21 September 201917.21 "Yesterday millions of people around the world, especially young people, marched and asked for real action on the climate, we showed that we are united and that we young people are unstoppable". So the very young Swedish activist Greta Thunberg started the New York global climate summit at the UN. Next to her is the UN Secretary General Guterres. Greta was greeted by an ovation at the Glass Palace. Greta will also be speaking next Monday in the general assembly hall: "I hope this is a success," he said