WARSAW, POLAND — The devastation caused by Typhoon Haiyan cast a gloom over U.N. climate talks Monday as the envoy from the Philippines broke down in tears and announced he would fast until a “meaningful outcome is in sight.”

Yeb Sano’s emotional appeal was met with a standing ovation at the start of two-week talks in Warsaw where more than 190 countries will try to lay the groundwork for a new pact to fight global warming.