Increasing risks of multiple breadbasket failure under 1.5 and 2 °C global warming (Ag Systems)

Crop yields are vulnerable to rising temperatures and changes in precipitation. Here, Gaupp et al. model the projected crop yields at 1.5 versus 2.0 degrees of additional warming, as part of the HAPPI experiment (perhaps a misnomer: Half a degree Additional warming, Prognosis and Projected Impacts). The authors look at risk of extreme weather events during the period when crops (wheat, soybean and maize) are growing and being harvested, and how these events will affect yield. They model local effects in each of the world’s major breadbasket regions (e.g., southwest Australia, Argentina, western China etc.) under current, 1.5 and 2 degree warming. Not surprisingly, both warming scenarios indicate yield losses, but what is particularly notable is that in the 2 degree warming the impacts are likely to be felt across all regions, leading to global shortages. (Summary by Mary Williams) Agricultural Systems 10.1016/j.agsy.2019.05.010. On a similar note, here’s a new paper by Kornhuber et al that shows how Amplified Rossby waves enhance risk of concurrent heatwaves in major breadbasket regions (basically, circumglobal oscillations of the jet stream can lead to simultaneous heatwaves in several key food production areas at the same time), from Nature Climate Change 10.1038/s41558-019-0637-z.