The global fight against climate change is accelerating and reaching a tipping point after a slow start, said Al Gore, former U.S. vice president and co-founder of Generation Investment Management.

“From the time the scientists started sounding the alarm, we’ve waited way too long,” Gore said. “But I’m very optimistic that we’re crossing the political tipping point right now.”

A combination of climate catastrophes such as fires and floods over the past few months have raised awareness among citizens in all latitudes about the need to act urgently against the fast warming of the planet, Gore said. At the same time, the sharp decline in the costs of clean technologies like wind and solar energy, and the outlook for electric vehicles are helping create momentum.

“We’re in the early stages of a revolution that has the magnitude of the industrial revolution,” he said. “Many are saying it’s the biggest investment opportunity of all history.”

In the past, financial firms looking to take advantage of the trend have sometimes made green promises they didn’t keep, or tried to make polluting initiatives look clean for the environment, a phenomenon known as greenwashing, he said.

“ESG investing has become mainstream and there is too much greenwashing,” Gore said. “But this is different now because we’ve seen the rise of public demands to get on with this.”

This article was provided by Bloomberg News.