Long-Term Weather Predictions Could Help Farmers

Oklahoma has had a wet spell for about 20 years now, interrupted only by occasional seasonal droughts. For the area that suffered the brunt of the Dust Bowl of the 1930s, and a subsequent similar drought in the 1950s, the predominantly above-average precipitation is great news.

A wet cycle is obviously beneficial in dry areas like Oklahoma, but in some locations it can lead to flooding that destroys crops and farmland. Dry cycles are never good news for farmers in sub-humid climates.

Predicting these spells seems like a good idea, but how much difference would it really make? Jurgen Garbrecht, a hydrologic engineer at the ARS Great Plains Agroclimate and Natural Resources Research Unit in El Reno, Okla., and colleagues are looking at 100-year rainfall records to see if advance knowledge of wet and dry periods would really help farmers.

Garbrecht wants to identify the length of the dry and wet periods and their significance to agriculture. He wants to learn if it is worth finding ways to predict a dry or wet cycle ahead of time: Would farmers then be able to take actions that would improve their bottom lines?

In a separate project, Garbrecht and colleagues are looking at the National Oceanic and Atmospheric Administration extended climate forecast records for similar reasons to see if they are useful to farmers and, if so, in what regions of the country. It may be that such forecasts are only accurate enough to be useful to farmers in areas where climate departures from average conditions are more predictable. In other parts of the country with more confusing weather patterns, the forecasts may be so weak that they're of little practical use.

ARS is the U.S. Department of Agriculture’s chief scientific research agency.