Kevin Trenberth
Distinguished Senior Scientist

Winner of the 2017 AGU Roger Revelle Medal

Courtesy of Guardian News & Media Ltd. written by John Abraham on July 27, 2017 [Article]

The American Geophysical Union - the pre-eminent organization of Earth scientists - presents annual awards to celebrate the achievements of scientists. The awards, which are often named after famous historical scientists, reflect the contributions to science in the area of the award namesake. With the 2017 award winners just announced, it’s appropriate to showcase one of the winners here.

The 2017 winner of the Roger Revelle medal is Dr. Kevin E. Trenberth. One of the most well-known scientists in the world, he is certainly the person most knowledgeable about climate change that I know

The Roger Revelle award is given to an honoree who has made outstanding contributions to the understanding of the atmosphere and its interactions with other parts of the climate system. Named after Roger Revelle, who was critical in bringing the idea of human-caused climate change to the scientific community, it is amongst the highest honors. Named after Roger Revelle, who was critical in bringing the idea of human-caused climate change to the scientific community, it is amongst the highest honors. Revelle wrote regarding increasing carbon dioxide in the atmosphere in 1957: "human beings are now carrying out a large scale geophysical experiment".

Certainly the other scientists nominated were of incredible quality. Why was Kevin granted the award? I cannot answer this for certain because I was not on the committee, but it’s possible that he won strictly because of his scientific contributions.

Dr. Trenberth is a leading voice in the concept of Earth Energy Imbalance (which is really the rate of global warming). He also pioneered research related to the interactions of the atmosphere with the oceans, particularly the El Niño/La Niña cycle. He has worked on advancements to climate models and to experimental observations of climate. Another major area of contribution is the changes in precipitation with climate change, and especially the frequency and intensity of extremes. He has also changed the approaches to attribution of human-caused climate change.

But perhaps Dr. Trenberth won the award because of the sheer volume and impact of his scholarship. He is closing in on 70,000 citations to his work. This puts him near the top of the list worldwide for impact.

Or maybe he won because of his tireless efforts in service to the scientific community, with leadership roles in the IPCC, the World Climate Research Programme, NOAA, and other groups. Or lastly, it could be because he is tireless as both a researcher and a communicator. Dr. Trenberth can be heard or read almost weekly in major newspapers, magazine articles, radio and television shows. When reporters need complex climate science explained, he is a go-to person, and has been for years.

His personal life is interesting too. Born in New Zealand, he studied mathematics before embarking on meteorology. His time in New Zealand provided him with a different geographic perspective than his American and European colleagues. New Zealand is more impacted by certain climate oscillations, like fluctuations in the temperature of the Pacific Ocean surface waters. Certainly these experiences affected his climate views.

Growing up, family, school, and sports – he was a top rugby player - were important. He was somehow able to balance these three pillars of life without sacrifice to his academics. Born into a family of very modest means, Kevin had to make his own fortunes. His early academic performance resulted in financial scholarships for school.

After some time spent in the New Zealand army, he was ready to embark upon his scientific career. After winning a New Zealand government fellowship to do his doctorate at MIT, he met his future wife Gail who was as ever energetic, smart, and involved in life as was Kevin. They had a daughter in New Zealand, and, after moving to the U.S. as a professor at the University of Illinois, began fostering, which led to the adoption of their second child.

Somehow Kevin and his wife kept both career and family center in their lives and Kevin’s reputation as a top-rated scientist increased. He moved to the National Center for Atmospheric Research in 1984. His scientific work and his public communication efforts meant that he became a frequent target of groups that try to deny human-caused climate change or diminish its importance. The problem with Kevin is, he knows so much you can just assume he is smarter than you.

Well-known contrarians such as Richard Lindzen, Roy Spencer, and John Christy have had their works rebutted by Trenberth for technical errors. Trenberth has also crossed paths with vocal down-players of climate change like Roger Pielke Jr., who reportedly threatened Trenberth by email. Pielke Jr. was working for Nate Silver’s 538 website; his actions lead to Nate Silver stating “We had candid conversations with Michael Mann and Kevin Trenberth (about the emails). We made clear that Roger’s conversations with them did not reflect FiveThirtyEight’s editorial values.”

Why would I write about this aspect of Trenberth’s career? Because it shows that he has suffered slings and arrows for his tireless work. He has spent his career being honest about the limits of our knowledge of the Earth’s climate but also being clear about our certainty of human-caused climate change. His reward for this tireless service to society has been attacks on his research and his person. However, he has been impeccable in character and scholarship. The ill-advised who tangle with Trenberth have discovered they are on the short end of the intellectual battle.

It is my view that the AGU, by granting awards such as these to scientists, effectively encourage others to reach the highest standards in their profession.

Interested readers can go here to read about the other AGU award winners for the 2017 year or view the complete January magazine here that features his nomination and acceptance speech.

View the nomination and acceptance speech full screen

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Roger Revelle Medal 2017

Kevin E Trenberth

Generic medal: For outstanding contributions in atmospheric science, atmosphere-ocean coupling, atmosphere-land coupling, biogeochemical cycles, climate or related aspects of the Earth system.

The Nomination

Trenberth: For outstanding contributions to climate change and understanding how the climate system operates and for dedicated leadership in climate sciences.

Kevin Trenberth is being recognized for his outstanding contributions to understanding how the climate system operates, for gaining critical insights into the nature and future of climate change, and for his unusually dedicated leadership in the climate sciences. He is also being recognized for an almost unparalleled passion for climate science debate and communication. To interact with Kevin is not only to keep on your toes, it also is to get fired up and learn.

Kevin Trenberth’s scientific productivity is astonishing: he has published over 500 scientific articles or papers. He is listed among the top handful of authors in highest citations in all of geophysics, and he has a staggering H-index.

An abbreviated summary of his primary areas of contribution include: attribution of climatic events, heat budgets, dataset development and climate information systems, research on ENSO, the water cycle, the mass of the atmosphere and southern hemisphere meteorology.

Kevin has been perhaps the most significant contributor on the planet to our understanding of the Earth’s energy budget – an area of inquiry that is vital to understanding climate change and climate variability. His success derives from sheer productivity combined with multiple lenses through which he learns, including foci on ocean heat content, sea level change, models, and satellite measurements. He recognizes challenges before others, and invests enormous effort in solving them.

Kevin has led international teams to close the Earth’s energy budget and provide robust updates to our planet’s growing energy imbalance. His work on energy has also linked and quantified sensible heat, latent heat and kinetic energy flows in the atmosphere and the processes responsible for the transports, in particular, the roles of mid-latitude storms, the Hadley circulation, monsoonal circulations, and planetary-scale quasi-stationary waves. Kevin’s insights go deep, but also far and wide in the field of climate science.

Kevin has flown many miles in service of the climate community, and this is appreciated by more colleagues than he will ever know. Kevin is driven by passion to learn and to help society come to grasp with what is happening to our climate system and why. This passion inspires as well, and Kevin has often taken the time to mentor his more junior colleagues on the ways of the climate system, ways of knowing about the climate system, and ways of communicating climate system knowledge with society.

Kevin’s recent leadership in the area of climate attribution deserves special attention. His push to provide more useful insights to policymakers builds on his heat budget expertise, but also on common sense. This highlights what is driving Kevin Trenberth – to learn what must be learned, and to make sure society understands the implications before it is too late. Like Roger Revelle, Kevin Trenberth has served both the scientific community and society in many ways that will long be remembered.

John P. Abraham
University of St. Thomas
St. Paul, Minnesota
Jonathan T. Overpeck
University of Arizona
Tucson, Arizona


I am thrilled and honored to receive AGU’s Roger Revelle medal. Roger was the scientist who wrote in 1957 "Human beings are now carrying out a large scale geophysical experiment of a kind that could not have happened in the past nor be reproduced in the future." I was fortunate to meet him at a National Research Council workshop in November 1990, not long before he died in July 1991. I was an invited speaker talking about climate change, El Niño and water, and Roger asked a question about El Niño and carbon dioxide: the issue being that during El Niño, upwelling of carbon and nutrient-rich waters along the equator ceases, lowering CO2, but offset by more drought and wildfires over land, and less uptake by warmer oceans, leading to an increase in atmospheric CO2.

In my career, which began in New Zealand, I have always had a global perspective. I began as an atmospheric scientist, but became involved at an early stage in El Niño research, which meant interacting with oceanographers, and I became what was really a first-generation climate scientist. I was privileged to become conversant in both fields and hydrology, and to see how these sciences have changed to become more global, with fewer proprietary data; instead there is widespread data sharing and global reanalyses of atmospheric and the ocean data, which I was fortunate to help develop and exploit.

I wish to especially thank the nominators, in particular: John Abraham led the effort with Jon Overpeck, plus support from Tom Karl, Mike Mann, Mike Wallace, John Kutzbach and Warren Washington. Thanks also to Jim Hurrell, the NCAR Director, and other NCAR colleagues, and my family for their support.

Being heavily involved in WCRP and IPCC, and caught up in the so-called climategate debacle, I was pushed toward becoming much more involved in communicating climate science to the public than is my introverted nature. Even today, many scientists, let alone the public, are not fully conversant with climate science and attribution, especially for extreme events (although I have a fan in Al Gore). With deniers in the White House and Washington, good communication about climate science has become even more important. Please join me in recognizing that science is not about beliefs, but rather is evidence driven. You might say that science trumps ideology! I am sure Roger Revelle would think so.

Let’s Make America Cool Again!

Kevin E Trenberth
National Center For Atmospheric Research
Boulder, Colorado