The publication of the Stern Review on the Economics of Climate Change in 2006 and the Fourth Assessment Report by the Intergovernmental Panel on Climate Change (IPCC) in 2007 have pushed the scientific and public debate on
climate change a decisive step forward. It is now beyond doubt that anthropogenic greenhouse gas (GHG) emissions are the main cause for recently observed climate change and that early and bold mitigation measures will eventually be much cheaper than later adaptation to potentially drastic climate impacts. The agricultural sector is
directly affected by changes in temperature, precipitation, and CO2 concentrations in the atmo- sphere, but it is also contributing about one-third to total GHG emissions, mainly through live- stock and rice production, nitrogen fertilization, and tropical deforestation. Agriculture currently accounts for 5% of world economic output, em-
ploys 22% of the global workforce, and occupies 40% of the total land area. In the developing countries, about 70% of the population lives in rural areas, where agriculture is the largest supporter of livelihoods. In many developing countries, the economy is heavily depending on agriculture. The sector accounts for 40% of gross domestic product (GDP) in Africa and 28% in South Asia. However, in the future, agriculture will have to compete for scarce land and water resources with growing urban areas and industrial production.