NEW YORK – Around the world, institutional investors – including pension funds, insurance companies, philanthropic endowments, and universities – are grappling with the question of whether to divest from oil, gas, and coal companies. The reason, of course, is climate change: unless fossil-fuel consumption is cut sharply – and phased out entirely by around 2070, in favor of zero-carbon energy such as solar power – the world will suffer unacceptable risks from human-induced global warming.