Thomas Rossby

2009 Maurice Ewing Medal Winner

Graduate School of Oceanography, University of Rhode Island, Narragansett

H. Thomas Rossby was awarded the 2009 Maurice Ewing Medal at the AGU Fall Meeting Honors Ceremony, held on 16 December 2009 in San Francisco, Calif. The medal is for “significant original contributions to the scientific understanding of the processes in the ocean; for the advancement of oceanographic engineering, technology, and instrumentation; or outstanding service to marine science.”


Thomas Rossby pursues oceanography with unparalleled technical inventiveness, dogged persistence in fieldwork, and scientific insight. These were also qualities of Maurice Ewing, for whom this medal is named. Rossby’s work has given oceanography drifting and profiling devices, whose implementation in the field has returned a wealth of discoveries. Following the original Swallow float, he and Douglas Webb created the SOFAR (sound fixing and ranging) float, using long-range acoustics, which drifts with deep currents. This provided the first densely resolved, animated picture of the chaotic flow of the deep ocean, in the Mid-Ocean Dynamics Experiment of 1973. It was fitting that these new data revealed for the first time in the oceans the westward propagation of deep current features such as Rossby waves, which Tom’s illustrious father Carl-Gustav had developed analytically and observationally for the atmospheric circulation. Rossby waves are at the heart of the ocean’s general circulation, shaping and intensifying it into jets like the Gulf Stream. The SOFAR float sparked the invention of a long line of Lagrangian instruments, among them the isopycnal RAFOS floats of today. Lagrangian instruments, moving with the water, tell us about the restless movement of chemical tracers and biological communities in the sea. The Argo float developed by Russ Davis is in many ways a descendent of Tom’s drifting SOFAR floats. Argo floats are now a key contribution to global synoptic climate observations.

Rossby’s instruments are designed to confront some of the most difficult problems in oceanography. For example, RAFOS floats and inverted echo sounders have shown us the inner structure of the Gulf Stream. He is dedicated to high-quality observations, extensive in space and time. Instrumenting the freighter Oleander on a regular run between New York and Bermuda in 1992, he has collected high-quality acoustic Doppler velocity sections of the Gulf Stream ever since. Tom refers to “merchant vessels operating as ocean-level orbiting satellites.” Other such vessels are plying the subpolar Atlantic while his floats deep beneath the surface trace out the chaotic pathways of the ocean’s overturning circulation. These observations contribute much to our understanding of the complex and variable ocean contribution to global climate.

Tom received his Ph.D. from the Massachusetts Institute of Technology (MIT) in 1966 and worked at MIT, Woods Hole Oceanographic Institution (WHOI), and Yale before joining the University of Rhode Island (URI), which provided him with the facilities for access to the sea. He has had a spectacular career at URI, where he has trained generations of graduate students. In spite of his monumental research contributions, he is extremely modest. He has received the Bigelow Gold Medal, the Suomi Award, and the Munk Award; is a fellow of several societies, one of which is AGU; and has been elected to the Norwegian Academy of Letters and Science and the American Academy of Arts and Sciences, as well as the National Academy of Engineering.

In conceiving new instruments and doing science with them, Rossby has been a role model for generations of students and younger colleagues. He is an avid and compassionate teacher and a warm and generous colleague.

—PETER B. RHINES, University of Washington, Seattle


Thank you, Peter, for your very generous remarks. It is a tremendous honor to receive the AGU Maurice Ewing Medal and a great pleasure to acknowledge my colleagues and students who partnered in this engineering and scientific journey. Without them I would not be here today.

Growing up in a natural science–oriented family in Sweden, I was given opportunities to climb mountains and glaciers as a child and study cloud convection as a teenager. In the spring, my father and I would search for wild orchids on the island of Gotland. Sadly, he passed away the summer I graduated from high school. Later, as my studies in applied physics at the Royal Institute of Technology were coming to an end, my mother, who had returned to the United States, George Veronis, and Joe Pedlosky all urged me to come to graduate school here. I was tired of the continual gruel of homework and wanted to get cracking on my career, but I agreed to give it a try. My wife-to-be was also keen to come to the United States.

While still in graduate school at MIT, Henry Stommel invited me to join him and Doug Webb in developing the SOFAR float technology to study ocean currents, a dream of his for many years. I was one of many who benefited from Hank’s wonderful way of enticing people into the field and letting them loose. Doug Webb was a fantastic mentor and collaborator, and I am indebted to him for instilling a sense of the possible—seeing solutions rather than problems. As head of the engineering group at WHOI, Doug played a major role in developing the broad suite of observational tools we have today in physical oceanography.

Some of the names that follow may not be familiar to you, but they played key roles in our activities over the years. First, I thank Martin Mork for insightful discussions in my formative years; he also encouraged me to develop YVETTE, an early generation Richardson number profiler. I thank Don Dorson for his work on the Pegasus velocity profiler; later, he and Jim Fontaine developed the RAFOS float. Jim also played a key role in developing the isopycnal float technology—we had a lot of fun at this.

The science side evolved in partnership with many wonderful students including Amy Bower, Henrik Søiland, Arthur Mariano, Steve Riser, and Paula Perez-Brunius. I must also mention past and present postdocs and colleagues Howard Freeland, Kuh Kim, Jim Price, Mary-Elena Carr, Olaf Boebel, Mark Prater, Dave Hebert, Randy Watts, and Godi Fischer. Honestly, this honor is every bit theirs as mine!

Finally, I must mention John Knauss, dean of the Graduate School of Oceanography (GSO), who invited me to join the GSO faculty at URI; it has been a fantastic place in which to work and grow. I thank my sponsors, the Office of Naval Research (ONR) and the U.S. National Science Foundation, for their support over the years. Again, I thank AGU and ONR for the Maurice Ewing Medal. This is a truly a tremendous honor!

—H. THOMAS ROSSBY, Graduate School of Oceanography, University of Rhode Island, Narragansett