Feb. 20, 2008
BLOOMINGTON, Ill. – The moment is coming. The Earth is reaching a point of danger from which it cannot be rescued.
This was the message of James E. Hansen, an expert on climate change and the Director of the National Aeronautics and Space Administration (NASA) Goddard Institute for Space Studies, at the address for Illinois Wesleyan University’s annual Founders’ Day Convocation Tuesday in Westbrook Auditorium. Hear Hansen's talk.
“Change is essential if we are going to keep the planet that looks like the one we live on now,” said Hansen, who has been studying global warming for more than 20 years. An author of numerous articles and scientific studies on climate change, Hansen has testified his finding before Congress. His speech, titled “Climate Tipping Points: The Threat to the Planet,” called upon young people in the audience to slow the devastating damage being done to the planet through the use of fossil fuels.
“Fossil fuel interests think it is a God-given fact that we will burn all the fossil fuels in the next few decades,” said Hansen, “but we have free will. Young people can say, ‘Hey, not so fast, nice planet you are leaving us,’” said Hansen.
Hansen encouraged the audience, dominated by students, to advocate changes, such greater use of renewable fuels, the implementation of no-till agricultural practices and the building of coal-burning facilities that capture carbon. “The future is inherited by young people. They can influence elections and impact global change.”
The title of the talk comes from Hansen’s fear that the Earth is reaching an irreversible tipping point with global warming. “A tipping point is when the dynamics of a system take over from nature and cause relatively large and fast change,” he said. “When we hit a tipping point, things will really move fast.”
One such tipping point has already been reached, according to Hansen, with ice in the Arctic and Antarctica that has been disappearing at an alarming rate. The ice sheets have been growing thinner and thinner over the past few decades, and suddenly saw a 20 percent drop over last summer. “I think we have probably reached a point where we are going to lose all the summer sea ice in the summer,” he said.
Armed with millions of years of scientific data, Hansen displayed charts and complex mathematical equations with statistics dating back to the Cenozoic era. New technologies have allowed scientists to gather exact data on the Earth’s changing climate with the help of ice core samples that show heat fluctuations through the measurement of snow and ice accumulations, much like looking at the rings of a tree. The Earth has experienced natural warmings and coolings, said Hansen, but never on as dramatic a scale as it has been over the past few decades.
The changing climate carries with it a domino effect, said Hansen. As ice caps melt, habitats disappear. “We know from the history of the Earth that there have been occasions of large global warming of several degrees, that have resulted in the extinction of species,” said Hansen, “and if we go down that path, we will be leaving a much more desolate planet.”
The loss affects more than animals. “With the ice sheets melting, the sea level is going to go up a lot,” said Hansen, who noted even a change of two to three degrees for the Earth would mean dramatic changes. “The last time it was that warm, the sea level was 25 meter higher, which would mean many areas – the east coast of the United States, including Florida, the entire nation in Bangladesh and about 300,000 people in China – would be underwater. More than half of the cities of the world are on coastal regions,” he said.
The need to act now is critical because it could take the Earth decades, even centuries to regain its balance, Hansen said. “Say we wanted to stop the ice from melting further. We would have to restore the planetary energy balance. Even if we stop carbon dioxide (CO2) emissions today, additional warning would occur because of the inertia in the system,” said Hansen, meaning areas such as the oceans hold onto the carbon emitted for years and break it down much more slowly than it is being put into the atmosphere.
Even as the Earth stands on the precipice of global change, Hansen can see hope for the planet. “There can also be a tipping point of social change,” said Hansen. “If we follow business as usual, then the Earth will warm past a point of no return. But, if the public, government and business would decide to work on the same side, and make rules that encourage energy efficiency, then we really could begin to make a change and avoid destroying creation.”
A member of the National Academy of Sciences, Hansen has twice received the NASA Presidential Rank for Meritorious Executive Award. He has been awarded the John Heinz Environment Award in 2001, the Roger Revelle Medal from the American Geophysical Union in 2002, the Duke of Edinburgh Conservation Medal from the World Wildlife Fund in 2006 and the Leo Szilard Lectureship Award from the American Physical Society in 2007. Named one of Time Magazine’s 100 Most Influential People in 2006, he has been director of the Goddard Institute since 1981.
Rachel Hatch (309) 556-3960