Yang Liu

Ph.D., 2004, Harvard Graduate School of Arts and Sciences

M.S., 1999, University of California at Davis

B.S., 1997, Tsinghua University, China

Fine particulate matters (PM2.5) are a complex mixture of tiny airborne particles and droplets.  There has been increasing evidence that exposure to PM2.5 is associated with significant adverse health effects.  Until very recently, ground air quality monitoring networks have been the only data source for estimating population exposure to PM2.5.  However, even in the US, the spatial coverage of these networks are quite limited due to high operating cost.  In the rest of the world, routine PM2.5 monitoring almost does not exist.

The rapid development of satellite aerosol remote sensing technology provides a new possibility - monitoring air pollution globally from space.  Compared with ground monitoring stations, earth observing satellites have the natural advantage of broad spatial coverage.  My research focuses on the application of satellite remote sensing in PM2.5 exposure and epidemiology studies.  I have worked on (1) validating MISR satellite data with ground truth; (2) using satellite retrieved Aerosol Optical Depth (AOD) / meteorology / Chemical Transport Model (CTM) results to estimate PM2.5 concentrations; and (3) deriving PM2.5 chemical speciation and size distributions with satellite retrieved particle size and shape information.

My work now focuses on (1) developing spatial statistical models to predict a 2-D PM2.5 concentration surface using satellite data together with assimilated meteorology  and GIS information; and (2) applying the above model in particle health effect studies.

News Links

On May 31, 2007, my research on comparing two NASA sensors in their capabilities to predict PM2.5 concentrations was featured on Jet Propulsion Laboratory (JPL) website.

This research is also featured on NASA Langley Atmospheric Science Data Center website.

On September 15, 2007, my research was featured on Earth & Sky, a radio program of National Public Radio (NPR). You can also download a MP3 file of their radio show.