text: 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. 