This weekend, more than 300,000 people marched on midtown Manhattan in what’s being called “the largest mobilization against climate change in the history of the planet.” Celebrities (including Leonardo DiCaprio and Mark Ruffalo), political leaders (including UN Secretary General Ban Ki-moon and former Vice President Al Gore) and people who were bussed in from cities around the country took part in the People’s Climate March, a massive effort to persuade world leaders to take more dramatic action to fight climate change. This week, global political leaders will gather at a UN summit and discuss measures and new agreements that will be put in place to combat climate change. In a statement, Ban Ki-moon said, “While marching with the people, I felt that I had become a secretary-general of the people. There is no Plan B because we do not have a planet B. We have to work and galvanize our action” …