Agriculture

Agricultural Impacts of Climate Change

Given that crops and livestock thrive in a relatively narrow set of environmental parameters, it makes sense to explore how climate change will affect agricultural productivity. Factors considered include the impacts of rising temperatures, increased production of carbon dioxide and other greenhouse gases, water supply fluctuations, soil quality variations, sea-level increases, and the introduction of new pests, diseases, and weeds, which could hurt agricultural output. These [Page 12]changes can have different impacts depending on the geographic scale of analysis. Climatic change will have different manifestations at local, regional, and global scales. Impacts will also vary according to the agricultural products under consideration. Some plant or animal species may be very resilient to environmental changes. Others may not adapt so well to change.

One of the ways agriculture contributes to greenhouse gases is by shipping produce hundreds of miles to markets.

Temperature increases will affect crop and livestock production in various ways. A warming climate will extend the frost-free growing season at higher latitudes. Regions that are too cold to support commercial agriculture in northern Canada, Alaska, Scandinavia, and Russia, may become viable agricultural areas if temperatures increase. On the other hand, temperature-sensitive crops may no longer be commercially viable in regions that become too hot or dry. Also, rising temperatures could increase the heat stress on livestock.

Climatic change models predict that regional temperature variations may alter precipitation patterns and the supply ofwater for agriculture. Areas that are currently too dry may receive more moisture in the future. Areas that are productive now without irrigation may suffer as temperatures increase, because of increased plant evapo-transpiration. Farmers will have to find ways to offset the rising temperatures and corresponding moisture loss if they are to survive. Furthermore, many meteorologists suggest that weather events such as thunderstorms, tornados, and hurricanes may become more intense and occur with greater frequency. This may bring more rain to some regions. On the other hand, severe storms cause strong winds and flooding, which could cause large-scale crop damage.

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