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Vol:.(1234567890)Scientific Reports |        (2022) 12:17268  | https://doi.org/10.1038/s41598-022-22228-7
www.nature.com/scientificreports/
Market price of maize in main countries. In this study, we elaborate on the endogenous response of our 
economic models. This response can be theoretically elaborated as: due to the effect of climate change on yield 
reduction (improvement), the supply curve moves leftward (rightward), reducing (increasing) production and 
raising (lowering) prices. In response, the consumers decrease (increase) their consumption of more expensive 
(cheaper) crops and shifting to other (increase the use of the same) crops. Producers, at the same time, respond 
by changing farm-level management practices and increasing (decreasing) the amount of acreage under these 
crops. At a global scale, the reallocation of production and consumption through international trade further 
alters climate change impacts on global agriculture. This also alters the self-sufficiency ratios of each country/
region due to climate change.
In response to production changes, the price of each commodity changes under both scenarios. At the global 
level, the market price for maize would increase by 0.7% and 3.4% under 1.5 °C scenario and 2.0 °C scenario, 
respectively, which would vary quite largely among different countries and regions under both climate change 
scenarios (Fig.  7). Particularly, the market price would increase by around 22% and 27% in Iran under 2.0 °C 
scenario and 1.5 °C scenario, respectively. Iran is also the region where the highest yield reduction is observed 
due to climate change. Market prices for maize in India, Mexico, Russia, South Africa and the Rest of Africa 
would decrease significantly under both scenarios, as their yields improve due to climate effects. Along with the 
domestic production, the climate change will also induce changes in international trade of maize, resulting in 
changing levels of self-sufficiency ratios (SSR) for each country/region. By SSR, we mean the ratio of domestically 
produced commodity, to the sum of net imports and domestic production. In our scenario analysis, generally, 
the countries that face positive effects on yields and/or are relatively less dependent on imports, are positively 
(less negatively) affected by climate change. For example, maize SSR for Ukraine, India, Russia and Mexico would 
improve under both scenarios (Fig. 8). Whereas the self-sufficiency ratios of maize for Southeast Asia, Bangladesh 
and Iran will worsen under both scenarios. China’s SSR for maize stays almost similar to the level as the baseline.
Discussion and conclusion
Discussion. Our analysis highlights the effects of climate change on global- and regional-specific maize 
yields and the associated economic consequences in 1.5 °C and 2.0 °C -warming scenarios. We find that the 
reduction risk of maize yield under global warming by 2.0 °C is much more serious than that under global warm-
ing by 1.5 °C. On the one hand, the larger the temperature rise, the greater the evapotranspiration would be. 
Although the precipitation is also increasing, the evapotranspiration would become more intense. The limitation 
of water supply for maize growth leads to the decline of yield. On the other hand, relative to global warming by 
1.5 °C, maize production would be faced with more serious and frequent extreme climate events, such as drought 
and heat waves, which would increase the risk of corn yield reduction under global warming by 2.0 °C. In the 
Figure 6.  Yield loss rates on maize in 6 continents under global warming by 1.5 °C and 2.0 °C.