AFP / Getty Images An aerial view of buildings standing out amid haze engulfing Wuhan, central China's Hubei province on December 3, 2009.

One time in an airport, when a man noticed I was reading Hot: Living Through The Next Fifty Years on Earth, he leaned over and said conspiratorially, “You know that is alarmist bullshit.”

I asked, “Do you think the world’s weather is changing?”

“The changes are part of a natural cycle. CO2 doesn’t heat up the atmosphere. The sun heats the earth,” he replied.

When I asked him what he thought would happen in the next centuries, he said, “I think the sun will cool back down and everything will work out fine in the end.” I respectfully disagreed with him and quickly left to buy a sandwich.

I’ve learned not to argue too long with people who do not “believe in” human-made climate change. I figure it’s impossible to reason someone out of a position that they didn’t reason themselves into. But the fact is that even those of us who do believe climate change is man-made are in partial denial about our enormous global problems, and almost all of us minimize or normalize the situation.

(MORE: Sorry, A TIME Magazine Cover Did Not Predict A Coming Ice Age)

Our denial is understandable. Our species is not equipped to respond to the threats posed by global warming. Humans are built to find food and shelter, reproduce, and enjoy each other. We are genetically programmed to react to threats by fleeing or fighting, and at first, our environmental crisis does not seem to allow us to do either. We’re better at dealing with problems that are concrete, close-at-hand, familiar and require skills and tools that we already possess. Our global storm is invisible, unprecedented, drawn out, and caused by all of us. We have Paleolithic arousal systems, Neolithic brains, medieval institutions and 21st century technology—not a good mix for solving our climate problems.

And so we feel paralyzed and our belief that we are powerless can become a self-fulfilling prophecy. In a crisis that seems impossible to confront and but too scary to ignore, many people live in a state that psychologist Stanley Cohen calls “willful ignorance.” We both know and don’t know what is going on.

But to state the obvious, we cannot solve a problem we will not face. Gregory Bateson said, “The unit of survival is the organism and its environment.” Our survival depends on our ability to acknowledge, discuss and deal with reality. Once we face our situation, we can progress through a healing cycle that moves from awareness to action. And action, especially in collaboration with others, can be an antidote to despair.

(MORE: Climate Changes Could Make Hurricanes Stronger—and More Frequent)

When problems seem too big for us, the solution is to grow bigger. Of course, we will always have some climate change deniers, but more and more of us are realizing that we will all survive or none of us will. This past February, on a cold and windy day in Washington, D.C., 40,000 people gathered in the largest environmental action in our nation’s history. Of course, even with out collective action, we don’t know for sure what will happen to our planet. But we do know what will happen to us when we act. We will feel more vibrant, empowered and connection. And we will be more hopeful, because hope comes from acting in meaningful ways towards goals we most value.