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As a fan of exometeorology (the study of atmospheres of other planets), I scanned through a whitepaper Measuring Mars Atmospheric Winds from Orbit which says

Measurements of Mars atmospheric winds from orbit would dramatically advance our understanding of Mars and help prepare for human exploration of the Red Planet. Multiple instrument candidates are in development and will be ready for flight in the next decade. We urge the Decadal Survey to make these measurements a priority for 2023-2032.

This gives me the impression that our knowledge about spatial wind speed distribution on Mars are scarce. But what about indirect methods to determine prevailing wind speeds at different locations on Mars?

Some years ago I attended a lecture by Prof. Hans Herrmann showing that the shapes of Barchan sand dunes might be a good candidate for indirectly determining the prevailing winds of Mars. However, I could not find any survey study which would analyze the complete observed Mars surface for dunes and map the average wind speed on Mars. Is there such an effort already on the way? Are there any arguments against such a Mars-dune-windspeed-survey?

Further reading

B--rian
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  • At first thought, angle of repose should win out, regardless of wind speed. But there could easily be some effect I'm missing here. Ref: https://en.wikipedia.org/wiki/Angle_of_repose – Wayfaring Stranger Dec 08 '20 at 17:00
  • @WayfaringStranger Your comment reminded me that I forgot the essential keyword, which I just edited in: The theory holds on Barchan dunes. More on the involved process: https://en.m.wikipedia.org/wiki/Saltation_(geology) – B--rian Dec 08 '20 at 19:49
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    I know nothing of dunes but that doesn't stop me from asking questions about them. In Earth Science SE I'd asked What produces these distinct shapes in the Rub' al Khali seen from space? now searching for "Barchan" there returns The grains of the parabolic dunes which makes me wonder if there's a better answer to my question. – uhoh Dec 09 '20 at 04:28
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    Great question - and difficult to answer. To my knowledge there's no definitive answer on it - but that doesn't say there's no PhD, MSc or BSc thesis on the topic which might answer it more profoundly than your research already reveals. Problem is also that a lot of assumption go into modelling wind speeds based on morphological observations, including the different grain behaviour in different atmosphere, temperature, insolation and gravity – planetmaker Dec 20 '20 at 11:34
  • It seems to me that you would need a very good model for how transport speeds/mechanisms work with Mars' dust, atmosphere, and gravity, and then you would have to track those which generally require HiRISE scales. Just looking at dune shapes/directions wouldn't get you that information. If you want wind DIRECTION only, then we have plenty of info from images. – Stuart Robbins Sep 01 '21 at 04:04
  • I would appreciate if anyone of you could write an answer (draft), so that I could reward my points to somebody... – B--rian Sep 07 '21 at 07:06

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