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@comment{{This file has been generated by bib2bib 1.95}}
@comment{{Command line: /usr/bin/bib2bib --quiet -c 'not journal:"Discussions"' -c 'not journal:"Polymer Science"' -c '  author:"Hourdin"  ' -c year=1996 -c $type="ARTICLE" -oc lmd_Hourdin1996.txt -ob lmd_Hourdin1996.bib /home/WWW/LMD/public/}}
  author = {{Collins}, M. and {Lewis}, S.~R. and {Read}, P.~L. and {Hourdin}, F.
  title = {{Baroclinic Wave Transitions in the Martian Atmosphere}},
  journal = {\icarus},
  year = 1996,
  month = apr,
  volume = 120,
  pages = {344-357},
  abstract = {{Surface pressure data from the Viking Lander mission and from GCM
simulations of the martian atmosphere have been analyzed using singular
systems analysis. Very regular oscillations are found with frequencies
that are distributed bimodally with peaks corresponding to periods of
approximately 2-4 days and 5-7 days, respectively. Reconstructions of
the amplitudes of the two oscillations are often negatively correlated;
i.e., when the amplitude of one oscillation is large, that of the other
is small. The GCM simulations show that the negative correlation in the
amplitudes of the two oscillations can be explained as a flipping
between two different wavenumber modes. In the absence of diurnal
forcing in the model, transition from an unrealistically regular high
frequency mode to a similarly unrealistic regular low frequency mode
occurs at most once during the northern winter season. The diurnal cycle
in the model, however, acts in a non-linear sense to stimulate the
transitions between the two wavenumbers and thus increases the frequency
of mode flipping events. The corresponding simulations bear a closer
resemblance to the observations.
  doi = {10.1006/icar.1996.0055},
  adsurl = {},
  adsnote = {Provided by the SAO/NASA Astrophysics Data System}
  author = {{Hutzell}, W.~T. and {McKay}, C.~P. and {Toon}, O.~B. and {Hourdin}, F.
  title = {{Simulations of Titan's Brightness by a Two-Dimensional Haze Model}},
  journal = {\icarus},
  year = 1996,
  month = jan,
  volume = 119,
  pages = {112-129},
  abstract = {{We have used a 2-D microphysics model to study the effects of
atmospheric motions on the albedo of Titan's thick haze layer. We
compare our results to the observed variations of Titan's brightness
with season and latitude. We use two wind fields; the first is a simple
pole-to-pole Hadley cell that reverses twice a year. The second is based
on the results of a preliminary Titan GCM. Seasonally varying wind
fields, with horizontal velocities of about 1 cm sec$^{-1}$at
optical depth unity, are capable of producing the observed change in
geometric albedo of about 10\% over the Titan year. Neither of the two
wind fields can adequately reproduce the latitudinal distribution of
reflectivity seen byVoyager. At visible wavelengths, where only haze
opacity is important, upwelling produces darkening by increasing the
particle size at optical depth unity. This is due to the suspension of
larger particles as well as the lateral removal of smaller particles
from the top of the atmosphere. At UV wavelengths and at 0.89 {$\mu$}m the
albedo is determined by the competing effects of the gas and the haze
material. Gas is bright in the UV and dark at 0.89 {$\mu$}m. Haze transport
at high altitudes controls the UV albedo and transport at low altitude
controls the 0.89-{$\mu$}m albedo. Comparisons between the hemispheric
contrast at UV, visible, and IR wavelengths can be diagnostic of the
vertical structure of the wind field on Titan.
  doi = {10.1006/icar.1996.0005},
  adsurl = {},
  adsnote = {Provided by the SAO/NASA Astrophysics Data System}
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