29 December 2011
Factors contributing to climate change are moving faster than predicted and pushing us toward planetary conditions unlike any humans have ever known—this was one of the salient themes to emerge from this month's meeting of the American Geophysical Union, the world's largest gathering of earth and space scientists. Some scientists think we've already crossed that boundary and are, as Jonathan Foley, director of the University of Minnesota Institute on the Environment, said, "in a very different world than we have ever seen before."
What scientists are now witnessing as the earth responds to increasing levels of atmospheric greenhouse gases presents many of them with a dilemma: How far should they go in expressing their concerns about how government and society are responding to climate change? This question is particularly charged given that efforts to undermine climate science have become part of the political debate on these issues.
Running through the meeting's scientific presentations were formal and informal discussions about the scientist's role in guiding society's response to climate change, including how to effectively communicate the certainties and uncertainties of the science—and how to respond to what Don Wuebbles, University of Illinois professor of atmospheric science and chair of the organization's Global Environmental Change committee, called the "confusionists."
After the meeting, InsideClimate News interviewed several leading climate scientists and a renowned science historian to get a sense of how they are navigating this difficult terrain. All of them have testified before Congress and several were contributing authors on the 2007 report of the Nobel Prize-winning Intergovernmental Panel on Climate Change (IPCC), so all understand the challenges of working in the public spotlight.
When it comes to the certainties of climate science, all of them agree that the scientific literature has established definitively that rising atmospheric carbon dioxide levels have led to global warming and that anthropogenic fossil fuel burning is a major factor in this rise.
"The bottom line is that the climate system is telling us an internally and physically consistent story," said Benjamin Santer, an atmospheric scientist at Lawrence Livermore National Laboratory who delivered the 2011 AGU Stephen Schneider Memorial lecture. "While there will always be sizable scientific uncertainties, there can be no reasonable debate about whether the planet is warming," or that fossil fuel burning is a prime contributing factor, said Santer, an IPCC report contributor, whose work linking climate change with anthropogenic factors has been attacked by climate change skeptics. […]