California Governor Jerry Brown signed landmark legislation Monday committing his state to a 100 percent clean electricity grid by 2045.
At least 20 countries and twice as many large cities have made similar pledges, but California – the fifth largest economy in the world – is by far the biggest jurisdiction to do so to date.
"This bill and the executive order put California on a path to meet the goals of Paris and beyond," Brown said at a signing ceremony in state capital Sacramento.
"It will not be easy. It will not be immediate. But it must be done."
The Ferry Building is seen as crowds march up Market Street during the "Rise For Climate" global action on September 8, 2018 in downtown San Francisco, California. /VCG Photo
On the international stage, California has emerged as a leader on climate action as US President Donald Trump has opted out of the landmark 2015 Paris climate treaty and moved aggressively to dismantle the policies of his predecessor, Barack Obama.
"California, as a very prosperous economy, is taking aggressive action on climate change," Brown told AFP by phone when asked if the new measure will inspire others.
"So I hope it gets France and Germany to up their own ambition because we all have to do more than we are currently doing."
The electric sector represents 16 percent of the state's greenhouse gas emissions. More broadly, California has set ambitious goals to slash greenhouse gas emissions 40 percent by 2030, compared to 1990 levels.
Later this week, Brown will host subnational governments, cities, and businesses in San Francisco for the three-day Global Climate Action Summit.
Among the co-chairs is China's former chief climate negotiator, Xie Zhenhua, reflecting the strong ties that California has forged with China – at both the national and provincial level – around climate action.
"It's impossible to overstate how significant it is for a state as large and influential as California to commit to 100 percent clean energy," said Sierra Club Executive Director Michael Brune.
"California is showing the world that a transition to 100 percent clean energy is within reach."
But Brown cautioned that reducing emissions enough to meet the Paris goal of capping global warming below two degrees Celsius (3.6 degrees Fahrenheit) remains a daunting task.
"Have no illusions," Brown said. "California and the rest of the world have miles to go before we achieve zero-carbon emissions."
(Cover: Crowds march up Market Street during the "Rise For Climate" global action on September 8, 2018, in downtown San Francisco, California. /VCG)