Hillaker says this current drought is following a pattern similar to the 1988-89 dry spell. The summer of 2012 ranked fifth-driest and 14th hottest in 140 years of records. In 1988, the rankings were somewhat reversed but still high as that summer was the fourth hottest and 14th driest.
For most of Iowa, groundwater levels are lower now than at this time last year. "Thus, it's almost a sure thing we will be starting 2013 further in the hole than we did in 2012," says Hillaker. "That means 2013 doesn't need to be as dry as 2012 for conditions to become worse than they are now."
"We are sitting on a real deficit in soil moisture," Hillaker adds. "Looking at river, stream, lake levels and water tables, 1989 is the worst year. It prolonged the dryness of 1988. And we are experiencing the same thing right now. Until you overcome the deficit in soil moisture, you aren't going to move much water to the water table." He says if Iowa has a lot of snow this winter, it may help a little. But snow only accounts for a small amount of the moisture needed. "And, moisture can't enter frozen soil," he notes.
Even if rainfall returns to normal in spring, it won't be enough to fully recharge subsoil moisture
Although we might receive a more normal amount of precipitation in 2013, the ground is still depleted. "We are now way behind where we should be on subsoil moisture," adds Hillaker. "Much of our recovery depends on the moisture we get between October and April. And we didn't get enough this fall. Looking back at last spring, because of last year's warm winter, we were already at risk at the beginning of the 2012 growing season." Soil moisture is better now everywhere in Iowa than it was at the end of the summer, but it is not as good as needed.
The U.S. drought monitor this past week reported drought conditions were about the same in Iowa as the previous week—no improvement. For weekly updates, you can follow that indicator at http://droughtmonitor.unl.edu/. Most of Iowa currently ranges from extreme to severe to moderate drought, according to the drought monitor map.
Farmers weathering 2012 are learning plenty about everything from crop insurance to seed genetics as parched conditions reshape farm business across the country. Consider our 5-part approach to moving ahead after the toughest drought since the 1930s.