Agence France-Presse: Leaders of 40 of the world’s major cities pledged action Thursday to fight climate change, taking measures ranging from promoting solar energy to tracking genetically modified food. Warning that crowded urban areas were especially susceptible to the planet’s rising temperatures, city officials said they needed to take the lead in adapting to climate change. “Very important actions are taking place by mayors who act,” Toronto Mayor David Miller, the chairman of the so-called C40 …