Jean Jouzel

2003 Roger Revelle Medal Winner

Gif Sur Yvette, France

Jean Jouzel received the Roger Revelle Medal at the EGS AGU EUG Joint Assembly held in Nice, France, 6-11 April 2003. The medal is given for outstanding contributions toward an understanding of the Earth’s atmospheric processes, including its dynamics, chemistry, and radiation; the roles of atmosphere, atmosphere ocean coupling; or atmosphere land coupling in determining the climate, biogeochemical cycles, or other key elements of the integrated climate system.


“It is a real pleasure and an honor for me to cite Dr. Jean Jouzel for the Roger Revelle Medal of the American Geophysical Union. Polar ice core records have revolutionized our view of the Earth’s climate system, and this depends to a significant degree on his accomplishments. Jean Jouzel is truly a giant in the arena of global environmental scientific research. In short, he did pioneering and fundamental work in the field of geochemistry as applied to glaciology and climatology. His work is a perfect realization of the promise that paleoclimate research will lead to a better understanding of current and future climate.

“After obtaining a degree in chemistry, Jean Jouzel became involved in isotope geochemistry during his Ph.D. thesis, focused on the growth of large hailstones. Such fundamental studies made him familiar with the various aspects of isotopic fractionation that affect water molecules during their atmospheric cycle. Another early contribution was the development in collaboration with Liliane Merlivat of simple models accounting for the equilibrium and kinetic effects during evaporation over the sea and the condensation of snow crystals.

“Jean Jouzel started ice core research in the mid 1970s in close collaboration with Claude Lorius and his group in Grenoble. In particular, he became fully involved in the Vostok ice core program, conducted in the framework of a collaboration between French, Russian, and U.S. scientists. That wonderful Vostok paleoclimatic record is the current gold standard for long paleoclimatic records of the atmosphere.

“Far from being just a producer of important data, Jean Jouzel has also been a leader in efforts to understand the meaning of the isotopic ratios of water. In collaboration with Sylvie Joussaume and Randy Koster, he initiated the first attempts to integrate stable isotopes into general circulation models, thereby providing a much stronger physical underpinning of the proxy reconstructions and the characteristics of the glacial atmosphere.

“Jean Jouzel has promoted these complementary modeling strategies essentially for improving the use of water isotopes as tools to reconstruct climate changes from ice cores. It is exceedingly valuable to be able to interpret ice core isotopic records not just as wiggly lines but as fundamental paleoclimatic indicators.

“Jouzel’s impressive list of publications emphasizes not only the scientific content of his work, but also the energy he has invested in relating the results to the wider scientific community. Jean Jouzel has established close links with paleoceanographers in order to make the best possible use of ice core records to study climatic changes at all time scales.

“Added to this long list of accomplishments, Jean Jouzel has advanced science through service in numerous important ways. As a lead author in IPCC reports, he has helped unite and guide the world community researching climate change. More recently, Jean Jouzel has successfully launched the European Program for Ice Coring in Antarctica (the EPICA project).

“In addition to his scientific prowess, his open and congenial manner fully represents the tradition established by Roger Revelle, which is highlighted by this prestigious medal for ‘contributions toward an understanding of the Earth’s atmospheric processes, including its dynamics, chemistry, and radiation; and toward the role of the atmosphere, atmosphere ocean coupling, or atmosphere land coupling in determining the climate, biogeochemical cycles, or other key elements of the climate system.’”

—EDOUARD BARD, Université Aix Marseille, France


“I am very honored to be awarded the AGU Roger Revelle Medal. I would like to thank deeply all those who have helped to make this happen and first to express my gratitude to my long time friend Edouard Bard.

“I met Roger Revelle only once, on the occasion of a seminar he gave at NASA/GISS NewYork in the 1980s, and I was very impressed by his scientific stature. At the time, I was myself a visiting scientist at GISS as a guest of two former recipients of the Roger Revelle Medal, Jim Hansen and Wally Broecker, both of whom were very supportive of our efforts aiming to incorporate water isotopes into the GISS general circulation model. This period was one of the most exciting of my scientific career. Not only did I get to play with models, thanks to Jim, Wally, and others, but I was also involved with French and Russian colleagues in the Vostok adventure, which was providing crucial evidence of a strong interaction between climate and greenhouse gases.

“A few years later, I was in central Greenland as a member of the European GRIP deep drilling project, which, along with its sister U.S. project, GISP2, has played a key role in deciphering the story of rapid climatic changes. I realize now how lucky I was to be involved in both the far north and south.

“What I appreciate most about ice core research is the strong spirit of collaboration among teams interested in looking at different properties and records extracted from these marvelous archives of our climate and environment. This is true at the French level with the close ‘historical’ links among teams from Grenoble, Saclay, and Orsay, which all benefit from the logistic support of the Brest Polar Institute. Collaboration on international projects is indeed the general rule in polar research: Russia, France, and the United States at Vostok, European projects in Greenland (GRIP) and now in Antarctica (EPICA), an international project at North GRIP. But this list of very stimulating and friendly collaborations also includes scientists from Australia, Canada, China, Estonia, South America, and more recently, Japan. In recognition of the profound collaboration that goes into ice core research, I would like to associate with this Roger Revelle Medal all the colleagues with whom it has been an immense pleasure to work.

“I have long been convinced—and here I have the opportunity to fully acknowledge the contribution of Claude Lorius, who introduced me to ice core research 30 years ago, and of Hans Oeschger, a former Revelle medalist—that looking at the past is a key to understanding the future. This applies not only to ice cores but also to oceanic and continental archives. Indeed, I feel very close to paleoceanographers and continentalists, as well as to paleoclimate modelers. Thanks to a common effort, the relevance of paleoclimate research to future climate change is now fully recognized; this is one facet of our field of which I am very proud.

“I would like to acknowledge all my colleagues and close collaborators, scientists, technicians, and Ph.D. students for their invaluable contribution to ice core research; and research institutions and funding agencies, in particular the CEA and CNRS, the European communities, and the European Science Foundation, for their support.’”

—JEAN JOUZEL, CEA/SACLAY/DSM, Gif Sur Yvette, France