Soil health needs soil carbon

Our future will become warmer, precipitation will become more variable and extreme, and the growing season will continue to lengthen. But careful planning and adaptive action can reduce those risks. There are many ways for producers to adapt to climate change based on the situation and needs of a particular farm. And those changes can start now.

Climate models show the Midwest is likely to see an increase of 10 degrees by the end of the century. That’s the future where we start cutting back on fossil fuels and look at conservation practices. A greater-emissions model is based on an increase of 15-20 degrees by the end of the century. No-one wants to see the outcomes of that scenario.

“Remember that’s important because1 degree warmer means 4 percent more water vapor in the atmosphere,” said Justin Glisan, State Climatologist with the Iowa Department of Agriculture and Land Stewardship. “At 10 degrees toward the end of the century, that’s 40 percent more water vapor in atmosphere, leading to increasingly extreme events. We’ll see high probability of aerial flooding as we move into the next several decades.

“With more water vapor availability in the atmosphere, with changes in the large-scale climate system, we see the Bermuda high becoming stronger, the Rocky Mountain low becoming stronger, more moisture from the Gulf infiltrating into the upper Midwest and see higher-humidity scenarios. There are implications on livestock health, higher temps, higher heat index, more-frequent and higher-intensity rainfall events within the climate projections. And with more water vapor, more cloud cover, we reduce the daily temp range. Our overnight lows are not getting as low as they should; the water vapor and cloud cover prevents longwave radiation getting out at night.

“We’ve had more than 120 tornadoes across Iowa this year, and hail and a derecho. We’re seeing an increase in March, April and May of severe storms. The ingredients that we need – more moisture, higher temps, more instability – are existing as we get toward the middle of the 21st century. Those are increasing as we reach the middle of 21st century.”

Wisconsin is looking at the same changes as Iowa. According to a 2023 report by the U.S. Department of Agriculture, average annual temperatures in the state increased by 1.6 degrees from 1979 to 2021. Nighttime lows have warmed even more than daytime highs. Autumns and springs have warmed the most compared to long-term averages, resulting in more than an additional week of the growing season. Average annual precipitation has increased significantly – by 4.9 inches – with the greatest increases again during the spring and winter months. Extreme-precipitation events of greater than 2 inches in one day have become more frequent – adding 1.1 days of them per year.