全球一半人口到2100年将面临粮食危机

Half of the world's population could face food shortages by the end of this century due to climate change, a new study warned Thursday.

According to researchers, there is a 90 percent probability that by 2100 the minimum temperatures in the tropics and sub-tropical regions will be higher than the maximums so far recorded in those areas.

The effect on crop-growing in those regions would be dire, according to the projections based on direct observations and data culled from 23 computer models on the planet's evolving climate patterns.

"The stresses on global food production from temperature alone are going to be huge, and that doesn't take into account water supplies stressed by the higher temperatures," said David Battisti, a University of Washington atmospheric sciences professor.

In the tropics, the warmest temperatures will cut maize and rice harvests by 20 to 40 percent, the researchers said.

The hotter weather will also reduce the moisture in the soil, cutting yields even further.

Some three billion people, or half the world's population, currently live in tropical and sub-tropical regions, and their number is set to double by the end of the century.

These regions stretch from northern India, southern China to much of Australia and all of Africa, and also extend from the southern United States to northern Argentina and southern Brazil.

一项最新研究于上周四警告称，由于受气候变化的影响，预计到本世纪末全球将有一半的人口面临粮食短缺的威胁。

研究人员称，到2100年，热带和亚热带地区的最低温度将超过这些地区迄今为止出现过的最高温度，出现这一变化的可能性达到90%。

通过直接观察和分析23个全球气候变化模式的计算机模型的数据，研究人员作出预测，气候变化将对这些地区的谷物种植造成十分可怕的影响。

华盛顿大气学教授大卫．巴蒂斯提说：“气温本身对于全球粮食生产的影响将十分巨大，这还没有考虑到高温所导致的水供应的问题。”

研究人员称，极端高温将导致热带地区的玉米和大米产量下降20%至40%。

此外，高温还会减少土壤中的水分，造成粮食产量进一步下降。

目前全球有一半、约30亿的人口居住在热带和亚热带地区，到本世纪末这些地区的人口还将增加一倍。

印度北部、中国南部、澳大利亚大部、非洲全境，美国南部、阿根廷北部以及巴西南部将受到影响。