The climate changes now widely understood to be underway will seriously disrupt agriculture, and they will disrupt most severely those farms that are least flexible in their cropping patterns and uses of technology. Climate change may be the Achilles heel of many of the industrialized farms that now characterize much of agriculture in the developed world. There is a contradictory viewpoint. We have heard some argue that increased carbon dioxide in the atmosphere will feed plant growth and reduce moisture stress on plants, and will therefore be good for yields. This is based on simple plant growth theory and on research undertaken largely in laboratory conditions.
Most scientists are skeptical.
They note that although carbon dioxide alone increases plant growth, the combined effect of carbon dioxide and other factors such as higher temperatures and rainfall variation and weed and insect adaptations may more than offset any increase due to carbon dioxide enrichment. For example, if carbon dioxide increases the total leaf surface area of a plant, the plant may require more water even though its water loss per square inch of leaf area is smaller. The more carbon dioxide in the air, the less tolerant plants seem to be to either high or low temperatures. Also, plants will require more nitrogen fertilizer to make use of increased carbon dioxide in the air. There is also reason to believe that plants may adapt to higher levels of carbon dioxide by reverting to lower rates of photosynthesis, and that plants raised in this condition will suffer reduced protein content, be less palatable, and store less well.