NASA THROWS DICE FOR BETTER UNDERSTANDING OF ATMOSPHERE
Care to sample the sea salt, dust and other contaminants over
California until mid-June?
These aerosols fill the air and provide an ideal environment for
a new NASA field experiment starting May 28. As wind blows along
the California coast, across dry deserts, and through urban areas,
NASA scientists and their university partners will test the
accuracy of instruments that measure aerosols -- particles in the
atmosphere -- using NASA's DC-8 aircraft and ground stations.
NASA's Langley Research Center, Hampton, Va., is leading the
DC-8 Inlet/Instrument Characterization Experiment -- or DICE --
based at NASA's Dryden Flight Research Center, Edwards, Calif.
"We plan to fly up the up the central valley of California and
sample pollution. We'll also fly offshore of San Francisco and Los
Angeles to sample sea salt and dust," said Bruce Anderson, the
atmospheric scientist from Langley that is leading the experiment.
"For DICE, we needed a range of aerosol types, and they are
available along the West Coast."
Everyday natural and industrial processes produce aerosols,
including pollution in the lower atmosphere, that significantly
alter the global climate. Depending on their size, chemical
composition and altitude, aerosols either warm the Earth by
absorbing energy or cool the planet by reflecting sunlight. Knowing
how they affect the amount of energy in the Earth's system is one
of the largest uncertainties in determining how climate will change
in the future.
Scientists from Langley, the University of Hawaii, the
University of New Hampshire and the Georgia Institute of Technology
are contributing instruments to the DC-8 payload for the DICE
campaign. They will compare aircraft instrument measurements among
each other and to observations from aerosol-monitoring ground
stations located in California, including ones at Dryden, Rogers
Dry Lake and Trinidad Head.
DICE will enable the scientists to better understand data from
past field experiments and prepare for activities in NASA's
Intercontinental Chemical Transport Experiment-North America or
INTEX-NA. Scheduled for summer 2004, INTEX-NA will study the
exchange of chemicals and aerosols between the land and lower
atmosphere over the U.S. East Coast.
"For INTEX-NA, scientists will look at the quantity of pollution
over North America and how that pollution is transported across the
Atlantic Ocean to Europe," Anderson said.
INTEX-NA will be the latest in a series of NASA field campaigns
to better understand the worldwide chemistry of the troposphere or
the lower atmosphere. Over the past twenty years, NASA has
conducted missions in the Amazon, the Arctic, the tropical Atlantic
and the Pacific to study both natural and human-made processes that
determine the troposphere's chemical makeup.
The second phase of INTEX-NA is scheduled for spring 2006. This
international research effort is part of NASA's Earth Science
Enterprise, dedicated to understanding and protecting our home