Monday, September 2, 2013

Return of Mid-Continent Drought

After four months of heavy rain and flooding, it would be hard to imagine a drought in the central United States. It seemed that 2013 would be an exception to the dry summer pattern that has set in since 2010 in the North American mid-continent. Yet the rain all but stopped after the summer solstice, and more than half of the mid-continent region has seen drought conditions since then. Half of the contiguous United States is in moderate to severe drought at the latest report. Drought conditions extend from Texas to California in addition to the mid-continent, and on the drought map, almost the entire area west of Chicago and the Mississippi River is affected. There are many places where it almost didn’t rain in August.

The corn crop should come out fine in fields that were planted on time. Corn doesn’t depend on steady rain in late summer, though it may not grow much after a few weeks without rain. Unfortunately, many fields were planted late because of the spring mud, and those fields depend on the return of rain in September. Recent experience says that’s likely enough, but as a farmer, you hate to count on it.

It looks like this year’s U.S. corn crop will be similar to last year’s. There won’t be a shortage, but high prices for corn will keep prices for meat and milk — that’s where most of the corn crop goes — high into next year. Corn ethanol factories won’t have much corn to work with, and those that closed because of high corn prices last year won’t be able to reopen this season. This takes away about 1 percent of the U.S. gasoline supply and translates to prices elevated by roughly 10¢ per gallon nationally for the next year.

The mid-continent summer “drought” pattern may be a permanent effect of a warmer Arctic region. That’s a prediction of some global climate models, as there is no longer a source for the cold air masses that trigger most mid-latitude mid-continent summer storms. The same models predict more flooding events in mid-continent, with a diminished jet stream. Aside from arriving years earlier than expected, the summer weather pattern shift in the North American mid-continent is generally consistent with what was predicted.