emissions and 52% of N2O emissions in the EU. The role of agriculture both as a source of and as a sink for GHGs varies significantly across the NAE region because of the differ­ent agricultural policies and practices. Emissions also come from changes in forests and other woody biomass stocks, forest and grassland conversions and from the soil (IPCC, 2000b; UNESCO, 2006a). There is a clear trend across the whole NAE region to boost efforts to decrease emissions by replacing fossil fuels with liquid biofuels (IEA, 2006).
     The effects of climate change on agriculture (including forestry and fisheries) are already visible in different parts of NAE (IPCC, 2007b). During the 20th century, for instance, as a result of spring and summer warming and a shorter pe­riod of snow, the thermal growing season (with daily mean temperatures above 5°C) was lengthened by about ten days in southern Finland (Carter, 2007).

5.4.6.2 Uncertainties for the future

How might GHG emissions develop in the future?
There are a number of uncertainties involved in predicting the future development of GHG emissions (IPCC, 2000a). Some of the uncertainties relate to economic development, energy supply and use as well as consumer behavior around the world (Sachs, 2006; EC, 2007). Other uncertainties re-

late to the operation of the carbon cycle which is crucial in translating emissions into concentrations as well as the mag­nitude and behavior of vulnerable carbon pools (UNESCO, 2006a; IPCC, 2007a): Natural carbon pools could well turn into sources as global warming and deforestation continue. Some of the most vulnerable pools are (1) carbon in frozen soils, (2) carbon in cold and tropical peatlands, and (3) bio-mass-carbon in forests vulnerable to fire and insect infesta­tions. Within the time span of our assessment (up to 2050) most of the IPCC emission scenarios are indistinguishable because of the inertia in our economic and technological systems. Furthermore, and as a result of this and the inertia also in the climate system, climate projections in the NAE region until 2050 are quite similar.

Possible evolution of NAE climate and possible consequences for agriculture
Climate projections indicate that annual temperatures over Europe will continue to warm at a rate of between 0.1 and 0.4° C per decade. The greatest increases are expected over southern Europe and northeast Europe (Parry, 2000). Higher temperatures will increase evaporation from plants and soil, worsening the water problems that already afflict the hotter (southern) regions of NAE. Annual precipitation is expected to increase by 1-2% per decade-1 in northern Europe. There