Apr 18, 2013
Insight: energy prices will drive global land use in the 21st century
Energy prices are expected to have a profound effect on how land around the world is used over the coming century, according to analysis in Environmental Research Letters (ERL) by a team of researchers at Purdue University in the US. The effect may be larger than that of other well-known drivers, such as climate policies concerning food and biofuels.
The world's land-resource base will undergo many changes over the course of this century as global population continues to increase, the diet of people in developing countries improves, and the demand for biofuels rises. Petroleum and natural gas will compete with biofuels, depending on the price of each type of energy source, and rising energy prices will put significant pressure on global land supply and lead to greenhouse-gas emissions. So understanding and quantifying these key drivers is an important issue for both the scientific community and for policymakers.
We used FABLE (Forest, Agriculture, and Biofuels in a Land use model with Environmental services), a dynamic economic optimization model for the world's land resources. We compared the effects of varying energy prices with the effects of other drivers of land use, as well as to the amount of land-based greenhouse gases emitted over the course of the next century.
Our results showed that the uncertainty in energy prices in 2100 will considerably affect how land is used around the world, and that this effect will be larger than that predicted by existing analyses of global land use, which have largely focused on climate mitigation and energy policies as well as climate impacts.
Despite its limitations, our model suggested that long-term uncertainty in energy price forecasts means that as much as 400 MHa of land will be used differently in the future. This is four times higher than how land use will change as a result of uncertainty in climate affecting agricultural yields, and two times higher than the maximum variation in land-use change from uncertainty in future greenhouse-gas emissions targets.
How the world economy will react to land-use change in the future with respect to changing energy prices is difficult to predict, and involves complex scenarios. For instance, natural-gas prices affect the use of fertilizers, allowing the same volume of crop to be produced on smaller areas of land, and oil prices in the future will determine how economically feasible biofuels will be.
We concluded that the link between energy prices and global land-use change needs to be studied in more detail.
About the author
Jevgenijs Steinbuks is a post-doctoral research associate and Thomas Hertel is a distinguished professor and the director of the Center for Global Trade Analysis in the department of agricultural economics at Purdue University in West Lafayette, Indiana, US. Both authors are currently involved in the National Science Foundation-funded research project on the optimal allocation of global land in the presence of uncertainty and irreversibility co-ordinated by the Center for Robust Decision Making on Climate and Energy Policy at the University of Chicago, US.