This report looks at the impact which large-scale agrofuel production is likely to have on the global climate through agriculture and ecosystem destruction. It discusses the different sources of greenhouse gas emissions linked to the cultivation and refining of agrofuel feedstocks as well as the impact on overall fossil fuel consumption.
Particular emphasis is put on the direct and secondary impacts of agrofuel expansion on the world’s terrestrial carbon sinks, particularly those in the tropics and subtropics. Crops grown for agrofuels can lead to the destruction of carbon sinks such as rainforests either because forests are directly converted to ‘energy crops’, or because other types of agricultural activities are displaced and pushed into forests and other important ecosystems.
Global warming is primarily a severe disturbance of the carbon cycle. On the one hand, humans are putting about 8 billion tones of carbon into the atmosphere every year. On the other hand, ecosystems are rapidly being destroyed and degraded. Ecosystems, including healthy soils, play an essential role in regulating the climate, by sequestering and storing carbon, by regulating the nitrogen cycle, by contributing to cloud formation, convection and thus regulating rainfall, and by maintaining the hydrological cycle. Ecosystem destruction is linked to 1-3 billion tonnes of carbon emissions per year, and it also causes significant regional warming as well as destabilizing the climate system in a highly unpredictable way.
The Stern Review stresses that total emissions from land use will be greater, because there is no global estimate for soil carbon emissions as a result of agriculture and land-use change. Furthermore, neither the Stern Review, nor any of the IPCC Assessment Reports published to date, estimates global emissions from peat oxidation and fires.
Different types and sources of greenhouse gas emissions linked to agriculture and land-use change, and the impact of large-scale agrofuel expansion are examined.

By: A. Boswell, A. Ernsting, D. Rughani

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