This Maplecroft map was in the Guardian today, identifying “ those countries which may be susceptible to famine and societal unrest stemming from food shortages and price fluctuations. This map shows the results of evaluating the availability, access and stability of food supplies in 197 countries, as well as the nutritional and health status of populations” (Source)

More information is available on Maplecroft’s site: http://maplecroft.com/about/news/food_security_risk_index_2013.html

It would be interesting to find out a little more the data they used and the assumptions built into this. These data are at the national scale, but I think highly urbanized areas are at greater risk of societal unrest as a result of food shortages and price fluctuations. The countries identified as highest risk are not countries with high levels of urbanisation.