AMES, Iowa — To snow or not to snow? How much rain is enough — and too much? Dry times in Georgia?
Elwynn Taylor, professor of ag meteorology at Iowa State University in Ames, will deliver a 2017 crop weather outlook during the 2017 Greater Peoria Farm Show.
Illinois AgriNews talked with Taylor about five things people in agriculture should know about weather and climate right now.
1. Soil moisture, not low, but good, makes the chances of ground being too wet at planting higher.
“Our late growing season precipitation was more than ample — as people who were trying to harvest were aware. But following, with the crop finished using water, the soil profile is very nearly at water-holding capacity for most of the Corn Belt. That water will still be present come planting time in the spring,” Taylor said.
2. An uncertain La Niña, but some hints a drought may develop in the deep South that could impact the eastern Corn Belt in 2017 and the whole Corn Belt in 2018.
“The thing that everyone can identify with in the Midwest is 1987. The drought in the Southeast was so bad that farmers in Iowa, Minnesota and Wisconsin donated hay and trucks to haul it down to the Carolinas so they could save their breeding stock,” Taylor said.
“Then the next year, 1988, the farmers down there returned the favor and sent hay to us because of our 1988-‘89 drought and we didn’t have enough feed for our animals. All of the major droughts have started there. This includes the Dust Bowl. The Dust Bowl started there. They didn’t have a Dust Bowl, but that’s where it started, and it got worse as it came west,” he said.
3. The chance of an extreme crop is enhanced this decade over the 1992-2011 period.
“We have periods where there’s greater variability from year to year for crops. We’ve had very little variability in the 18-year period preceding 2011. There were 18 years of really fairly consistent crops following 25 years of very variable crops from year to year. If the pattern holds true that has been the pattern since back over 400 years, if we look at tree rings, we have 25 years with extremes, extremely bad, extremely good, like we did in the 1980s, then 2012 would have been year one of 25 years of erratic years for crop yields,” Taylor said.
4. The climate over a 20-year period is likely to have a 100-year flood with our new weather patterns.
“The ‘100-year flood’ is a 1 percent chance that it could happen in a year. They don’t mean it happens every 100 years. It means there’s a 1 percent chance it could happen in any year. That 1 percent chance was determined in the 1950s, when hydrology studies were done,” Taylor said.
Since then, though, rainfall has been on the rise.
“Since then, we’ve had more rainy days. We have more precipitation for the year by about 20 percent in the western Corn Belt, and this extra 20 percent that’s falling is excess, so it contributes to high water. We have to expect what they call the 100-year flood. Now it will come up every 17 years that high instead of every 100 years. So, in other words, it’s a 6 percent chance or a 7 percent chance, rather than a 1 percent,” Taylor said.
5. Watch for reports of extremes in precipitation — rain or snow — in the Yukon. When they go to extremes one way, the Corn Belt often does too — but in the opposite direction.
“The Yukon has not gone wet, and the forecast for the winter from the National Weather Service is for normal conditions up there. If they’re off to a real wet start, we’re in trouble. For example, 1988, east of I-35, had less precipitation than we did in 1936. It wasn’t as hot, so it wasn’t as bad a drought as in 1936, but it was less precipitation. They had record high precipitation in the Yukon,” Taylor said.
Extra credit: Is the weather getting more variable or is this cyclical?
“Because it is a 25-year period in the cyclic periods, it’s very hard to separate this out from a long-term climate shift. People haven’t been thinking about the shifting, changing climate to handle these cycles where we have 25 years of shifting weather and the next 20 are mild weather. People haven’t been thinking in terms of that. This is definitely a cyclic thing. It’s got over a 400-year history in the Midwest. We identify that by how trees show their annual growth,” Taylor said.