Climate activist Greta Thunberg photographed on the shore in Lisbon, Portugal December 4, 2019. (Photograph by Evgenia Arbugaeva for TIME)

TIME Magazine named 16-year-old climate activist Greta Thunberg, who is on the autism spectrum, its person of the year for her work encouraging everyone from young people to world leaders to address climate change. Thunberg, who credits autism with helping her to see the world in a unique way and focus for long stretches of time, started her career as an activist in 2018 calling for young people to go on strike from school to raise awareness of climate change.