Dr. James Hansen's rigorous study of climate change and its implications

Despite recent interest in climate change, the public and policymakers are not well informed about the status of understanding and the implications of that understanding. It is essential therefore to realize that stabilization of climate is possible and does not need to be costly. Indeed there would be many economic advantages in moving promptly to clean energies. The barriers however, include the fact that there are so many parties affected by energy policies that the cacophony can make it difficult for the public and even policymakers, to understand what is necessary. In this situation, broad-based unbiased scientific analysis, communicated clearly, is crucial.  

Dr. James Hansen, of Columbia University, is working to analyze and understand the physics of climate change and then to communicate the unbiased scientific knowledge he gathers to the public in a way that is understandable. It is his philosophy that it is necessary for scientists to connect the dots all the way from the causes of climate change to the implications for public policy. His research investigates the consequences of alternative energy pathways with a broad approach that employs analysis of Earth's climate history, use of climate simulations, and analysis of modern observations of on-going climate change today.

Dr. Hansen has demonstrated scientific rigor coupled with the courage to tell policymakers and the public the truth about the current situation of our planet. He has had a major hand in founding and developing several organizations including, 350.org, Citizens Climate Lobby, and Our Children's Trust. His first book, Storms of My Grandchildren highlighted the importance of action in light of climate change and his numerous awards and honors including the Blue Planet Prize, the Sophie Prize for Environmental and Sustainable Development, and the Ridenhour Courage Award, highlight his commitment to the welfare of our planet. Dr. Hansen is currently completing his most important paper to present prior to the crucial December 2015 climate negotiations that will be held in Paris, France. He hopes to make clear the target of keeping human-made global warming to 2 degrees Celsius is in fact inadequate and dangerous.  Although lower targets are feasible and economically sensible, Dr. Hansen argues that target-emphasis allows governments to dodge responsibility.  Instead policy-emphasis is crucial for success.

Dr. Hansen's research is unusual because it combines several different avenues for understanding environmental problems. The avenues he explores are:

  • Paleoclimate: Dr. Hansen studies Earth's climate history in order to understand how the earth responded in the past when things such as atmospheric composition changed.

  • Climate Simulations: Dr. Hansen builds and uses global models for climate change. These simulations become tools for understanding how and why the Earth's climate is changing rapidly.

  • Modern Observations: Dr. Hansen is observing the Earth's environment including especially oceans, ice shelves, and sea ice to better understand what is changing and why.

  • Integration of Approaches: Dr. Hansen integrates his work with paleoclimate, climate simulations, and modern observations to approach climate change and environmental science from a new perspective. This holistic approach allows him and his team to see what is happening and has implications for what the approaches for targeted interventions need to be.

  • This profile is spotlighted in the Clean Energy Impact Fund.


Dr. James Hansen, formerly Director of the NASA Goddard Institute for Space Studies, is an Adjunct Professor at Columbia University's Earth Institute, where he directs a program in Climate Science, Awareness and Solutions. Dr. Hansen is best known for his testimony on climate change in the 1980s that helped raise awareness of global warming. He is a member of the U.S. National Academy of Sciences and has received numerous awards including the Sophie and Blue Planet Prizes. Dr. Hansen is recognized for speaking truth to power and for outlining actions needed to protect the future of young people and all species on the planet.

Dr. Hansen was lucky to be in Iowa, where Professor James Van Allen built the scientific instrument on the first United States satellite, with which he discovered the Earth's radiation belt. Dr. Hansen got caught up in the excitement of his department and research program, and was fortunate to catch Professor Van Allen's eye when, along with another senior, he was the first undergraduate to pass the Physics Departments Ph.D. qualifying exams.  Professor Van Allen told Dr. Hansen about new data on Venus, which led to his Ph.D. thesis analyzing alternative reasons for Venus being so hot. After getting his Ph.D., he joined NASA and proposed an instrument to study the properties of the clouds of Venus. As that instrument was being built, he became aware that several gases in Earth's atmosphere were increasing because of human activities, and realized that it was more important and interesting to investigate the ramifications of the changing atmosphere on our own planet. He thus proposed and received support for initiation of a climate research program at the NASA Goddard Institute for Space Studies.

Website: www.columbia.edu/~jeh1 ,  http://pubs.giss.nasa.gov/authors/jhansen.html  , and http://csas.ei.columbia.edu/


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NASA Distinguished Service Medal 2013

Foreign Policy designation as one of its Top 100 Global Thinkers, 2012

Blue Planet Prize, Asahi Glass Foundation, 2010

Sophie Prize for Environmental and Sustainable Development, 2010