hydrates -- a mixture of methane and water frozen into a
solid crystalline state -- were first discovered in marine sediments in
the 1970s. However, it is only recently that the pace of research into
their nature has significantly increased, according to Bilal Haq, director
of the National Science Foundation’s (NSF) marine geology and geophysics
program, and author of an article in the July 23rd issue of Science.
Recent estimates indicate that on the order of 10,000 gigatons of carbon,
or double the amount of all known fossil fuel sources, may be stored in
gas hydrates. Thus far, Haq believes, the petroleum industry has been
less interested in gas hydrates as a resource because they may not be
easy to recover or costeffective to exploit. (Most gas hydrate is thinly
dispersed in the pore spaces of sediments on the sea floor, at water depths
greater than 1,500 feet.) Only rarely, he writes in Science, do gas hydrates
occur in locally concentrated areas, such as on the Blake Ridge off the
East Coast of the United States. Gas hydrates have also been implicated
in massive slumps and slides on the continental slope; when hydrates break
down, they cause local earthquakes and pose hazards to petroleum drilling
rigs and undersea cables.
Substantial uncertainty remains about how gas hydrates are formed and
about the nature and location of their reservoirs, as well as what their
energy and climate change potential may be. To address these issues, Haq
suggests, we need to better understand the physical, chemical and biological
processes within hydrate sediments, and the fate of methane in ocean water
once it is released from the seafloor as hydrates break down. [Cheryl
Dybas]
Top of Page
Large quantities of dust, originating in Africa, are blown across the
Atlantic Ocean each summer and constitute up to one half of breathable
particles in the air over Miami, Florida, according to a new study funded
in part by the NSF. African dust can on certain days push the total number
of airborne particles above the limit set by the Clean Air Act.
The study, by Joseph Prospero of the University of Miami's Rosenstiel
School of Marine and Atmospheric Sciences, appeared in the July 20 issue
of the Journal of Geophysical Research, published by the American
Geophysical Union. Describing himself as a "champion of dust," Prospero
reviewed 23 years of measurements of airborne particles, or aerosols,
at a coastal site in Miami. He believes the impact of African dust is
comparable throughout the southeastern United States.
Prospero emphasizes
that there is nothing new about the transoceanic transport of African
dust. He says it has been occurring on a geologic time scale, giving the
example that soil composition in Bermuda is consistent with African dust
sources and shows little evidence of North American inputs. [Cheryl Dybas]
Top of Page
Highlighting the need to "find, educate, train, develop and keep high
quality teachers for K-12 math and science education," NSF director Rita
R. Colwell has accepted an appointment to a 26 member National Commission
on Mathematics and Science Education for the 21st Century.
The commission, formed by Secretary of Education Richard W. Riley and
chaired by former U.S. Senator and astronaut John Glenn, seeks to develop
a strategy to improve the quality of science and mathematics education
nationwide by addressing several issues over the next year. Among them
are how to deal with major shortages of teachers created by large numbers
of expected retirements (especially in math and science), the lack of
adequate credentials among math and science teachers and a booming student
population.
"The paradox we face is multi-faceted," Colwell said. "We lead the world
in innovation and discovery but we trail our international counterparts
in K-12 math and science education."
Colwell said that the commission
has a unique opportunity, 30 years after America's first moon landing,
to "develop a cadre of motivated teachers who will carry their commitment
into the next century." [Bill Noxon]
For the full statement, see: http://www.nsf.gov/od/lpa/news/media/statemts.htm Top of Page
|