Responses of crop yield growth to global temperature and socioeconomic changes

Toshichika Iizumi,Motoki Nishimori,Wonsik Kim,Jun Furuya,Tomoko Hasegawa,Zhihong Shen,Masashi Okada,Shinichiro Fujimori

doi:10.1038/s41598-017-08214-4

Abstract

Although biophysical yield responses to local warming have been studied, we know little about how crop yield growth—a function of climate and technology—responds to global temperature and socioeconomic changes. Here, we present the yield growth of major crops under warming conditions from preindustrial levels as simulated by a global gridded crop model. The results revealed that global mean yields of maize and soybean will stagnate with warming even when agronomic adjustments are considered. This trend is consistent across socioeconomic assumptions. Low-income countries located at low latitudes will benefit from intensive mitigation and from associated limited warming trends (1.8 °C), thus preventing maize, soybean and wheat yield stagnation. Rice yields in these countries can improve under more aggressive warming trends. The yield growth of maize and soybean crops in high-income countries located at mid and high latitudes will stagnate, whereas that of rice and wheat will not. Our findings underpin the importance of ambitious climate mitigation targets for sustaining yield growth worldwide.

Highlights

Given the anticipated increase in food demand in the coming decades, recent and future yield growth levels, including their patterns and rates[1,2,3,4], are of concern to national governments and international agencies focused on agriculture and food security
The combined use of assumptions and crop model outputs is methodologically valid, it has become evident that the climate change that has occurred over the past few decades has had measurable effects on the yield growth and variability of major crops[11,12,13]
The improved correspondence reported here between modeled and reported yields in relative rather than absolute terms is consistent with other crop modeling works

Summary

Introduction

Given the anticipated increase in food demand in the coming decades, recent and future yield growth levels, including their patterns and rates[1,2,3,4], are of concern to national governments and international agencies focused on agriculture and food security. This is despite the fact that the relative contributions of climate change to yields have until now likely been less significant than those of technological improvements and that the negative impacts of past climate change may be offset by fertilizer effects associated with elevated carbon dioxide (CO2) concentrations To this end, attempts to estimate potential future yield growth based on a biophysical crop model would benefit scientific communities in further improving estimates of adaptation costs of agriculture and food security. The impacts of climate change on crop production has considered yield responses to local warming by geographic region[11, 15, 16] This is informative and allows for an understanding of varying yield responses and adaptation potentials across regions, and requires the use of aggregation to infer the responses of global or country mean yields to a specific level of global temperature change, such as 1.5 °C or 2 °C This shortfall can be seen in earlier work, with the notable exception of ref. 18 and, research addressing yield growth responses to various warming levels is needed to fill this knowledge gap

Methods

Results

Conclusion