This past Sunday, 400,000 people took part in the People’s Climate March in New York City to demand action on climate change. The march made the front page of The New York Times, but received the usual mix of coverage and inattention that climate activists have come to expect from traditional news media. The same day, there was a second climate march- one that made its own coverage. It was a digital march that engaged participants across the globe on the new battleground for change: social media.