Most of the statisticalstudies correlate crop yields at a province or county scale fromcensus data with seasonal climate computed during a coarse andfixed crop growth period. In fact, cropping systems have shiftedin the past few decades under the combined effects of climatechange, cultivars turnover and agronomic management (Welchet al., 2010; Tao et al., 2012a,b; Tao and Zhang, 2013). There is a clearand present need to synthesize crop yield and climate data from