Isaac M. Held was awarded the 2018 Roger Revelle Medal at the AGU Fall Meeting Honors Ceremony, held on 12 December 2018 in Washington, D. C. The medal is for “outstanding contributions in atmospheric sciences, atmosphere-ocean coupling, atmosphere-land coupling, biogeochemical cycles, climate or related aspects of the Earth system.”  

Isaac Held is recognized for his outstanding scientific contributions to the understanding of the dynamics of the Earth’s atmosphere and climate and for his pioneering insights into the structure of atmospheric circulation patterns and the interplay with the Earth’s hydrologic cycle. He is one of the deepest thinkers and a leading authority in climate dynamics, with his innovative science yielding novel perspectives on fundamental aspects of the atmospheric general circulation such as the width of the Hadley cell, relation between large-scale temperature gradients and eddy fluxes, and partitioning of heat transport in the tropics between the oceans and atmosphere. His achievements include development of a hierarchy of dynamical models of increasing complexity that have provided new pathways toward unraveling the complexity of the climate system.

Isaac’s insightful exposition of the spatial pattern of the response of the hydrological cycle to a warming of the climate, developed from basic thermodynamic and dynamical considerations, has established a firm quantitative basis. This has now become an essential component in our understanding of how, in a warming world, changes in the hydrological cycle and other related properties of the climate system, such as the global distribution of winds and storms, can be related to physical principles.

His exceptional scientific leadership at the National Oceanic and Atmospheric Administration’s (NOAA) Geophysical Fluid Dynamics Laboratory (GFDL) has included playing a key role in the development and application of state-of-the-art atmosphere and climate models to address major questions, e.g., the timescales of response to anthropogenic forcing and changes in tropical storms and Southern Hemisphere circulation under climate change.

Isaac is member of the National Academy of Sciences and a Fellow of AGU and the American Meteorological Society (AMS). He has received the AMS Carl-Gustaf Rossby Research Medal, Banco Bilbao Vizcaya Argentaria (BBVA) Frontiers of Knowledge Award for Climate Change research, and Presidential Rank Award of Distinguished Senior Professional.

Isaac’s scientific citizenship spans an amazing range. His elegant articulation of how global warming can enhance hydrological extremes, both wet and dry, was pivotal in the Intergovernmental Panel on Climate Change’s assessment (2007). His essays on large-scale dynamics, global warming, and climate modeling are lucid, thought provoking, and influential. His blog on climate dynamics is widely acclaimed for its wisdom and clarity. As a lecturer with the rank of professor in the Atmospheric and Oceanic Sciences Program at Princeton University, he has mentored more than 20 doctoral students and 30 postdoctoral scientists.

Isaac’s outstanding scientific accomplishments in atmospheric and climate dynamics make him one of the world’s foremost experts in climate science, a scientist extraordinaire truly worthy of Roger Revelle’s giant legacy in climate science and leadership.

—V. Ramaswamy, Geophysical Fluid Dynamics Laboratory, Office of Oceanic and Atmospheric Research, National Oceanic and Atmospheric Administration, Princeton, N.J.

Thanks, first of all, to my nominators and the selection committee. The Revelle Medal is a wonderful honor. I have had the great fortune of working at GFDL, a very distinctive NOAA laboratory, for 40 years, with the freedom to pursue my interests in atmospheric dynamics and climate change. I especially need to thank the lab directors who have supported me in interpreting NOAA’s mission—to understand and predict changes in climate, weather, oceans, and coasts—as encompassing even my most theoretical research. Let me first thank Ram, Dr. Ramaswamy, for his support in the most recent decade and, working backward in time, Ants Leetmaa, Jerry Mahlman, and, of course, Joe Smagorinsky. I was first drawn to GFDL and Princeton in the 1960s by reading Suki Manabe’s papers on climate modeling and global warming. Simply stated, Suki has the best holistic understanding, the best intuition, for how the climate system works of anyone I have ever met. Whatever success I have had has resulted in large part from some of Suki’s understanding and intuition rubbing off on me over the years. My motivation when I originally switched fields from theoretical physics was to focus on global warming. But I first went on a multidecade journey through basic atmospheric dynamics, searching for a more fundamental understanding of the general circulation of the atmosphere, before gradually turning to aspects of climate change. I would like to interpret this award as recognizing the journey as a whole and not a few discrete stops along the way. At every step on this journey, my work has depended on my graduate students at Princeton, my postdocs, and, of course, my colleagues within and outside of GFDL. I have accumulated too many debts over the years to mention individual names. Finally, let me thank my wife, Joann, who has received her share of awards for her environmental work, not on the global scale but rather on the scale of our township. She recently was officially designated a Force of Nature by a local environmental group. I haven’t figured out how to incorporate this force into the equations of motion in our models, but perhaps it is something that we can work on together in the future. —Isaac M. Held, Geophysical Fluid Dynamics Laboratory, National Oceanic and Atmospheric Administration, Princeton, N.J.