In June, as President Trump trolled the world with his long-anticipated “withdrawal” from the Paris Agreement, I wrote in this journal to observe that an abdication of federal leadership in this area, contrary to the despairing of many pundits, actually represented, at once, a golden opportunity: An expert, progressive, and eager California would step into the void and lead a global movement.

Indeed, California has been a steady voice of reason on the global climate stage. The State, in partnership with NGOs and other states, has joined a number of intergovernmental alliances designed to elicit subnational commitments to the larger Paris targets. Governor Brown traveled to the last Conference of Parties (COP23) in Bonn, Germany, in part to announce additional commitments to his “Under2MOU,” which has begun to stitch together a global quilt of state-level and municipal emissions reductions plans. As COP23 came to a close, California had already illustrated that that movement may be strengthening.

First, California’s utilities are building a completely renewable power sector.

California is on track to meet its 50 percent Renewable Power Standard as much as a decade early. The electric portfolio of San Diego Gas & Electric, for example, one of the state’s three investor-owned utilities, has already hit 43.2 percent renewable. The national average share of renewable energy consumption, according to U.S. Energy Information Administration, was about 10 percent. Getting to one hundred percent in California by 2050 is not far-fetched.

But perhaps more telling than the statistics is the recent history of one local project: the Puente Power Project. In October, the California Energy Commission issued an unprecedented statement in which it claimed that it intended to reverse its previous approval of a 262 MW natural gas-fired power plant. Coming on the heels of the state’s recent nuclear retirements, this denial suggests that investors will be hard-pressed to ever again build anything that isn’t primarily renewable plus storage. In other words, in a state that has historically applied a fairly liberal approach to its permitting of fossil fuel power plants, increasing pressure from clean energy advocates and local communities concerned about the public health impacts of more fossil fuel combustion has made further permitting of natural gas infrastructure unlikely. And the latest case study in Oxnard shows that the State’s regulators have validated the notion that California’s energy needs are serviceable by the wind and the sun, so long as that intermittent energy can be reliably stored and released by commercial batteries.

What does this mean for emissions? Well, the data is now in, and while the state achieved an impressive overall drop in carbon emissions of 4.8 percent between 2015 and 2016, the power sector’s contributions to this decline were stunning: Emissions from in-state electricity generation decreased by 19.3 percent, and emissions from imported electricity dropped by 22.7 percent. The slow and steady march of the state’s utilities toward decarbonization—a project that has been accelerated by the increasing competitiveness of wind and solar power generation in the global power market—is already reaping dividends for the security of our climate.

Second, automakers are paving a path toward zero emissions transportation in California.

Since the 1960s, California’s leadership in advanced, clean cars has been steadfast. The state is now fomenting a quiet revolution in the development of cleaner heavy-duty vehicles as well. Emissions from big trucks represent the lion’s share of climate pollution: According to the Union of Concerned Scientists, heavy-duty vehicles make up 7 percent of California’s vehicles, but represent 33 percent of NOx emissions, 20 percent of climate pollution from the transportation sector, and are responsible for more particulate matter than all of the state’s power plants combined.

But technology companies and social justice advocates have successfully articulated the case for why electric buses and trucks can reduce emissions, improve public health, and reduce costs for consumers. 2017 has been the year of electric commitments: Just this month, the City of Los Angeles joined more than a half-dozen additional local and regional jurisdictions committing to 100 percent zero-emission bus fleets. These commitments hold the promise of cleaner air and cheaper transit—they also mean more local jobs (manufacturers Proterra and BYD have each cut ribbons this year on new or expanded manufacturing facilities in Southern California). If the market’s reception to Elon Musk’s semi-truck unveiling is at all akin to the one we’ve seen for the Model S, it may perhaps represent the beginning of the end for diesel trucks entirely.

It is critical to remember that this is happening in California because grassroots community leaders have focused not on cleaning up our climate, but on making their communities healthier. As a result, a focus on addressing local air pollution—which was the same motivation that initially led to the catalytic converter 50 years ago—has encouraged new zero-emission technologies and the electrification of our transportation infrastructure.

It must be noted that, notwithstanding this welcome news, the data also show California’s transportation sector headed still in the wrong direction: Even though the state reduced its carbon emissions between 2015 and 2016, climate pollution from cars and trucks actually rose during that period, thanks to cheap gas. But as the emissions data continues to trend up, the state’s focus on electrification holds the promise of an imminent inflection point in our mobility sector that will finally decouple miles driven—or the price of a barrel of oil—from vehicle emissions. Of course, in order for this to work, the electric grid must in fact approach 100 percent renewable: An increasingly electric fleet of vehicles will draw more and more on the grid to fuel its mobility, yet our transportation-driven emissions will only be as decarbonized as the grid itself. (Good thing the power sector is headed in the right direction.)

Finally, thanks also to the work of social justice advocates, California has begun to achieve a vision for equity in our energy transformation. The delegation from California to COP23 was there to highlight that message: Policies to mitigate climate change cannot just be about protecting polar bears, they must be about protecting people.

Unfortunately, this also meant that the delegation was obligated to report on a critical and inconvenient truth about climate pollution that cannot be avoided, in even the world’s most progressive major economy: In places like Los Angeles, although emissions have fallen, smog has increased for the last two years in a row. The local air regulator, the South Coast Air Quality Management District, chalks up the increase in smog to more days with both hotter temperatures and inversion layers, which trap cold air—and smog—close to the ground (thanks, Global Warming). We know that climate pollution and poor air quality are not equitably distributed among the rich and poor. (Take a look at “hyper-local” emissions mapping in California for a sense of which neighborhoods experience the worst air pollution.) Exposure to emissions, proximity to major transportation corridors and other sources of pollution—usually compounded by a lack of open space, public transit, and socioeconomic burdens, such as high unemployment and poverty—lead to higher rates of respiratory disease, cancer, missed school days for children and parents, primarily in disadvantaged communities. That is why in 2016, when California enacted sweeping new climate pollution reduction laws, it did so in tandem with climate justice legislation, which required new standards for transparency, equity, and accountability; and that’s why this year’s legislation—AB 398 (cap-and-trade extension) and AB 617 (local air pollution reduction)—came similarly paired. These laws reflect California’s climate avant-garde: We cannot move forward on a global challenge without first addressing local injustices.

There’s clearly more to do. Notwithstanding all of California’s work, there is still an Administration in Washington hostile to progress on this issue. That America was on display at COP23 also: As global leaders convened in earnest to address the imminent threat that climate change poses, the United States’s sole contribution to the public agenda was a panel of fossil fuels experts who came to express their oft-repeated message: “We’ll be here for a while.” Mayor Bloomberg proclaimed that such a stunt was akin to bringing tobacco to a cancer conference. It was certainly counterproductive; but ultimately, it was a distraction. Where advocates, businesses, and policymakers are focused on real innovation, and addressing tough challenges that will require resolve and resilience—like transforming our mobility infrastructure, rather than simply promoting the status quo—there is a very hopeful story to see. Just take a peek at California.