Researchers from Australia, Germany and the US have successfully quantified the effect of climate extremes on global crop yield variations. They concluded that general extremes, like drought and heatwaves, that have occurred during the growing season of crops such as maize, rice, and soy, accounted for 20% to 49% of yield fluctuations.
In recent years, policymakers across the world have launched initiatives to increase the amount of “soil organic matter,” or SOM, as a way to improve soil health and boost agricultural production. Although SOM is considered key to soil health, its relationship with yield is contested because of local-scale differences in soils, climate, and farming systems. There is simply limited evidence that this strategy will actually improve crop output.