Canada and California are partners in the fight against global warming.

And Canada’s top climate official, Catherine McKenna, hopes the Trump administration doesn’t entirely abandon the cause.

McKenna, minister of Environment and Climate Change, met with Gov. Jerry Brown last month in San Francisco to enlist Canada in Brown’s Under2 Coalition, a collection of 170 nations, states and provinces pledging to keep warming below 2 degrees Celsius. The move could have direct implications for California.

Canadian Prime Minister Justin Trudeau wants each of his country’s provinces to put a price on greenhouse gas emissions. Quebec already does that by participating in California’s cap-and-trade system, and Ontario plans to join next year. Others could follow.

McKenna sat down with The Chronicle to discuss how provinces, states and businesses can address warming, even as the Trump administration threatens to end federal climate efforts. She also had a few words of climate advice for the White House.

This interview has been edited for space and clarity.

Q: Will signing on to the agreement require Canada to do anything beyond what Prime Minister Trudeau has already put forward?

A: We already have a serious climate change plan. It includes putting a price on carbon pollution for any provinces that haven’t already put a price on them. It goes up to (US$37) per metric ton by 2022. We are phasing out coal by 2030. And our plan is to have 90 percent clean electricity by 2030.

In Canada, the provinces have really led the way. With our past federal government, there was a decade of inaction, and we saw provinces like Quebec step up, join the cap-and-trade system with California. The same with Ontario.

Q: For those of us here in the U.S., what lessons can we draw from that experience in Canada? We are now — it looks like — shifting from a period of great action on climate change at the federal level to one where, at best, there will be inaction and at worst there will be attempts to sabotage what we’ve already done. Can we still make progress just working at the sub-national level?

A: Look, I’ve made the case that climate action makes economic sense, that it creates good jobs. If you look at the renewable sector, there’s a significant number of jobs, and there’s a real economic opportunity. And I will continue to make that case with my (American) counterparts at the federal level.

But you know, even without that federal action, you are seeing not only states like California leading the way. The top five states for wind power are, I think, Republican states. [Editor’s note: California ranks fourth among states with installed wind capacity.] Beyond that, you see businesses really stepping up. (Recently), Walmart came out with what they call the gigaton project. So they are going to reduce a gigaton of emissions from their supply chain. That’s equivalent to more than all the emissions from Germany.

Q: Do you think that California is going to get more Canadian provinces joining its cap-and-trade system because of the prime minister’s carbon-pricing initiative?

A: It is really up to provinces to decide which route they go. So 80 percent of Canadians already live in a province where there’s a price on carbon pollution. British Columbia has chosen a revenue-neutral carbon tax. Alberta has a similar approach, with a direct price. So the provinces will have a look at it.

I think, though, that you’re seeing interest from other places, other countries as well. I know Mexico is looking seriously at California. I think there is interest from Chile, I’ve heard. China is coming on with its cap-and-trade system this year. Who knows, maybe they will eventually link with California.

Q: Is it possible for Canada to meet its goals in climate change while still producing the tar sands and encouraging their development?

A: It is important to look at what Alberta’s done. We have a new (provincial) government that came in and took serious action on climate change. For the first time ever, they put a hard cap on emissions from the oil sands: a 100-mega-metric-ton cap. I challenge you to find any other industry where there is a hard cap on emissions. They committed to phasing out coal, and they also put a price on carbon. So they have taken very serious action. And that enabled us to get a plan across Canada to tackle climate change, because we knew that every province needed to be part of it.

Q: Although at the same time, you’re still encouraging some pipeline development as well.

A: Yes, but as I said, what Alberta is doing is part of our climate plan, with a hard cap. We have built that into our climate plan.

And as I explain to folks, we are very serious about climate action — but people need jobs. We are in a transition period. You can’t transition overnight. It’s not possible. We need to be smart about policies so they last. I’ve spent a lot of time working, not just with environmentalists but with industry to look at how do we work together as opposed to fighting.

Q: There is apparently quite a debate going on within the White House about whether or not to stick with the Paris climate accord. If you were to make an argument in favor of it to this administration, what would you say?

A: Look, I think the Paris agreement is a flexible agreement. And so the new administration could take a different approach to it. I also think it’s the economic case — that there is a real economic opportunity to do what we want to do in Canada and what the U.S. administration wants to do, which is to create good jobs for the most number of people, to foster innovation. We are seeing amazing new American companies — like Tesla — that are creating wealth and jobs.

Also, I think that it’s just better to be at the table.