Stephen Manley, 67, first learned about the thinning of the atmosphere when he was a college student at the University of Massachusetts Amherst.
"I remember a physics teacher telling us about climate change in the early '70s," he said.
Decades later, Manley started to wonder how his financial investments might be contributing to global warming. So he scrutinized his stock portfolio, and didn’t like what he found.
"Chinese coal, and gas and oil, and drilling equipment," he said. "It bothered me that this money I had in a portfolio was supporting the continuation of the burning of carbon fuels. I don’t want to be invested in that."
Manley called his financial advisor and asked him to pull his investments from the fossil fuel industry.
"And so my conscience is clear and I’m not contributing to the degradation of the planet," he said.
Manley is part of a growing trend of individual investors who are aligning their money with their values.
"The message of investing fossil-fuel-free is really affecting people and really speaking to what they are concerned about," said Leslie Samuelrich, president of Boston investment firm Green Century Funds.
Green Century runs a fossil-fuel-free mutual fund, and in the last year that fund has grown — a lot.
"It’s nearly doubled in the last year," Samuelrich said.
Samuelrich said that big and small investors are joining the fund.
"They don’t want to have the dirty coal," she said. "The high-profile controversial oil, and increasingly, people are becoming really concerned with the reputational and financial risks around hydraulic fracturing called fracking."
And then there are the investors who are influenced by their kids. Tim Greiner started paying more attention to his investments after his son, Casey, joined the divestment movement at Colby College in Maine.
"He comes home at Thanksgiving he talks about it," Greiner said. "He did a rally up in Portland, Maine. They were protesting the opening of a pipeline that runs from Canada into Portland, Maine that could potentially carry tar sands oil, and we went to the protest and there were hundreds of people there."
Afterwards, Greiner and his wife called his financial advisor. They wanted to know if their investments would still yield competitive returns if they divested from the fossil fuel industry.
"My investment advisor confirmed that we weren’t sacrificing very much at all — if anything — by getting out of oil and gas stocks," he said. "That there were plenty of other really solid investments."
Greiner’s investments are now 99 percent fossil-fuel-free, as the fossil-fuel divestment movement continues to grow.