8 - Effects of Climate Change on Food Production

Summary

Editor's Introduction

Like hunger, the stresses that arise from rapid climate change will fall most heavily on the poorest, the most vulnerable, and those least able to adopt new technology. Food supply is perhaps the arena in which the potential crisis could prove most severe. As Martin Parry and M.S. Swaminathan show in this chapter, global climate change will increase the stress on agricultural systems, potentially decreasing yields at the very time when demand for food is growing dramatically.

This chapter, an overview of the most likely impacts of climate change on food production, emphasizes that current scientific knowledge is insufficient to allow us to predict the regional impacts of climate change on food production with much confidence. The news is not all bad, however. Increased concentrations of carbon dioxide have had a fertilization effect on some crops in the laboratory, when all other environmental conditions have been tightly controlled. Unfortunately, field conditions cannot always be so carefully controlled. And not all plants benefit equally from this effect. Wheat and barley have shown strongly positive effects; corn, a less positive response.

Parry and Swaminathan also note some strong and troubling trends in recent research results. The more pronounced warming in high latitude areas that is predicted by climate models will extend the Northern range of agricultural potential. But it may also decrease grain yields in the core of traditional agricultural areas. In the low-latitude countries, changes in temperature regimes will require farmers to alter crop-timing patterns that have been finetuned over centuries of experience with traditional regional climates.