NASA says climate change may have a huge impact on major crops within 10 years
A new study shows that if current trends continue, climate change could greatly affect corn and wheat production by 2030. Maize yields are expected to fall by 24%, while wheat yields may increase by about 17%. Like rice and soybeans, these crops provide nearly two-thirds of human food consumption, so these changes may have a global impact. The results have been announced In the magazine Natural food.
Scientists have used advanced climate and agricultural models to find that the change in yield is due to the expected increase in temperature, Changes in rainfall patterns, And the increase in atmospheric carbon dioxide concentration caused by man-made greenhouse gas emissions. These changes will make it more difficult to grow corn in tropical areas, but may expand the scope of wheat cultivation.
“Compared with the previous generation of climate and crop model crop yield forecasts conducted in 2014, we did not expect such a fundamental shift,” said the lead author Jonas Jagmeier, NASA’s crop modeler and climate scientist Goddard Institute for Space Research with Columbia University Earth InstituteHe said the expected corn response was unexpectedly large and negative. “A 20% drop from current production levels may have a serious impact on the world,” he said.
A new study claims that due to climate change, global corn production could fall by a quarter as early as 2030. This is a field in upstate New York. (Jesse Gardner/No Splash)
To arrive at their predictions, the research team used two sets of models.First, they use Climate model simulation From the International Climate Model Comparison Project-Phase 6 (CMIP6). Each of the five CMIP6 climate models used in this study runs its own unique response of the Earth’s atmosphere to the 2100 greenhouse gas emission scenario. Because of their different representations of the planetary climate system, these responses are different.
The research team then used climate model simulations as input to 12 state-of-the-art global crop models as part of the agricultural model comparison and improvement project (AgMIP), an international partnership coordinated by Columbia University.this Crop model Large-scale simulation of how crops grow and respond to environmental conditions such as temperature, rainfall, and atmospheric carbon dioxide provided by climate models.The behavior of each crop is based on its Biological reactions in real life Research in indoor and outdoor laboratory experiments.
In the end, the team created approximately 240 global climate crop model simulations for each crop. By using multiple climate and crop models in various combinations, researchers are confident in their results.
“What we are doing is to promote crop simulation, with the support of supercomputers, effectively plant virtual crops every day, and then observe the changes in every part of the world year by year and decade,” said Alex Rohn, A scientist at the Goddard Institute and a co-author of the study.
The research only focuses on climate impacts; these models do not involve economic incentives, changes in farming practices, or adaptability, such as cultivating more cold-tolerant crop varieties, even though this is an area Active researchThe research team plans to study these perspectives in follow-up work, because as people respond to climate-driven changes, they will also determine the fate of future agricultural production.
Soybean and rice forecasts also show regional change patterns, but on a global scale, the overall impact of different models on climate change is still divided. For corn and wheat, the climate effect is much more pronounced, and most model results point in the same direction.
Corn or maize is grown all over the world and is produced in large quantities in countries close to the equator. Maize production in North and Central America, West Africa, Central Asia, Brazil, and China may decline in the next few years, as the average temperature in these granary areas increases, putting more pressure on plants.
Wheat grows best in temperate climates. As temperatures increase, wheat may be grown in wider areas, including the northern United States and southern Canada, the North China Plain, Central Asia, southern Australia, and East Africa. However, these gains may level off in the middle of this century.
Temperature is not the only factor that the model considers when simulating future crop yields. Higher levels of carbon dioxide in the atmosphere have a positive effect on photosynthesis and water retention. This increases crop yield, but usually at the expense of the nutritional value of the crop. Compared with corn, this effect of wheat occurs more often. Global temperature rise is also related to changes in rainfall patterns and the frequency and duration of heat waves and droughts, which affect crop health and productivity. Higher temperatures also affect the length of the growing season and accelerate crop maturity.
“You can think of plants as collecting sunlight throughout the growing season,” Ruane said. “They are collecting energy and putting it in plants and grains. So, if you rush through your growth phase, by the end of the season, you just haven’t collected that much energy.” Therefore, it has a longer period of time. This plant produces less total grain compared to a plant in its developmental stage. “By growing faster, your output will actually fall.”
“Even under an optimistic climate change scenario, society has made ambitious efforts to limit global temperature rise, and global agriculture is also facing a new climate reality,” Jägermeyr said. “Moreover, with the interconnection of the global food system, even the granary in a region will be affected by the world.”
Adapted from a NASA press release.
