Renown climate activist and the man behind 350.org, Bill McKibben (pictured), was the guest at the regular monthly meeting of 350 Brooklyn.

Nearly 70 people at the meeting listen intently as the author and inspiration for many talked about the important role played by groups such as  350 Brooklyn.

Bill joined the event wearing a "Th!rd Act" shirt explaining that he had initiated the organization to hopefully engage with the millions of older people from across the nation and have them align with the urgent need to combat climate change. He said the Th!rd Act had been "a lot of fun".

Enjoy "Music for a Warming World".