74-year-old investor Jeremy Grantham's firm manages more than $100 billion in assets thanks in part to his legendary knack for identifying and profiting from market bubbles. Over the last 15 years, Grantham has been ringing the alarm about the carbon bubble in the atmosphere, whose bursting threatens more than a temporary economic downturn. The former oil analyst entered the energy debate fray in 1997 when he co-founded the Grantham Foundation For the Protection of the Environment, which is to climate change what the Gates Foundation is to malaria. The foundation supports major environmental advocacy organizations from the World Wildlife Fund to the Nature Conservancy, as well as two London climate-research institutes bearing his name. Grantham also uses his widely read newsletter as a platform for warning the investment community about the limits of growth and the looming dead-end of profit-driven, short-term planning. Sometimes he speaks in the language of investment advice, explaining profits will be hard to turn in a future of soaring commodities prices, food scarcity and wild social, climatological and geopolitical instability. Other times, he'll make direct appeals to investors to free their minds, hoping their portfolios will follow. "We humans have the brains and the means to reach real planetary sustainability," wrote Grantham in a 2011 newsletter. "The problem is with us and our focus on short-term growth and profits, which is likely to cause suffering on a vast scale. With foresight and thoughtful planning, this suffering is completely avoidable."
Last year, Grantham took to the pages of the scientific journal Nature to call for bolder public involvement by the scientific community – including acts of civil disobedience resulting in arrest – to counter the climate-denialism machine lavishly funded by his fellow billionaires in the fossil fuel industry. "Scientists are understandably protective of the dignity of science and are horrified by publicity and overstatement," wrote Grantham. "These fears, unfortunately, are not shared by their opponents, which makes for a rather painful one-sided battle. This is not only the crisis of your lives – it is also the crisis of our species' existence."