Skip to main content

Thank you for visiting You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

Dynamics of ice ages on Mars


Unlike Earth, where astronomical climate forcing is comparatively small, Mars experiences dramatic changes in incident sunlight that are capable of redistributing ice on a global scale1,2,3,4,5,6. The geographic extent of the subsurface ice found poleward of approximately ±60° latitude on both hemispheres of Mars7,8,9 coincides with the areas where ice is stable7,10,11. However, the tilt of Mars’ rotation axis (obliquity) changed considerably in the past several million years. Earlier work3,12 has shown that regions of ice stability, which are defined by temperature and atmospheric humidity, differed in the recent past from today’s, and subsurface ice is expected to retreat quickly when unstable11,12,13. Here I explain how the subsurface ice sheets could have evolved to the state in which we see them today. Simulations of the retreat and growth of ground ice as a result of sublimation loss and recharge reveal forty major ice ages over the past five million years. Today, this gives rise to pore ice at mid-latitudes and a three-layered depth distribution in the high latitudes of, from top to bottom, a dry layer, pore ice, and a massive ice sheet. Combined, these layers provide enough ice to be compatible with existing neutron and gamma-ray measurements7,8,9.

Your institute does not have access to this article

Relevant articles

Open Access articles citing this article.

Access options

Buy article

Get time limited or full article access on ReadCube.


All prices are NET prices.

Figure 1: Snapshots of the vertical ice distribution from model calculations.
Figure 2: Evolution of southern hemisphere ice over the past five million years for strongly varying atmospheric humidity.
Figure 3: Comparison with measurements by GRS onboard Mars Odyssey.


  1. Toon, O. B., Pollack, J. B., Ward, W., Burns, J. A. & Bilski, K. The astronomical theory of climate change on Mars. Icarus 44, 552–607 (1980)

    ADS  Article  Google Scholar 

  2. Jakosky, B. M. & Carr, M. H. Possible precipitation of ice at low latitudes of Mars during periods of high obliquity. Nature 315, 559–561 (1985)

    ADS  CAS  Article  Google Scholar 

  3. Mellon, M. T. & Jakosky, B. M. The distribution and behavior of Martian ground ice during past and present epochs. J. Geophys. Res. 100, 11781–11799 (1995)

    ADS  Article  Google Scholar 

  4. Mischna, M. A., Richardson, M. I., Wilson, R. J. & McCleese, D. J. On the orbital forcing of martian water and CO2 cycles: A general circulation model study with simplified volatile schemes. J. Geophys. Res. E 108 5062 doi: 10.1029/2003JE002051 (2003)

    ADS  Article  Google Scholar 

  5. Levrard, B., Forget, F., Montmessian, F. & Laskar, J. Recent ice-rich deposits formed at high latitudes on Mars by sublimation of unstable equatorial ice during low obliquity. Nature 431, 1072–1075 (2004)

    ADS  CAS  Article  Google Scholar 

  6. Forget, F., Haberle, R. M., Montmessin, F., Levrard, B. & Head, J. W. Formation of glaciers on Mars by atmospheric precipitation at high obliquity. Science 311, 368–371 (2006)

    ADS  CAS  Article  Google Scholar 

  7. Boynton, W. V. et al. Distribution of hydrogen in the near-surface of Mars: evidence for subsurface ice deposits. Science 297, 81–85 (2002)

    ADS  CAS  Article  Google Scholar 

  8. Feldman, W. C. et al. Global distribution of neutrons from Mars: results from Mars Odyssey. Science 297, 75–78 (2002)

    ADS  CAS  Article  Google Scholar 

  9. Mitrofanov, I. G. et al. Maps of subsurface hydrogen from the high-energy neutron detector, Mars Odyssey. Science 297, 78–81 (2002)

    ADS  CAS  Article  Google Scholar 

  10. Mellon, M. T., Feldman, W. C. & Prettyman, T. H. The presence and stability of ground ice in the southern hemisphere of Mars. Icarus 169, 324–340 (2004)

    ADS  CAS  Article  Google Scholar 

  11. Schorghofer, N. & Aharonson, O. Stability and exchange of subsurface ice on Mars. J. Geophys. Res. 110 E05003 doi: 10.1029/2004JE002350 (2005)

    ADS  Google Scholar 

  12. Mellon, M. T. & Jakosky, B. M. Geographic variations in the thermal and diffusive stability of ground ice on Mars. J. Geophys. Res. 98, 3345–3364 (1993)

    ADS  Article  Google Scholar 

  13. Hudson, T. L. et al. Water vapor diffusion in Mars subsurface environments. J. Geophys. Res. 112 E05016 doi: 10.1029/2006JE002815 (2007)

    ADS  Google Scholar 

  14. Leighton, R. B. & Murray, B. C. Behavior of carbon dioxide and other volatiles on Mars. Science 153, 136–144 (1966)

    ADS  CAS  Article  Google Scholar 

  15. Prettyman, T. H. et al. Composition and structure of the Martian surface at high southern latitudes from neutron spectroscopy. J. Geophys. Res. 109 E05001 doi: 10.1029/2003JE002139 (2004)

    ADS  Article  Google Scholar 

  16. Mellon, M. T., Jakosky, B. M. & Postawko, S. E. The persistence of equatorial ground ice on Mars. J. Geophys. Res. 102, 19357–19369 (1997)

    ADS  Article  Google Scholar 

  17. Laskar, J. et al. Long term evolution and chaotic diffusion of the insolation quantities of Mars. Icarus 170, 343–364 (2004)

    ADS  Article  Google Scholar 

  18. Ward, W. R. Climatic variations on Mars I. Astronomical theory of insolation. J. Geophys. Res. 79, 3375–3386 (1974)

    ADS  Article  Google Scholar 

  19. Litvak, M. L. et al. Comparison between polar regions of Mars from HEND/Odyssey data. Icarus 180, 23–37 (2006)

    ADS  Article  Google Scholar 

  20. Feldman, W. C. et al. The global distribution of near-surface hydrogen on Mars. J. Geophys. Res. 109 E09006 doi: 10.1029/2003JE002160 (2004)

    ADS  Google Scholar 

  21. Feldman, W. C. et al. Vertical distribution of hydrogen at high northern latitudes on Mars: The Mars Odyssey Neutron Spectrometer. Geophys. Res. Lett. 34 L05201 doi: 10.1029/2006GL028936 (2007)

    ADS  Article  Google Scholar 

  22. Mustard, J. F., Cooper, C. D. & Rifkin, M. K. Evidence for recent climate change on Mars from the identification of youthful near-surface ground ice. Nature 412, 411–414 (2001)

    ADS  CAS  Article  Google Scholar 

  23. Head, J. W., Mustard, J. F., Kreslavsky, M. A., Milliken, R. E. & Marchant, D. R. Recent ice ages on Mars. Nature 426, 797–802 (2003)

    ADS  CAS  Article  Google Scholar 

  24. Laskar, J., Levrard, B. & Mustard, J. F. Orbital forcing of the martian polar layered deposits. Nature 419, 375–377 (2002)

    ADS  CAS  Article  Google Scholar 

  25. Schorghofer, N. Theory of ground ice stability in sublimation environments. Phys. Rev. E 75, 041201 (2007)

    ADS  Article  Google Scholar 

Download references


I thank O. Aharonson and B. Jakosky for discussions and E. Pilger for computing help. This material is based upon work supported by the NASA Astrobiology Institute.

Author information

Authors and Affiliations


Corresponding author

Correspondence to Norbert Schorghofer.

Ethics declarations

Competing interests

Reprints and permissions information is available at The author declares no competing financial interests.

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Schorghofer, N. Dynamics of ice ages on Mars. Nature 449, 192–194 (2007).

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI:

Further reading


By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.


Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing