Craig Dunnum didn’t read the recently released National Climate Assessment (NCA), which predicts the nation’s farm commodity contribution to the economy — $136.7 billion in 2016, already low due to falling prices — will be increasingly vulnerable to droughts, floods, pests and disease.

Instead, he lived it.

The fourth-generation farmer in south-central Wisconsin has been through four 100-year floods in the past eight years. This year was the worst, with 20 inches of rain in 10 days. Two dams broke, flooding the small farming community nearby with eight feet of water. Corn and hay fields were wiped out; cattle were killed. “Farmers around here are generally of Scandinavian descent,” he says. “We don’t ask for help, but I’ve never seen anything like this before.”

Devastating floods may be extreme, but they are not the only changes underway. When he first took over the family dairy farm almost 22 years ago, Dunnum transitioned the operation to organic beef production. He and his neighbors planted their crops after Memorial Day and harvested them in November. Now they plant around the middle of May and harvest in December.

Two decades ago, Dunnum, like many farmers, scoffed at global warming. “I didn’t take [climate change] seriously,” he recalls. Now, he says, “Everybody buys into the fact that things have changed; we’re just not sure what we can do about it.”

The fourth U.S. National Climate Assessment, released in late November, adds new details to the steady drumbeat of reports with the same overarching message — climate change will increase rates of crop failure, decrease crop yields and livestock productivity and make many crops more vulnerable to pests, weeds and disease. Rural communities, dependent on agriculture, are particularly exposed to climate volatility. In other words, business will not continue as usual.

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