Adjacent to my organization's headquarters on the Elizabeth River in Norfolk, Virginia, is a picturesque neighborhood called The Hague. Two decades ago, The Hague would flood only during severe storms. Now, it routinely floods during high tides. It gets so bad during nor'easters my fellow staffers have been known to ferry each other across the parking lot in the small boat we use for water rescues.

Norfolk has been called ground zero for sea-level rise. So I know that the devastating effects of climate change are real: I have seen them with my own eyes. But do I expect the government to bail us out—literally and figuratively? Let's just say I'm not tossing out my snorkel. Rather, in Republican parlance, I'm pulling myself up by my swim fins and taking personal responsibility for addressing climate change—by eating vegan.

There is probably no single activity each of us can do that would combat climate change more than changing what we eat—not switching to a hybrid car, not tearing up our lawns and replacing them with native plants, not installing solar panels on the roofs of our homes.

"Reducing global meat consumption will be critical to keeping global warming below the danger level of two degrees Celsius," according to Laura Wellesley, a researcher at London-based think tank Chatham House. The effect on the climate of what we put into our mouths three times a day, 365 days a year, is huge.

How huge is it? Every year, we raise and kill more than 9 billion animals for food in the U.S. alone. That's more than the human population of the entire planet—and that's just to feed Americans, who eat more meat per capita than the people of any other nation on Earth. Those billions of animals are gobbling up precious resources—including water, land, fossil fuels, corn, grain, and soybeans—and they're producing millions of tons of waste.

If you fly over Maryland's Eastern Shore, you can see huge chicken factory farms laid out for miles and miles, as far as the eye can see. It's breathtaking in a depressing, post-apocalyptic way.

In addition to all that waste—which in the case of those Eastern Shore chicken farms, is largely to blame for bacteria and other pollutants in the Chesapeake Bay—animals raised for food emit a tremendous quantity of greenhouse gases. According to the U.N. Food and Agriculture Organization, animal agriculture sends 7.1 gigatons of carbon dioxide into the atmosphere each year.

It's also the largest source of both methane and nitrous oxide, which are 25 and 300 times more destructive than carbon dioxide, respectively. Added together, the raising and killing of billions of animals for food every year is responsible for at least 51 percent of greenhouse-gas emissions worldwide, according to a report published by the Worldwatch Institute.

The good news is that we can make a difference, you and I, whether we live in Paris, France, or Paris, Arkansas. According to a recent study published in the Proceedings of the National Academy of Sciences, a widespread switch to vegetarian eating could curb greenhouse-gas emissions by nearly two-thirds, while switching to vegan foods would cut them by a staggering 70 percent.

As an added bonus, the study found that more than 8 million human deaths worldwide could be prevented over the next three decades if people replaced their hamburgers with veggie burgers. Already, Buddhist monks in China are offsetting roughly 40 million tons of greenhouse gases per year just by eating plant-based meals, according to an Arizona State University study.

Thank you, Buddhist monks. I think I see the tide starting to turn.