The world must choose hope over surrender in the fight against climate change, U.N. secretary-general Antonio Guterres said on Monday, warning a summit in Madrid that governments risked sleepwalking past a point of no return. Two weeks of talks aimed at bolstering the 2015 Paris Agreement to curb global warming began against a backdrop of unusually severe weather disasters this year, from fires in the Arctic, Amazon and Australia to intense tropical hurricanes. Guterres, a former Portuguese prime minister and leading advocate of more ambitious action to reverse the upward march of greenhouse gas emissions, urged governments to avoid a “path of surrender” that would endanger the health and safety of all.