U.S. Energy Secretary Steven Chu warned an audience of 800 at SLAC National Accelerator Laboratory in Menlo Park on Friday morning that "business as usual" would lead to a dramatically changed world in the coming decades.

During his two-hour talk, similar to one he presented Thursday to executives of the electrical power industry gathered in San Francisco for an annual convention, he described a world with more severe storms and droughts, far more hot summer days exceeding 90 degrees, rising sea levels and species extinctions if carbon emissions aren't markedly scaled back.

At the SLAC event, he spoke easily and candidly to the audience, many of them colleagues from his time at Lawrence Berkeley Laboratory and Stanford University, where he held leadership posts. He seemed to relish the familiarity of both the setting and the many scientists gathered to hear his first address at the physics research lab since Chu became energy secretary hours after President Barack Obama's Jan. 20 inauguration.

He was a few minutes late for the speech, Chu said, as that morning he squeezed in a bike ride around "the loop," a well-known local circuit. His two-hour talk was punctuated with broad smiles and occasional jokes.

The subject he was addressing, however, was no laughing matter, he said. While the Energy Department is continuing its historic mission of developing new energy technologies and improving the efficiency of the nation's energy infrastructure, the grave threat posed by a changing climate is "the new 800-pound gorilla in the room," he said.

"Every year for me it gets more alarming," Chu said. "We really need to get moving on this."

Chu focused on a chart from a report released this month from the National Oceanic and Atmospheric Administration. That report was commissioned by the Bush administration in 2007, and was produced by a consortium of 13 U.S. government science agencies and several universities.

The chart tracked atmospheric carbon dioxide levels over an 800,000-year period, measured from an Antarctic ice core. In it, a red line ranged between 170 to 330 parts per million, or ppm, until present times.

By 2008, that level was 385 ppm, and was attributed to human activities. Without major reductions in greenhouse gas emissions, the line climbed to 900 ppm in 2100. But Chu warned that scientists now believe that atmospheric carbon dioxide beyond 450 ppm will lead to what he called a "tipping" point.

"We're really going off the scales," he said. "That's the scary part, and most people don't understand this in their hearts and souls."

Accompanied by slides showing current signs of climate change, Chu described in detail the consequences of rising temperatures in the coming century. While more rain would likely fall, most of it would come during the winter, and in large downpours, rather than lighter rains spread over weeks or months.

"So we'll have floods in the winter, but when you want to grow things, we'll get less," Chu said. Farmers, particularly in the West, will face conditions worse than those seen in the 1930s Dust Bowl, he said.

Ice sheets are also melting faster than predicted, he said, and scientists are now deeply concerned about the melting permafrost. Long-dead plants sequestered in the frozen ground, with their carbon contained, would release their carbon stores, and the microbes feeding on them release methane, a greenhouse gas hundreds of times more potent than carbon dioxide.

"It could be equal to one-third of all the (atmospheric) carbon dioxide, it could be twice," Chu said.

But his dire warnings were also meant to inspire members of both audiences. Officials with the Edison Electrical Institute, which held its annual convention in San Francisco this week, said the industry group supports the Department of Energy's many initiatives to increase the efficiency of the energy infrastructure, to reduce usage, and to develop new technologies.

And scientists, including those at SLAC, which conducts particle physics and other research, face a critical but doable challenge, he said.

"There are lots of exciting things for people at SLAC to think about, and they have to know it's a solvable problem," Chu said.

He outlined many of the strategies launched by a fresh infusion of federal funding. In California alone, the American Recovery and Reinvestment Act has funded projects totaling more than $1.1 billion, including Lawrence Berkeley Lab, Lawrence Livermore Lab and SLAC.

He described "smart grid" technology, in which computerized meters and other monitoring equipment would help distribute electrical usage during nonpeak times and increase energy efficiency. A pilot project is underway in the state of Washington, Chu said. He detailed numerous incentives under development for homeowners to increase energy efficiency. And a "geo-engineering" solution of creating white roofs and converting blacktop to light-colored concrete would save 20% in energy costs and deflect most of the solar energy back into space.

An audience member at SLAC asked Chu how he responds to those skeptical of the dangers posed by climate change.

"People are entitled to their own opinion," he responded. "But they're not entitled to their own facts."

He likened accepting the risks of climate change to accepting the risk of fire in a home. Even if there's only a 50% risk that a house is at risk due to bad wiring, for example, "Do you shop around for a structural engineer who will tell say there's no risk, or do you buy more fire insurance?" Chu asked.

"In the end, you're probably going to rewire your house, because the chances are the house will burn down at night while you and your family are in the house," he said.

Link to article: http://www.contracostatimes.com/science/ci_126992