"I have been protesting outside the Swedish parliament every Friday to pressure the government to comply with the Paris agreement." Sixteen year old Greta Thunberg has drawn international attention to her fight against climate change. Since she was 11, Greta battled with depression at what she saw as global inaction on climate change. "I was diagnosed with Aspergers, OCD and selective mutism", she explains. She has now reached her 21st strike from school and inspired children all over the world to follow her. "She's back in normal school; it's like her special needs are gone!", her father says happily. Meanwhile, 68-year-old Billy Barr, who lives in an isolated house at 2,900m altitude in the Rockies, has been measuring snowfall every day for 46 years. "I started writing down the daily weather, and that’s all it was, it was entertaining. But after five years I went back to my notebooks, and compared that winter to all the other winters, and I kept doing that year after year." In 1990 a biologist learned of Billy's data, and it is now crucial to scientists' understanding of the rate at which climate change is occurring. "He’s someone that can convey how the world’s changing...he brings a story that people can connect to personally."