Climate change may be serious stuff for many of us, but for Al Gore, it's seriously profitable. He's about to become the world's first "carbon" billionaire:
Few people have been as vocal about the urgency of global warming and the need to reinvent the way the world produces and consumes energy as Mr Gore. And few have put as much money behind their advocacy and are as well positioned to profit from this green transformation, if and when it comes.
Critics, mostly on the political right and among global warming sceptics, say Mr. Gore is poised to become the world's first "carbon billionaire," profiteering from government policies he supports that would direct billions of dollars to the business ventures he has invested in.
Representative Marsha Blackburn, Republican of Tennessee, has claimed that Mr Gore stood to benefit personally from the energy and climate policies he was urging Congress to adopt.
Mr Gore had said that he is simply putting his money where his mouth is.