Grantham, who is 72 and has what’s left of a British accent after living in Boston for more than four decades, outlined this wildly distressing assessment against a bland backdrop of chain décor and piped-in smooth jazz. He marked up his draft with a pen as he went along, departing from the text at times to emphasize a point. “Phosphorus makes up 1 percent of your body weight,” he said, looking up from the page to catch my eye. “It’s a basic element, the residue of exploded stars. You can’t just make more.” He also pointed out that most economists see global trade as a win-win proposition, but resource limitation turns it into a win-lose, zero-sum contest. “The faster China grows, the higher grain prices go, the more people in China or India who upgrade to meat, the higher the tendency for Africa to starve,” he said.

Grantham argues that the late-18th-century doomsayer Thomas Malthus pretty much got it right but just had the bad timing to make his predictions about unsustainable population growth on the eve of the hydrocarbon-fueled Industrial Revolution, which “partially removed the barriers to rapid population growth, wealth and scientific progress.” That put off the inevitable for a couple of centuries, but now, ready or not, the age of cheap hydrocarbons is ending. Grantham’s July letter concludes: “We humans have the brains and the means to reach real planetary sustainability. 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.”

Grantham’s quarterly letters, which command a cult following of readers within and beyond the financial industry, inspire even the most short-term profit-minded investors to do a little fate-of-the-world-scale thinking. I find that they have the opposite, equally mind-stretching effect on a passive investor like me. Although I’m normally happy to turn over my paychecks to the missus and not inquire into what happens to them, my encounters with Grantham tend to whip me into a state of alarm that has me thinking about acquiring tracts of arable timbered high ground, preferably defensible ones well inland from the rising seas.

Doomsayers are always plentiful, and the economic and environmental news has encouraged even more doomsaying than usual of late, but Grantham compels attention, in part because he’s not simply prophesying doom. While it may be too late to “gracefully” deal with depleted resources­, climate change and related crises, it’s never too late to mitigate the damage. And, crucially, the consequences will be unevenly distributed, creating angles for you to make money and look out for your interests, however you define them.

“I never think of him as one of the doom-and-gloomers running around like chickens with their heads cut off,” says Barry Ritholtz, the head of the quantitative research firm FusionIQ and a widely read commentator on the financial world. “He’s not telling people to stockpile water and dehydrated food. He’s saying this asset class will underperform or not.” Distinguishing Grantham from other notable big-picture pessimists like Nouriel Roubini and industry skeptics like James Grant, Ritholtz says: “Keep in mind that he has run a lot of money. He’s like a mechanic who’s telling you, ‘Fix this, or you’ll have trouble down the road.’ Then there are all the kibitzers standing around watching the mechanic and offering advice.” Ritholtz likens Grantham to Warren Buffett, another mechanic with advanced rhetorical skills — “only Buffett’s buying companies and Grantham’s looking at asset classes: ‘For the next 10 years, buy commodities.’ ”