New research may lead to better climate models for global warming, El Nino

Environmental News Network: One hundred 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 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 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 drastically."

Will VOCALS increase our 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."…

…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.

Particles in the atmosphere can directly influence radiation from the sun but can also have indirect influences on solar radiation by affecting cloud formation. The United Nations' Intergovernmental Panel on Climate Change (which shared the 2007 Nobel Peace Prize with former Vice President Al Gore) has emphasized the need to reduce the overall uncertainty in the calculation of climate-forcing by aerosol.