Unmanned aircraft to study Southern California smog and its consequences

An unmanned aircraft used in the CAPPS program passes the fact of a crescent moon while in flight. The The Scripps-led California AUAV Air Pollution Profiling Study (CAPPS) used unmanned... Click here for more information.

“These monthly UAV flights will provide unprecedented data for evaluating how long range transport of pollutants including ozone, soot and other particulates from the northwest United States, Canada, east Asia and Mexico mix with local pollution and influence our air quality and regional climate including the early melting of snow packs,” said Ramanathan.

Data collection began on April 2, 2008 and will continue through January 2009, offering researchers a chance to view seasonal variations in air pollution.

Ramanathan’s team revolutionized the gathering of atmospheric data in 2006 when the researchers first successfully deployed the aircraft in the Maldives AUAV Campaign (MAC). Miniaturized instruments on the aircraft, which typically flew in formations of three, measured a range of properties such as the quantity and size of the aerosols on which cloud droplets form. The instruments also recorded variables such as temperature, humidity and the intensity of light that permeates clouds and masses of smog. It was the first time such comprehensive measurements were made at a cost that was very low relative to traditional manned flights.

The Scripps researchers have used data from MAC and other field campaigns to observe that a pervasive mass of air pollution in south and east Asia, commonly referred to as the “atmospheric brown cloud,” can disrupt rainfall patterns and cause cooling at ground level but warming at higher altitudes. The cloud typically contains a mix of dust, sulfates and soot and other forms of black carbon. These aerosols are primarily the products of diesel combustion, agricultural biomass burning, use of wood- and cow dung-burning stoves in rural homes and the use of coal in home heating.