Appalled by government apathy regarding climate change, 15-year-old Swedish activist Greta Thunberg started a protest in front of her country's parliament building in August 2018. She criticized leaders for not doing enough to reduce carbon emissions and stood outside with the sign Skolstrejk för klimatet (school strike for the climate). Within months, Thunberg's strikes and blunt speeches to world leaders and all adults ignited a global movement, inspiring millions of people to take action worldwide.