Agence France-Presse: Tens of thousands of people in London joined a global day of protest Sunday to demand action on climate change, among them British actress Emma Thompson who said the challenge to save the planet was like tackling a Martian invasion. An estimated 40,000 people marched through the British capital, according to the Avaaz campaign group, which said the turnout "massively exceeded our expectations". Police would not give an official figure. The protest was one of thousands across the globe aimed at...