The Future of North American Wheat Production
Olmstead, A.L. and Rhode, P.W. 2011. Adapting North American wheat production to climatic challenges, 1839-2009. Proceedings of the National Academy of Sciences USA 108: 480-485.
Working with a new county-level dataset on wheat production and climate norms, Olmstead and Rhode analyzed how North American grain farmers pushed wheat production into environments once considered "too arid, too variable, and too harsh" to successfully cultivate wheat during the 19th and 20th centuries.
With respect to the challenge of insufficient soil moisture, the two researchers report that the median annual precipitation norm of the 2007 distribution of North American wheat production was only one-half that of the 1839 distribution. And with respect to the challenge of the cold weather that was faced by many of the settlers of the northern United States and parts of Canada, the median annual temperature norm of 2007 was 3.7°C lower than that of the early norm. The agronomic advancements that enable wheat to be grown today under earlier inhospitable climatic conditions occurred mostly before 1929 and required "new biological technologies," in the words of Olmstead and Rhode; and they report that comparable "biological innovations" were "crucial to the expansion of production in hot-arid areas such as Texas, Oklahoma, central California, and northern Mexico."
More recently, of course, came the Green Revolution that is associated with the pioneering work of Norman Borlaug, which Olmstead and Rhode describe as "an important advance in this longer process of biological innovation," and which they say has been so successful that "between 1839 and 2009, wheat output increased 26-fold in the United States and more than 270-fold in Canada."
The two economics professors say "there will be enormous challenges to the agricultural sector associated with impending climate changes," apparently believing the predictions of the IPCC. Yet they feel confident that modern agronomic research will enable us to meet this challenge, concluding that "reinvigorating public support for research to promote agricultural adaptability should be a high policy priority."
We agree with their suggestion, noting that it is a rational course to take even if one does not believe in the IPCC predictions; for earth's climate system is still a great enigma, and either significant warming or cooling could commence at any time, as the climate alarmists of a few decades back discovered, when after predicting an imminent bout of catastrophic global cooling, the world suddenly began to warm. Preparations "to promote agricultural adaptability" should thus be made for all potential climate-change scenarios.