California Gov. Jerry Brown (D) speaks during the United Nations Climate Change Conference at the U.S. Embassy in Paris on Sunday. (Michel Euler/Associated Press)

At the Paris Climate Change Conference, the world’s nations are pledging their first real steps toward addressing catastrophic climate change. Yet in this country, Republicans in Congress are already vowing to block President Obama’s program, while their presidential candidates scorn scientists’ alarm. Even if Democrats hold the White House in 2016, inaction and obstruction will remain the order of the day in Washington.

California Gov. Jerry Brown (D) says, “Somebody has to wake up the country to the real danger” and break the stalemate in Washington. And he is nominating himself to be that somebody.

Brown led a major delegation of state officials to Paris and garnered international attention, arguing that “the real source of climate action has to come from states and provinces. . . . We’re going to build up such a drumbeat that our national counterparts — they’re going to listen.”

Brown, along with Washington Gov. Jay Inslee (D), has championed the Under 2 MOU agreement, under which provinces and states across the world pledge to meet the target scientists say is the bare minimum: limiting the global average temperature change to under 2 degrees Celsius. That will require signatories to reduce emissions 80 to 95 percent below 1990 levels by 2050. In Paris, Brown noted that the more than 50 regions and states that have signed on represent what would be the largest economy in the world.

This year, Brown issued an executive order designed to reach that goal. It requires California to cut greenhouse gas emissions in California 40 percent below 1990 levels by 2030 — the most ambitious target in North America — and is consistent with California’s commitment to reduce emissions 80 percent under 1990 levels by 2050.

This requires dramatic changes across the board. In his inaugural address this year, Brown announced that utilities would have to get 50 percent of their energy from renewable sources by 2030 and California would seek to double efficiency savings from existing buildings. Industries will have to cut smokestack releases. Electric cars will have to become affordable enough to capture a huge portion of the market.

California’s action matters. On its own, the state represents the seventh-largest economy in the world (neck and neck with Brazil). It has sufficient size and clout to help make markets, to drive innovation and to force companies and industries to alter their plans and product lines.

The scope of the needed changes is breathtaking. A recent analysis by E3, an environmental consulting firm, estimated that the state could need as many as 8 million zero-emission vehicles on the road by 2030 to meet Brown’s goals. There are only about 150,000 such vehicles on the road now. That gives the state 15 years to have 60 percent of the state’s motor vehicles be free from the internal combustion engine.

This year, California legislators defeated a bill that would have written Brown’s pledges into law, with some Democrats voting no, fearful of a commitment to cut petroleum use in motor vehicles in half in 15 years. But Brown argues that the California Air Resources Board has the authority it needs to work toward those goals in any case.

And Brown is backed by popular opinion in the state. According to a recent poll by the nonpartisan Public Policy Institute of California , 52 percent of Californians consider climate change to be a “very serious” problem. Interestingly, Latinos are more concerned than white adults and the young (18 to 34) more concerned than older residents (55 and older). Mired in the worst drought in state history, Californians are likely to grow more concerned, not less.

Can states and municipalities — blue states and cities in particular — drive the reforms we so desperately need? We’ve seen the stirrings on other issues, such as when cities and states have moved to raise the minimum wage, while Republican leaders in Congress won’t even allow it to come to a vote. We’ve seen it in New York, where Mayor Bill de Blasio is raising taxes on the wealthy to pay for universal prekindergarten . And now, under Brown’s leadership, California is driving the call for action on climate change. Once more, California may be shaping our future.

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