Hydrogen escape from Mars enhanced by deep convection in dust storms

Abstract

Present-day water loss from Mars provides insight into Mars’s past habitability1,2,3. Its main mechanism is thought to be Jeans escape of a steady hydrogen reservoir sourced from odd-oxygen reactions with near-surface water vapour2, 4,5. The observed escape rate, however, is strongly variable and correlates poorly with solar extreme-ultraviolet radiation flux6,7,8, which was predicted to modulate escape9. This variability has recently been attributed to hydrogen sourced from photolysed middle atmospheric water vapour10, whose vertical and seasonal distribution is only partly characterized and understood11,12,13. Here, we report multi-annual observational estimates of water content and dust and water transport to the middle atmosphere from Mars Climate Sounder data. We provide strong evidence that the transport of water vapour and ice to the middle atmosphere by deep convection in Martian dust storms can enhance hydrogen escape. Planet-encircling dust storms can raise the effective hygropause (where water content rapidly decreases to effectively zero) from 50 to 80 km above the areoid (the reference equipotential surface). Smaller dust storms contribute to an annual mode in water content at 4050 km that may explain seasonal variability in escape. Our results imply that Martian atmospheric chemistry and evolution can be strongly affected by the meteorology of the lower and middle atmosphere of Mars.

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Fig. 1: Hydrogen escape and explanatory factors during MY 28.
Fig. 2: Water vapour and water transport during Ls = 269–274°.
Fig. 3: Hydrogen escape and explanatory factors during MY 33.
Fig. 4: Impact of the MY 29 Arsia Mons spiral cloud (Ls = 177.05°) on atmospheric water.

References

  1. 1.

    Carr, M. H. & Head, J. W. III Oceans on Mars: an assessment of the observational evidence and possible fate. J. Geophys. Res. 108, 5042 (2003).

    Article  Google Scholar 

  2. 2.

    Zahnle, K., Haberle, R. M., Catling, D. C. & Kasting, J. F. Photochemical instability of the ancient Martian atmosphere. J. Geophys. Res. 113, E11004 (2008).

    Article  ADS  Google Scholar 

  3. 3.

    Villanueva, G. L. et al. Strong water isotopic anomalies in the Martian atmosphere: probing current and ancient reservoirs. Science 348, 218–221 (2015).

    Article  ADS  Google Scholar 

  4. 4.

    McElroy, M. B., Kong, T. Y. & Yung, Y. L. Photochemistry and evolution of Mars’ atmosphere: a Viking perspective. J. Geophys. Res. 82, 4379–4388 (1977).

    Article  ADS  Google Scholar 

  5. 5.

    Lewis, J. S. Physics and Chemistry of the Solar System 2nd edn (Academic Press, Cambridge, MA, 2004).

    Google Scholar 

  6. 6.

    Clarke, J. T. et al. A rapid decrease of the hydrogen corona of Mars. Geophys. Res. Lett. 41, 8013–8020 (2014).

    Article  ADS  Google Scholar 

  7. 7.

    Bhattacharya, D., Clarke, J. T., Bertaux, J.-L., Chaufray, J.-Y. & Mayyasi, M. A strong seasonal dependence in the Martian hydrogen exosphere. Geophys. Res. Lett. 42, 8678–8685 (2015).

    Article  ADS  Google Scholar 

  8. 8.

    Chaffin, M. S. et al. Unexpected variability of Martian hydrogen escape. Geophys Res. Lett. 41, 314–320 (2014).

    Article  ADS  Google Scholar 

  9. 9.

    Chaufray, J.-Y. et al. Variability of the hydrogen in the Martian atmosphere as simulated by a 3D atmosphere–exosphere coupling. Icarus 245, 282–294 (2015).

    Article  ADS  Google Scholar 

  10. 10.

    Chaffin, M. S., Deighan, J., Schneider, N. M. & Stewart, A. I. F. Elevated atmospheric escape of hydrogen from Mars induced by high-altitude water. Nat. Geosci. 10, 174–178 (2017).

    Article  ADS  Google Scholar 

  11. 11.

    Maltagliati, L. et al. Annual survey of water vapor vertical distribution and water–aerosol coupling in the Martian atmosphere observed by SPICAM/MEx solar occultations. Icarus 223, 942–962 (2013).

    Article  ADS  Google Scholar 

  12. 12.

    Clancy, R. T. et al. Vertical profiles of Mars 1.27 μm O2 dayglow from MRO CRISM limb spectra: seasonal/global behaviors, comparisons to LMD GCM simulations, and a global definition for Mars water vapor profiles. Icarus 293, 132–156 (2017).

    Article  ADS  Google Scholar 

  13. 13.

    Montmessin, F. et al. SPICAM on Mars Express: a 10 year in-depth survey of the Martian atmosphere. Icarus 297, 195–216 (2017).

    Article  ADS  Google Scholar 

  14. 14.

    Kleinböhl., A. et al. Mars Climate Sounder limb profile retrieval of atmospheric temperature, pressure, and dust and water opacity. J. Geophys. Res. 114, E10006 (2009).

    Article  ADS  Google Scholar 

  15. 15.

    Toigo, A. D., Smith, M. D., Seelos, F. P. & Murchie, S. L. J. Geophys. Res. Planets 118, 89–104 (2013).

    Article  ADS  Google Scholar 

  16. 16.

    Halekas, J. S. Seasonal variability of the hydrogen exosphere of Mars. J. Geophys. Res. Planets 122, 901–911 (2017).

    Article  ADS  Google Scholar 

  17. 17.

    Clancy, R. T. et al. An intercomparison of ground-based millimeter, MGS TES, and Viking atmospheric temperature measurements: seasonal and interannual variability of temperatures and dust loading in the global Mars atmosphere. J. Geophys. Res. 105, 9553–9571 (2000).

    Article  ADS  Google Scholar 

  18. 18.

    Piqueux, S., Byrne, S., Titus, T., Hansen, C. & Kieffer, H. Enumeration of Mars years and seasons since the beginning of telescopic exploration. Icarus 251, 164–180 (2014).

    Article  Google Scholar 

  19. 19.

    Wang, H. & Richardson, M. I. The origin, evolution, and trajectory of large dust storms on Mars during Mars years 24–30 (1999–2011). Icarus 251, 112–127 (2015).

    Article  ADS  Google Scholar 

  20. 20.

    Fedorova, A. et al. Water vapor in the middle atmosphere of Mars during the 2007 global dust storm. Icarus 300, 440–457 (2018).

    Article  ADS  Google Scholar 

  21. 21.

    Montmessin, F., Forget, F., Rannou, P., Cabane, M. & Haberle, R. M. Origin and role of water ice clouds in the Martian water cycle as inferred from a general circulation model. J. Geophys. Res. Planets 109, E10004 (2004).

    Article  ADS  Google Scholar 

  22. 22.

    Cantor, B., Malin, M. & Edgett, K. S. Multiyear Mars Orbiter Camera (MOC) observations of repeated Martian weather phenomena during the northern summer season. J. Geophys. Res. 107, 5014 (2002).

    Article  Google Scholar 

  23. 23.

    Rafkin, S. C. R., Maria, M. R. V. S. & Michaels, T. I. Simulation of the atmospheric thermal circulation of a Martian volcano using a mesoscale numerical model. Nature 419, 697–699 (2002).

    Article  ADS  Google Scholar 

  24. 24.

    Heavens, N. G. et al. Extreme detached dust layers near Martian volcanoes: evidence for dust transport by mesoscale circulations forced by high topography. Geophys. Res. Lett. 42, 3730–3738 (2015).

    Article  ADS  Google Scholar 

  25. 25.

    Head, J. W. et al. Tropical to mid-latitude snow and ice accumulation, flow and glaciation on Mars. Nature 434, 346–351 (2005).

    Article  ADS  Google Scholar 

  26. 26.

    Mischna, M. A. & Richardson, M. I. A reanalysis of water abundances in the Martian atmosphere at high obliquity. Geophys. Res. Lett. 32, L03201 (2005).

    Article  ADS  Google Scholar 

  27. 27.

    Newman, C. E., Lewis, S. R. & Read, P. L. The atmospheric circulation and dust activity in different orbital epochs on Mars. Icarus 174, 135–160 (2005).

    Article  ADS  Google Scholar 

  28. 28.

    Bougher, S. W. et al. The structure and variability of Mars dayside thermosphere from MAVEN NGIMS and IUVS measurements: seasonal and solar activity trends in scale heights and temperatures. J. Geophys. Res. Space Phys. 122, 1296–1313 (2017).

    Article  ADS  Google Scholar 

  29. 29.

    Chaffin, M. S. et al. Three-dimensional structure in the Mars H corona revealed by IUVS on MAVEN. Geophys. Res. Lett. 42, 9001–9008 (2015).

    Article  ADS  Google Scholar 

  30. 30.

    Kleinböhl, A., Friedson, A. J. & Schofield, J. T. Two-dimensional radiative transfer for the retrieval of limb emission measurements in the Martian atmosphere. J. Quant. Spectrosc. Radiat. Transfer 187, 511–522 (2017).

    Article  ADS  Google Scholar 

  31. 31.

    Heavens, N. G. et al The vertical distribution of dust in the Martian atmosphere during northern spring and summer: observations by the Mars Climate Sounder and analysis of zonal average vertical dust profiles. J. Geophys. Res. 116, E04003 (2011).

    ADS  Google Scholar 

  32. 32.

    Zurek, R. W. & Smrekar, S. E. An overview of the Mars Reconnaissance Orbiter (MRO) science mission. J. Geophys. Res. 112, E05S01 (2007).

    Article  ADS  Google Scholar 

  33. 33.

    Murphy, D. M. & Koop, T. Review of the vapour pressures of ice and supercooled water for atmospheric applications. Q. J. R. Meteor. Soc. 131, 1359–1365 (2005).

    Article  Google Scholar 

  34. 34.

    McCleese, D. J. et al. Structure and dynamics of the Martian lower and middle atmosphere as observed by the Mars Climate Sounder: seasonal variations in zonal mean temperature, dust, and water ice aerosols. J. Geophys Res. 115, E12016 (2010).

    Article  ADS  Google Scholar 

  35. 35.

    Conrath, B. J. Thermal structure of the Martian atmosphere during the dissipation of the dust storm of 1971. Icarus 24, 36–46 (1975).

    Article  ADS  Google Scholar 

  36. 36.

    Heavens, N. G. et al Seasonal and diurnal variability of detached dust layers in the tropical Martian atmosphere. J. Geophys. Res. Planets 119, 1748–1774 (2014).

    Article  ADS  Google Scholar 

  37. 37.

    Boxe, C. S. et al. Adsorbed water and thin liquid films on Mars. Int. J. Astrobiol. 11, 169–175 (2012).

    Article  Google Scholar 

  38. 38.

    Malin, M. C., Cantor, B. A. & Britton, A. W. MRO MARCI Weekly Weather Reports (2007–2017); http://www.msss.com/msss_images/subject/weather_reports.html

  39. 39.

    Kass, D. M., Kleinböhl, A., McCleese, D. J., Schofield, J. T. & Smith, M. D. Interannual similarity in the Martian atmosphere during the dust storm season. Geophys. Res. Lett. 43, 6111–6118 (2016).

    Article  ADS  Google Scholar 

Download references

Acknowledgements

This work was supported by NASA’s Mars Data Analysis and Nexus for Exoplanet System Science programmes (NNX14AM32G and NNX15AE05G to N.G.H. and NNN13D465T to A.K.). Work at the Jet Propulsion Laboratory, California Institute of Technology is performed under contract with NASA. The authors thank A. D. Toigo for providing CRISM data.

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N.G.H. and A.K. conceived and designed the study with input from M.S.C. N.G.H. designed and analysed the dust and water vapour flux diagnoses and analysed the inferred water vapour information. A.K. designed the inferred water vapour diagnosis. J.S.H. processed and interpreted hydrogen corona observations from MAVEN. All authors assisted N.G.H. with the preparation of the manuscript.

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Correspondence to Nicholas G. Heavens.

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Supplementary Table 1, Supplementary Figures 1–4.

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Heavens, N.G., Kleinböhl, A., Chaffin, M.S. et al. Hydrogen escape from Mars enhanced by deep convection in dust storms. Nat Astron 2, 126–132 (2018). https://doi.org/10.1038/s41550-017-0353-4

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