Here’s What a Carbon Offset Actually Looks Like

I’m looking at a trench on part of a 7,500-acre ranch outside Big Timber, Montana. It is February. Swollen, purple clouds roll over the pastures.

Ranch owner Kevin Halverson, 70, spent the morning shoveling snow out of the trench. It is roughly as wide as a man and shoulder deep and was cut for a new two-inch pipeline that now snakes for more than five miles across his fields. The water will allow his cattle to graze the land in a more intensive way.

Halverson is wearing a jacket shredded at the elbows, and his cheeks burn like alpenglow on the 11,000-foot Crazy Mountains in the background. This is backbreaking work.

“I may have abused this land more than I should have, trying to make my payments,” Halverson says. Faced with so much overhead—land and equipment leases, in addition to the cost of power, weed removal, and disease treatment for livestock—today many ranching families need an extra source of income to stay afloat.

Halverson climbs out of the trench and looks around. Pickups. Cows. A scar of freshly turned earth. The pipeline will bring water to tanks stashed among the thirstier corners of his ranch, which will allow him to run more cattle and earn more than he could before. But the trench does even more than that. Thanks to the pipeline, Halverson can now harvest carbon out of the sky and be paid for it.

“For ranchers of my age, this is, like, something from Mars,” he says.

The Halversons are one of four families in Montana behind a new effort called the Montana Grasslands Carbon Initiative, which seeks to pay ranchers to fight climate change by letting the grasses grow tall across their rangelands. If you change the way cows graze, the thinking goes, you can give huge swaths of chewed-up grasslands time to regrow properly. More grass means more photosynthesis, the process plants use to convert light energy into food. More photosynthesis means more carbon dioxide is siphoned out of the atmosphere and excreted back into the earth as organic compounds. That makes the soil richer with nutrients, oxygen, and water, which in turn leads to healthier grasses.

Scientists can measure how much carbon the grasses are converting, too, and every metric ton (about 2,200 pounds) of that sequestered gas has a value derived from a demand to not have it floating around the planet. The strange, complicated world of carbon offsets turns that greenhouse gas into a commodity worth real money.

Standing next to Halverson and his very long trench, I was more or less witnessing the birth of an offset. Until then, offsets had seemed abstract and intangible to me. As an avid traveler, how many times have I been asked to offset my flights, offset my Lyft, offset my attendance at a conference? Does spending $7.22 to offset a round-trip flight from San Francisco to Kauai really do anything for the environment?

Here, I can see the dirt on Halverson’s gloves and the snot cooling in his nose. I can fathom how the promise of a carbon payment and healthier soil could reduce his overhead costs and shorten the road to profitability. Also, getting a check to fight climate change? “That’s gravy,” he says.

To limit global warming to about 3.6 degrees Fahrenheit over preindustrial levels, scientists at the International Energy Agency say the world needs to slash global emissions to less than 20 billion metric tons a year by 2050—down from 33 billion in 2019—and down to zero by the end of the century. (Even then, we’ll still likely have more droughts, severe floods, and destructive storms.) Offsets will play a role in flattening that curve. Some state governments may follow California’s example and create policies that by law require certain high-polluting industries, like power plants, to offset their emissions. Other companies, like REI, buy offsets voluntarily, because their customers want to support an environmentally minded brand. In between lies a complex scheme where a traveler looking to take a guilt-free trip can get pretty lost.

“People assume all carbon offsets are the same, and that’s absolutely not true,” says Paul Gambill, founder of a Seattle-based carbon-trading company called Nori. “There’s not always a good link between the offset and, OK, what does this even mean?”

To figure that out, Montana’s a great place to start.