World leaders tackle climate change at COP25 summit World leaders are meeting at a major climate summit in Madrid to tackle rising temperatures around the globe. The United Nations' COP25 summit will last for two weeks. U.N. Secretary-General António Guterres has called attention to the growing problem, saying "the point of no return is no longer over the horizon." Zack Colman, a climate and energy reporter for Politico, joined CBSN to discuss.