It's the Brian Marrishow on WNYC. Good morning again, everyone. We'll take a break now from discussing the Democrats' campaign transition. We will come back to it for a call-in and any more developments for our last

segment this morning. But now we continue our WNYC Centennial series, 100 years of 100 things.

We're up to Thing 5, which is very relevant to the presidential campaign. It's 100 years of global

warming at a time when we've got a pro-warming party

and an anti-warming party and another way to put, or another way to put it, a do-something

versus a no-climate policy party. Judging from the Republican Convention and speeches and the

written party platform, they are doubling down on a no-climate policy approach as a

centerpiece of their populism. But for this 100-year segment, I've got the temperature data here

with a very revealing curve of what exactly has changed globally and locally in our temperature

patterns since 1924. And with us to help explain the very big picture is Michael Mann,

Professor of Earth and Environmental Science at the University of Pennsylvania, with a secondary

appointment in the Annenberg School for Communication, a very interesting combination. And as such,

he is also director of the Penn Center for Science, Sustainability, and the Media.

And Michael Mann is the author of several books, including his latest, perfect for the series,

Our Fragile Moment, How Lessons from the Earth's Past, can help us survive the climate crisis.

Professor Mann, it's great to have you for this. Welcome to WNYC.

Thanks, Brian. It's great to be with you. And considering what's in your book, we might

have to retitle this segment instead of 100 years of 100 things. It might have to be 100 million

years or 4.5 billion years. So how far back do you go in tracing the warming and cooling periods

of the Earth's history? Yeah, well, you know, more than 4 billion years, and life has been around on this planet

for the better part of that 4 billion years, at least 3.8 billion years ago.

And so the purpose of this book was really to take the numerous lessons that Earth's history has to offer us when it comes to the obvious

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