Researchers from Texas, California and Washington recently compared air pollution data provided by the Intergovernmental Panel on Climate Change for the years 1850 through 2000 and found that human-made atmospheric particulates (aerosols) from Asia are having an impact on the Pacific storm track, which is a critical driver of global atmospheric circulation that influences weather over most of the world.
The researchers took this historical data and fed it into an advanced global climate model (GCM), a computer model of the general circulation of Earth’s atmosphere, to produce two climate scenarios. One of these scenarios reflected conditions of 1850, considered to be a time period before the industrial era. The other represented the conditions of 2000, or present time.
Writing in a recent edition of the Proceedings of the National Academy of Sciences (PNAS), the researchers from Texas A&M University, the Pacific Northwest National Laboratory in Richland Washington, the University of California at San Diego and NASA’s Jet Propulsion Laboratory compared the results of the two scenarios and found that human-made aerosols (particulates) overwhelmingly impact cloud formations and mid-latitude cyclones, also called extra tropical cyclones, that are usually associated with the Pacific storm track.
The Pacific storm track transports heat and moisture along its path and the researchers said that they have found an increase in the transfer of heat and moisture that appears further along the storm track, which they said means that the Pacific storm track is intensified because of the discharge of Asian air pollution.
Recent research has shown that atmospheric aerosols affect the world’s climate by dispersing or absorbing the sun’s radiation and by changing the formation of clouds.
Scientists have expressed concern about the rising levels of these particulates in the atmosphere because of the possible effects they could have on regional to worldwide atmospheric circulation.
“There appears to be little doubt that these particles from Asia affect storms sweeping across the Pacific and subsequently the weather patterns in North America and the rest of the world,” said Renyi Zhang from Texas A&M’s Department of Atmospheric Sciences, one of the study’s authors.
Zhang said that the results in the two scenarios produced by the climate model used by his team clearly indicate that aerosols made by human activities from “fast-growing Asian economies” not only impact the formation of storms but also global air circulation along the Pacific storm track.
The researchers also found that the increased pollution from Asia tends to make storms over the Pacific deeper, stronger and more intense, producing more precipitation.
“Our results support previous findings that show that particles in the air over Asia tend to affect global weather patterns,” Zhang said. “It shows they can affect the Earth’s weather significantly.”