Are green stocks a mega trend or a bubble in the making?

This might suggest that bubble talk is mere hyperbole, but investment analyst Joachim Klement, who describes himself as a fan of ESG investing, says a green bubble may well be forming.
Klement cites research presented at the first conference on the economics of climate change held by the San Francisco Federal Reserve last November, research which focused on the exposure to carbon risk of thousands of listed companies around the world.