pubmars0.bib
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@comment{{Command line: bib2bib --quiet -c abstract:"Mars" -c $type="ARTICLE" -oc pubmars0.txt -ob pubmars0.bib lebonnois.link.bib}}
@article{2009JGRE..114.1004F,
author = {{Forget}, F. and {Montmessin}, F. and {Bertaux}, J.-L. and {Gonz{\'a}lez-Galindo}, F. and
{Lebonnois}, S. and {Quémerais}, E. and {Reberac}, A. and
{Dimarellis}, E. and {L{\'o}pez-Valverde}, M.~A.},
title = {{Density and temperatures of the upper Martian atmosphere measured by stellar occultations with Mars Express SPICAM}},
journal = {Journal of Geophysical Research (Planets)},
keywords = {Planetary Sciences: Fluid Planets: Atmospheres (0343, 1060), Planetary Sciences: Solar System Objects: Mars, Atmospheric Composition and Structure: Pressure, density, and temperature},
year = 2009,
volume = 114,
eid = {E01004},
pages = {1004},
abstract = {{We present one Martian year of observations of the density and
temperature in the upper atmosphere of Mars (between 60 and 130 km)
obtained by the Mars Express ultraviolet spectrometer Spectroscopy for
Investigation of Characteristics of the Atmosphere of Mars (SPICAM). Six
hundred sixteen profiles were retrieved using stellar occultations
technique at various latitude and longitude. The atmospheric densities
exhibit large seasonal fluctuations due to variations in the dust
content of the lower atmosphere which controls the temperature and,
thus, the atmospheric scale height, below 50 km. In particular, the year
observed by SPICAM was affected by an unexpected dust loading around Ls
= 130{\deg} which induced a sudden increase of density above 60 km. The
diurnal cycle could not be analyzed in detail because most data were
obtained at nighttime, except for a few occultations observed around
noon during northern winter. There, the averaged midday profile is found
to slightly differ from the corresponding midnight profile, with the
observed differences being consistent with propagating thermal tides and
variations in local solar heating. About 6\% of the observed mesopause
temperatures exhibits temperature below the CO$_{2}$ frost point,
especially during northern summer in the tropics. Comparison with
atmospheric general circulation model predictions shows that the
existing models overestimate the temperature around the mesopause (above
80 to 100 km) by up to 30 K, probably because of an underestimation of
the atomic oxygen concentration which controls the CO$_{2}$
infrared cooling.
}},
doi = {10.1029/2008JE003086},
adsurl = {http://cdsads.u-strasbg.fr/abs/2009JGRE..114.1004F},
localpdf = {REF/2009JGRE..114.1004F.pdf},
adsnote = {Provided by the SAO/NASA Astrophysics Data System}
}
@article{2008Natur.454..971L,
author = {{Lefèvre}, F. and {Bertaux}, J.-L. and {Clancy}, R.~T. and
{Encrenaz}, T. and {Fast}, K. and {Forget}, F. and {Lebonnois}, S. and
{Montmessin}, F. and {Perrier}, S.},
title = {{Heterogeneous chemistry in the atmosphere of Mars}},
journal = {\nat},
year = 2008,
volume = 454,
pages = {971-975},
abstract = {{Hydrogen radicals are produced in the martian atmosphere by the
photolysis of water vapour and subsequently initiate catalytic cycles
that recycle carbon dioxide from its photolysis product carbon monoxide.
These processes provide a qualitative explanation for the stability of
the atmosphere of Mars, which contains 95 per cent carbon dioxide.
Balancing carbon dioxide production and loss based on our current
understanding of the gas-phase chemistry in the martian atmosphere has,
however, proven to be difficult. Interactions between gaseous chemical
species and ice cloud particles have been shown to be key factors in the
loss of polar ozone observed in the Earth's stratosphere, and may
significantly perturb the chemistry of the Earth's upper troposphere.
Water-ice clouds are also commonly observed in the atmosphere of Mars
and it has been suggested previously that heterogeneous chemistry could
have an important impact on the composition of the martian atmosphere.
Here we use a state-of-the-art general circulation model together with
new observations of the martian ozone layer to show that model
simulations that include chemical reactions occurring on ice clouds lead
to much improved quantitative agreement with observed martian ozone
levels in comparison with model simulations based on gas-phase chemistry
alone. Ozone is readily destroyed by hydrogen radicals and is therefore
a sensitive tracer of the chemistry that regulates the atmosphere of
Mars. Our results suggest that heterogeneous chemistry on ice clouds
plays an important role in controlling the stability and composition of
the martian atmosphere.
}},
doi = {10.1038/nature07116},
adsurl = {http://cdsads.u-strasbg.fr/abs/2008Natur.454..971L},
localpdf = {REF/2008Natur.454..971L.pdf},
adsnote = {Provided by the SAO/NASA Astrophysics Data System}
}
@article{2008Icar..195..547E,
author = {{Encrenaz}, T. and {Greathouse}, T.~K. and {Richter}, M.~J. and
{Bézard}, B. and {Fouchet}, T. and {Lefèvre}, F. and
{Montmessin}, F. and {Forget}, F. and {Lebonnois}, S. and {Atreya}, S.~K.
},
title = {{Simultaneous mapping of H $_{2}$O and H $_{2}$O $_{2}$ on Mars from infrared high-resolution imaging spectroscopy}},
journal = {\icarus},
year = 2008,
volume = 195,
pages = {547-556},
abstract = {{New maps of martian water vapor and hydrogen peroxide have been obtained
in November-December 2005, using the Texas Echelon Cross Echelle
Spectrograph (TEXES) at the NASA Infra Red Telescope facility (IRTF) at
Mauna Kea Observatory. The solar longitude L was 332{\deg} (end of
southern summer). Data have been obtained at 1235-1243 cm $^{-1}$,
with a spectral resolution of 0.016 cm $^{-1}$ ( R=8{\times}10).
The mean water vapor mixing ratio in the region [0{\deg}-55{\deg} S;
345{\deg}-45{\deg} W], at the evening limb, is 150{\plusmn}50 ppm
(corresponding to a column density of 8.3{\plusmn}2.8 pr-{$\mu$}m). The mean
water vapor abundance derived from our measurements is in global overall
agreement with the TES and Mars Express results, as well as the GCM
models, however its spatial distribution looks different from the GCM
predictions, with evidence for an enhancement at low latitudes toward
the evening side. The inferred mean H $_{2}$O $_{2}$
abundance is 15{\plusmn}10 ppb, which is significantly lower than the
June 2003 result [Encrenaz, T., Bézard, B., Greathouse, T.K.,
Richter, M.J., Lacy, J.H., Atreya, S.K., Wong, A.S., Lebonnois, S.,
Lefèvre, F., Forget, F., 2004. Icarus 170, 424-429] and lower
than expected from the photochemical models, taking in account the
change in season. Its spatial distribution shows some similarities with
the map predicted by the GCM but the discrepancy in the H $_{2}$O
$_{2}$ abundance remains to be understood and modeled.
}},
doi = {10.1016/j.icarus.2008.01.022},
adsurl = {http://cdsads.u-strasbg.fr/abs/2008Icar..195..547E},
localpdf = {REF/2008Icar..195..547E.pdf},
adsnote = {Provided by the SAO/NASA Astrophysics Data System}
}
@article{2006JGRE..11110S90B,
author = {{Bertaux}, J.-L. and {Korablev}, O. and {Perrier}, S. and {Quémerais}, E. and
{Montmessin}, F. and {Leblanc}, F. and {Lebonnois}, S. and {Rannou}, P. and
{Lefèvre}, F. and {Forget}, F. and {Fedorova}, A. and {Dimarellis}, E. and
{Reberac}, A. and {Fonteyn}, D. and {Chaufray}, J.~Y. and {Guibert}, S.
},
title = {{SPICAM on Mars Express: Observing modes and overview of UV spectrometer data and scientific results}},
journal = {Journal of Geophysical Research (Planets)},
keywords = {Planetary Sciences: Solid Surface Planets: Atmospheres (0343, 1060), Planetary Sciences: Solid Surface Planets: Aurorae and airglow, Planetary Sciences: Solid Surface Planets: Composition (1060, 3672), Planetary Sciences: Solid Surface Planets: Instruments and techniques, Planetary Sciences: Solid Surface Planets: General or miscellaneous},
year = 2006,
volume = 111,
number = e10,
eid = {E10S90},
pages = {10},
abstract = {{This paper is intended as an introduction to several companion papers
describing the results obtained by the SPICAM instrument on board Mars
Express orbiter. SPICAM is a lightweight (4.7 kg) UV-IR dual
spectrometer dedicated primarily to the study of the atmosphere of Mars.
The SPICAM IR spectrometer and its results are described in another
companion paper. SPICAM is the first instrument to perform stellar
occultations at Mars, and its UV imaging spectrometer (118-320 nm,
resolution \~{}1.5 nm, intensified CCD detector) was designed primarily to
obtain atmospheric vertical profiles by stellar occultation. The
wavelength range was dictated by the strong UV absorption of
CO$_{2}$ ({$\lambda$} {\lt} 200 nm) and the strong Hartley ozone
absorption (220-280 nm). The UV spectrometer is described in some
detail. The capacity to orient the spacecraft allows a great versatility
of observation modes: nadir and limb viewing (both day and night) and
solar and stellar occultations, which are briefly described. The
absolute calibration is derived from the observation of UV-rich stars.
An overview of a number of scientific results is presented, already
published or found in more detail as companion papers in this special
section. SPICAM UV findings are relevant to CO$_{2}$, ozone, dust,
cloud vertical profiles, the ozone column, dayglow, and nightglow. This
paper is particularly intended to provide the incentive for SPICAM data
exploitation, available to the whole scientific community in the ESA
data archive, and to help the SPICAM data users to better understand the
instrument and the various data collection modes, for an optimized
scientific return.
}},
doi = {10.1029/2006JE002690},
adsurl = {http://cdsads.u-strasbg.fr/abs/2006JGRE..11110S90B},
localpdf = {REF/2006JGRE..11110S90B.pdf},
adsnote = {Provided by the SAO/NASA Astrophysics Data System}
}
@article{2006JGRE..111.9S09M,
author = {{Montmessin}, F. and {Quémerais}, E. and {Bertaux}, J.~L. and
{Korablev}, O. and {Rannou}, P. and {Lebonnois}, S.},
title = {{Stellar occultations at UV wavelengths by the SPICAM instrument: Retrieval and analysis of Martian haze profiles}},
journal = {Journal of Geophysical Research (Planets)},
keywords = {History of Geophysics: Planetology, Planetary Sciences: Solid Surface Planets: Atmospheres (0343, 1060), Planetary Sciences: Solid Surface Planets: Meteorology (3346), Atmospheric Composition and Structure: Aerosols and particles (0345, 4801, 4906), Atmospheric Composition and Structure: Planetary atmospheres (5210, 5405, 5704)},
year = 2006,
volume = 111,
eid = {E09S09},
pages = {9},
abstract = {{Observations made by the SPICAM ultraviolet spectrometer on board the
Mars Express orbiter are presented. We focus on several hundreds of
atmospheric profiles which have been collected over 3/4 of a Martian
year by making use of the stellar occultation technique. The typical
structure of the Martian haze possesses at least one discrete layer (60\%
of all cases) standing over an extended portion wherein opacity
continuously increases down to the surface. Differences of morphology
are, however, noted between profiles observed near the equator and
profiles collected elsewhere. The Martian haze exhibits a pronounced
seasonal signal manifested by variations of the maximum elevation at
which particles are observed. For reasons related to both convective
activity and changes in the hygropause level, cold regions display a
much lower hazetop than warm regions. Using UV spectrometry data, we put
constraints on haze microphysical properties. Vertical variations of
particle size are keyed to variations of opacity; e.g., an increase of
particle size is systematically observed near extinction peaks. This is
the likely consequence of cloud formation which results into a local
increase of particle cross section. Despite marked differences of
aerosol profiles between low and high latitudes, haze properties above
60 km remain invariant, possibly reflecting the long-term presence of a
background submicronic particle population. Several profiles have been
analyzed in more detail to extract properties of detached cloud layers
lofted above 40 km. Their optical depth ranges between 0.01 and 0.1 in
the visible. Estimation of cloud particle size is technically restricted
because of SPICAM wavelength sampling, but it generally yields a minimum
radius value of about 0.3 {$\mu$}m, while several estimates are consistent
with a robust 0.1-0.2 {$\mu$}m. This crystal size, significantly smaller
than the 1 to 4 {$\mu$}m associated with recently classified type I and II
clouds, suggests that a different class of clouds, henceforth type III
clouds, can be extracted from our data. Observations made in the
southern winter polar night indicate a very distinct aerosol behavior
where particles are less abundant ({$\tau$} {\lt} 0.1), confined to lower
heights (vertical profile consistent with a Conrath parameter exceeding
0.04) and made of particles having a radius on the order of 0.1 {$\mu$}m.
This shows that the Martian polar night is a region with a very clean
atmosphere and with a distinct type of aerosols.
}},
doi = {10.1029/2005JE002662},
adsurl = {http://cdsads.u-strasbg.fr/abs/2006JGRE..111.9S09M},
localpdf = {REF/2006JGRE..111.9S09M.pdf},
adsnote = {Provided by the SAO/NASA Astrophysics Data System}
}
@article{2006JGRE..111.9S06P,
author = {{Perrier}, S. and {Bertaux}, J.~L. and {Lefèvre}, F. and
{Lebonnois}, S. and {Korablev}, O. and {Fedorova}, A. and {Montmessin}, F.
},
title = {{Global distribution of total ozone on Mars from SPICAM/MEX UV measurements}},
journal = {Journal of Geophysical Research (Planets)},
keywords = {Atmospheric Composition and Structure: Planetary atmospheres (5210, 5405, 5704), Planetary Sciences: Solar System Objects: Mars, Planetary Sciences: Astrobiology: Planetary atmospheres, clouds, and hazes (0343)},
year = 2006,
volume = 111,
eid = {E09S06},
pages = {9},
abstract = {{The dual UV/IR spectrometer SPICAM on board the European mission Mars
Express is dedicated to monitoring the Martian atmosphere and has
recorded spectra for more than one Martian year, from January 2004 to
April 2006, over a large range of latitudes and longitudes. SPICAM UV
spectra were recorded on the day side in a nadir geometry, in the
110-320 nm range, allowing measurement of ozone absorption around 250
nm. The method used to retrieve column-integrated ozone quantities is
described. A full radiative transfer forward model of the radiance
factor is used in an iterative loop to fit the data with four
parameters: the surface albedo at 210 and 300 nm, the dust opacity, and
the total ozone column. The analysis of the complete data set is
presented. The global climatology of ozone on Mars is retrieved for the
first time with spatial and temporal coverage. The most significant
findings are (1) large increases in the ozone column density at high
latitudes during late winter-early spring of each hemisphere that
totally disappear during summer, (2) a large variability of the northern
spring content related to the polar vortex oscillations, (3) low ozone
columns in the equatorial regions all year long, and (4) local
variations of the ozone column related to topography, mainly above
Hellas Planitia. A good overall agreement is obtained comparing SPICAM
data to predictions of a Chemical General Circulation Model. However,
significant discrepancies in total abundances are found near northern
spring when ozone reaches its annual peak. These results will help
further understanding of the dynamics and chemistry of Mars atmosphere.
}},
doi = {10.1029/2006JE002681},
adsurl = {http://cdsads.u-strasbg.fr/abs/2006JGRE..111.9S06P},
localpdf = {REF/2006JGRE..111.9S06P.pdf},
adsnote = {Provided by the SAO/NASA Astrophysics Data System}
}
@article{2006JGRE..111.9S05L,
author = {{Lebonnois}, S. and {Quémerais}, E. and {Montmessin}, F. and
{Lefèvre}, F. and {Perrier}, S. and {Bertaux}, J.-L. and
{Forget}, F.},
title = {{Vertical distribution of ozone on Mars as measured by SPICAM/Mars Express using stellar occultations}},
journal = {Journal of Geophysical Research (Planets)},
keywords = {Planetary Sciences: Solar System Objects: Mars, Planetary Sciences: Solid Surface Planets: Composition (1060, 3672), Planetary Sciences: Solid Surface Planets: Remote sensing, Atmospheric Composition and Structure: Planetary atmospheres (5210, 5405, 5704)},
year = 2006,
volume = 111,
eid = {E09S05},
pages = {9},
abstract = {{The ultraviolet spectrometer of the SPICAM instrument on board the
European Mars Express mission has performed stellar occultations to
probe the atmosphere. Vertical profiles of ozone are retrieved from
inversion of transmission spectra in the altitude range 20-30 to 70 km.
They are analyzed here as functions of latitude and season of the
observations. These occultations have been monitored on the night side,
from northern spring equinox (L$_{s}$ = 8{\deg}) to northern winter
solstice (L$_{s}$ = 270{\deg}). The profiles show the presence of
two ozone layers: (1) one located near the surface, the top of which is
visible below 30 km altitude, and (2) one layer located in the altitude
range 30 to 60 km, a feature that is highly variable with latitude and
season. This layer is first seen after L$_{s}$ = 11{\deg}, and the
ozone abundance at the peak tends to increase until L$_{s}$ \~{}
40{\deg}, when it stabilizes around 6-8 {\times} 10$^{9}$
cm$^{-3}$. After southern winter solstice (L$_{s}$ \~{}
100{\deg}), the peak abundance starts decreasing again, and this ozone
layer is no longer detected after L$_{s}$ \~{} 130{\deg}. A recent
model (Lefèvre et al., 2004) predicted the presence of these
ozone layers, the altitude one being only present at night. Though the
agreement between model and observations is quite good, this nocturnal
altitude layer is present in SPICAM data over a less extended period
than predicted. Though a possible role of heterogeneous chemistry is not
excluded, this difference is probably linked to the seasonal evolution
of the vertical distribution of water vapor.
}},
doi = {10.1029/2005JE002643},
adsurl = {http://cdsads.u-strasbg.fr/abs/2006JGRE..111.9S05L},
localpdf = {REF/2006JGRE..111.9S05L.pdf},
adsnote = {Provided by the SAO/NASA Astrophysics Data System}
}
@article{2006Icar..183..403M,
author = {{Montmessin}, F. and {Bertaux}, J.-L. and {Quémerais}, E. and
{Korablev}, O. and {Rannou}, P. and {Forget}, F. and {Perrier}, S. and
{Fussen}, D. and {Lebonnois}, S. and {Rébérac}, A. and
{Dimarellis}, E.},
title = {{Subvisible CO $_{2}$ ice clouds detected in the mesosphere of Mars}},
journal = {\icarus},
year = 2006,
volume = 183,
pages = {403-410},
abstract = {{The formation of CO $_{2}$ ice clouds in the upper atmosphere of
Mars has been suggested in the past on the basis of a few temperature
profiles exhibiting portions colder than CO $_{2}$ frost point.
However, the corresponding clouds were never observed. In this paper, we
discuss the detection of the highest clouds ever observed on Mars by the
SPICAM ultraviolet spectrometer on board Mars Express spacecraft.
Analyzing stellar occultations, we detected several mesospheric detached
layers at about 100 km in the southern winter subtropical latitudes, and
found that clouds formed where simultaneous temperature measurements
indicated that CO $_{2}$ was highly supersaturated and probably
condensing. Further analysis of the spectra reveals a cloud opacity in
the subvisible range and ice crystals smaller than 100 nm in radius.
These layers are therefore similar in nature as the noctilucent clouds
which appear on Earth in the polar mesosphere. We interpret these
phenomena as CO $_{2}$ ice clouds forming inside supersaturated
pockets of air created by upward propagating thermal waves. This
detection of clouds in such an ultrararefied and supercold atmosphere
raises important questions about the martian middle-atmosphere dynamics
and microphysics. In particular, the presence of condensates at such
high altitudes begs the question of the origin of the condensation
nuclei.
}},
doi = {10.1016/j.icarus.2006.03.015},
adsurl = {http://cdsads.u-strasbg.fr/abs/2006Icar..183..403M},
localpdf = {REF/2006Icar..183..403M.pdf},
adsnote = {Provided by the SAO/NASA Astrophysics Data System}
}
@article{2006Icar..183..396F,
author = {{Fast}, K. and {Kostiuk}, T. and {Hewagama}, T. and {A'Hearn}, M.~F. and
{Livengood}, T.~A. and {Lebonnois}, S. and {Lefèvre}, F.
},
title = {{Ozone abundance on Mars from infrared heterodyne spectra. II. Validating photochemical models}},
journal = {\icarus},
year = 2006,
volume = 183,
pages = {396-402},
abstract = {{Ozone is an important observable tracer of martian photochemistry,
including odd hydrogen (HO $_{x}$) species important to the
chemistry and stability of the martian atmosphere. Infrared heterodyne
spectroscopy with spectral resolution {\ges}10 provides the only
ground-based direct access to ozone absorption features in the martian
atmosphere. Ozone abundances were measured with the Goddard Infrared
Heterodyne Spectrometer and the Heterodyne Instrument for Planetary Wind
and Composition at the NASA Infrared Telescope Facility on Mauna Kea,
Hawai'i. Retrieved total ozone column abundances from various latitudes
and orbital positions ( L=40{\deg}, 74{\deg}, 102{\deg}, 115{\deg},
202{\deg}, 208{\deg}, 291{\deg}) are compared to those predicted by the
first three-dimensional gas phase photochemical model of the martian
atmosphere [Lefèvre, F., Lebonnois, S., Montmessin, F., Forget,
F., 2004. J. Geophys. Res. 109, doi:10.1029/2004JE002268. E07004].
Observed and modeled ozone abundances show good agreement at all
latitudes at perihelion orbital positions ( L=202{\deg}, 208{\deg},
291{\deg}). Observed low-latitude ozone abundances are significantly
higher than those predicted by the model at aphelion orbital positions (
L=40{\deg}, 74{\deg}, 115{\deg}). Heterogeneous loss of odd hydrogen onto
water ice cloud particles would explain the discrepancy, as clouds are
observed at low latitudes around aphelion on Mars.
}},
doi = {10.1016/j.icarus.2006.03.012},
adsurl = {http://cdsads.u-strasbg.fr/abs/2006Icar..183..396F},
localpdf = {REF/2006Icar..183..396F.pdf},
adsnote = {Provided by the SAO/NASA Astrophysics Data System}
}
@article{2005Icar..179...43E,
author = {{Encrenaz}, T. and {Bézard}, B. and {Owen}, T. and {Lebonnois}, S. and
{Lefèvre}, F. and {Greathouse}, T. and {Richter}, M. and
{Lacy}, J. and {Atreya}, S. and {Wong}, A.~S. and {Forget}, F.
},
title = {{Infrared imaging spectroscopy of Mars: H $_{2}$O mapping and determination of CO $_{2}$ isotopic ratios}},
journal = {\icarus},
year = 2005,
volume = 179,
pages = {43-54},
abstract = {{High-resolution infrared imaging spectroscopy of Mars has been achieved
at the NASA Infrared Telescope Facility (IRTF) on June 19-21, 2003,
using the Texas Echelon Cross Echelle Spectrograph (TEXES). The
areocentric longitude was 206{\deg}. Following the detection and mapping
of hydrogen peroxide H $_{2}$O $_{2}$ [Encrenaz et al.,
2004. Icarus 170, 424-429], we have derived, using the same data set, a
map of the water vapor abundance. The results appear in good overall
agreement with the TES results and with the predictions of the Global
Circulation Model (GCM) developed at the Laboratory of Dynamical
Meteorology (LMD), with a maximum abundance of water vapor of
3{\plusmn}1.5{\times}10(17{\plusmn}9 pr-{$\mu$}m). We have searched for CH
$_{4}$ over the martian disk, but were unable to detect it. Our
upper limits are consistent with earlier reports on the methane
abundance on Mars. Finally, we have obtained new measurements of CO
$_{2}$ isotopic ratios in Mars. As compared to the terrestrial
values, these values are: ( $^{18}$O/ $^{17}$O)[M/E] = 1.03
{\plusmn} 0.09; ( $^{13}$C/ $^{12}$C)[M/E] = 1.00 {\plusmn}
0.11. In conclusion, in contrast with the analysis of Krasnopolsky et
al. [1996. Icarus 124, 553-568], we conclude that the derived martian
isotopic ratios do not show evidence for a departure from their
terrestrial values.
}},
doi = {10.1016/j.icarus.2005.06.022},
adsurl = {http://cdsads.u-strasbg.fr/abs/2005Icar..179...43E},
localpdf = {REF/2005Icar..179...43E.pdf},
adsnote = {Provided by the SAO/NASA Astrophysics Data System}
}
@article{2004Icar..170..424E,
author = {{Encrenaz}, T. and {Bézard}, B. and {Greathouse}, T.~K. and
{Richter}, M.~J. and {Lacy}, J.~H. and {Atreya}, S.~K. and {Wong}, A.~S. and
{Lebonnois}, S. and {Lefèvre}, F. and {Forget}, F.},
title = {{Hydrogen peroxide on Mars: evidence for spatial and seasonal variations}},
journal = {\icarus},
keywords = {Mars, atmosphere, composition, Infrared observations, Photochemistry},
year = 2004,
volume = 170,
pages = {424-429},
abstract = {{Hydrogen peroxide (H $_{2}$O $_{2}$) has been suggested as a
possible oxidizer of the martian surface. Photochemical models predict a
mean column density in the range of 10 $^{15}$-10 $^{16}$ cm
$^{-2}$. However, a stringent upper limit of the H $_{2}$O
$_{2}$ abundance on Mars (9{\times}10 $^{14}$ cm
$^{-2}$) was derived in February 2001 from ground-based infrared
spectroscopy, at a time corresponding to a maximum water vapor abundance
in the northern summer (30 pr. {$\mu$}m, Ls=112{\deg}). Here we report the
detection of H $_{2}$O $_{2}$ on Mars in June 2003, and its
mapping over the martian disk using the same technique, during the
southern spring ( Ls=206{\deg}) when the global water vapor abundance was
{\tilde}10 pr. {$\mu$}m. The spatial distribution of H $_{2}$O
$_{2}$ shows a maximum in the morning around the sub-solar
latitude. The mean H $_{2}$O $_{2}$ column density
(6{\times}10 $^{15}$ cm $^{-2}$) is significantly greater
than our previous upper limit, pointing to seasonal variations. Our new
result is globally consistent with the predictions of photochemical
models, and also with submillimeter ground-based measurements obtained
in September 2003 ( Ls=254{\deg}), averaged over the martian disk (Clancy
et al., 2004, Icarus 168, 116-121).
}},
doi = {10.1016/j.icarus.2004.05.008},
adsurl = {http://cdsads.u-strasbg.fr/abs/2004Icar..170..424E},
localpdf = {REF/2004Icar..170..424E.pdf},
adsnote = {Provided by the SAO/NASA Astrophysics Data System}
}
@article{2004JGRE..109.7004L,
author = {{Lefèvre}, F. and {Lebonnois}, S. and {Montmessin}, F. and
{Forget}, F.},
title = {{Three-dimensional modeling of ozone on Mars}},
journal = {Journal of Geophysical Research (Planets)},
keywords = {Atmospheric Composition and Structure: Middle atmosphere-constituent transport and chemistry (3334), Planetology: Solid Surface Planets: Atmospheres-composition and chemistry, Planetology: Solar System Objects: Mars},
year = 2004,
volume = 109,
eid = {E07004},
pages = {7004},
abstract = {{We present the first three-dimensional model simulations of ozone on
Mars. The model couples a state-of-the-art gas-phase photochemical
package to the general circulation model developed at Laboratoire de
Météorologie Dynamique (LMD). The results do not
contradict the classical picture of a global anticorrelation between the
ozone (O$_{3}$) and water vapor columns. However, the quantitative
approach shows significant departures from this relationship, related to
substantial orbital variations in the O$_{3}$ vertical
distribution. Over the period L$_{s}$ = 180{\deg}-330{\deg},
low-latitude to midlatitude O$_{3}$ is essentially confined below
20 km, has a weak diurnal cycle, and is largely modulated by topography.
During the rest of the year (L$_{s}$ = 330{\deg}-180{\deg}) the
model predicts the formation of an O$_{3}$ layer at 25-70 km
altitude, characterized by nighttime densities about one order of
magnitude larger than during the day. Throughout the year, high-latitude
O$_{3}$ peaks near the surface and reaches maximum integrated
amounts (\~{}40 {$\mu$}m-atm) in the winter polar vortex, with considerable
(30 to 50\%) dynamically induced day-to-day variations. The most
stringent comparison to date with O$_{3}$ observational data
reveals contrasted results. A good quantitative agreement is found in
the postperihelion period (L$_{s}$ = 290{\deg}-10{\deg}), but the
model fails to reproduce O$_{3}$ columns as large as those
measured near aphelion (L$_{s}$ = 61{\deg}-67{\deg}). Current
uncertainties in absorption cross sections and gas-phase kinetics data
do not seem to provide credible explanations to explain this
discrepancy, which may suggest the existence of heterogeneous processes.
}},
doi = {10.1029/2004JE002268},
adsurl = {http://cdsads.u-strasbg.fr/abs/2004JGRE..109.7004L},
localpdf = {REF/2004JGRE..109.7004L.pdf},
adsnote = {Provided by the SAO/NASA Astrophysics Data System}
}