the summit together with a peoples climate march in which the secretarygeneral participated demonstrated the power of civil society and business as catalysts for national action the close of the summit brought renewed hope not only that a universal agreement might be possible in but also that the highlevel engagement of leaders civil society and business would help galvanize it among its conclusions the ipcc again found that human influence on the climate system was clear it stated that anthropogenic ghg emissions were the highest in history and that recent climate change had widespread impacts on human and natural systems ar emphasized that climate change risk would more severely impact already vulnerable and marginalized communities limiting global warming to c would require substantial emission reductions over the next few decades and near zero emissions of c and other longlived ghgs by the end of the century in addition ar indicated that effective mitigation would require international cooperation