Hi, this is Penn Badgley. I'm doing a little guest hosting today. If you want to learn how to take real, lasting climate action, like I do, I want to invite you to join Countdown. Ted's new global initiative to accelerate solutions to the climate crisis. One great thing about taking a posture of learning together is that we discover what's

possible and impossible.

So it's an opportunity to become excited and hopeful about the future for humanity.

Now, here's a talk from the Countdown Global Launch event given by Prince William, the Duke of Cambridge.

To hear more of these ideas and get involved, check out countdown.com and subscribe to the

countdown podcast wherever you get your podcasts.

Hello everyone. Growing up in my family gives you a certain sense of history.

I'm simply the latest in a line that can be traced back generations.

This oak tree is close to Windsor Castle,

which has been home to my family for over 900 years.

39 monarchs have lived here and enjoyed these beautiful surroundings.

I've walked here many times myself, and it always amazes me that some of the trees planted here,

living organisms dependent on soil, rain and sunlight, were here as they laid the first stones of Windsor Castle.

That makes some of the oaks here almost a thousand years old.

These trees germinated during the reign of William the Conqueror in 1066,

from a simple acorn.

By the time that Henry VIII lived here,

they'd grown into mature, impressive giants.

And amazingly, some of those very same trees still survive here today.

They're a bit gnarled and hollowed out, but they're still very much alive.

While these oaks have been growing, around 35 billion people have lived their lives on our planet.

That's 35 billion lifetimes worth of hope, love, fear and dreams.

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