Economic research on decadal climate variability (DCV) is scarce. DCV refers to ocean-related climate influences of duration from seven to twenty years. The DCV phenomena and their phases are associated with variations in crop and water yields. This paper examines the value of DCV information in the Missouri river basin using a mathematical programming model. The analysis shows the value of a perfect forecast is about 5.2 billion dollars, though 86% of this value can be obtained by a less perfect forecast based on already available data. Results show differential responses in major crops acreage and water usage.