Xiye Bastida, 18 year old Otomi-Toltec Climate Activist, wrote and read a moving letter to her grandmother in this TED Talk. Xiye Bastida reflects over her past year working to join the people of New York City and the world in fighting climate change. In a Ted Talk, Greta Thunberg, 18 year old Swedish climate activist, gives her case for why climate change needs immediate action against it.