Meet the man living alone in the mountains whose hobby of measuring snowfall led to a global understanding of climate change in this nonfiction picture book from celebrated mother-son team Jonah and Jeanette Winter.

When billy barr came to the mountains as a young man, his only companions were a skunk and a pine marten. He needed something to fill the hours. So he began measuring the snow that fell. Day after day, and year after year, he measured.

As he grew older, he noticed something: the snow was disappearing. It arrived later, melted sooner, and there wasn’t as much of it. He shared his records with a local scientist, who shared them with other scientists, until his measurements were used by scientists all over the world studying climate change. Thanks to his curiosity, groundbreaking data was gathered that still helps us today!