W. Wallace McMillan, Barry Baker, and Lynn Sparling, Department of Physics

In late August 2009, fires near Los Angeles created a pyrocumulus cloud
which lofted a large amount of Carbon Monoxide (CO) into the atmosphere.
Tracking the CO emissions using satellite observations from the
Atmospheric InfraRed Sounder (AIRS), one sees that the air follows a
path over downwind cities including Denver and Houston. Ground based
measurements taken from Denver, rural Oklahoma, and Houston coincident
with the observations from AIRS demonstrate that the Los Angeles fires
affected the air quality in these downwind locations. Although AIRS
provides a very large spatial coverage with a 1600 km swath and a 45 km
nadir spatial resolution, it has a limited vertical resolution. To
determine the altitude of CO transport, trajectories are run forward in
time from the fire locations and backward in time from the ground-based
measurements to see which transport altitudes match the satellite CO
observations. The wind model for this project is the UMBC LT model
using the North American Regional Reanalysis (NARR) data as input. NARR
has a 30 km spatial resolution. Validation of AIRS satellite
observations can be accomplished through comparison to downwind ground
based observations taken on the days subsequent to the Los Angeles
fires. Furthermore, validation of the UMBC LT model can be accomplished
by comparing results with both AIRS CO observations and ground based
measurements.