ATMOSPHERIC PROFILING CENTER FOR DISCOVERY
Air quality is the
result of complex interactions between meteorology
(wind and rain), natural and anthropogenic (man-made)
emissions of precursor gases, and atmospheric photochemistry.
This chemical soup has important implications for
air and water pollution, rainfall, climate, and other
processes that regulate ecosystem activity.
To understand these complex processes, we are developing
measurement and modeling tools to study atmospheric
trace constituents to determine the accuracy of our
air-quality regulatory models. The heart of the measurement
complex resides in the laboratories of the Regional
Atmospheric Profiling Center for Discovery, RAPCD
(pronounced rhapsody). This center, located in Huntsville,
Alabama, is part of the National Space Science and
Technology Center (NSSTC) and comprises investigators
universities, three NASA centers, and two NOAA laboratories.
The RAPCD infrastructure includes 1400
square feet of laboratory space on the top floor
of the NSSTC annex with six vibration-isolated optical
remote-sensing chimneys through the roof, and 1900
square feet of platform space on the roof . Remote-sensing
instrumentation includes four pulsed lidars and a
Fourier transform infrared (FTIR) spectrometer, for measuring
vertical profiles of ozone, winds, aerosols, and
other trace gases.
An additional FTIR obtains fundamental measurements
on simulated atmospheric constituents in laboratory
chambers. Two CG4 Pyrgeometers have recently
been added to the RAPCD instrumentation facilities. These
instruments collect data that is analyzed and used
for inputs into radiative transfer models. A new
FTIR in RAPCD will be used as a cryogenic air quality
monitoring system sampling for speciated VOC’s. By
using state-of-the-science technology, we will continuously
measure the three-dimensional structure of atmospheric
ozone, aerosols, and wind fields.
Currently, only four locations in the United States
(Trinidad Head, CA; Boulder, CO; Huntsville, AL;
and Wallops Island, VA) make regular (and then only
weekly) measurements of the ozone vertical profile
with balloon-borne ozonesondes and
one site (Table Mountain Facility, CA) makes regular
ozone lidar measurement. Other gases and aerosols
are not regularly profiles anywhere in the US. Along
with the few other profiling sites in the US we would
like to form a regional network to measure and model
the three-dimensional structure of air pollution.
We are also forming a computer-modeling center for
calculating the atmospheric state with the latest
EPA air-quality model (CMAQ) driven by the Penn State
University/NCAR meteorological model, MM5, coupled
with EPA’s Models3/CMAQ (Community Multiscale
Air Quality model) for 3D chemical transport modeling.
We will assess the accuracy of these model calculations
and the processes that occur to produce a variety
of air quality conditions by using satellite observation
of trace gases and aerosols. We will be addressing
the urban/regional air pollution issues with a view
of its larger impact on global tropospheric chemistry.
Drawing on our current assets in satellite remote
sensing of chemical constituents, meteorological
modeling, and laboratory measurements implemented
in a structure of higher education for undergraduate
and graduate students, we will produce a national
asset of the highest caliber for measuring and assessing
the causes and cures for regional air pollution.