One by one, the descendants of John D Rockefeller, the Gilded Age oil baron, are repudiating the fossil fuels that made the family rich.  On the heels of the Rockefeller Brothers Fund in 2014, the Rockefeller Family Fund, the charitable vehicle of another arm of the family, announced last month that it would be divesting its shares in coal producers and oil and gas explorers, including ExxonMobil, the modern descendent of their patriarch’s monopolistic money machine, Standard Oil.  “While the global community works to eliminate the use of fossil fuels, it makes little sense — financially or ethically — to continue holding investments in these companies,” the Family Fund’s trustees wrote. “There is no sane rationale for companies to continue to explore for new sources of hydrocarbons.”  The Family Fund has long campaigned for green energy and against carbon emissions, so its fossil fuel investments certainly did not make sense ethically, but financially.  Notwithstanding the terrible recent performance of energy companies during the oil price rout, like it or not, the world still relies on them turning today’s oil and gas reserves into tomorrow’s fuels. On the other hand, the international agreements reached in Paris last year indicate that governments everywhere are stepping up their efforts to reduce carbon emissions, in ways that obviously pose a long-term threat to fossil fuel companies.  In that environment, little wonder that assessing climate change risk has become a preoccupation of the investment community, even among institutions that are not persuaded by the moral case for divestment.