An overwhelming scientific consensus maintains that climate change is due primarily to the human use of fossil fuels, which releases carbon dioxide and other greenhouse gases into the air. The gases trap heat within the atmosphere, which can have a range of effects on ecosystems, including rising sea levels, severe weather events, and droughts that render landscapes more susceptible to wildfires.
Fear is rife that agriculture sector is seriously under threat by climate change which is affecting wheat production.
Many studies have suggested that rising temperatures could be harmful to farms around the world, although there is plenty of uncertainty about how bad things will get and which food supplies we should worry about most.
A new study by Nature Climate Change reiterated concerns that wheat the most significant single crop in terms of human consumption might be in big trouble.
After comparing multiple studies used to predict the future of global crop production, researchers have found that they all agree on one point, that the rising temperatures are going to be really bad for wheat production.
Scientists use a wide range of techniques to make predictions about the future of the environment, including a variety of models and statistical analyses. Often, though, there is debate about which technique produces the most accurate results.
The authors of the new study, who include dozens of scientists from institutions in China, the United States, Europe and elsewhere around the world, decided to compare three different methods used to assess the impact of temperature changes on wheat production.
These included a type of statistical analysis that relies on historical observations of climate and global wheat yields to make inferences about the future, as well as two different types of model simulations.
For the purposes of the comparison, the researchers focused only on the effects of temperature, without incorporating other climate-related factors such as rising carbon dioxide levels or changes in precipitation.
Specifically, all the techniques suggested that a global temperature increase of one degree Celsius would lead to a worldwide decline in wheat yield by between 4.1 and 6.4 percent.
The world currently produces more than 700 million tons of wheat annually, which is converted into all kinds of products for human consumption, including flour for bread, pasta, cakes, breakfast cereals and more.
A reduction of just five percent would translate to a loss of about 35 million tons each year and that could spell big trouble for the global food supply.
A new report from the United Nation’s Food and Agriculture Organization (FAO) projected that world wheat production for the 2016/17 year would hit 741 million tons, nearly 500 million of which is destined to be used directly for human consumption.
While global production of coarse grains, including corn, does outweigh the production of wheat, a significantly smaller proportion of it goes to human consumption worldwide, with the rest being used for animal feed and industrial purposes.
According to the FAO, global human consumption of coarse grains comes to about 200 million tons annually.
The various studies also produce similar findings on a country level for the world’s largest wheat producers, including the U.S., China, India and France.
For instance, all of the study methods suggested that China will see yield reductions of about 3.0 percent per one degree Celsius increase in global temperature while India was projected to experience much greater declines of about 8.0 percent.
In general, the results suggest that warmer regions of the world will experience the greatest temperature-related losses.
However, the agreement among the different study methods on exactly what these losses will be was less consistent for smaller countries than for the larger producers.
“The consistent negative impact from increasing temperatures confirmed by three independent methods warrants critical needed investment in climate change adaptation strategies to counteract the adverse effects of rising temperatures on global wheat production, including genetic improvement and management adjustments,” the researchers wrote in the paper.
There are still some major uncertainties, though. For one thing, the researchers note, the agreement among the different types of studies became less consistent above one degree Celsius of warming. And there was also less agreement at local and regional levels.