KQED: President Obama this week urged Congress to act on climate change. Thursday, California Senator Barbara Boxer answered that call, with a new bill to curb carbon pollution. Senator Boxers bill would charge a fee for carbon emissions, starting at $20 a ton, and rising over the next decade. "The science is telling us that we cant waste any more time, and the weather is showing us that we cant waste any more time," Boxer said. The revenue generatedpotentially more than a trillion dollars--would...