STEVE INSKEEP, HOST:
One of the hardest parts of attacking climate change is to imagine a solution. Sure, people know generally what to do - stop putting carbon in the atmosphere. But it's tough to envision how when the world largely runs on fossil fuels. The problem is so central that when Democrats recently proposed a Green New Deal, Representative Alexandria Ocasio-Cortez told us a big goal was simply to rediscover the power of public imagination.
Some experts are trying to imagine the future. So what would a carbon-neutral world look like? NPR's Dan Charles has been asking and today explores the idea of a carbon-neutral city.
DAN CHARLES, BYLINE: I'm taking a walk through downtown Toronto in Canada with the city's former chief planner, Jennifer Keesmaat, and I see somebody waving at us.
Do you know that person?
JENNIFER KEESMAAT: No, but I ran for mayor. So people...
CHARLES: (Laughter) Oh, people...
KEESMAAT: ...People wave at me a lot, and I like to be polite and wave back (laughter).
CHARLES: Keesmaat is taking me to see one particular street here, King Street, where she says we'll see a zero-carbon world taking shape. King Street has a little bit of everything - glass-walled office buildings, theaters, old brick warehouses. Two years ago, a new set of traffic rules went into effect here.
KEESMAAT: Basically, what we've done is we've limited through traffic for cars.
CHARLES: It forced cars away from King Street, which meant the streetcars that run down the middle of the street weren't stuck in traffic anymore. They became the best way to get across town at rush hour.
KEESMAAT: The volume of people being moved is astronomical.
CHARLES: And they weren't burning any gas to do it. Meanwhile, thousands of people've been moving into this neighborhood, buying condos, renting apartments, including the father of one of Keesmaat's friends.
KEESMAAT: He said to me a few weeks ago he thinks he takes out his car about once every two weeks.
CHARLES: He walks to shops, restaurants, basketball games. His neighbors walk to their jobs in the financial district right down the street. And by the way, he's not heating a big, freestanding house anymore. He is using so much less energy. He's cut his greenhouse emissions dramatically.
KEESMAAT: That wasn't the driver for him. He didn't say, how do I in fact live smaller?
CHARLES: It just happened naturally in this new urban geography. For a city planner like Keesmaat, this is totally inspiring.
KEESMAAT: When we provide people with real choices, better choices, it can open up our minds. We can change our minds about what we thought was the only way to live.
CHARLES: So Keesmaat and I are going to imagine it is 2050, and we have stopped climate change. Greenhouse emissions have dropped to zero. We have done it. And cities all over the world look something like this, lots of people living close together within walking distance of things they need. And it's like Keesmaat really sees this world.
KEESMAAT: The vast majority of streets have been completely pedestrianized because that's how people get around, is by walking down the street.
CHARLES: What has happened to the sprawling suburban neighborhoods in this city? Are those houses still there? Are people still living there? How are they getting around?
KEESMAAT: Some of the really large homes haven't actually changed at all. They've just been turned into multi-family units.
CHARLES: Other freestanding houses that lined suburban cul-de-sacs have disappeared. Each one's been replaced with a building that contains five or six homes. Cars have mostly disappeared too.
KEESMAAT: There are cars, but people don't own cars because a car is something that you use on occasion when you need it.
DANIEL HOORNWEG: 2050 is - it's a wonderful life.
CHARLES: This is Daniel Hoornweg, another one of my guides to this zero-carbon world. He's a professor of energy systems at the University of Ontario Institute of Technology. Years ago he wrote a big report on cities and climate change for the World Bank.
Local governments drove this urban transformation, he says. They made the zero-carbon world of 2050 possible. First, they gave people great new ways to move around - electric streetcars and buses. They go to every corner of the city now, and you rarely have to wait more than a couple of minutes to catch one. But also, cities reclaimed that precious real estate we call roads. They started charging for the right to drive on them.
HOORNWEG: One of the things that got us here, probably the most powerful thing that got us here, is we got the pricing right.
CHARLES: The higher the demand to use the roads, the higher the price.
HOORNWEG: So you want an autonomous vehicle? Bless your heart. But it costs you more to drive that autonomous vehicle on the road by yourself. If you ride share, it's a little bit less.
CHARLES: And this is even if they're electric vehicles.
HOORNWEG: Even more if they're electric vehicles.
CHARLES: For one thing, electricity's precious. You can't waste it by powering everybody's individual car. But also, too many electric cars would just clog the streets the way gas-burning cars did back in 2019. That space has to be clear for buses and street cars. This basic recipe's the same for cities all over the world, Hoornweg says - densely populated neighborhoods, mass transit. But the details came from constant experimentation.
If an idea worked in one place, other cities snatched it up. For instance, the city Curitiba in Brazil built dedicated roads for fast buses, kind of like a train system running on wheels, way back in 1991. Now it's everywhere. And it wasn't just technology, Hoornweg says. Over the past three decades from 2020 to 2050, there was a huge cultural shift. Just one example - in Toronto, the sharing economy that started with Uber and Airbnb, it's almost second nature now.
HOORNWEG: Sharing rides, sharing tools, sharing somebody to look after your dog when you're not there.
CHARLES: Yes. Yes, we still have dogs in 2050. In part, we're forced to share things. Cars are rare. Homes are small, but the new city also makes it easier. We're living closer together. We run into each other all the time.
HOORNWEG: We have more acquaintances, somebody we met in our ride pool or carpool or whatever.
CHARLES: Getting to know your neighbors.
HOORNWEG: Yes, and there's no better place to get to meet them than sitting in a car, and you can't get away from them for 20 minutes.
CHARLES: Some people hated this at first. Some liked it. Eventually, Hoornweg says, people just adapted, got used to it. Now, in 2050, life goes on as it always did, with one huge difference - global warming is ending. Dan Charles, NPR News.
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