Mitchell Receives 2013 Ronald Greeley Early Career Award in Planetary Science

Jonathan L. Mitchell received the 2013 Ronald Greeley Early Career Award in Planetary Science at the 2013 AGU Fall Meeting, held 9–13 December in San Francisco, Calif. The award recognizes significant early-career contributions to planetary science.


mitchell_jonathan-lThe Greeley Early Career Award is named for pioneering planetary scientist Ronald Greeley. Ron was involved in nearly every major planetary mission from the 1970s until his death and was extraordinarily active in service to the planetary science community. Ron’s greatest legacies, however, are those he mentored through the decades, and it is young scientists whose work and promise we seek to recognize. This year’s Greeley award winner is Jonathan L. Mitchell, an assistant professor at the University of California, Los Angeles (UCLA). Jonathan received his Ph.D. from the University of Chicago, and after a postdoc at the Institute for Advanced Studies in Princeton, he joined the UCLA faculty, where he holds a joint appointment in Earth and space sciences and in atmospheric sciences.

Jonathan is one of the few planetary scientists, young or old, who is also a recognized expert in geophysical fluid dynamics and the fundamental theory of atmospheric circulation as it has been developed in the terrestrial community over the past half century. This places Jonathan in a rather unique position to understand the dynamical processes occurring in planetary atmospheres. Jonathan has already made major contributions to our understanding of Titan’s atmosphere, the existence of equatorial superrotation in planetary atmospheres generally, atmospheric thermodynamics, and the atmospheric and interior dynamics of hot giant exoplanets.

As an example, Jonathan’s detailed three-dimensional circulation models for Titan have explained how equatorial and midlatitude cloud systems can lead to precipitation that greatly exceeds the time-averaged precipitation rates, up to perhaps several centimeters of liquid methane rain in individual events. Such rare but intense events must cause significant fluvial erosion, so Jonathan’s models help to explain the existence of widespread fluvial erosion features on Titan’s surface at low latitudes, which are otherwise relatively dry and lake free.

Jonathan’s adaptation of Earth-based knowledge to solve planetary problems and his judicious comparisons of physical mechanisms on different planets are what Ron Greeley would have termed comparative planetology and are very much in Ron’s style, as is Jonathan’s mentoring of his growing research group.

Congratulations to Jonathan L. Mitchell, the 2013 recipient of the Ronald Greeley Early Career Award in Planetary Science.

—WILLIAM B. MCKINNON, Washington University, St. Louis, Mo.


I am honored to receive this award in memory of Ron Greeley. Although I did not have the opportunity to know him, I had the pleasure of getting to know his wife, Cynthia, at a luncheon prior to the special awards session at the AGU Fall Meeting. Cynthia is an intelligent and elegant southern woman with a confident gaze. She spoke fondly of Ron and of her sincere respect for his work ethic and dedication to planetary science. What most impressed me, though, was the respect Ron showed to her and the kids by always “giving them the evenings”; no matter how busy things got, Ron always kept his evenings open for Cynthia. This clearly meant the world to her. As a family man, I can only hope that my wife and kids will speak so kindly of me many years from now. I would like to dedicate this award to them in gratitude for their seemingly unconditional love and support.

I would also like to take this opportunity to thank the individuals who have positively influenced my career. I owe nearly all my inspiration to the Cassini team; many thanks to you all. My thanks to Ray Pierrehumbert for taking a chance on a disillusioned cosmologist when he agreed to be my thesis advisor. Working with Ray reminded me that science should be (and is) fun. Thanks also to Geoff Vallis and Peter Goldreich for their mentoring during my postdoc years and for their continued advocacy in my early career. Thanks to my anonymous senior colleagues who nominated me and to the selection committee for this great honor. And, finally, thanks to my parents who always encouraged me that I could do whatever I set my mind to.

—JONATHAN L. MITCHELL, University of California, Los Angeles