The Mars Climate Database, Version 6.1
E. Millour1, F. Forget 1, A. Spiga1, T. Pierron1, A. Bierjon1, L. M ontabone1,2, M . Vals 1,3, F. Lefèvre3, F. M ontmessin3, J.-Y.
Chaufray 3, M . A. López-Valverde4, F. González-Galindo4, S. R. Lewis 5, P. L. Read6, M .-C. Desjean7, F. Cipriani8 and the
M CD development team.
1
Laboratoire de M étéorologie Dynamique (LM D), IPSL, Sorbonne Université, Paris, France, (millour@lmd.jussieu.fr), 2Space
Science Institute, Boulder, USA, 3Laboratoire Atmosphères, M ilieux, Observations Spatiales (LATM OS), IPSL, Paris,
France, 4Instituto de Astrofisica de Andalucia (IAA-CSIC), Granada, Spain, 5Department of Physical Sciences, The Open
University, M ilton Keynes, UK, 6Atmospheric, Oceanic and Planetary Physics (AOPP), Oxford, UK, 7Centre National
D’Etudes Spatiales (CNES), Toulouse, France, 8European Space Research and Technology Center (ESTEC), Noordwijk, The
Netherlands

Introduction:
The Mars Climate Database (MCD) is a database
of meteorological fields derived from General Circulation Model (GCM) numerical simulations of the Martian atmosphere and validated using available observational data. The MCD includes complementary
post-processing schemes such as high spatial resolution interpolation of environmental data and means of
reconstructing the variability thereof.
The GCM that is used to create the MCD data is
developed at Laboratoire de Météorologie Dynamique du CNRS (Paris, France) [1] in collaboration
with LATMOS (Paris, France), the Open University
(UK), the Oxford University (UK) and the Instituto de
Astrofisica de Andalucia (Spain) with support from
the European Space Agency (ESA) and the Centre
National d'Etudes Spatiales (CNES).
The latest version of the MCD, version 5.3 [2],
was released in July 2017, and at the time of writing of
this abstract we are working on MCDv6.1, which we
will release in May 2022. This new version will benefit
from all the recent developments and improvements
[1,3-5] in the GCM’s physics package.
The MCD is freely distributed and intended to be
useful and used in the framework of engineering applications as well as in the context of scientific studies which require accurate knowledge of the state of
the Martian atmosphere. Over the years, various versions of the MCD have been released and handed to
more than 400 teams around the world.
Current applications include entry descent and
landing (EDL) studies for future missions, investigations of some specific Martian issues (via coupling of
the MCD with homemade codes), analysis of observations (Earth-based as well as with various instruments onboard Mars Express, Mars Reconnaissance
Orbiter, Maven, Trace Gas Orbiter, Hope),...
The MCD is freely available upon request via an
online form on the dedicated website: http://www-

mars.lmd.jussieu.fr which moreover includes a convenient web interface for quick looks.

Figure 1: Illustrative example of the online Mars
Climate Database web interface and its plotting capabilities.
Overview of MCD contents:
The MCD provides mean values and statistics of
the main meteorological variables (atmospheric temperature, density, pressure and winds) as well as atmospheric composition (including dust and water
vapor and ice content), as the GCM from which the
datasets are obtained includes water cycle, chemistry, and ionosphere models. The database extends up
to and including the thermosphere (~350km). Since
the influence of Extreme Ultra Violet (EUV) input from
the sun is significant in the latter, 3 EUV scenarios
(solar minimum, average and maximum inputs) account for the impact of the various states of the solar
cycle.
As the main driver of the Martian climate is the
dust loading of the atmosphere, the MCD provides
climatologies over a series of synthetic dust scenarios: standard year (a.k.a. climatology), cold (i.e: low
dust), warm (i.e: dusty atmosphere) and dust storm,
These are derived from home-made, instrumentderived (TES, THEMIS, MCS, MERs), dust climatology of the last 12 Martian years [6]. In addition, we
also provide additional “add-on” scenarios which
focus on individual Martian Years (from MY 24 to
MY 35) for users more interested in more specific

climatologies than the MCD baseline scenarios.
In practice the MCD provides users with:
 Mean values and statistics of main meteorological variables (atmospheric temperature,
density, pressure and winds), as well as surface pressure and temperature, CO2 ice cover, thermal and solar radiative fluxes, dust
column opacity and mixing ratio, [H20] vapor
and ice concentrations, along with concentrations of many species: [CO], [O2], [O],
[N2], [Ar], [H2], [O3], [H] ..., as well as electrons mixing ratios. Column densities of these
species are also given.
 Physical processes in the Planetary Boundary Layer (PBL), such as PBL height, minimum
and maximum vertical convective winds in
the PBL, surface wind stress and sensible
heat flux.
 The possibility to reconstruct realistic conditions by combining the provided climatology
with additional large scale (derived from Empirical Orthogonal Functions extracted from
the GCM runs) and small scale perturbations
(gravity waves).
 •
Dust mass mixing ratio, along with
estimated dust effective radius and dust
deposition rate on the surface are provided.
 A high resolution mode which combines high
resolution (32 pixel/degree) MOLA topography records and Insight pressure records
with raw lower resolution GCM results to
yield, within the restriction of the procedure,
high resolution values of atmospheric variables (pressure, but also temperature and
winds via dedicated schemes).
Updates and improvements in MCDv6.1:
Compared to MCDv5.3, and aside from the fact
that the MCD fields have been computed using the
latest version of the LMD GCM, noteworthy improvements and additions in this new version of the
MCD include:
 Reference pressure records for the high res olution mode correction now rely on Insight
measurements rather than Viking lander 1
ones.
 An implementation of extracting dust opacities from the daily maps used by the GCM rather than providing the climatological (based
on the Ls=30° monthly average) value, as illustrated in Figure 2.
 Improved estimations of dust deposition
rates using the aforementioned daily variations of atmospheric dust opacity (see Figure
3).
 Computation of the local slope (inclination
and orientation) properties.




Computation of the solar irradiance on local
slopes, including in high resolution mode.
Addition of a slope winds scheme to account
for local topographical effects in high resolution mode (see figure 5).

Figure 2: Illustrative example of the dust column
visible optical depth over the year at the Insight landing site, for various dust scenarios and using either
the (MCDv5.3-style) climatological dust scenario or
the “high resolution” (MCDv6.1-style) extraction of
day-to-day varying opacities.

Figure 3: Estimated dust deposition rates on a
flat surface at the Insight landing site location, based
on the dust opacity extraction method (see figure2).
The higher resolution outputs are for the scheme
implemented in MCDv6.1

Figure 4: Insolation at 6am (top) and 8 am (bottom) around Valles Marineris, as recomputed with
MCDv6.1’s high resolution mode. Continued on next
page for later times of day.

References:
[1] Forget et al. (2022), this conference.
[2] Millour et al. (2018), “The Mars Climate Database (version 5.3) », From Mars Express to ExoMars
Scienfic Workshop, 2è-28 February 2018, ESAC Madrid, Spain.
[3] Bierjon et al. (2022), this conference.
[4] Pierron et al. (2022), this conference.
[5] Liu et al. (2022), this conference.
[6] Montabone et al. (2022), this conference.

Figure 4 (continued): Insolation at, from top to
bottom, 10am, 12am, 2pm and 4pm around Valles Marineris.

Figure 5: winds at 20m above the surface above
Oxia Planum at night (1am) and day (1pm), illustrating
the anabatic and katabatic winds produced by the
MCDv6.1 slope wind scheme.