Cash, Crops & Climate

Climate change could hold some surprises for some of the world’s poorest people. Even under scenarios that envision widespread crop failures due to warming, farmers in some poor nations could benefit, according to a new study. The finding highlights how a shifting climate could ripple across the global economy in unexpected ways.

Numerous studies have warned that rising global temperatures could have dire consequences for agriculture, such as increased droughts and declining yields. Relatively few researchers, however, have examined the “domino effect” that changes in farm productivity might have on global trade, economic growth and poverty. In the current issue of Global Environmental Change, Thomas W. Hertel of Purdue University and colleagues at Stanford University in California take a crack at tipping the tiles. Using computer models loaded with real-world economic data from 2001, they examine how poverty rates in 15 developing nations might change under three farm productivity scenarios.

The results from the team’s “moderate” scenario are pretty much in line with past studies that forecast that a temperature rise of one degree Celsius would have relatively modest impacts on world food prices and incomes by 2030. Under the low- and high-productivity scenarios, however, the results are more dramatic. Under the low scenario, prices for staple crops rise by 10% to 60% by 2030, helping push poverty rates up by 20% to 50% among the urban poor in Africa and Asia. The rising prices, however, also lift many poor rural farmers in Latin America and Asia out of poverty, since rising prices mean they earn more from selling their harvests. Overall, poverty drops in eight out of the 15 countries in the low scenario, but the total number of people in poverty still rises by 1.8%. That’s because poor countries with larger populations (such as Bangladesh) are hardest hit. In contrast, many winners and losers trade places in the high-productivity scenario, as the urban poor benefit from low food prices and farmers suffer from stagnating incomes.

The labyrinthine modeling exercise illustrates that understanding climate impacts requires a detailed understanding of farming, “as well as the patterns of trade, production, consumption and poverty in the countries in question,” the authors write. It also highlights the need, they note, for better climate impact models that can tell policymakers “which groups in particular will gain or lose, the reasons why this will happen, and the degree of certainty associated with these estimates.” – David Malakoff

Source: Hertel, T., Burke, M., & Lobell, D. (2010). The poverty implications of climate-induced crop yield changes by 2030. Global Environmental Change DOI: 10.1016/j.gloenvcha.2010.07.001

 Image © Paul Tobeck |