Temperature thresholds of extreme heat-induced yield loss in maize and soybean reveal geographic heterogeneity across the Northern Hemisphere

Zhao, Q., Wang, C., Wang, X., Rezaei, E.E., Müller, C., Wang, E., Webber, H., Zhang, L., Li, X., Sang, Y., Zhao, G., Folberth, C. ORCID: https://orcid.org/0000-0002-6738-5238, Jain, A., Liu, W., Okada, M., Zabel, F., Jäegermeyr, J., Guo, H., Zhang, Y., Jiang, Y., et al. (2026). Temperature thresholds of extreme heat-induced yield loss in maize and soybean reveal geographic heterogeneity across the Northern Hemisphere. Nature Food 10.1038/s43016-026-01298-0. (In Press)

Full text not available from this repository.

Abstract

Exposure to extreme high temperatures is a major constraint on global crop productivity, yet most large-scale assessments rely on fixed temperature thresholds that overlook regional variation in genetics, environment and management. Consequently, the temperature thresholds at which heat exposure begins to cause substantial yield loss and their spatial variability remain unclear. Here we compiled subnational yield census over Northern Hemisphere (20° N-55° N) and analysed the extreme degree days (EDDs) to estimate a data-driven critical threshold (EDDthreshold). Our findings reveal EDDthreshold for maize and soybean are 34.8 ± 4.0 °C and 33.7 ± 3.9 °C, respectively. In contrast, state-of-the-art crop models significantly underestimated EDDthreshold and its spatial variations, leading to overestimated extreme heat exposure, partially explaining their underestimate in yield loss during extreme heat events. We estimate that without adaptations, growing-season extreme heat exposure could increase by 2.4%-16.1% for maize and 4.9%-16.0% for soybean by the end of the century, and sowing-date adjustment alone cannot fully offset the projected increase in extreme heat exposure.

Item Type:	Article
Research Programs:	Biodiversity and Natural Resources (BNR) Biodiversity and Natural Resources (BNR) > Agriculture, Forestry, and Ecosystem Services (AFE)
Depositing User:	Luke Kirwan
Date Deposited:	19 Feb 2026 12:49
Last Modified:	19 Feb 2026 12:49
URI:	https://pure.iiasa.ac.at/21334

Actions (login required)

View Item