Agence France-Presse: China’s top weather official warned Wednesday that Tibet was threatened by global warming, which could cause floods and droughts endangering millions in the nation’s west, state media reported. “The impact of global warming has accelerated glacial shrinkage, and the melting glaciers have swollen Tibet’s lakes,” Zheng Guoguang, head of the China Meteorological Bureau, was quoted as saying by the official Xinhua news agency. “If the warming continues, millions of people in …