This TED Talk features climate columnist and author David Wallace Wells, recorded live at We the Future 2019.

I'm here to talk about climate change, but I'm not really an environmentalist.

In fact, I've never really thought of myself as a nature person.

I've never gone camping, never gone hiking, never even owned a pet.

I've lived my whole life in cities, actually just one city.

And while I like to take trips to visit nature, I always thought it was something that was happening elsewhere, far away, with all of modern life, a fortress against its forces.

In other words, like just about everybody I knew, I lived my life complacent and diluted about the threat

from global warming, which I took to be happening slowly, happening at a distance,

and representing only a modest threat to the way that I lived.

In each of these ways, I was very, very wrong.

Now, most people, if they were telling you about climate change,

will tell you a story about the future.

If I was doing that, I would say,

according to the UN, if we don't change course,

by the end of the century, we're likely to get about 4 degrees Celsius of warming.

That would mean, some scientists believe,

twice as much war, half as much food.

A global GDP, possibly 20% smaller than it would be without climate change.

That's an impact that's deeper than the Great Depression, and it would be permanent.

But the impacts are actually happening a lot faster than 2100.

By just 2050, it's estimated many of the biggest cities in South Asia and the Middle East

will be almost literally unlivably hot in summer.

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