Residents in California's San Joaquin Valley will see some unusual air traffic over their region that is designed to some day help improve the air all of us breathe. Two NASA research planes will fly between Bakersfield and Fresno - one as close as 1,000 feet to the ground – to measure air pollution with a number of onboard science instruments.

The planes are part of a five-year, $30 million NASA science study called DISCOVER-AQ, which stands for Deriving Information on Surface conditions from Column and Vertically Resolved Observations Relevant to Air Quality. Its team of researchers is working to improve the ability of satellites to consistently observe air quality in the lowest part of the atmosphere. If scientists could more effectively observe pollution from space, they would be able to make better air quality forecasts and more accurately determine where pollution is coming from and how emissions vary. That understanding could also help researchers develop successful strategies to reduce pollution.

One of the big challenges for instruments monitoring air quality from space is to distinguish between pollution high in the atmosphere and pollution near the surface where people live. DISCOVER-AQ will make measurements from the aircraft and from ground-based monitoring sites to help scientists better understand how to "see" ground-level pollution from space in the future.

Flights are scheduled to start January 16 and go through mid-February. A four-engine P-3B turboprop plane from the Wallops Flight Facility in Wallops Island, Va., will carry eight science instruments. A two-engine B200 King Air aircraft from NASA Langley will carry two remote sensors. Sampling will focus on agricultural and vehicle traffic areas extending from Bakersfield to Fresno.

To capture data on the valley's air quality the117-foot-long P-3B will fly low-altitude spiral profiles over the ground stations. These profiles will extend from as high as 15,000 feet down to 1,000 feet from the ground. The flights will sample air along agricultural and traffic corridors at low altitude between ground stations.

The smaller B200 King Air will collect data from as high as 26,000 feet. The plane's instruments will look down at the surface, much like a satellite instrument, and measure particulate and gaseous air pollution.