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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=2008 -c $type="ARTICLE" -oc lmd_Hourdin2008.txt -ob lmd_Hourdin2008.bib /home/WWW/LMD/public/}}
  author = {{Rio}, C. and {Hourdin}, F.},
  title = {{A Thermal Plume Model for the Convective Boundary Layer: Representation of Cumulus Clouds}},
  journal = {Journal of Atmospheric Sciences},
  year = 2008,
  month = feb,
  volume = 65,
  pages = {407-425},
  doi = {10.1175/2007JAS2256.1},
  adsurl = {},
  adsnote = {Provided by the SAO/NASA Astrophysics Data System}
  author = {{Crespin}, A. and {Lebonnois}, S. and {Vinatier}, S. and {Bézard}, B. and 
	{Coustenis}, A. and {Teanby}, N.~A. and {Achterberg}, R.~K. and 
	{Rannou}, P. and {Hourdin}, F.},
  title = {{Diagnostics of Titan's stratospheric dynamics using Cassini/CIRS data and the 2-dimensional IPSL circulation model}},
  journal = {\icarus},
  year = 2008,
  month = oct,
  volume = 197,
  pages = {556-571},
  abstract = {{The dynamics of Titan's stratosphere is discussed in this study, based
on a comparison between observations by the CIRS instrument on board the
Cassini spacecraft, and results of the 2-dimensional circulation model
developed at the Institute Pierre-Simon Laplace, available at [Rannou, P., Lebonnois, S.,
Hourdin, F., Luz, D., 2005. Adv. Space Res. 36, 2194-2198]. The
comparison aims at both evaluating the model's capabilities and
interpreting the observations concerning: (1) dynamical and thermal
structure using temperature retrievals from Cassini/CIRS and the
vertical profile of zonal wind at the Huygens landing site obtained by
Huygens/DWE; and (2) vertical and latitudinal profiles of stratospheric
gases deduced from Cassini/CIRS data. The modeled thermal structure is
similar to that inferred from observations (Cassini/CIRS and Earth-based
observations). However, the upper stratosphere (above 0.05 mbar) is
systematically too hot in the 2D-CM, and therefore the stratopause
region is not well represented. This bias may be related to the haze
structure and to misrepresented radiative effects in this region, such
as the cooling effect of hydrogen cyanide (HCN). The 2D-CM produces a
strong atmospheric superrotation, with zonal winds reaching 200 m s
$^{-1}$ at high winter latitudes between 200 and 300 km altitude
(0.1-1 mbar). The modeled zonal winds are in good agreement with
retrieved wind fields from occultation observations, Cassini/CIRS and
Huygens/DWE. Changes to the thermal structure are coupled to changes in
the meridional circulation and polar vortex extension, and therefore
affect chemical distributions, especially in winter polar regions. When
a higher altitude haze production source is used, the resulting modeled
meridional circulation is weaker and the vertical and horizontal mixing
due to the polar vortex is less extended in latitude. There is an
overall good agreement between modeled chemical distributions and
observations in equatorial regions. The difference in observed vertical
gradients of C $_{2}$H $_{2}$ and HCN may be an indicator of
the relative strength of circulation and chemical loss of HCN. The
negative vertical gradient of ethylene in the low stratosphere at
15{\deg} S, cannot be modeled with simple 1-dimensional models, where a
strong photochemical sink in the middle stratosphere would be necessary.
It is explained here by dynamical advection from the winter pole towards
the equator in the low stratosphere and by the fact that ethylene does
not condense. Near the winter pole (80{\deg} N), some compounds (C
$_{4}$H $_{2}$, C $_{3}$H $_{4}$) exhibit an
(interior) minimum in the observed abundance vertical profiles, whereas
2D-CM profiles are well mixed all along the atmospheric column. This
minimum can be a diagnostic of the strength of the meridional
circulation, and of the spatial extension of the winter polar vortex
where strong descending motions are present. In the summer hemisphere,
observed stratospheric abundances are uniform in latitude, whereas the
model maintains a residual enrichment over the summer pole from the
spring cell due to a secondary meridional overturning between 1 and 50
mbar, at latitudes south of 40-50{\deg} S. The strength, as well as
spatial and temporal extensions of this structure are a difficulty, that
may be linked to possible misrepresentation of horizontally mixing
processes, due to the restricted 2-dimensional nature of the model. This
restriction should also be kept in mind as a possible source of other
  doi = {10.1016/j.icarus.2008.05.010},
  adsurl = {},
  adsnote = {Provided by the SAO/NASA Astrophysics Data System}
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