Unmanned aircraft to study Southern California smog and its consequences

Ramanathan and his team linked the brown cloud to an observed acceleration of glacial melt in the Himalayas. Himalayan glaciers provide billions of people in Asia with their drinking water.

In CAPPS, the Scripps team hopes to determine how much of Southern California’s air pollution comes from Asia, Mexico and from regions north of California. Scientists routinely observe aerosol masses traveling across the Pacific Ocean to the West Coast but are still trying to understand the effects of that pollution. The imported smog is only one of several sources of atmospheric aerosols in Southern California, joining local auto and industrial emissions and smoke from wildfires. Researchers have seen evidence that this air pollution can mix with falling snow and accelerate its melt when sunlight hits and warms the “dirty” snow in mountain watersheds.

“Black carbon and ozone are two major contributors to global warming, next to carbon dioxide,” said Ramanathan. “We hope to document the vertical profiles of black carbon and ozone and their climate warming effects for the first time over California, and this data will likely help California reduce its global warming commitment.”

The California Energy Commission’s Public Interest Energy Research (PIER) program will employ CAPPS results in an analysis of the potential future economic and ecological consequences of Southern California air pollution. Scientists also hope to combine CAPPS results with satellite data to better understand the role of aerosols at a larger regional scale.

“As we learn more about the air we breathe and seek solutions to reduce greenhouse gases, this important atmospheric research will help us address the serious challenges to California’s water resources, ecology, and the health of our residents,” said Energy Commissioner Arthur Rosenfeld. “With this study, California continues to demonstrate its commitment as a national leader in climate change research.”

The aircraft will profile atmospheric conditions at altitudes ranging between 2,000 and 12,000 feet. Because of Federal Aviation Administration regulations that prohibit unmanned aircraft from flying in public airspace, the flight paths will be limited to military airspace, which is exempted from FAA rules. The researchers hope to conduct the flights at least once a month or as often as every two weeks. The Scripps team also hopes to gather data on a situational basis such as during wildfires.