Pete Buttigieg is one of 10 presidential candidates taking part in CNN's climate crisis town hall Wednesday, September 4 at 5:00 p.m. ET. He is the mayor of South Bend, Indiana. The views expressed are his own. View more opinion articles on CNN.

(CNN) When I first became mayor of South Bend, I toured our city's emergency operations. I hoped I'd rarely have to return. But during my time as mayor, we've had to activate it twice just for floods that are supposed to occur once in a millennium.

South Bend isn't alone. From hurricanes devastating Puerto Rico to fires ravaging the Amazon, climate change is affecting everyone, everywhere. It is the security challenge of our time, and a wall on our southern border won't stop it.

For too long, Washington has chosen denial and obstruction. But the timeline that compels us to act isn't set by Congress -- it's being dictated by science. With climate catastrophe on the horizon, we've reached a now-or-never moment in our history. To meet this crisis, we must channel all of our energies into a national project -- one that draws on the resources of every American, from big cities to rural communities, and seizes the tremendous opportunity of a new era of climate action. As big as this crisis is, our ideas and aspirations are big enough to meet it. When I'm president, we will.

Pete Buttigieg

First, we'll set an ambitious goal to transform America into a net-zero emissions society no later than 2050 -- and spur the innovation to get us there. We'll nearly quadruple R&D investments in advanced wind and solar, battery storage, and carbon capture to $25 billion a year -- more than the Manhattan Project. Many of these investments will be financed by Climate Action Bonds, modeled on World War II war bonds, which will allow every American to own a piece of our clean energy future.

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