The scientific method requires that we keep an open mind and change our conclusions when new evidence indicates that we should. Climate change is the new evidence affecting the nuclear debate -- we need low-carbon energy. Current (2nd generation) nuclear reactors are not as fail-safe as possible and they burn less than one percent of the energy in uranium ore. Next (3rd) generation reactors are safer, shutting down automatically in case of anomalies, and are ready to go, but they still leave 99 percent of the energy in long-lived waste piles. 4th generation reactors, tested but not commercially available, can extract all of the energy in the nuclear fuel and burn nuclear waste. We urgently need R&D to make the combination of 3rd and 4th generation reactors available with comprehensive international controls.
James E. Hansen heads the NASA Goddard Institute for Space Studies in New York City. He has held this position since 1981. He is also an adjunct professor in the Department of Earth and Environmental Sciences at Columbia University.
After graduate school, Hansen continued his work with radiative transfer models and attempting to understand the Venusian atmosphere. This naturally led to the same computer codes being used to understand the Earth's atmosphere. He used these codes to study the effects that aerosols and trace gases have on the climate. Hansen has also contributed to the further understanding of the Earth's climate through the development and use of global climate models.
Hansen is best known for his research in the field of climatology, his testimony on climate change to congressional committees in 1988 that helped raise broad awareness of global warming, and his advocacy of action to limit the impacts of climate change.