Climate change will stir up global agriculture within next decade

 A study has predicted "deep changes" in global agriculture within a decade if the current global warming trends continue.

The findings of the study by lead author Jonas Jagermeyr, a 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 at the Potsdam Institute for Climate Impact Research (PIK) were published on the website 'Nature Food'.

As per the study, due to the severe changes the present breadbasket regions across the globe are experiencing, the farmers require to adapt to new climate realities now.

"We see that new climate conditions push crop yields outside of their normal range in more and more regions. Human-made greenhouse gas emissions bring higher temperatures, shifts in rainfall patterns, and more carbon dioxide in the air. This affects crop growth, and we find that the emergence of the climate change signal - the time when extraordinary years become the norm - will occur within the next decade or soon after in many key breadbasket regions globally," explains Jagermeyr.

"This means that farmers need to adapt much faster, for example by changing planting dates or use different crop varieties, to avoid severe losses, but also to realize gains in higher-latitude regions," he added.

The study also revealed a likeliness of decline of maize crop yields by almost a quarter by the end of the century, while that of wheat could potentially see global yield increases of about 17 per cent.

By combining a set of new climate projections and various state-of-the-art crop models, the team of researchers found significant changes already in the very near future, and across the most important growing regions.

The findings of the study reveal: "Maize is grown in a wide range of latitudes, including sub-tropical and tropical countries where higher temperatures will be more harmful than in cooler high-latitude regions. North and Central America, West Africa, Central and East Asia will potentially see maize yields decline by more than 20 per cent in the coming years."

Wheat, which grows best in temperate climates, may, in turn, see productivity increase in current growing areas under climate change, including areas in the Northern United States and Canada, and China, it added.

"One effect the data show clearly is that poorer countries are likely to experience the sharpest declines in yields of their main staple crops. This exacerbates already existing differences in food security and wealth," says Christoph Muller, co-author and also a researcher at the Potsdam Institute.

Further, it was revealed that the wheat gains in the global North do not make up for maize losses in the global South.

"Poor countries and of course the affected smallholder farmers themselves often lack the means to procure food on the world market. The projected fundamental change in agricultural production patterns could hence in some regions become a risk for food security, while others profit," the study read.

As per the study, temperature is not the only factor relevant for future crop yields.

"Higher levels of carbon dioxide in the atmosphere have a positive effect on crop growth, especially for wheat. However, it could also reduce their nutritional value. Rising global temperatures also are linked with changes in rainfall patterns, and the frequency and duration of heatwaves and droughts, which are risks to crop health and productivity," the study revealed.

"Even under optimistic climate change scenarios, where societies put in ambitious efforts to limit global temperature rise, agriculture">global agriculture is facing a new climate reality," Jagermeyr said.

The study titled "Climate change signal in agriculture" emerges earlier in new generation of climate and crop models" on Nature Food has been authored by Jonas Jagermeyr, Christoph Muller, Alex Ruane et al in 2021.