Tim Michaels
Tim Michaels

Research Scientist

Disciplines: Planetary Atmospheres

Degree/Major: M.S., Meteorology, 2002, San Jose State University

Curriculum vitae: CV_TIM_Michaels_Xp_Oct2014.pdf


Tim Michaels' passion is to explore and understand the important (but largely unseen and invisible) motions and interactions that occur between the atmospheres and surfaces of many worlds.  How can someone explore what is largely invisible?  Tim programs and uses computer physics simulations ("models") to fill in many of the gaps between any measurements and clues that do exist -- much like the way computer models and weather measurements are used together on Earth to forecast the weather a few days in advance for your home town.

Atmosphere-surface interactions on Mars and Pluto are currently his main areas of research, but Earth, Venus, Titan, Triton, and exoplanets are also of great interest to him.  Tim Michaels makes use of a diverse range of atmospheric modeling, from the global scale all the way down to the local scale (to study dust devils and sand dunes, for example).

Substances that change phase (like water melting or freezing) are an important part of his work, such as the CO2-ice and H2O-ice clouds and seasonal polar caps on Mars, and Pluto's nitrogen and methane surface ice and atmosphere.

With the help of computer processing and graphics software, Tim renders huge amounts of high-resolution atmospheric simulation output into forms suitable to compare to measurements (from orbiting or landed spacecraft, telescopes, and in the case of Earth, from people, weather stations, and balloons).  He finds it fascinating and humbling to simply watch on the computer screen as a vast "ocean" of air and/or clouds surges and swirls, sometimes violently, across the landscape -- a brief insight into what slowly, but surely, alters the surface of that distant world forever.


Stillman, D.E., T.I. Michaels, R.E. Grimm (2014), New observations of martian southern mid-latitude recurring slope lineae (RSL) imply formation by freshwater subsurface flows. Icarus, 233, 328-341, doi:10.1016/j.icarus.2014.01.017.

Fenton, L.K., T.I. Michaels, R.A. Beyer (2014), Inverse maximum gross bedform-normal transport 1: How to determine a dune-constructing wind regime using only imagery. Icarus, 230, 5-14, doi:10.1016/j.icarus.2013.04.001.

Fenton, L.K., T.I. Michaels, M. Chojnacki, R.A. Beyer (2014), Inverse maximum gross bedform-normal transport 2: Application to a dune field in Ganges Chasma, Mars and comparison with HiRISE repeat imagery and MRAMS. Icarus, 230, 47-63, doi:10.1016/j.icarus.2013.07.009.

Fenton, L.K., R.K. Hayward, B.H.N. Horgan, D.M. Rubin, T.N. Titus, M.A. Bishop, D.M. Burr, M. Chojnacki, C.L. Dinwiddie, L. Kerber, A. Le Gall, T.I. Michaels, L.D.V. Neakrase, C.E. Newman, D. Tirsch, H. Yizhaq, J.R. Zimbelman (2013), Summary of the Third International Planetary Dunes Workshop: Remote Sensing and Image Analysis of Planetary Dunes, Flagstaff, Arizona, USA, June 12-15, 2012. Aeolian Research, 8, 29-38, doi:10.1016/j.aeolia.2012.10.006.

Zalucha, A.M., T.I. Michaels, N. Madhusudhan (2013), An investigation of a super-Earth exoplanet with a greenhouse-gas atmosphere using a general circulation model. Icarus, 226, 1743-1761, doi:10.1016/j.icarus.2012.12.019.

Zalucha, A.M., and T.I. Michaels (2013), A 3D general circulation model for Pluto and Triton with fixed volatile abundance and simplified surface forcing. Icarus, 223, 819-831, doi:10.1016/j.icarus.2013.01.026.

Balme, M.R., A. Pathare, S.M. Metzger, M.C. Towner, S.R. Lewis, A. Spiga, L.K. Fenton, N.O. Renno, H.M. Elliott, F.A. Saca, T.I. Michaels, P. Russell, J. Verdasca (2012), Field measurements of horizontal forward motion velocities of terrestrial dust devils: Towards a proxy for ambient winds on Mars and Earth. Icarus, 221, 632-645, doi:10.1016/j.icarus.2012.08.021.

Kok, J.F., E.J.R. Parteli, T.I. Michaels, D.B. Karam (2012), The physics of wind-blown sand and dust. Reports on Progress in Physics, 75, 106901, doi:10.1088/0034-4885/75/10/106901.

Silvestro, S., L.K. Fenton, T.I. Michaels, A. Valdez, G.G. Ori (2012), Interpretation of the complex dune morphology on Mars: dune activity, modelling and a terrestrial analogue. Earth Surf. Process. Landforms. doi: 10.1002/esp.3286

Kite, E.S., S.C.R. Rafkin, T.I. Michaels, W.E. Dietrich, M. Manga (2011), Chaos terrain, storms, and past climate on Mars . J. of Geophys. Res., 116 (E10002).

Kite, E.S., T.I. Michaels, S.C.R. Rafkin, M. Manga, W.E. Dietrich (2011), Localized precipitation and runoff on Mars . J. of Geophys. Res., 116 (E07002).

Chojnacki, M., D.M. Burr, J.E. Moersch, T.I. Michaels (2011), Orbital observations of contemporary dune activity in Endeavor crater, Meridiani Planum, Mars. J. of Geophys. Res., 116 (E00F19).

Fenton, L.K., M.A. Bishop, M.C. Bourke, C.S. Bristow, R.K. Hayward, B.H. Horgan, N. Lancaster, T.I. Michaels, D. Tirsch, T.N. Titus, et al. (2010), Summary of the Second International Planetary Dunes Workshop: Planetary Analogs — Integrating Models, Remote Sensing, and Field Data, Alamosa, Colorado, USA, May 18-21, 2010. Aeolian Research, 2, 173-178.

Fenton, L.K., and T.I. Michaels (2010), Characterizing the sensitivity of daytime turbulent activity on Mars with the MRAMS LES: Early results, Mars, 5, 159-171, doi:10.1555/mars.2010.0007.

Bridges, N.T., M.E. Banks, R.A. Beyer, F.C. Chuang, E.Z. Noe Dobrea, K.E. Herkenhoff, L.P. Keszthelyi, K.E. Fishbaugh, A.S. McEwen, T.I. Michaels, et al. (2010), Aeolian bedforms, yardangs, and indurated surfaces in the Tharsis Montes as seen by the HiRISE Camera: Evidence for dust aggregates . Icarus, 205, 165-182.

Hayward, R.K., T.N. Titus, T.I. Michaels, L.K. Fenton, A. Colaprete, P.R. Christensen (2009), Aeolian dunes as ground truth for atmospheric modeling on Mars . J. of Geophys. Res., 114 (E11012).

Clancy, R.T., M.J. Wolff, B.A. Cantor, M.C. Malin, T.I. Michaels (2009), Valles Marineris cloud trails. J. of Geophys. Res., 114 (E11002).

Titus, T.N., T.I. Michaels (2009), Determining Priorities for Future Mars Polar Research . Eos, Transactions American Geophysical Union, 90, October, 351.

Michaels, T.I., and S.C.R. Rafkin (2008), Meteorological predictions for candidate 2007 Phoenix Mars Lander sites using the Mars Regional Atmospheric Modeling System (MRAMS), J. Geophys. Res., 113, E00A07, doi:10.1029/2007JE003013.

Tamppari, L.K., J. Barnes, E. Bonfiglio, B. Cantor, A.J. Friedson, A. Ghosh, M.R. Grover, D. Kass, T.Z. Martin, M. Mellon, T.I. Michaels, et al. (2008), Expected atmospheric environment for the Phoenix landing season and location. J. of Geophys. Res., 113 (E00A20).

Greeley, R., P.L. Whelley, L.D.V. Neakrase, R.E. Arvidson, N.T. Bridges, N.A. Cabrol, P.R. Christensen, Kaichang Di, D.J. Foley, M.P. Golombek, T.I. Michaels, et al. (2008), Columbia Hills, Mars: Aeolian features seen from the ground and orbit . J. of Geophys. Res., 113 (E06S06).

Sta. Maria, M.R.V., S.C.R. Rafkin, T.I. Michaels (2006), Numerical simulation of atmospheric bore waves on Mars. Icarus, 185, 383-394.

Michaels, T.I., A. Colaprete, and S.C.R. Rafkin (2006), Significant vertical water transport by mountain-induced circulations on Mars. Geophys. Res. Lett., 33, doi:10.1029/2006GL026562.

Michaels, T.I. (2006), Numerical modeling of Mars dust devils: Albedo track generation. Geophys. Res. Lett., 33, doi:10.1029/2006GL026268.

Greeley, R., R.E. Arvidson, P.W. Barlett, D. Blaney, N.A. Cabrol, P.R. Christensen, R.L. Fergason, M.P. Golombek, G.A. Landis, M.T. Lemmon, T.I. Michaels, et al. (2006), Gusev crater: Wind-related features and processes observed by the Mars Exploration Rover Spirit . J. of Geophys. Res., 111 (E02S09).

Michaels, T.I., and S.C.R. Rafkin (2004), Large-eddy simulation of atmospheric convection on Mars. Q. J. R. Meteorol. Soc., 130(599), 1251-1274.

Rafkin, S.C.R., T.I. Michaels, R. Haberle (2004) , Meteorological predictions for the Beagle 2 mission to Mars. Geophys. Res. Lett., 31 (L01703).

Kass, D.M., J.T. Schofield, T.I. Michaels, S.C.R. Rafkin, M.I. Richardson, A.D. Toigo (2003), Analysis of atmospheric mesoscale models for entry, descent, and landing . J. of Geophys. Res., 108 (E12), doi:10.1029/2003JE002065.

Rafkin, S.C.R., T.I. Michaels (2003), Meteorological predictions for 2003 Mars Exploration Rover high-priority landing sites . J. of Geophys. Res., 108 (E12), doi:10.1029/2002JE002027.

Greeley, R., R.O. Kuzmin, S.C.R. Rafkin, T.I. Michaels, R. Haberle (2003), Wind-related features in Gusev crater, Mars . J. of Geophys. Res., 108 (E12), doi:10.1029/2002JE002006.

Rafkin, S.C.R., and T.I. Michaels (2003), Meteorological predictions for 2003 Mars Exploration Rover high-priority landing sites. J. Geophys. Res., 108, doi:10.1029/2002JE002027.

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

Rafkin, S.C.R., R. Haberle, and T.I. Michaels (2001), The Mars Regional Atmospheric Modeling System: Model Description and Sel