CHAMPAIGN, Ill. - Farmers who keep an eye on the sky and an ear tuned to the local weather report will also want to pay attention to long-term climate change trends which may sway production decisions down the road.

“Farmers ask me more questions about climate change than any other group,” said Illinois State Climatologist Jim Angel, Prairie Research Institute, University of Illinois. “Climate change affects their bottom line, so they need to know about temperature and precipitation changes that will influence their operation.”

Climate is the long-term average weather, and changes are important to watch. In Illinois, too much rain and a damp climate, especially in the spring, can lead to delayed planting, soil erosion, and saturated soils. With a 10 to 15 percent higher precipitation average annually, this trend, which started in the 1960s, has become more pronounced in the past 10 years across the Midwest.

This year Illinois experienced the third wettest July on record, and last year was the wettest June and second wettest December on record.

Temperature changes have not been as dramatic as those of precipitation, but summers have more frequent humid weather, which is uncomfortable for livestock. High dew point temperatures, a measure of humid conditions, used to be rare, Angel said. In the past few years, these conditions are more likely to occur. With high humidity, temperatures don’t cool down as much in the nighttime hours.

The milder winters experienced in the past two years in Illinois allow more pests, weeds, and pathogens to overwinter in Illinois. Such effects of climate change may lower crop yields and quality, requiring changes in management practices.

Mild winters also coax spring plants to emerge too early, increasing their risk for a spring frost. These conditions occurred in 2007 and 2012, when apple and peach trees failed to deliver a bountiful crop.

Angel encourages farmers to use climate change tools on the Useful to Useable (U2U) website (AgClimate4U.org). The site features an ag climate viewer, climate patterns viewer, corn nitrogen rate calculator, probable fieldwork days, and other tools. U2U is an integrated research and extension project that helps farmers adapt to climate change and make better long-term plans.

“People often compare this year with previous years, thinking this year is like it was in 2012 or 2014,” Angel said. “They try to predict future weather based on conditions from a previous year. But no two years are ever alike.”