Future emission scenarios and data provide important basis for researches on climate change impact and adaption, future air quality projection and assessment, the interaction between air pollution and climate change, the synergy pathways of air pollution mitigation and carbon reduction. China is one of the greatest greenhouse gas and air pollutant emitters in the world, and the future emission trends in the context of “carbon peak and carbon neutrality” has become a great concern of scientists and policy makers.

 Scientists at home and abroad have conducted number of studies on China’s future emission scenarios, analyzed the driving factors of the emission changes, designed a series of emission scenarios at the global (including China) and regional scales. Particularly, the scenario model intercomparison project (i.e., ScenarioMIP) for CMIP6 have developed a set of global future emission scenarios and have been widely used in related researches. However, such global emission scenarios are always lack of China’s detailed emission characteristics and control policies, which is difficult to represent China’s complex emission source system and capture its rapid emission decline in recent years. Take the SSP-RCP global emission scenarios developed for CMIP6 as an example, because they do not incorporate China’s strict air pollution control process since the implementation of the “Action Plan of Air Pollution Prevention and Control” in 2013, the emission amounts and relative change ratios of China after 2013 in the scenarios are greatly different from the reality. On the other hand, most of the scenarios developed with local policies by domestic researchers cannot be connected with the global socio-economic pathways (e.g., SSPs) or climate targets (e.g., RCPs). Besides, there is no publicly available emission scenario or data for researchers to use up to now.

In this context, Tsinghua University has developed the Dynamic Projection model for Emissions in China (abbr., DPEC) with the support of the National Natural Science Foundation of China, the Key Research and Development Program of the Ministry of Science and Technology, and the Energy Foundation. The DPEC model aims to dynamically project and assess China’s future emissions (including both greenhouse gases and air pollutants) in the context of socio-economic development, global climate adaption, national carbon peak and carbon neutrality target, synergy pollution mitigation and carbon reduction pathways. Meanwhile, we would share the emission scenarios and data through the cloud platform with the community, to provide basis support for scientific researches and policy makings.  

The major function of the DPEC model is to dynamically simulate China’s future emission trends based on detailed technology turnover process. On the one hand, the DPEC model integrated more than 700 emission sources and their historical technology distribution in the MEIC model (i.e., Multi-resolution Emission Inventory for China). On this basis, the DPEC model could simulate the technology turnover process and calculate the relative emission of each source under future socio-economic developing drivers and control policy scenarios. On the other hand, the DPEC model seamlessly connected with the global integrated assessment model (GCAM-China). Through mapping the future energy demand and supply under the socio-economic pathways (e.g., SSPs) and climate targets (e.g., RCPs) to the detailed technology turnover emission projection models, the DPEC model thereby could dynamically and precisely simulate China’s future emission trends under various socio-economic pathways and climate control scenarios. Finally, through linking with the multi-scale emission inventory reanalysis and data sharing platform, the DPEC model provides gridded China’s emission data under different future scenarios online for the community. The data format is consistent with the data format provided by the MEIC model.

Currently, the DPEC model provides three sets of future emission scenarios and data sets. The first set (v1.0) contains a total of six future emission scenarios, covering the period from 2015 to 2050, consisting of five CMIP6 climate scenarios (i.e., SSP1-26, SSP2-45, SSP3-70, SSP4-60, SSP5-85) and three groups of pollution control scenarios (i.e., Business-As-Usual, BAU; Enhanced-control-policy, ECP; Best-Health-Effect, BHE). The socio-economic developing drivers, climate target constraints, and energy transition pathways of the DPECv1.0 are consistent with the CMIP6 RCP-SSP scenario matrix; while the pollution control scenarios fully consider China’s current and future clean air actions. The three groups of pollution control scenarios, namely the BAU, ECP, BHE in DPECv1.0, are correspond to the Weak, Medium, Strong pollution control scenarios in the CMIP6. The combined six groups of emission scenarios, namely the SSP1-26-BHE, SSP1-26-ECP, SSP2-45-ECP, SSP3-70-BAU, SSP4-60-BAU and SSP5-85-BHE, cover all of the CMIP6 Tier-1 scenarios and part of Tier-2 scenarios. The scenario evaluation shows that the DPEC scenarios could more accurately reproduce China’s emission variations during 2015-2020, and therefore correct the erroneous emission trends of China in the CMIP scenarios (Tong et al., 2020).

The second set (v1.1) contains a total of six future emission scenarios. Compared with the DPECv1.0, the DPECv1.1 adds one China’s carbon neutrality scenario, and extends the time range to 2015-2060 to support researches on China’s future emission changes and impact assessments in the context of China’s carbon peak and carbon neutrality target. The carbon neutrality scenario assumes that China would achieve the carbon neutrality target by 2060, and its CO₂ emission pathway is between the RCP2.6 and RCP1.9 pathway. The six emission scenarios in DPECv1.1 are SSP1-Netrality-BHE, SSP1-19-BHE, SSP1-26-BHE, SSP2-45-BHE, SSP2-45-ECP and SSP4-60-BAU. For ease of understanding, these six scenarios are also named as Ambitious-pollution-Neutral-goal, Ambitious-pollution-1.5°C-goal, Ambitious-pollution-2°C-goal, Ambitious-pollution-NDC-goal, Current-goals and Baseline (Cheng et al., 2021).

The third set (v1.2) contains five emission scenarios, namely early peak-net zero-clean air, on-time peak-net zero-clean air, on-time peak-clean air, clean air and baseline. The social economy of baseline grows naturally under the SSP1 assumption, without considering additional climate or air pollution control policies. On the basis of baseline scenario, the clean air scenario will implement the Best-Health-Effect (BHE) local pollution control by 2060; and the on-time peak-clean air scenario will further deploy carbon reduction measures in 2020-2030, to achieve the carbon peak around 2030. early peak-net zero-clean air and on-time peak-net zero-clean air are two synergistic scenarios that combine carbon peak policies, carbon neutrality target and BHE pollution control measures; besides, early peak-net zero-clean air further intensify carbon reduction policies in 2020-2030 to boost an earlier carbon peak around 2025. Compared with v1.1, the v1.2 database updates the emission base year to 2020, corresponding to MEICv1.4. DPEC v1.2 also provides a more detailed description of China’s short-term carbon emission reduction policies for 2020-2030 (Cheng et al., 2023).

The DPEC emission scenarios and datasets (including v1.0, v1.1 and v1.2) can be downloaded through the multi-scale emission inventory reanalysis and data sharing platform. Registered users of the MEIC website can download the relevant scenario data after logging in. Welcome to use DPEC emission scenarios and datasets, and provide valuable comments. The MEIC team welcomes any form of data exchange and cooperation. If you have any suggestions or questions, please contact with meic@tsinghua.edu.cn. We hope to cooperate with the scientific community to develop the DPEC model into an open big data platform for the dynamic assessments of China’s future emissions and the relevant impacts.

Features >

• Elaborately simulate China’s future emission technology evolutions and emission trends under different socio-economic scenarios and climate targets, based on detailed technology turnover models.
• Dynamically simulate China’s future emission trends under different combinations of socio-economic scenarios, climate target constraints, energy transition pathways, and pollution control policy.   
• Provide China’s future emission scenarios and datasets linked to the CMIP6 RCP-SSP scenario matrix.
• Provide China’s future emission scenarios and datasets linked to China’s carbon peak and carbon neutrality targets.
• DPEC emission datasets cover nearly 2,000 anthropogenic emission sources in the past and future, including nine air pollutants (i.e., SO₂, NO_x, CO, NMVOC, NH₃, PM_2.5, PM₁₀, BC, OC) and carbon dioxide emissions in China from 2015 to 2060.
• Provide online calculation and download of gridded emission data through the cloud computing platform and big data technology.

Histories >

The DPEC model and scenarios were developed since 2015. Three versions are available at present, and they are continuously under updating.

• Version v1.0 was completed in 2019. In this version, the basic framework of the DPEC model was established; and six groups of emission scenarios (v1.0) linked to the CMIP6 climate scenarios were developed.
• Version v1.1 was completed in 2021. In this version, the cement and steel industries were updated to the facility-level emission projection models, sub-models for key industries in GCAM-China were developed; and six groups of emission scenarios (v1.1) linked to China’s carbon neutrality target were developed;
• Version v1.2 was completed in 2023. In this version, the emission base year was updated to 2020, and provided a more detailed description of China’s short-term carbon emission reduction policies for 2020-2030. Five groups of emission scenarios incorporating China’s carbon peak, carbon neutrality, and air pollution control policies were developed.

Supporting organizations >

The development and maintenance of the DPEC model and scenarios are sponsored by:

• National Natural Science Foundation of China
• Key Research and Development Program of the Ministry of Science and Technology
• Energy Foundation China
• Institute for Carbon Neutrality, Tsinghua University
• State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex
• Ministry of Education Key Laboratory for Earth System Modeling