Global food prices and the terms of trade

Agflation refers to a sustained increase in the general price of foodstuffs and in recent years we have become accustomed to seeing the prices of many basic staple products rising. The era of cheap food looks to be over for now on the back of significant demand-side factors, not least rising population levels, higher per capita incomes and speculative demand for foods as prices have become more volatile. Supply-side factors are also important in explaining strong inflation in food prices. Both sides of the market are discussed by Ambrose Evans-Pritchard in his column in the Telegraph today “Food will never be so cheap again” - plenty of applied microeconomics here in addition to the huge number of macroeconomic issues that the trend rise in food prices has caused. One of the big changes in a switch in the terms of trade away from food importers towards food exporters. But do higher food prices necessarily cause agricultural supply to expand?