Global Emission Scenarios and Regional Allocation
The global emission scenario from IPAC mainly comes from the IPAC-Emission global model, with recent studies focusing on global mitigation scenarios. Here, a 2-degree scenario was developed based on the IPAC 450 ppm emission scenario model, as shown in Fig. 2.2. A simplified climate model, MAGICC, was used to set up the CO2 concentration at 450 ppm by year 2100 (Wigley and Raper 2001).
Regional allocation of emissions from the global emission scenario was given by using the 'burden-sharing' method. There are several ways to share the burden of emission reduction, and the subject itself has attracted much political discussion as regards whether to base it on emission per capita convergence, accumulated emission per capita convergence or something else. Sidestepping the politics, the method we used is the widely used model based on the per capita emission convergence method. With the global emission scenario from the global model, regional emission allocation was performed using CO2 emission per capita convergence criteria.
Table 2.1 Production of selected energy-intensive products
Source: Author's research result
Fig. 2.2 Global CO2 emissions at 450 ppm by 2100 (Source: Author's research result)
When burden sharing using emission per capita is analysed, certain assumptions are made:
– Year to reach emission per capita convergence: here, we use 2070.
– Annex 1 countries will start reduction based on the Kyoto commitment and then proceed to deep reductions. Non-Annex 1 countries will start to depart from baseline emissions from 2010.
– CO2 emission per capita in some developing countries may exceed developed countries.
– Population in IPAC model comes from IIASA analysis. Figure 2.3 gives the CO2 emissions by major regions and countries.
Fig. 2.3 Emissions in regions based on per capita emission convergence burden sharing (Source: Author's research result)
In order to allow more leeway for the emissions of developing countries in the future, developed countries need to make deep reductions as soon as possible. In the analysis, we also assumed other developing countries will do their part in CO2 mitigation, based on country developments and international collaboration.
The technological feasibility was also considered, which was based on the global emission scenario study from IPAC model. Figure 2.3 presents a picture for emission reduction in 2020 towards the 2-degree target.
China's Emission Scenarios
The IPAC team developed and published emission scenarios for China (Kejun et al. 2008, 2009), which comprise the three scenarios: baseline, low carbon and enhanced low carbon. The enhanced low-carbon (ELC) scenario involves China peaking in CO2 emissions by 2030 and then starting to decrease after that.
From Fig. 2.3, we can see China's CO2 emissions peaking at around 2025 at 8.56 billion tonnes, in order to reach the global 2-degree target. This is tougher than the enhanced low-carbon scenario from IPAC. With the assumption on GDP, the carbon intensity from 2005 to 2020 will be in the range of 49–59 % for these scenarios, which is much higher than the government target announced.
The government target announced based on a 40–45 % carbon intensity reduction between 2005 and 2020 is realised via domestic efforts. On the one hand, it is possible for China to do better if existing policies on energy efficiency, renewable energy and nuclear energy continue over the next two Five-Year Plans but with more emphasis placed on low-carbon development and low-carbon transport and
Fig. 2.4 CO2 emission scenario in China (Source: Author's research result)
lifestyle; on the other hand, it is also possible to go further with international collaboration via technology collaboration, international carbon financing, carbon market and so on. Basically, the possibility for China to do better is high.
In order to analyse the feasibility for China, one more scenario—the 2-degree scenario for China—was given using the same model. Under this modelling analysis, we can see economic activities, energy activities, technology progress and lifestyle change in much more detail. The 2-degree scenario was developed based on the enhanced low-carbon scenario by pursuing further action in order to assess the feasibility.
Figure 2.4 presents the results for the new scenario family.