Jasper A. Vrugt

2010 James B. Macelwane Medal Winner

University of California

David B. Lobell, Rosalind E. Rickaby, and Jasper A. Vrugt were awarded the 2010 James B. Macelwane Medal at the AGU Fall Meeting Honors Ceremony, held on 15 December 2010 in San Francisco, Calif. The medal is for “significant contributions to the geophysical sciences by an outstanding young scientist.”


I would like to open my citation for Jasper Vrugt with the simple phrase, “Hard work and persistence pay off.” The reason for my starting with this is that I recall back in early 2000, when Jasper came to the University of Arizona as a visiting graduate student from the University of Amsterdam to work with me and my colleague Hoshin Gupta. We found him to be a nonstop workaholic with tons of ideas matched by boundless energy to pursue them. I vividly recall one Christmas Eve, having to go to my office at the University of Arizona, when I noticed a light shining through a crack in an office door. My curiosity led me to discover that there was actually someone in the room working on Christmas Eve, and it happened to be Jasper. In response to my question, “What are you doing here on Christmas Eve, Jasper?” I got the reply, “I am trying to finish a few more simulation runs.” The conversation ended by Jasper saying, “Becoming a famous hydrologist does not come without time and effort.”

Almost 10 years later, I am pleased to be the citationist for Jasper Vrugt as one of the 2010 AGU James B. Macelwane medalists.

Jasper’s contributions can best be characterized in terms of his unique ability of developing novel systems and modeling approaches to address a wide range of Earth and environmental science problems including a variety of issues related to hydrology. Vrugt’s scholarly accomplishment is best reflected in his impressive publication track record in the best journals in a number of disciplines, among them Proceedings of the National Academy of Sciences.

While working toward his M.S. degree at the University of Amsterdam, Netherlands, Jasper tackled a classic experimental method in soil physics: laboratory outflow experiments for assessing soil hydraulic properties. He took a quite different approach to inverse modeling and used numerical experiments to explain why many published studies in the hydrologic literature demonstrated the nonuniqueness of soil hydraulic properties.

Jasper’s work on combining the principles of evolutionary search with the Markov chain Monte Carlo simulation have provided important ways to appropriately and efficiently treat model parameter uncertainty.

Another area of notable contribution is Jasper’s new concept of self-adaptive multimethod optimization. Theoreticians and computer scientists have been trying for years to find a single optimization algorithm that is always most efficient for a large range of parameter estimation problems. Jasper’s creative idea of running multiple search algorithms concurrently that learn from each other through information exchange using a common population of points is perhaps the most elegant way of exploiting the strengths of individual search methods to address the “no free lunch theorem.” Jasper’s body of work on parameter estimation and uncertainty estimation has already led to profound advances in hydrologic modeling and laboratory and field methods.

To close my citation, I congratulate not only Jasper for his remarkable accomplishments as a young scientist but also AGU for recognizing his talent.

—SOROOSH SOROOSHIAN, University of California, Irvine


I will never forget my excitement on 17 October 1998 as I boarded an Iceland­air Boeing jet at Schiphol Airport, Netherlands, and headed off for the beginnings of an unimagined future. I had no immediate thoughts of where this journey would ultimately take me. After 10 years of traveling and about half a million air miles, I am excited to receive this prestigious medal and humbled to have my name added to an amazing list of previous winners who have helped shape the Earth sciences. I share this recognition with my family, mentors, friends, students, and colleagues. They exude enthusiasm for my work and research, and this medal is just as much a reflection of their hard work, support, and dedication as it is mine.

The boarding of my plane began a long odyssey of personal, cultural, and scientific discovery in the realm of environmental systems modeling, parameter estimation, Bayesian statistics, nonlinear optimization, and high performance computing. During my Ph.D. appointment in Amsterdam, I morphed from a Dutchman to a man of the world, and I was eventually able to parlay an inexperienced researcher and writer into the beginnings of a scientist. My Oppenheimer Fellowship at Los Alamos National Laboratory provided an unprecedented research opportunity and helped me to embrace a career outside Europe, far away from the Netherlands and my childhood friends and family. Currently, my position at University of California, Irvine offers me a challenging and versatile academic life with outstanding faculty and students, all enjoyed under sunny southern California skies.

I am indebted to my nominator, Soroosh Sorooshian, for his unselfishness, his relentless support of young scientists, and being a worldwide ambassador of hydrology; Willem Bouten for his critical attitude, inspiration, and opportunities created; Hoshin Gupta for sharing his brilliant mind; Cees Diks and Cajo ter Braak for their creative ideas; Bruce Robinson for a license to explore; and Jan Hopmans for teaching me how to write and for fostering my roots in Davis. Without your advice and support I simply would not be here.

In closing, I would like to thank AGU and the Macelwane Committee for this award and the platform of scientific discussion and publication the organization provides. I hope that my students and I can continue to produce meaningful contributions.

My success is due to my parents. Their unconditional love and never ending support have been instrumental at all stages of my life. I therefore dedicate this medal to them. Mom, Dad, I’m happy that you are here with my brother and his family to celebrate this moment with me in San Francisco. We have been through it all, and you love me just the same. You are the very best this world has to offer.

—JASPER A. VRUGT, University of California, Irvine