Wednesday, 14 January 2009: 9:30 AM
End-to-end testbed for rapid analysis of laser remote sensing data and application to flight data in preparation for ASCENDS
Room 122A (Phoenix Convention Center)
T. Scott Zaccheo, AER, Inc., Lexington, MA; and H. E. Snell, J. Dobler, M. E. Dobbs, E. V. Browell, and B. Moore
Poster PDF
(108.6 kB)
This
work describes the design and use of an extensible testbed developed
to provide end-to-end simulation and analysis of laser-based remote
sensing systems. This testbed provides a graphical user interface
(GUI) based set of tools for simulating sensor performance, and a
modular framework that facilitates the comparison of measured data
from prototype/operational instruments with modeled results. This
framework provides standardized interfaces/interface approaches for
combining community line-by-line radiative transfer (RT) models with
atmospheric state information obtained from historical databases and
in situ
measurements. In the examples presented in this work, the
line-by-line radiative transfer model LBLRTM was integrated with
profiles obtained from historical databases and in
situ
measurements. Using a comprehensive RT modeling approach not only
provides information about the primary absorption feature, but also
the impact of other trace gases on the measurements. Our
presentation focuses on the utility of the testbed in the analysis of
aircraft flight data acquired using a fiber laser based instrument
designed and developed by ITT to measure carbon dioxide (CO2)
column amounts. Surface/atmospheric temperature, moisture and
pressure information was obtained from rawin/radiosonde launched in
conjunction with the flight campaigns or as part of
national/international networks. In addition, CO2
profile data were obtained from coincident in
situ
measurements collected by NASA Langley Research Center (LARC). Using
this data we present measured differential optical depths for several
configurations of the instrument and the corresponding model results. We also illustrate how our analysis tools allow for the estimation
of errors due to uncertainties in atmospheric state and an assessment
of a first order correction designed to minimize the differences
between measurements and modeled results due to a complex set of
terms, such as instrument calibration biases and uncertainties in
spectral knowledge.
Supplementary URL:
