Every year, tens of millions of salmon return to the pristine shores of Bristol Bay in Alaska. They linger in the bay's cool, shallow waters before charging up nearby streams to spawn and create another generation of wild salmon.

Too often, the air conditioners we use to cool down also contribute to climate change - the very force that's fueling extreme heat.

The science tells us that if we fail to reduce global warming pollution, global temperatures will rise to dangerous levels and unleash devastating extreme weather events and accelerate destructive sea level rise.

The U.S. has a proud history of cleaning up our air through technological innovation. We did it with leaded gas, acid rain and countless other pollutants, and we can do it with carbon pollution, too.

When we go to the store, we bring home more than food - we bring home traces of broader environmental problems. But we can use our shopping carts and dinner plates to help solve some of those problems.

Our nation has abundant clean energy resources, and tapping them will generate jobs, make the air safer to breathe, and tackle climate change - the greatest environmental crisis of our time.

Many environmental battles are won by delaying a destructive project long enough to change the conversation - to allow new economic, political and social dynamics to emerge.

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

Climate change is the central environmental ill of our time. We have an obligation to protect our children from the dangers of this widening scourge, and we aren't yet doing enough about it.

When the government undertakes or approves a major project such as a dam or highway project, it must make sure the project's impacts, environmental and otherwise, are considered. In many cases, NEPA gives the public its only opportunity to be heard about the project's impact on their community.

We can choose food that doesn't lead to illnesses like diabetes and cancer. We can choose food that doesn't contribute to water pollution and climate change. And we can choose food that keeps local economies vibrant and farmers on their land.