climate change and crop productivity

Climate change threatens to increase crop losses, increase the number of people facing malnutrition, or worse, and may change the development patterns of animal diseases and plant pests, the United Nations agricultural agency says in a new report.

The UN Food and Agriculture Organization (FAO), in collaboration with the International Institute of Applied Systems Analysis (IIASA), has developed the Agro-Ecological Zones (AEZ) methodology, a worldwide spatial soil and climate suitability database for use in quantifying regional impacts and geographical shifts in agricultural land and productivity potentials.
Using this data, FAO says in the report, presented during the 31st session of the Committee on World Food Security, that the northern industrialized countries could increase their crop production potential as a result of climate change.

On the other hand, "in some 40 poor, developing countries, with a combined population of 2 billion, including 450 million undernourished people, production losses due to climate change may drastically increase the number of undernourished people, severely hindering progress in combating poverty and food insecurity," the report says.

Sixty-five developing countries, home to more than half the developing world's total population in 1995, risk losing about 280 million tons of potential cereal production, valued at $56 billion, as a result of climate change. This loss would be equivalent to 16 per cent of the agricultural gross domestic product (GDP) of these countries in 1995 dollars, it adds.

Among these countries, India could lose 125 million tons, or 18 per cent, of its rainfed cereal production, while China’s rainfed cereal production of 350 million tons is expected to rise by 15 per cent, it says.

In Africa, 1.1 billion hectares of land have a growing period of less than 120 days, it says. By 2080 climate change could result in an expansion of this area by 5 to 8 per cent, or by about 50 to 90 million hectares, FAO says.