Science reports:

For climate advocates in the United States, the past month felt like a roller coaster. In early July, negotiations in Congress on clean energy legislation of historic proportions collapsed, and the effort seemed doomed. But backroom talks continued and last week key senators suddenly announced an agreement on a $369 billion bill that would provide the most climate funding ever seen in the United States. “It was the best kept secret, potentially, in Washington history,” says Leah Stokes, a political scientist at the University of California (UC), Santa Barbara.

The backers—Senate Majority Leader Chuck Schumer (D–NY) and Senator Joe Manchin (D–WV), who had initially balked at the cost—announced that the draft bill would ensure U.S. carbon dioxide (CO2) emissions would fall by 40% by 2030, compared with 2005.

Sponsors of the bill, which must still pass the full Senate and House of Representatives, might be expected to oversell its impact. But energy and climate modelers have now scrutinized its 725 pages and concluded the 40% claim is about on target. They plugged key provisions, including subsidies for renewable energy and tax cuts for electric vehicles, as well as controversial incentives for the fossil fuel industry, into their models. Two such models conclude that if the bill becomes law, U.S. greenhouse gas emissions would fall by about 40% by 2030, although only part of that stems from the bill alone. One model also finds that the renewable energy subsidies will likely create 1.5 million jobs and prevent thousands of premature deaths from air pollution, especially in disadvantaged communities.

“It’s a historic step, no doubt about it,” says Marshall Shepherd, an atmospheric scientist at the University of Georgia and former head of the American Meteorological Society. “It really does a lot to enhance the transition to a renewable energy economy.” [Continue reading…]