Mitigating greenhouse gas emissions in hard-to-abate sectors

For the last sector, the difficulty lies mainly in the granularity of the sector with many actors involved and site-specific conditions, while, in the other sectors, there are technical limitations in bringing emissions to zero on a sectoral level. [...] In addition, it provides context to the model analysis, by using the identified policies and measures in developing the scenarios and in the interpretation of the model projections. [...] The key components of the human system that largely contribute to greenhouse gas emissions are the energy system and the agricultural and land systems. [...] The socio-economic processes and most of the human system parameters are described at the level of 26 world regions, while the earth system is modelled on a 5x5 minute grid for land use and land-use changes and on a 30x30 minute grid for plant growth and the carbon and water cycles. [...] The continuing intensification and expansion of the agricultural sector, associated with increases in the use of synthetic fertilizer and manure production, is the primary driver of the increase in N2O emissions.