Anti-fracking advocates were cautiously optimistic Tuesday after California Gov. Gavin Newsom announced a moratorium on fracking in the state and new steps to mitigate the disastrous public health effects that extractive industries have on communities.

Author and 350.org co-founder Bill McKibben credited "relentless organizing" with pressuring the Democratic governor to ban—at least temporarily—the high-pressure steam injection central to the fracking process and pledge to reverse the increase in drilling permits that's taken place under Newsom's administration.

"It's not all that activists wanted, but that language is an important signal," McKibben wrote of the temporary fracking ban.

Newsom announced that, along with the fracking lease moratorium, the state would also commission an independent audit of regulators tasked with overseeing the oil and gas industries and would have federal scientists conduct third-party reviews of all drilling lease requests going forward.

The state will also strengthen protections for communities near oil and gas wells.

"These are necessary steps to strengthen oversight of oil and gas extraction as we phase out our dependence on fossil fuels and focus on clean energy sources," Newsom said.

The governor's response to years of anti-fracking campaigning in California shows "that the future of climate leadership means saying 'no' to the fossil fuel industry's dreams of endless expansion," said Stephen Kretzmann, executive director at Oil Change International.

"As the world's fifth-largest economy and home to substantial fossil fuel extraction, California has a responsibility to model a just transition away from fossil fuels in line with the scale of action needed to address our climate crisis," Kretzmann said. "Phasing out existing extraction that's too close to communities, stopping all new permits that expand drilling, and investing adequate resources to ensure nobody is left behind in the transition to a renewable economy are critical next steps."

Oil Change International and other groups emphasized, however, that a full ban on fracking is needed.

"Since Governor Newsom took office, thousands of new drilling permits have been issued," said Alexandra Nagy, California state director for Food and Water Action. "We urge Governor Newsom to immediately institute a complete ban on fracking, stop issuing new drilling permits—which have been increasing under his administration—and use his executive authority to protect communities across the state now."

While Tuesday's announcement certainly represents progress, said Nagy, "much more should be done to address oil and gas issues in California."