On Tuesday, October 20, 2015 at 2:00:55 AM UTC-4, Jasen Betts wrote:
Corn and soy are grown in only a handful of geographically contiguous state s in the U.S. The weather during the growing season of 2014 was atypical, i t could have easily gone the other way. The long term average of crop yield will be the deciding factor as to the effects of global warming. The previ ous USDA paper I linked shows that decline in yield due to detrimental pert urbations of ideal growing conditions are nonlinearily steeper than yield i mprovement due to beneficial climatic perturbations, so it doesn't take a r ocket scientist to understand the long term average yield will go into decl ine.
"Understanding climate effects on crop yield has been a continuous endeavor aiming at improving farming technology and management strategy, minimizing negative climate effects, an d maximizing positive climate effects on yield. Many studies have examined climate effects on corn yield in different regions of the United States. However, most of those studies used yield and climate records that were shorter than 10 years and were for different years and localities. Although results of those studies showe d various influences of climate on corn yield, they could be time specific and have been difficult to use for deriv ing a comprehensive understanding of climate effects on corn yield. In this study, climate effects on corn yield in central Missouri are examined using unique long-term (1895?1998) datasets of both corn yield and climat e. Major results show that the climate effects on corn yield can only be explained by within-season variations in rainfall and temperature and cannot be distinguished by average growing-season conditions. Moreover, the growin g-season distributions of rainfall and temperature for high-yield years are characterized by less rainfall and warmer temperature in the planting period, a rapid increase in rainfall, and more rainfall and warmer temperat ures during germination and emergence. More rainfall and cooler-than-average temperatures are key features in the anthesis and kernel-filling periods from June through August, followed by less rainfall and warmer temperatures during the September and early October ripening time. Opposite variations in rainfall and temperature in t he growing season correspond to low yield. Potential applications of these results in understanding how climate change may affect corn yield in the region also are discussed."
From:
All of the plant science research on the effects of CO2 indicate the uptake is already saturated.