Did you know choosing the train over your car can cut your carbon footprint by up to two thirds?

So, one family outing at a time, one little adventurer at a time, one trip to the museum, one dinner in the city, one nap on the way home at a time.

One train journey at a time can help create a greener future.

So when will you take your next trip? Find out more at nationalrail.co.uk slash greener.

A few weeks back, I scheduled a conversation with Abram Lustgarten, a reporter with ProPublica.

I wanted to talk to him about his reporting on climate migration, when climate change forces people to move, how many leave their homes, and where they go.

Through his reporting, Abram is deeply familiar with the topic, but his experience doesn't end there.

He lives in the Bay Area of California, and the day before we were supposed to speak, he and his family had to flee the wildfires closing in on the city.

We had to reschedule.

When I finally got him on the phone, I wondered if his work on climate change affects the way he views the blazes in his state.

Have you thought about moving? I mean, you're there in the middle of a wildfire. Have you thought about living elsewhere?

Yeah, you know, I have to confess, I think, about it every day, and as we're sort of burning here in the burning season, every fall, that question becomes more and more important.

You go back to the beginning of time, and you see that environment has driven the movement of populations.

So there's research connecting the earliest migrations out of Africa towards Europe to a drying trend and a drought in the South and progression along kind of a green belt that led people north.

The drought that ultimately decimated the Mayan civilization in Central America is another great example, and there's research that suggests that the Mayan people tried to adapt and migrate away basically outrun the environmental change that was happening there but failed.

But the scale of what we're headed for is unlike anything that has ever happened in the past.

Predicting human behavior is incredibly difficult and notoriously imprecise, but understanding how the changing climate might also change population density around the world is crucial.

When populations move in large numbers within their countries, then across international borders, the effects of that movement can echo across the globe from scarcity to political unrest to violence.

Those consequences are tied to the number of people that will eventually have to move.

So predicting the scale of climate migration has been a two year obsession for a brawm and his colleagues.

That really became kind of the holy grail for us was to see if there was any way to collect enough data about who lives where and how environmental conditions are changing to be able to create almost an artificial intelligence model that could predict where they would begin to go.

The result of their work is a step towards that holy grail and all they needed was a supercomputer and billions of data points.

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