Since 1998, when Toronto and the surrounding municipalities were amalgamated into a single City of Toronto, we’ve only had four mayors.

Mel Lastman (two terms), David Miller (two terms), Rob Ford (one) and John Tory — still in his first.

Miller was, and remains, megacity Toronto’s progressive mayor. And since leaving his post, he’s continued his passion projects — livable cities and environmental sustainability — in roles for WWF-Canada, the World Bank, and C40 Cities Climate Leadership Group.

After chairing C40 from 2008 to 2010, Miller returned at the end of last year as North American director.

The international organization is a network of more than 90 global megacities committed to battling climate change where the rubber hits in road, in the world’s urban centres. Added together, C40 cities represent more than 650 million global citizens.

Miller recently chatted with Toronto Storeys on how cities can lead on climate change, why our hot summers are worse than our cold winters — and his love letter to Toronto.

So what is something cities can do, that provincial, state or federal governments can’t do?

I think the very significant difference between city governments and provincial, state or national governments, is that city governments are about real action that affects real people’s daily lives.

And the beauty of taking action on climate change is that not only is it the right thing to do, but you end up with an incredible synergy.

It’s the same government that does the right thing to mitigate climate change. For example, having better public transit, having more efficient buildings, dealing with its waste properly, creating sources of green electricity — but you’re also building a better city for people to live in.

And that’s very different than what a provincial or federal government, even a supportive one, is able to do.

They can certainly set good policy frameworks — things like cap and trade, and carbon tax are really important — but it’s in cities that the real actions are happening.

And when they’re done right, they’re also answering residents’ demands for a better place to live.

Aren’t cities usually cash-strapped? Or do some of these initiatives not cost that much money?

Cities have a structural financial issue.

It’s not so much that they’re cash-strapped, it’s that sources of revenues of most cities are made from the property tax, which is a quite inflexible tax — at least in the way it’s run in Canada. It doesn’t grow with economic growth.

So, by definition, the economy in Toronto could be 10 per cent larger in 2019 than 2018. And by definition, except for new buildings, the amount of property tax that the city brings in is the same.

Whereas federal and provincial governments — because they have income taxes and sales tax  (if the economy is growing) — they are bringing in much more revenue. It’s just a different system.

That’s the first problem.

The second problem is that the way the system’s set up, about 94 per cent of the revenue goes to federal and provincial governments, not to cities. They only get about six per cent. It depends on the province.

In that context, it makes things like building a rapid transit network in old neighbourhoods in the city impossible without federal and provincial participation.

But it doesn’t prevent cities doing things like setting building codes, working with local utilities on energy-efficiency initiatives, dealing with its waste in a way that minimizes methane emissions and that in fact makes money for the city, buying electric buses ...

There are all sorts of things a city can do that are within its normal responsibilities, that when added together, make a really significant difference to the amount of greenhouse gas emissions.

And there’s something else that is subtle but really important.

We now have a government in Canada that’s showing leadership, and a government in Ontario and Alberta and British Columbia and Quebec. But that wasn’t always true. The first leadership came from mayors. And that’s been exceptionally important because combined with the ability to actually act, it’s shown a real path forward. And that matters to people.

People want to be able to see that acting against climate change is real and possible. And that’s what the leadership of cities has shown.

Among the C40 cities, how is Toronto faring compared to its peers?

Toronto has done a superb job. And the beauty of Toronto is that it’s just quietly doing the work. And that’s just the way we do so many things in Canada.

In order to address greenhouse gases in cities, you have to address how we heat and cool buildings, transportation, how we handle our waste and how we generate our electricity.

Toronto is addressing all of those. And today emissions are something like 24 per cent below 1990 levels — starting from a strategy that began in 2007, and the closing of the Lakeview coal-powered plant by the province.

And what Toronto has done is a variety of initiatives to produce more efficient buildings, to set higher standards for new buildings, to lower emissions in transportation ...

For example, buying only hybrid buses for the TTC, and in the future hopefully electric. We significantly increased transit service — although it was repealed under my successor, but it’s been brought back now.

And it’s doing very well with its methane emissions from landfills.

In fact, there’s a new plant scheduled to open that will produce enough cleaned methane — which becomes natural gas — instead of just emitting the methane in the atmosphere. It’s a very bad greenhouse gas, but (cleaned methane) could be used to power the entire fleet of garbage trucks in Toronto. So a very closed-loop system.

Lots of cities are showing great leadership: San Francisco, Los Angeles ... New York City has a very advanced climate plan. But the thing about Toronto is it understands that you have to do a little bit of everything. And that’s what Toronto’s plans are doing.

And I think the other important thing that we’re seeing in more and more cities — New York and Los Angeles are good examples — they understand that you can’t address climate change without addressing social equity and injustice. Because the impact of environmental issues, the negative impact, is often on those least well-off.

There’s a number of examples in both New York and Los Angeles, initiatives that have included low-income communities and tried to meet their needs. So solutions for climate change are also creating local employment, cleaning local communities, and helping those communities become more resilient — economically and socially, as well as environmentally.

I’m glad you bring that up — injustice and social equity — because I feel like sustainability issues don’t generate the same sort of heat and outrage as other issues, such as race or gender. And I wondered if that was because there isn’t a "human face" on sustainability issues.

The problem is so large. It’s very difficult to know what your part as a citizen is in providing a solution.

And that’s why I think mayoral leadership is important because its programs and policies come down to real concrete things — sometimes literally concrete things — that people can see and understand, and see themselves as a part of the solution.

There’s a different reaction, I find, when people are talking about how environmental issues affect their local neighbourhoods — air quality issues, water quality issues, overuse of pesticides, those kinds of things.

People have a very direct reaction to them. And I think that’s one of the reasons that, going forward, advocates about climate change are going to need to ensure that people are included as part of the solution.

So that’s why I mentioned New York and Los Angeles. Those initiatives that start with including people from low-income communities in the conversation.

In New York, as well as (the Hurricane Sandy area), it’s really coming out of resilience. In Los Angeles, it’s more from local environmental issues, like air pollution and higher rates of asthma in low-income communities.

Working with people on those kinds of issues is a way to connect them to the bigger issue of climate change, and demonstrate that action on climate can help address the local issues. Done the right way, it can help meet some of their local needs, particularly the need for decent, local employment.

So we’re in a heat wave in Toronto right now. How are you cooling your house?

That’s a very good question. And a fair one.

When it gets scorchingly hot, we have air conditioning. When it’s anything less than scorchingly hot, we try to be an open-window house. We’re on Bullfrog Power, which gets us both clean natural gas and clean electricity.

But it’s a really good question for me because one of the big issues in the electricity system in Canada is not cold winter days — it’s hot summer days.

And for a long time, coal-fired power plants were justified on the basis that you need them for peaking in the summer.

It’s a good example of why we need to find far better ways to ensure our homes, offices and other buildings are extremely energy-efficient. The leadership shown by cities on energy-efficiency issues is going to be more and more important as we start to see longer and hotter summers.

We’re going to see more and more of these kinds of heat waves in climates like Toronto’s. So it’s very critical that the issue gets a lot of attention.

I saw a report that the number of air conditioners worldwide will rise from 1.6 billion now to 5.6 billion by mid-century, which is going to make the world even hotter. So as it becomes more punishing outside, we’re going to have to seek more refuge inside. And we’ll be blasting these machines — and just making it worse. Just accelerating it.

It’s a real worry. And there’s an initiative in Toronto called Power Renewal.

It’s very important in this context because the concrete apartments buildings built in the '60s and '70s are highly inefficient. And if we can find ways — and there are ways — to significantly increase their energy-efficiency, then you combat the need for air conditioners.

If you go to China and see the buildings there, you understand their challenges with climate change. [When you see] how they’re heated and cooled, it really makes you worry. Because there are just air conditioners hanging off every window. It’s not sustainable economically and socially, let alone environmentally.

[Editor’s note: Coincidentally, that is the exact image used in this New York Times’ article about air-conditioning units.]

Is there anything you miss about being mayor?

Well, everything.

Really, you loved it? All of it?

I loved every second of it. It was an absolute privilege.

I had been involved in municipal politics for 20 years. People just sort of saw the last seven. They didn’t realize that I’d been involved for a long time before that. And I had done everything in the big picture that I had set out to do.

I really felt that I didn’t want to be the kind of politician that tried to hang onto power just to keep power. I was a mission-driven politician and the initiatives that I deeply cared about were well underway, or even completely embedded. In fact, they’re still driving city policy eight years later.

So, for me, it was the right time to step away. But I loved all of it.

The best thing for me was the people of Toronto.

They never let me down. They really wanted their city to move forward. And I think that’s why they chose a progressive mayor in 2003.

It was a time when people wanted to step forward as a real leader in the 21st century, and that’s exactly what we did.

So every second was a privilege.

This interview has been lightly edited for length and clarity.