Crop heat stress in the context of Earth System modeling

Siebert et al (2014 Environ. Res. Lett. 9 044012) suggest that crop models do not represent the effect of heat stress on crop yield adequately unless they apply such effect to sensitive phases in a crop's growth cycle. Siebert et al focus particularly on the phase considered most sensitive for wheat yield in Germany, the time of anthesis. Siebert et al find that observed canopy rather than 2 m or ground temperature better quantifies the effect of heat stress during anthesis on wheat yield in Germany when evaluated against data from pot experiments under controlled conditions.