Rafael L. Bras

2007 Robert E. Horton Medal Winner

University of California, Irvine

Rafael L. Bras was awarded the 2007 Robert E. Horton Medal during a special presentation at the AGU Fall Meeting Honors Ceremony, held 17 December 2008 in San Francisco, Calif. The medal is for “outstanding contributions to hydrology.”


I am extremely happy to introduce Rafael L. Bras, winner of the 2007 AGU Robert E. Horton Medal. There is no doubt in any hydrologist’s mind that Bras is superbly qualified for this award. His combination of breadth and depth in the coverage of multiple fields in the hydrologic sciences has earned him a place among the most distinguished hydrologists of the past half century.

Rafael is dean of engineering and distinguished professor of civil and environmental engineering at University of California, Irvine. Until recently he was the Edward Abdun-Nur Professor of Civil and Environmental Engineering at Massachusetts Institute of Technology (MIT), where he also had a joint appointment in the Department of Earth, Atmospheric, and Planetary Sciences. His leadership in the hydrologic sciences has been superb. He is the author of two textbooks widely used throughout the world and of over 160 papers in major journals with many more in books and conference proceedings. This is indeed an outstanding scientific production; nevertheless it wouldn’t mean much if it were not for the truly magnificent quality of Rafael’s contributions. It is marvelous how he covers such a wide range of topics in water science and technology with the impressive depth of knowledge and creative thinking that he displays in all of his work. I had the privilege of being his Ph.D. advisor and remember very well that my recommendation when I left MIT, to the then department head, Peter S. Eagleson, was to bring Rafael back from Puerto Rico to take my position. I assured Pete on how much the Institute would win with the trade! I am proud that I was indeed correct in my prediction and that Rafael has become a world leader of the field and a source of inspiration and pride for MIT, the University of California at Irvine, and his friends.

Without going into full details about his multiple and outstanding research contributions, I want to mention that Rafael has made pathbreaking research in hydrologic network design, urban storm water management, forecasting of hydrologic series, rainfall modeling, optimal operation of water systems, irrigation control, soil-atmosphere interaction, ecohydrology, and the fractal structure of drainage networks. In all of these areas, Rafael has left a permanent impact throughout research that is uniformly excellent, characterized in all cases by a wonderful choice of problems, and full of creative and imaginative ideas.

Rafael’s excellence in research has brought him numerous distinctions nationally and internationally. In the United States he has received multiple awards from the American Society of Civil Engineers and the American Meteorological Society. He is also a member of the National Academy of Engineering and a recipient of the Clarke Prize, for outstanding achievement in water sciences and technology. The American Geophysical Union has distinguished him with the Hydrologic Sciences Award and the James B. Macelwane Medal. The number and quality of his students is also impressive. They are all over the world occupying leadership positions in academia, major corporations, and government organizations.

Even a full recital of Rafael’s unique achievements would not convey an appropriate description of what is most important in him: the qualities of his character, his love for his family, his honesty, and his genuine care for the advancement and equal treatment of all people. It has been my great privilege to have been his friend for 35 years as well as to share in the love of his wonderful family, Pat, Rafael E., and Alejandro, who occupy a very special place in the heart of my own family.

—IGNACIO RODRIGUEZ-ITURBE, Princeton University, Princeton, N. J.


Some years ago I gave a talk entitled “Everything I learned wrong at MIT.” This title was meant to be a tongue-in-cheek provocation, but the content was serious. Hydrology has evolved so much that nothing I do now I learned at that time. It could not have been a better time for a hydrologist; I have had the license to explore with the necessary luxury of being able to be wrong once in a while. That the land hydrologic cycle could be inherently linked and important to the atmosphere was considered ridiculous until fairly recently. Interpreting nature as a product of both chance and necessity and discovering the physical basis of apparently random behavior opened the door to a whole new set of methodologies. We started doing optimal estimation and data assimilation 30 years ago, and now it is operational in atmospheric sciences and hydrology. Reinterpreting the observations of Horton about the organization of river basins as fractals was the breakthrough needed to inspire a few of us to seek a mechanistic explanation of why such organization occurs, and to explain and predict how the landscape evolves in a tightly choreographed dance with water flow, sediment transport, climate, and vegetation. The term ecohydrology did not exist when I was a student. But now we have come to the realization that all hydrologic processes are mediated, if not controlled, by the biosphere. I could go on, but suffice it to say that I have lived a true revolution. Back in 1987 Pete Eagleson and I wrote a piece for Eos entitled “Hydrology: The forgotten science.” Well, it is not forgotten anymore; it is established and valued. I have been honored to play a small role in that revolution, and I have loved every minute of it.

No one succeeds in life alone, and in my case I have been truly fortunate to have the proverbial village behind me. My life is full of opportunities taken, opportunities that were created and introduced by a very large number of people. Twenty-two other individuals received this medal before me. These are the people who built modern hydrologic sciences. To have known many of them and be considered part of this august group is humbling. But I have been further blessed by counting some of them and others among my mentors and good friends. I have to mention Ignacio Rodriguez-Iturbe, Peter Eagleson, and the late Donald Harleman. Without their advice and care I simply would not be here.

My wife, Pat, and our sons, Rafael E. and Alejandro, are always my fellow adventurers. Thank you for never letting me forget the important things of life.

All professors know that their success is due to their students. I have had over 50 students in the MIT “Bras Group.” To them I dedicate this medal; they are the best, and also the most fun. I am looking forward to having another 50 students at my new academic home, the University of California, Irvine. To all past and future students, please remember that many times it is better ultimately to be proven wrong than to be boring. Be bold and carry on with the revolution.

—RAFAEL L. BRAS, University of California, Irvine