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Vol.:(0123456789)Scientific Reports |        (2022) 12:17268  | https://doi.org/10.1038/s41598-022-22228-7
www.nature.com/scientificreports/
security of the whole world would still be attacked violently. There are huge differences among the continents; 
South America, Asia and the Middle East are threatened seriously by yield loss seriously under global warming 
by 1.5 °C. The changes in maize yield in different regions would influence the maize price and food trades. So, 
it should be cautious to cope with the maize changes under global warming by 1.5 °C.
From the results of simulated by the NorESM1-M model under RCP 4.5 scenario, the gross yield of maize in 
the world between 2060 and 2079 would decrease by 18.7% relative to 1986–2005. The area is 41.7% of the whole 
maize planting regions in the world, in which the yield loss would be less than 50%. The area is 15.6% of the whole 
maize planting regions, in which the yield loss would be more than 50%. The area is 42.7% of the whole maize 
planting regions, in which the yield would increase. The distribution of maize yield change is similar to that under 
global warming by 1.5 °C. From the results simulated by the GFDL-ESM2M model under RCP 6.0 scenario, the 
gross yield of maize in the world between 2065 and 2084 would decrease by 3% relative to 1986–2005. Comparing 
to the results of the NorESM1-M model, the regions of high yield loss rate are increasing, and the regions of yield 
increases are going down; but the per unit area yields are increasing quickly in the regions of yield increasing. So, 
the gross maize yield in the whole world simulated by the GFDL-ESM2M model is more than the NorESM1-M 
model. In a comprehensive perspective, under global warming by 2.0 °C, maize yield in the whole world would 
decrease 10.8% relative to 1986–2005 (Fig. 4). Compared to the results under global warming by 1.5 °C, the risk 
of yield loss is much higher. According to the new results from the Emission Gap Report in 2019, the target of 
global warming by 1.5 °C would not be implemented according to the reality of mitigation actions; the chance 
become much bigger for all countries in the world, who will be facing the severe challenge of global temperature 
rise of 2.0 °C or even higher (3.0 °C or 4.0 °C) in the future. So it is critical to cope with the serious condition 
Figure 4.  Distribution of yield loss rates on maize in the world under global warming by 2.0 °C (up: 
NorESM1-M model, RCP 4.5; down: GFDL-ESM2M model, RCP 6.0). The figure has been generated using 
ArcGIS 10.2 and Natural Earth-Free vector and raster map data @ https:// natur alear thdata. com.