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According to Nature Food, potential climate-related effects on future crop yields are a significant concern for society.
"We are seeing that crop yields in new climate conditions push them out of their normal range in increasing numbers of regions. Climate change is a result of human-made greenhouse gas emissions. This causes higher temperatures and shifts in rainfall patterns. It also increases carbon dioxide levels in the atmosphere. We find this affects crop growth and that the emergenceof the climate change signal, the time when extraordinary years will become the norm in many key breadbasket areas globally, will occur within the next ten years or shortly after. Jonas Jgermeyr is a climate scientist and crop modeler at NASA's Goddard Institute for Space Studies, The Earth Institute at Columbia University, New York City and the Potsdam Institute for Climate Impact Research. This means that farmers must adapt faster to avoid serious losses and to make gains in higher-latitude areas.
Wheat yields up, maize yields less
The team of researchers combined a number of climate projections with various crop models to create the largest collection of future yield projections. The team of researchers found that there were significant changes in the near future and across all important regions. Maize can be grown at a variety of latitudes. It is also grown in sub-tropical or tropical countries, where the higher temperatures are more dangerous than those in lower-latitude areas. In the next few years, maize yields could drop by up to 20% in North, Central America, West Africa and Central and East Asia. Wheat, which thrives in warm climates, could see its productivity rise in current areas that are growing under climate change. This includes areas in North America, Canada, and China.
Existing inequalities are being exacerbated
"The data clearly show that the yields of main staple crops in poor countries will experience the greatest declines. This is a clear effect. Christoph Mller, coauthor and researcher at the Potsdam Institute, says that this will exacerbate already existing food security and wealth disparities. Importantly, maize losses in Global South are not compensated by wheat gains in the Global North. The poor countries, and the smallholder farmers who are most affected by the changes in agricultural production patterns, often lack the ability to access the global market for food. Some regions could be at risk from the projected fundamental shift in agricultural production patterns, while others may benefit.
Future crop yields are not only affected by temperature. A higher level of carbon dioxide in the atmosphere has a positive impact on crop growth, particularly wheat. It could, however, reduce their nutritional value. Global warming is also linked to changes in rainfall patterns and the duration and frequency of heat waves, which can have a negative impact on crop productivity and health. Jgermeyr stated that even under optimistic climate change scenarios where societies make great efforts to limit global temperatures rise, global agriculture faces a new climate reality.
Jonas Jgermeyr provides more information, Climate impacts on global agricultural production emerge earlier in Nature Food (2021) climate and crop model developments. www.nature.com/articles/s43016-021-00400-y Journal information: Nature Food Jonas Jgermeyr, Climate impacts on global agriculture emerge earlier in new generation of climate and crop models,(2021). DOI: 10.1038/s43016-021-00400-y
