Ven. Bhikkhu Bodhi
Last month, the international relief agency Oxfam issued a briefing entitled Extreme Weather, Extreme Prices, which deals with the impact of extreme weather events on global food prices. The briefing, a summary of a longer research report, makes an important distinction between two kinds of effects that climate change will have on food production as our planet grows ever warmer. The first, the one with which agronomists and climate scientists have primarily been concerned, is the incremental decline in average crop yields caused by gradual increases in global temperature and changes in precipitation patterns.
As temperature rises to a certain optimal range, crop yields rise proportionally until a peak is reached, at which point, with further increases in temperature, they start to decline. Studies of rice harvests in the Philippines, for example, show that for each degree Celsius rise in temperature above the optimum during the growing season, yields of rice decrease by 10%. A similar pattern has been noted for other staples. Drops in production inevitably cause food prices to escalate. Research suggests that the average price of staples such as corn could more than double over the next twenty years, with up to half the increase due to changes in average temperatures and rainfall patterns.