"Today we're seeing that climate change is about more than a few unseasonably mild winters or hot summers. It's about the chain of natural catastrophes and devastating weather patterns that global warming is beginning to set off around the world."

Barack Obama

"The warnings about global warming have been extremely clear for a long time. We are facing a global climate crisis. It is deepening. We are entering a period of consequences."

Al Gore

"We simply must do everything we can in our power to slow down global warming before it is too late. The science is clear.The global warming debate is over."

Arnold Schwarzenegger

"Global warming is too serious for the world any longer to ignore its danger or split into opposing factions on it."

Tony Blair 

"People tend to focus on the here and now. The problem is that, once global warming is something that most people can feel in the course of their daily lives, it will be too late to prevent much larger, potentially catastrophic changes."

Elizabeth Kolbert