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25 May 2017

Rising Temperatures Threaten Cereal Grain Yields as Climate Change Takes Effect

As wheat remains the most-widely grown crop in the world, joining rice as the top two sources of calories for human consumption around the globe, it stands to reason that any major disruptions to its growth and supply would be a cause for concern. Hence why the results of a recent study published by the University of California, Davis provides a certain measure of worry, as it asserts that by the close of the 21st century yields of such grains will be significantly compromised by the effects of climate change.

The UC Davis study found that yields of wheat, barley, and other cereal grains could drop by 17-33% by the end of the century, potentially making supply somewhat scarce and pushing up prices as a result.

To make their predictions, the researchers analysed a new statistical model developed by UC Davis and Cornell University. Based upon 65 years’ worth of weather records, examined alongside wheat and barley yield data from France, the study is the first to present evidence of the damaging effects of warming on yields of cereal grains such as wheat and barley.

“This is not to be interpreted as saying that yield will decrease regardless of any technological improvements that may be made in the future,” said co-author Matthew Gammans, a UCD graduate student working with Professor Pierre Mérel in the Department of Agricultural and Resource Economics.

“It does suggest, however, that climate change will lessen the rate of any yield improvements that will be achieved by technological advances.”

The study directed its focus at three specific grains, namely winter wheat, winter barley, and spring barley, chosen not only for their prevalence around the world, but also due to the fact that they rely primarily upon rainfall rather than irrigation for watering. Based on the available weather and yield data, the following predictions were made for the end of the century:
  • Under the most severe warming scenario, yield declines will be 21 percent in winter wheat, 17.3 percent in winter barley and 33.6 percent in spring barley.
  • The negative impacts of increased heat during climate warming won’t be offset by a decrease in extreme cold temperatures during winter.
  • Possible increases in rainfall would help mitigate the effects of heat stress but would not be sufficient to offset the negative impacts of warming temperatures.
Technological improvements are hailed by the study as our potential saving-grace, effectively offsetting many of the negative effects of climate change on crop yields via the use of heat-tolerant crop varieties and advances in farming methods.

“We now want to explore what role adaptation to climate change will play in mitigating negative impacts on yields of wheat, barley and other cereal grains,” concluded Gammans.

Sam Bonson

Sam is an aspiring novelist with a passion for fantasy and crime thrillers. He is currently working as a content writer, journalist & editor in an attempt to expand his horizons.