Climate change is going to require collective action, but how can individual actions make a difference?

On a new episode of LifeKit, we're walking you through what sort of climate-friendly choices can make an impact in your life and the lives of others.

Listen to LifeKit, part of NPR's Climate Week, wherever you get your podcasts.

All and Nancy, do you remember me? I could never forget you. Thank you.

Dear Ma, thank you is how every letter I write to you should begin.

My dear son, love, you taught me what that was.

Dear Asifa, I wanted to let you know that when I think about you, I remember your hand holding my hand, which was shaking that day.

I remember your smile throughout the day. It's like I had known you forever.

How can we focus on the things we're most thankful for? What are the best ways to express our gratitude?

I'm Dacker Keltner, welcome to the Science of Happiness. On each episode of our show, we have a guest try a science-backed method to bring more happiness into their life.

And over the years we've looked at various ways to cultivate gratitude, like writing someone a letter or journaling about what we're thankful for each day.

People who practice gratitude feel less depressed, more optimistic about life, and they have stronger relationships.

There's also a host of health benefits which we'll hear about more later on in the show.

Let's start with one of my favorite ways to practice gratitude, writing a gratitude letter to someone we want to thank.

All and Nancy, do you remember me? I could never forget you.

Judy Morales is an award-winning children's book author. When she came to the United States from Mexico, she spoke no English but found a friend in Nancy, the local librarian.

True at first I might have been a scare of you, guardian at your desk, and too close to the basket of baby books that my son always walked towards when we entered this unbelievable place.

The children's book section of the Western Addition Public Library.

Judy wrote a gratitude letter for Nancy and shared it with us on our show.

Nancy was, I mean, she probably doesn't know about how important she is in my life.

She allowed me to feel that what the library has to do was for me too.

It wasn't only for the people who was born here in the United States.

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