Charlie Baker’s trip to Washington to talk climate change earlier this year was a story with an irresistible plot: Here was a Republican governor, urging members of his own party to grapple with a threat some of them still don’t believe exists.

“In Massachusetts, climate change is not a partisan issue,” Baker told the House National Resources Committee in February. “While we sometimes disagree on specific policies, we understand the science and know the impacts are real because we’re experiencing them firsthand.”

Soon after, Baker’s D.C. visit was cited in a story published by E&E News, a website focused on energy and the environment, which suggested Baker might actually be America’s strongest climate governor.

Here at home, though, Baker’s legacy on climate remains a work in progress, and the subject of some debate.

When Jack Clarke, the director of public policy and government relations of Mass Audobon, an environmental advocacy group, reviewed Baker’s testimony, he was struck by how much the governor has changed in a relatively short period of time.

In 2010, Clarke recalled, during Baker’s unsuccessful challenge to Democratic Gov. Deval Patrick, he and several other environmental advocates made a visit to Baker’s campaign office. They planned to urge the candidate to take climate change seriously.

Instead, Baker turned the tables and urged them not to.

“[He] decided that he would give us a talk, using a whiteboard, on what climate change was all about,” Clarke said. “I would say he was skeptical. ... His contention was that there were people smarter than he who were informing him otherwise on whether or not, not only was it real, but was it man-made. We went back to our offices and said, you know, we need to educate this guy.”

Since then, Baker has gone from climate change skeptic to true believer. As Clarke sees it, he’s governed accordingly — upping the use of renewable energy sources like wind and hydropower, providing new funding to help cities and towns prepare for coastal flooding, and even suggesting a new tax to help cover the costs of climate adaptation.

“Gov. Baker,” Clarke said, “has far exceeded expectations.”

When Andrea Honore read Baker’s Congressional testimony, though, she had a very different take. For the past two years, Honore has been staging an on-again, off-again lunchtime sit-in in Baker’s office, trying to get him to oppose a new gas compressor station slated for a site in Weymouth.

“I broke my eye roll, honestly,” Honore, a Weymouth resident, said. “Many of us were like, ‘Are you kidding me?’”

She and others argue that the facility, if built, will be a safety risk with adverse local health effects — and note that a majority of the gas it processes will be shipped outside of Massachusetts.

“Over 50 percent of the gas that is slated to run through this is for export to Canada,” Honore said.

For the record, Baker hasn’t endorsed or condemned the Weymouth compressor. Instead, he’s said the state is doing its due diligence — including, recently, making a key regulatory ruling that moves the project closer to fruition — on what’s ultimately a federal issue.

This approach, in turn, points to bigger frustration some environmental advocates have with the governor: While he decries the consequences of climate change, they say, he’s not nearly aggressive enough when it comes to stopping it.

“We know that if we’re going to pass on a safe and healthy and livable planet to our children, we need to get off of fossil fuels as quickly as we possible can,” said Ben Hellerstein, the head of Environment Massachusetts, an environmental advocacy group. “And that’s why it’s been so discouraging to see the governor be such a vocal advocate for expanding fossil-fuel infrastructure like pipelines in our state.”

In 2015, Hellerstein notes, Baker supported an industry-backed plan to fund new pipeline construction through fee hikes on rate payers, a move he said would make the region’s electrical supply more reliable. The Massachusetts Supreme Judicial Court ultimately found that this approach was illegal.

Ideally, Hellerstein argues, Baker should flex his political muscle to push for an aggressive transition to all-renewable energy.

“We’ve actually worked with legislators to file a bill that would get Massachusetts to 100 percent renewable electricity by 2035, and 100 percent renewables for other purposes like heating and transportation by 2045,” Hellerstein said. “The biggest statement that the governor could make in support of climate action would be to throw his support behind those targets."

Also backing that legislation? The Massachusetts Sierra Club, whose director, Deb Pasternak, calls Baker’s climate record mixed.

On the one hand, Pasternak praises Baker’s decision to join a new, regional push to limit transit emissions, calling that move “really exciting.” And, she says, the message Baker brought to Washington earlier this year was crucial.

“The fact is that we do need the federal government to act on climate,” Pasternak said. “The states can’t do this alone.”

But as Baker waits for the feds to heed his call, Pasternak added, he could be making big, meaningful changes to the way Massachusetts thinks about energy use.

“Some states around the country are starting to require climate impacts as part of their evaluation of energy infrastructure projects,” Pasternak said. “New York just declined a pipeline, New York state, based on climate impacts. ... That is exactly what we need.”

Pasternak also argues that, when it comes to climate-related matters, Baker has been the beneficiary of two key pieces of legislation signed into law by Patrick in 2008: the Global Warming Solutions Act, which set strict carbon-emission reduction targets for Massachusetts; and the Green Communities Act, which created a framework to encourage renewable and alternative energy use.

“Baker walked into, actually, a very good situation here in Massachusetts,” she said.

In an emailed statement to WGBH News, a spokesman for the governor wrote: “The Baker-Polito Administration invested over $609 million to address climate change mitigation and adaptation … secured the largest renewable energy procurements in state history … and maintained Massachusetts’ position as the #1 state in the country for energy efficiency.”

Asked for Baker’s position on the aforementioned legislation that would shift Massachusetts to all-renewable energy use by 2045, the spokesman said the governor will “carefully review any legislation that reaches his desk.”