According to a new study published in Nature Food, potential climate-related implications on future agricultural productivity are a major societal worry.
Jonas Jägermeyr, lead author and crop modeler and climate scientist at NASA's Goddard Institute for Space Studies (GISS), The Earth Institute at Columbia University in New York City, and the Potsdam Institute for Climate Impact Research (PIK), stated, We are seeing that new climate circumstances are pushing agricultural yields outside of their regular range in an increasing number of places. Human-caused greenhouse gas emissions raise temperatures, cause changes in rainfall patterns, and increase carbon dioxide levels in the atmosphere. This has an impact on crop growth, and we show that the appearance of climate change signals the time when exceptional years become the norm will occur within the next decade or shortly thereafter in several critical breadbasket regions throughout the world. This means that farmers must adjust much more quickly, for example, by shifting planting dates or using various crop varieties, to avoid severe losses while still realizing advantages in higher-latitude regions.
The team of researchers generated the largest ensemble of future yield forecasts as of today by merging a set of new climate projections and numerous state-of-the-art crop models. They discovered major changes in the very near future, as well as across the most key expanding regions. Maize is grown in a variety of latitudes, including subtropical and tropical countries where greater temperatures are more detrimental than in colder high-latitude locations. Maize yields in North and Central America, West Africa, Central, and East Asia could fall by more than 20% in the future years. Wheat, which grows best in temperate temperatures, may see increased productivity in present growing areas as a result of climate change, including the Northern United States and Canada, as well as China.
One effect the data clearly reveal, according to Christoph Müller, co-author, and researcher at the Potsdam Institute is that poorer nations are likely to see the steepest decreases in yields of their primary staple crops. This worsens already-existing disparities in food security and wealth.
Importantly, wheat increases in the North do not compensate for maize losses in the South. Poor countries, as well as the impacted smallholder farmers, frequently lack the financial resources to purchase food on the global market. As a result, the anticipated fundamental shift in agricultural production patterns may pose a risk to food security in some countries while benefiting others.
Temperature is not the sole element influencing agricultural yields in the future. Higher quantities of carbon dioxide in the atmosphere benefit crop development, particularly wheat. It may, however, impair their nutritional value. Rising global temperatures are also associated with changes in rainfall patterns, as well as the frequency and length of heatwaves and droughts, all of which pose threats to crop health and productivity.
According to Jägermeyr, even in hopeful climate change scenarios in which civilizations make strong measures to prevent global temperature rise, global agriculture is confronted with new climate reality.
Journal Information: Jonas Jägermeyr, Climate impacts on global agriculture emerge earlier in new generation of climate and crop models, Nature Food (2021). DOI: 10.1038/s43016-021-00400-y. www.nature.com/articles/s43016-021-00400-y