The state’s greenhouse gas emissions in 2016 were less than were emitted in 1990. That’s a target the state is required to meet by 2020 under AB 32, the landmark climate change law.
"I think it's a very positive signal and an affirmation that we're on the right track," says Michael Benjamin, chief of the Air Quality Planning and Science Division at the California Air Resources Board.
With solar power booming, the major drop in emissions came from the electricity sector. Solar rose by 33 percent, as the state’s utilities continue to turn on renewable projects. California law requires them to get half of their electricity from renewable sources like solar and wind by 2030.
Wet weather in 2016 also provided a boost. Power from imported from out-of-state hydroelectric dams, which is considered carbon-free, rose by 39 percent.
During dry years, California uses less hydropower and more natural gas or other fossil fuels. But Benjamin says he doesn't think a dry year would jeopardize California's milestone in the future.
“I wouldn’t say that we’d necessarily be above 1990 levels and if we were, I don’t think we’d be significantly above,” he says. "What’s happened is this continued good news story about solar.”
Still, emissions rose from California’s largest source: cars and trucks. It increased by 2 percent in 2016, continuing a steady rise as the economy has recovered. Those emissions fell during the recession because Californians were driving less and less freight was being moved.
While cars and trucks have gotten more efficient, today drivers are buying bigger vehicles. The state is trying to encourage drivers to buy electric cars in order to meet a goal of 1.5 million zero-emissions vehicles on the roads by 2025.
California’s overall emissions peaked in 2004 but have fallen by 13 percent since then.
The state now is reaching for an even more ambitious goal: cutting emissions to 40 percent below 1990 levels by 2030.
To hit that, officials at the California Air Resources Board say the state will have to double the rate of emissions cuts. That would require a major shift in the kinds of cars Californians drive.
"This has been the easy part," Benjamin says. "The early reductions are the easiest and least expensive. But at the same time, I think in transportation we will start to see a tipping point as the relative cost of electric vehicles gets lower."
That long-term goal could also be hampered by the Trump Administration, which has moved to limit some of the air quality and climate programs California has put in place.
“There’s always the threat that the federal government’s actions will limit our progress,” Benjamin says. “Be we here in California are pushing back extremely hard. We know what we need to do to protect the environment."
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