ARM Mobile Facility Moves to China in 2008 for Study of Aerosol Impacts on Climate

 
Published: 11 January 2007

Onshore winds and a mountain range to the west of Shanghai form a natural basin which traps particulates in the air above the Yangtze River delta region.  (Illustration courtesy of Patricia Ebrey, University of Washington)

China generates exceptionally high amounts of aerosol particles whose influence on the atmosphere has been detected across the Pacific Rim. In the Yangtze River delta in southeast China, these high aerosol loadings result from both natural and manmade sources. With a subtropical climate characterized by marine monsoons, atmospheric conditions in this region change quickly but in a cyclic nature. Thus, the area is a good location to collect continuous data that will help scientists identify and quantify the climate effects of aerosols. Unfortunately, China is one of the least observed regions in the world, especially in terms of aerosol and cloud properties.

In 2008, the ARM Mobile Facility (AMF) will be deployed near Shanghai—the largest industrial city in China—to acquire essential cloud, aerosol, radiative, and meteorological measurements. An ancillary site will be established near Beijing, north of Shanghai, to obtain comparative measurements. The two sites are located in regions with different climate regimes—Shanghai being generally warm and humid, and Beijing experiencing hot, humid summers and cold, dry winters—and with high aerosol loadings of different optical, physical, chemical properties.

Preliminary analyses of multiple satellite datasets indicate more complex and unique aerosol indirect effects—such as cloud reflectivity and precipitation processes—in China than are found in relatively cleaner environments. Both in-situ measurements and independent ground-based remote sensing data are needed to verify the satellite findings and gain a deeper understanding of these effects. Measurements obtained by the AMF in China during the 1-year Aerosol Indirect Effects Study will help scientists to validate satellite-based findings, understand the mechanisms of the aerosol indirect effects in the region, and examine the roles of aerosols in affecting regional climate and atmospheric circulation, with a special focus on the impact of the East Asian monsoon system.