RoadMap – from Lab to Space: Applying an updated dust lifting equation in the
GEM-Mars GCM
L. Neary (lori.neary@aeronomie.be), F. Daerden (Royal Belgian Institute for Space Aeronomy, Brussels, BE),
G. Wurm, T. Becker, J. Teiser (University of Duisburg-Essen (UDE), Duisburg, DE), J. Merrison, K. Rasmussen, A. Waza (Aarhus University (AU), Aarhus, DK), O. Munoz, J. Martikainen, J. C. Gomez Martin, F.
Moreno (Instituto de Astrofísica de Andalucía (CSIC-IAA), Granada, ES), T. Jardiel, M. Peiteado, A. C. Caballero (Instituto de Cerámica y Vidrio (CSIC-ICV), Madrid, ES), J. T. Erwin, Z. Filmon, A. Piccialli, L.
Trompet, Y. Willame, A. C. Vandaele (Royal Belgian Institute for Space Aeronomy, Brussels, BE)
Introduction: The aim of the Horizon 2020
RoadMap project (http://roadmap.aeronomie.be) is
to better understand the role and impact of dust and
clouds on the Martian atmosphere through an integrated approach involving lab measurements, micromodelling, global climate modelling and remote
sensing observations.
One of the specific goals set out for the project is
to improve our understanding of the mechanisms
responsible for dust lifting and transport. When dust
is lifted from the surface and transported aloft, it has
a significant effect on the temperature and circulation of the atmosphere. Several processes can lift
dust from the surface, including saltation and dust
devils.
Martian analogue soil: Three samples are used
in the RoadMap project to provide a wide range of
spectral and compositional variability. These are JSC
Mars-1 (Johnson Space Center regolith simulant) in
2 different particle sizes, MMS-2 (Mojave Mars
Simulant) and MGS-1 (Mars Global Simulant). The
analogues were received, prepared and characterized
at CSIC-ICV, then provided to the labs at CSICIAA, AU and UDE.

Figure 1 Martian dust analogues from left to
right: JSC1-Mars < 1 mm, JSC1-Mars < 250 µm,
MMS-2 and MGS-1.
Lab measurements: Preliminary lab measurements at AU and UDE using the Martian analogue
soils were performed to investigate dust resuspension/aerolization and saltation. At AU, a narrow dust
resuspension wind tunnel was constructed within
their AWTSII chamber and preliminary experiments
of saltation induced and direct wind driven dust resuspension were performed. At UDE, a setup for
impact experiments has been developed.
Figure 2 The AU sand
bed with JSC-1 dust
after wind exposure.

These experiments have contributed to an updated formulation of threshold wind stress to describe
when lifting may occur. As more experiments are
performed, the parameters used can be updated.
GCM Modelling: We test the new formulation
for threshold wind stress in a three-dimensional
Global Climate Model (GCM) for the atmosphere of
Mars, GEM-Mars [1-2]. GEM-Mars has been evaluated and applied to several recent science investigations including [3-5]. The impacts of the 2018 global
dust storm on the Martian atmosphere was explored
in [6-8].
The current formulation for dust lifting from the
surface in GEM-Mars includes the effects of saltation and dust devils. We update this implementation
with new terms derived from the lab experiments
and examine the impact on the representation of the
global dust cycle in the GCM.
Acknowledgements: This project has received
funding from the European Union’s Horizon 2020
research and innovation programme under grant
agreement No 101004052.
References:
[1] Neary L. and Daerden F. Icarus 300, 458–476
(2018)
[2] Daerden, F. et al. Icarus 326, 197–224 (2019)
[3] Smith, M. et al. Icarus 362, 114404 (2021)
[4] Bouche J. et al. Journal of Geophysical Research: Planets 126(2) (2021)
[5] Khayat A. et al. Journal of Geophysical Research: Planets 126(11) (2021)
[6] Aoki, S. et al. Journal of Geophysical Research: Planets 124(12) (2019)
[7] Neary, L. et al. Geophysical Research Letters
47, e2019GL084354 (2020)
[8] Daerden, F. et al. Journal of Geophysical
Research: Planets, e2021JE007079 (2022)