Canada must be a leader of climate change, ... It's important for us, for our north, for our role in the world.

We know that climate change is the single most important environmental issue facing the world today. ... The longer we wait the larger will be the challenge,

Global climate change is one of the most significant challenges humankind has ever faced. These landmark exhibitions bring us closer to the science that provides the foundation for understanding how the Earth has changed through time. The exhibitions also convey the human dimension that must be considered in addressing how to respond to the environmental changes that are taking place not just in the Arctic, but all over the globe.

You couldn't necessarily say, 'That hurricane, that storm, that flood only happened because of climate change,' (but) you're starting to see a pattern of extreme weather events.

Bush agreed in Gleneagles that climate change was urgent.

Climate change is, in my view, long term, the single biggest issue that we face,