By Daniel Strain

The National Research Council issued three major climate reports recommending that the United States act now to reduce greenhouse gas emissions and develop a national strategy to adapt to the inevitable impacts of global warming.

The three reports were commissioned by Congress in 2008 to inform and guide the nation's response to climate change. Pamela Matson, dean of the School of Earth Sciences at Stanford University, presented the findings of one report, Advancing the Science of Climate Change, at a May 19 news briefing in Washington, D.C. The report was prepared by a panel of 20 climate experts chaired by Matson.

"The core phenomena of climate change have been examined thoroughly and have stood firm in the face of scientific debate for several decades," said Matson, a senior fellow at Stanford's Woods Institute for the Environment. "The nation needs a comprehensive, integrated and flexible climate change research enterprise that is closely linked with action-oriented programs at all levels."

To accomplish that goal, the report recommended giving a single federal program the authority and resources to implement a national climate change research effort.

Affirming climate change

In the report, Matson and her colleagues affirmed that "climate change is occurring, is caused largely by human activities and poses significant risks for a broad range of human and natural systems."

Global temperatures have risen an average of about 1.5 degrees Fahrenheit in the past century, they wrote, and this hike is largely due to fossil fuel burning and other human activities that release greenhouse gases.

Rising temperatures could have big consequences for global ecosystems and humanity, Matson said, igniting a chain of events that could lead to more severe storms and even starvation worldwide. "Climate change is not just an environmental problem," she said. "It's a sustainability problem."

Impacts will vary at the regional level, she added. California, for example, could see an increase in droughts over the coming decades as Sierra Nevada snowpacks - which provide the state most of its freshwater - shrink. "We need to know more about climate change at the regional scale," Matson said.

Although the causes of global warming are well understood, there is still a great deal of uncertainty about the magnitude and rate of future climate change, the report said, noting that climate models project an additional warming of 2 to 11.5 degrees Fahrenheit by the end of the century.

Some of this uncertainty stems from the complexity of the Earth, Matson said. For example, estimates of sea level rise - anywhere from 0.6 feet to 6.5 feet - vary because scientists don't know all of the dynamics of how large ice caps melt, such as those over Greenland and Antarctica.

"We need to understand more about metrics and measures and processes to predict who's vulnerable and who's not to climate change," Matson said.

New era of research

In the report, Matson and her colleagues called for a "new era of climate science research." The panel recommended that scientists and policymakers form a national umbrella organization "aimed at improving both understanding and responses to climate change."

The U.S. Global Change Research Group, a collaboration of federal agencies established by Congress in 1989, could fulfill this role, but the agency would need to "address weaknesses" that have led to gaps in research on how best to respond to global warming.

"We need to focus not just on improving our fundamental understanding of climate change but also informing and expanding America's climate choices," Matson said.

The linchpin to this new era, she said, will be to build a dialogue between scientists and the people in government and industry who will make decisions on how to adapt and respond to change. "It's very important for scientists to understand what the concerns of decision-makers are so they can focus their attention in the right directions," Matson said.

Last week, members of the U.S. Senate introduced a comprehensive energy bill designed to cut greenhouse gas emissions nationwide. Matson said that she and other panelists hope that their recommendations will help inform this debate.

"If we understand what the challenges are, we will do a better job of developing the scientific information that will help them make good, effective decisions," she said. "We recognize that scientists aren't going to be the ones making decisions."

In addition to Matson, the panel also included Stanford researchers John Weyant, professor (research) of management science and engineering and senior fellow at the Woods Institute and Precourt Institute for Energy; and Ken Caldeira, associate professor, by courtesy, of geological and environmental sciences.

The National Research Council is administered by the National Academy of Sciences and the National Academy of Engineering. The mission of the council is to provide elected leaders, policy makers and the public with expert advice based on sound scientific evidence.

Daniel Strain is a science-writing intern at the Woods Institute for the Environment at Stanford University.