New Research Could Lead to Better Climate Models
fifty scientists from more than 40 universities in nine countries are
starting a coordinated program aimed at gaining new insights about the
Earth's climate and the complex, interconnected system involving the
oceans, the atmosphere and the land.
The program, announced on Dec. 7, will study the southeastern
Pacific Ocean, the marine area off South America's west coast -- a
region where the interplay among low clouds, strong low-level winds,
coastal ocean currents, surfacing of deep water, the Andes Mountains,
aerosols and other factors shape the regional climate and affect global
weather in ways that are poorly understood.
"Our research should produce a better understanding of the southeast
Pacific Ocean system and improve our global computer climate models,
which would lead to more confidence in climate forecasts, including
predictions about global warming," said University of California - Los
Angeles (UCLA) professor of atmospheric and oceanic sciences C. Roberto
Mechoso, who chairs the program, known as VOCALS (VAMOS
Ocean-Cloud-Atmosphere-Land Study). "Models currently used for climate
change studies have systematic errors concerning the southeastern
Pacific Ocean, and because the models are not accurate for such an
extensive area, the El Niños they produce in the Pacific are
questionable as well. We hope our research will get rid of, or at least
greatly decrease, these uncertainties."
Variations in the southeast Pacific climate affect rainfall and
temperature worldwide, directly or indirectly, Mechoso believes, but
how the system works is not well understood and therefore cannot be
modeled or predicted accurately.
"Despite its great importance to the Earth's climate system, the
ocean-cloud-atmosphere-land system in the southeast Pacific has been
sparsely observed," Mechoso said. "With VOCALS, that will change
Will VOCALS increase understanding of how much global warming will
occur, and over what period of time? "Absolutely," said Mechoso, an
expert on El Niño who studies the coasts of Ecuador, Peru and Chile.
"We may also produce a better understanding of the dynamics of El Niño.
The relation between the eastern Pacific and El Niño is strong. El Niño
develops in the eastern Pacific, so when the eastern Pacific is not
well represented in climate models, El Niño is not well represented in
the models either."
VOCALS has a scientific modeling program, headed by Mechoso, which
seeks to improve model simulations of key climate processes, and an
experimental field component, headed by Robert Wood, assistant
professor of atmospheric sciences at the University of Washington. This
intensive experimental field program will measure -- using four
aircraft and two research ships containing scientific instruments --
how thick and deep the clouds are, where and why they open, and a
variety of other elements to answer key scientific questions related to
the climate system of the southeast Pacific region. One ship is from
the United States, the other is from Peru; the scientists expect
another ship from either Chile or Ecuador.
"There is tremendous analysis and modeling work that will go along with the field project," Mechoso said.
VOCALS is supported primarily by federal funding from the National
Science Foundation and the National Atmospheric and Oceanic
Administrations. Additional support comes from the U.S. Department of
Energy and the Office of Naval Research, as well as Chile, Peru and the
U.K. Meteorological Office, which provided a research aircraft.
VOCALS, which has a budget of more than $16 million, will continue
for three to five years, beginning in January 2008. The field program
will begin in October 2008 off the coasts of Chile and Peru.
"I believe we have the right questions and the right hypotheses to
guide our work," Mechoso said. "We will learn how the southeastern
Pacific Ocean system works and find out ways to improve the performance
of our climate models."
Mechoso's own research project within VOCALS, in collaboration with
the National Center for Environmental Prediction, aims to improve the
model that is used by the United States for seasonal climate
prediction. The "V" in VOCALS represents an acronym: VAMOS, or
Variability of the American Monsoon Systems. Mechoso was the first
chair of this panel of the World Climate Research Program, which
identified the eastern Pacific as an area where improvement in climate
models is essential.
The scientists in VOCALS are also trying to learn more about the role of aerosol in cloud behavior and climate.
"The role of aerosol in climate is very complex and we are working
very hard to capture aerosol effects in climate models," Mechoso said.
C. Roberto Mechoso: http://www.atmos.ucla.edu/~mechoso