A peer-reviewed analysis of field trials and crop simulations found stronger climate-related yield gains in the northern US Corn Belt, with weaker or negative contributions farther south. The work covers 1991–2024 in five states. Weather conditions interacted with crop development and the maturity of planted hybrids, while a model holding maturity constant reduced the regional contrast.
A peer-reviewed analysis found regional differences in climate’s contribution to maize harvests in the central United States, combining field trials with crop modelling. The work covers Minnesota, Wisconsin, Illinois, Iowa and Missouri during 1991–2024. Northern locations gained more from favourable climate conditions, while contributions farther south were smaller or negative.[1]
Summer daytime temperatures in this region have warmed more slowly or cooled, a pattern known as a regional warming hole. Researchers followed crop development from planting rather than relying on fixed calendar months. This accounted for weather arriving at different growth stages, alongside the maturity duration of the hybrids planted. The historical regional pattern’s future persistence remains uncertain.[1]
A further model experiment kept hybrid maturity constant and showed a weaker north–south contrast. Variety choices may reflect harvest schedules and drying costs, as well as heat or water stress late in the season. Analyses spanning shorter periods also changed the estimated climate contribution. The findings concern climate interacting with the varieties and management practices used in the study region.[1]
