OpenMARS
OpenMARS (Open access to Mars Assimilated Remote Soundings) is a reanalysis dataset of the Martian atmosphere and surface. It combines observations made by several Mars spacecraft with a general circulation model to produce a continuous, gridded estimate of past Martian weather.[1] It was developed at the Open University in the United Kingdom and is distributed through the university's research-data repository.[2]
Production and coverage
[edit]Reanalysis uses data assimilation to combine incomplete observations with a numerical atmosphere model. The model supplies a physically consistent atmospheric state between spacecraft measurements, while observations correct the simulated state when and where they are available.[1]The original OpenMARS release covered 1999–2015, from Mars Year 24 into Mars Year 32. It assimilated temperature and dust observations from the Thermal Emission Spectrometer on Mars Global Surveyor and from the Mars Climate Sounder on the Mars Reconnaissance Orbiter. Separate products also incorporated water-vapour retrievals from those instruments and ozone observations by SPICAM on Mars Express.[1] Later versions of the collection have extended and revised the available products.[2]Standard output includes atmospheric temperature and winds, surface pressure and temperature, column dust optical depth, and surface carbon dioxide ice. The published dataset uses a grid spacing of 5 degrees in latitude and longitude, 35 vertical levels extending to about 105 kilometres, and output intervals of two Martian hours.[3]
Applications
[edit]OpenMARS is used to study atmospheric circulation, waves and dust storms over time periods longer than an individual spacecraft observation. Hinson and Wilson compared the reanalysis with independent off-nadir measurements from the Mars Climate Sounder before using it to analyse the response of stationary Rossby waves to regional dust storms.[4]Li and colleagues applied an eddy-detection and tracking method to OpenMARS wind fields. They used the resulting distribution of cyclones and anticyclones to examine seasonal patterns and to compare candidate sampling areas for the planned Tianwen-3 mission.[3] OpenMARS has also been used to investigate the propagation of Mars's northern annular mode and its relationship with atmospheric dust.[5]
Limitations
[edit]OpenMARS is a model-constrained reconstruction rather than a direct observation at every grid point. Its results depend on the coverage and retrieval characteristics of the assimilated instruments and on the assumptions of the underlying circulation model.[1] The 5-degree horizontal grid describes planetary scale circulation but cannot resolve many local or mesoscale features. In their eddy study, Li and colleagues interpolated the wind field to a finer grid but noted that small structures could still be absent from the source data.[3] Comparisons with observations or other Mars reanalyses are therefore used to test whether particular features are robust.[4]
See also
[edit]References
[edit]- 1 2 3 4 Holmes, James A.; Lewis, Stephen R.; Patel, Manish R. (2020). "OpenMARS: A global record of martian weather from 1999 to 2015". Planetary and Space Science. 188 104962. doi:10.1016/j.pss.2020.104962.
- 1 2 "OpenMARS database". Open Research Data Online. The Open University. Retrieved 14 September 2026.
- 1 2 3 Li, Bo; Qu, Shaojie; Ling, Zongcheng; Chen, Shengbo (2024). "A preliminary study on the identification and spatio-temporal characteristics of Martian atmospheric eddies". Journal of Geophysical Research: Planets. 129 (3) e2023JE007937. doi:10.1029/2023JE007937.
- 1 2 Hinson, David P.; Wilson, R. John (2024). "Dust-storm forcing of Rossby waves on Mars". Icarus. 412 115998. doi:10.1016/j.icarus.2024.115998.
- ↑ Battalio, J. Michael; Lora, Juan M.; Lubis, Sandro W.; Hassanzadeh, Pedram (2025). "Propagation and periodicity of Mars's northern annular mode modulates the dust cycle". Geophysical Research Letters. 52 (6) e2024GL112814. doi:10.1029/2024GL112814.