In the early hours of Sunday morning, bleary-eyed dealmakers from nearly 200 countries and the European Union set a framework for an agreement that would take an unprecedented approach to slowing climate change. Critically, however, they also delayed a host of decisions until next year, which could make reaching a landmark pact even more difficult.With a large rally in New York to complement it, the United Nations held a Climate Summit in September. Tara explains what the gathering was really all about.