I attended the climate talks in Copenhagen in 2009, and back then, national governments waited until days before to submit climate plans, and the U.S. based its pledge on a proposed bill that would fail in the Senate.

The Keystone XL pipeline is a threat to our nation. It would increase pollution and intensify climate change for generations to come. We must raise our voices and demand our leaders reject this dirty scheme.

When climate change supercharges weather patterns, the disadvantaged often suffer first and most.

We must not sacrifice one of our remaining untamed places in reckless pursuit of oil. We know we have to leave oil in the ground, or destructive climate change will become unstoppable. If not in the pristine and vulnerable Arctic Ocean, then where?

I have long understood that climate change is not only an environmental issue - it is a humanitarian, economic, health, and justice issue as well.

The single most important thing we can do to protect our communities from climate change is to reduce dangerous carbon pollution.