Next week, Pope Francis is scheduled to release "Laudato Sii" ("Praised Be You"), his eagerly anticipated encyclical (authoritative teaching document) on the environment.

I have never seen such excitement -- and controversy -- surrounding an encyclical. It speaks to the extraordinary global presence Francis has achieved in a relatively short period of time. This feels to me like one of those rare moments when the Message and the Messenger can combine to change the world in a very significant way.

Rising sea levels and catastrophic weather events have gotten people's attention. People are becoming more aware of the reality that climate change isn't just a theoretical conjecture, scientific debate or partisan political issue. It's real, it's happening now, and it's dangerous.

And Francis -- uniquely among world leaders -- has the ability to change the conversation around the need to protect our environment.