Author
TOMASEK, BRADLEY - University Of Illinois | |
Williams, Martin | |
Davis, Adam |
Submitted to: Agronomy Journal
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 2/3/2017 Publication Date: 5/1/2015 Citation: Tomasek, B.J., Williams, M., Davis, A.S. 2015. Optimization of agricultural field workability predictions for improved risk management. Agronomy Journal. 107(2):627-633. Interpretive Summary: Risk mitigation and adaption to climate change in agricultural systems is essential to ensuring a sufficient food supply for the future. One important dimension of making agricultural systems more resilient to climate change is understanding how field working days are influenced by regional variation in soil physical properties and weather patterns. We investigated changes in season length, spring field workability, and summer drought risk within the state of Illinois under three different climate change modeling scenarios (B1, A1B, and A2), at both the mid-century and end of century, down to the crop district scale. Across all scenarios and districts, overall growing season length increased. However, small increases in early spring field workability due to early warming were eroded by declines in mid-summer field working days due to excessive rainfall. In addition, drought frequency and severity during the summer was projected to increase over much of the state for most scenarios. One exception was the least intense B1 scenario, which showed a few districts with a reduced drought risk. Among many of the districts projected to experience increased drought risk, field workability is also projected to decrease which may interfere with adaptation measures requiring changes to management timing. These results highlight the spatial variability in climate change at small scales and the unique challenges this presents to mitigation and adaptation efforts. Technical Abstract: Risks introduced by weather variability are key considerations in agricultural production. The sensitivity of agriculture to weather variability is of special concern in the face of climate change. In particular, the availability of workable days is an important consideration in agricultural practices which is primarily driven by temperature and precipitation, both of which may be altered by climate change. We investigated changes in season length, spring field workability, and summer drought risk within the state of Illinois under three different SRES scenarios (B1, A1B, and A2), at both the mid-century and end of century, down to the crop district scale. Across all scenarios and districts, thermal time units increased substantially in parallel with a longer frost-free season. The magnitude of these changes followed the ranks of temperature changes among the scenarios. A small increase in late March and Early April field workability was consistent across districts and scenarios, but a decline in overall April through May workable days was observed for many cases. In addition, drought frequency and severity during the summer was projected to increase over much of the state for most scenarios. One exception was the least intense B1 scenario, which showed a few districts with a reduced drought risk. Among many of the districts projected to experience increased drought risk, field workability is also projected to decrease which may interfere with adaptation measures requiring changes to management timing. These results highlight the spatial variability in climate change at small scales and the unique challenges this presents to mitigation and adaptation efforts. |