Along with the familiar difficulties related to pests and diseases, potato farmers are increasingly confronted with abiotic problems. Farmers and researchers report an increase in water stress, changes in rainfall distribution and intensity, hail, and increasingly frequent frost and snowfall at high altitudes. The growing frequency of extreme weather events is generally interpreted as clearly related to climate change. The newest report by the Intergovernmental Panel of Climate Change (IPCC), published in 2007, states that global climate warming is an unequivocal fact. Projections by the IPCC predict a rise in global temperature by 1.8?4°C by the year 2100 due to the increase in greenhouse gases, depending on the scenario. This is expected to have grave consequences for mankind and the environment. The critical threshold is said to be around a temperature increase of 2°C.
Approximately 15% of the total worldwide greenhouse gas emissions are caused by agriculture. An additional 11% result from deforestation, mainly for the purpose of gaining cropland. Carbon dioxide (CO2) emissions in agriculture are chiefly caused by the use of fossil fuels during all kinds of agricultural activities, as well as tillage, burning of crop residues, and slash-and-burn deforestation. In addition, agriculture produces around half of the global methane (CH4) and nitrous oxide (N2O) emissions. These two greenhouse gases are many times more potent than carbon dioxide. The main sources of CH4 are livestock production, irrigated rice cultivation, and storage of manure. N2O is released into the atmosphere through the soil following the inadequate application of artificial fertilisers and manure. By taking appropriate measures, agriculture has the possibility of reducing greenhouse gas emissions and thereby actively contributing to the mitigation of climate change.
