Research Institute of Innovative
Technology for the EarthGlobal Scenario for CO2 and GHG Emissions
November 25, 2011
Systems Analysis Group, RITE,

1. Introduction
RITE has been developing comprehensive scenarios toward sustainable development and climate stabilization
since FY2007 as a part of the “International Research Promotion Program for Global Environment,” which is
supported by the Japanese government (The ALPS project; ALternative Pathways toward Sustainable
development and climate stabilization).1)-4) In this paper, the developed CO2 and GHG emission scenarios byusing a global GHG mitigation model6), 7) (see Appendix) is outlined. This scenario was developed in FY2010
based on the medium socioeconomic scenario (Scenario A)5) of the ALPS Project where latest economic
conditions are taken into account.

2. Global CO2 and GHG emission scenarios
The developed scenario for CO2 and GHG emissions in this paper is a baseline scenario (scenario without
GHG mitigation policy).
2.1 Global energy-related CO2 emission scenario
Figure 1 shows the energy-related CO2 emission scenario by world major country / region. The world total
emission in the year 2008 was 38 Gton-CO2/yr. For future, increase in emission is expected to continue by ouranalysis: emission in the year 2020 is 38Gton-CO2/yr, emission in the year 2050 is 57Gton-CO2/yr. Temporaryemission reductions are observed in developed countries by the influence of the economic crisis that started in
2008, but the impact on the growing trend of global emission is not large.
As shown in Figure 2, regional emission shares changed substantially from the year 1990 to the year 2008.
This change will become larger toward the year 2050 and the share of emissions from Annex I countries who
have legal obligation of emission reduction under the Kyoto Protocol including Japan will become smaller. The
share of the emissions from those countries will be smaller in the year 2020 than a quarter (23%) in the world.
Therefore, it is important to promote the Copenhagen Accord that demands participation of all of the major
emitters for achieving effective CO2 emission reduction.

1

Research Institute of Innovative
Technology for the Earth

Energy-related CO2 Emission [MtCO2/yr]

60000

Other Non-Annex I
countries
Brazil

50000

Korea
40000

India
China

30000

Other Annex Icountries
Japan20000

EU27(+12)
EU15

10000

United States
01990

2000

2010

2020

2030

2040

2050

Figure 1 Energy-related CO2 emission scenario by world major countries / regions(Historical data from 1990 to 2008 are from IEA8))

Note) CO2 emissions from international aviation/marine bunkers and land use, land use change, and forestry (LULUCF) are not included.
Other NonAnnex Icountries
Brazil 17%
1%
Korea
1%
India
3%

United States
24%

China
11%

India
5%

United States
20%

EU15
11%

EU27(+12)
2%
China
23%

EU27(+12)
5%

Other Annex Icountries
11%

Japan
5%

2020

2050
United States
17%Japan4%United States
14% EU158%

EU159%

Brazil
1%
Korea
2%
India
6%

2008

Brazil
1%
Korea
2%

EU1515%

Other Annex I
countries
18%
Other NonAnnex Icountries
23%

Other NonAnnex I
countries
21%

1990

China
28%

EU27(+12)2%
Japan
Brazil
3%
1% Korea
1%
Other Annex I
countries9%

EU27(+12)
3%

Other NonAnnex I
countries
29%

Japan
1%

China
25%

Other Annex I
countries
7%

India
11%

Figure 2 Share of energy-related CO2 emission（1990 and 2008:IEA8）, 2020 and 2050:RITE estimation）
Note) CO2 emissions from international aviation/marine bunkers and land use, land use change, and forestry (LULUCF) are not included.

2Research Institute of Innovative
Technology for the Earth

2.2 Global GHG emission scenario
Figure 3 shows GHG emission scenarios by world major country / region. Increase in GHG emission is also
expected as well as energy-related CO2 emission: emission in the year 2020 is 55Gton-CO2eq/yr, emission in theyear 2050 is 78Gton-CO2eq/yr.
Figure 4 shows regional shares of GHG emission in the world and the share of “other Non-Annex I countries”
is a little larger for GHG than for energy-related CO2 emission. Correspondingly, the share of Annex I countries,
who have legal obligation under the Kyoto Protocol, is slightly decreased (22%) in the year 2020 as comparedwith the share of energy-related CO2 emission. This is due to large emission of agricultural CH4 and N2O inother Non-Annex I countries.

GHG emission [MtCO2eq/yr]

80000

70000

Other Non-Annex Icountries
Brazil

60000

Korea
India

50000
China

40000
30000

Other Annex Icountries
Japan20000

EU27(+12)
EU1510000

United States01990

2000

Figure 32010

2020

2030

2040

2050

GHG emission scenario by world major country / region（Historical data are from UNFCCC9）for Annex I countries and from IEA8) for Non-Annex I countries)
Note) GHG emissions from international aviation/marine bunkers and land use, land use change, and forestry (LULUCF) are not included.

3

Research Institute of Innovative
Technology for the Earth

Other NonAnnex I
countries
23%

United States
19%

Brazil
2%
Korea
1%
India
4%

Other NonAnnex Icountries
27%

China
12%

Other Annex Icountries
18%

India
8%

2005
United States
19%

EU1511%

EU1513%EU27(+12)
4%Brazil
3%Korea
1%Japan
4%

India
5%EU27(+12)
2%
Japan
4%
China
20%

2050

2020
United States
14%
EU159%EU27(+12)
2%Japan2%

Brazil
3%

Korea
1%

Other NonAnnex Icountries
25%

1990

China
26%

Other Annex Icountries
8%

Other NonAnnex Icountries
33%

Other Annex Icountries
10%

United States
12% EU15
7% EU27(+12)
2%
Japan
1%
Other Annex Icountries
7%

Brazil
2% Korea

China
24%

1%
India
11%

Figure 4 Share of GHG emission(1990 and 2005:UNFCCC

9）for Annex I countries and IEA8）for Non-Annex I countries, 2020 and 2050:RITEestimation)Note) GHG emissions from international aviation/marine bunkers and land use, land use change, and forestry (LULUCF) are not included.

References
1) RITE; ALPS project annual report 2007 (in Japanese),
http://www.rite.or.jp/Japanese/h19seikahoukoku/h19ichiran-hyou.htm (2007)
2) RITE; ALPS project annual report 2008 (in Japanese)
http://www.rite.or.jp/Japanese/h20seikahoukoku/h20ichiran-hyou0.html (2008)
3) RITE; ALPS project annual report 2009 (in Japanese)
http://www.rite.or.jp/Japanese/h21seikahoukoku/h21ichiran-hyou.html (2009)
4) RITE; ALPS project annual report 2010 (in Japanese)
http://www.rite.or.jp/Japanese/h22seikahoukoku/h22ichiran-hyou.html (2010)
5) RITE; Development of Long-term Socioeconomic Scenarios –Population, GDPhttp://www.rite.or.jp/Japanese/labo/sysken/research/alps/baselinescenario/E-ScenarioOutline_POPGDP_201
10815.pdf (2011)
6) RITE; RITE GHG Mitigation Assessment Model,
http://www.rite.or.jp/Japanese/labo/sysken/about-global-warming/download-data/RITE_GHGMitigationAss
essmentModel_20090529.pdf (2009)
7) K. Akimoto et al., “Estimates of GHG emission reduction potential by country, sector, and cost”, Energy
Policy, Vol.38, Issue 7, pp.3384-3393 (2010)8) IEA, CO2 emissions from fuel combustion, OECD/IEA (2010)9) UNFCCC, GHG data from UNFCCC, http://unfccc.int/ghg_data/ghg_data_unfccc/items/4146.php (LastAccess; 8th, August 2011)4

Research Institute of Innovative
Technology for the EarthAppendix: Outline of GHG mitigation model of RITE
The global GHG mitigation model6), 7) consists of 3 modules; 1) Principal Assessment Model DNE21+, forenergy-related CO2, 2) Non-energy CO2 emission scenario, that assumes specific non-energy CO2 emissions
independent of mitigation levels of energy-related CO2 emissions, 3) Non-CO2 GHG Assessment Model, for 5
kinds of GHG emissions of the Kyoto Protocol (Figure A-1).

1. DNE 21+ Model

Non-Energy CO2Emissions Scenario

2. Non-CO2 GHG
Assessment Model• Assessment model forenergy-related CO2emissions• 54 regions in theworld• Bottom-up modeling(About 300 specifictechnologies aremodeled)• Projection module fornon-energy CO2emissions• 54 regions in theworld• Estimations ofsectoral non-energyCO2 emissions to beconsistent with GDPand production
activities• Assessment model forthe 5 non-CO2 GHGemissions (CH4, N2O,HFCs, PFC, SF6)
• 18 regions in theworld (Afterwards, finer
allocation is conducted
to 54 regions, basedon the historical data)• The methodology issimilar to the USEPA
assessment

Estimates of the 6 GHG emissions, emission reduction costs
and potentials, and specific cost-effective measures foremission reductions
Figure A-1 Outline of GHG mitigation model
DNE21+ model is an optimization type liner programming model, minimizing the total worldwide energy
system costs over all the assessment period (up to FY 2050).
Figure A-2 shows outline of energy flows in DNE21+ model. The energy supply sectors are connected to theenergy end-use sectors, energy export/import are considered, and the lifetimes of facilities are taken into account,so that assessments are made while maintaining complete consistency across the energy supply & demand sides.
Base on the Scenario A, which is a long-term socioeconomic scenario5) developed in ALPS project, service
demand scenarios (e.g., the production amount of crude steel in Iron & Steel sector, the traffic amount in thetransportation sector) are bottom-upped for sectors (energy-intensive industrial sectors, road transportation
sectors and some equipments in residential & commercial sectors), and other remaining sectors are top-downed
and their energy demands are exogenously assumed. The model solves the best mix of technologies to meet thesedemand scenarios. Here, costs and energy efficiencies of individual technologies used in both the energy supply
sectors and the end-use sectors are explicitly modeled. So, detail evaluation of technologies is conducted and thisis one of the salient features of our model. As another feature of the model, the fine regional segregation (theworld is divided into 54 regions in country level.) is noted because it enables to analyze with regional differencesin consideration (e.g., potentials of renewable energy).

5Research Institute of Innovative
Technology for the EarthIndustry

Fossil fuels
Coal
Oil (conventional, unconv.)
Gas (conventional, unconv.)

Energy conv.
processes(oil refinery, coalgasification, bioethanol, gas
reforming, waterelectrolysis etc.)

Unit
production
cost

Iron & steel
CementPaper & pulp
Chemical (ethylene, propylene,ammonia)

Aluminum
Cumulative production

Solid, liquid and gaseous fuels, andelectricity <Top-down modeling>

Renewable energies
Hydro power & geothermalWind power
Photovoltaics
Biomass

ElectricPowergeneration

Unit
supplycost

Transport
vehicleSolid, liquid and gaseous fuels, andelectricity <Top-down modeling>

Residential & commercial
Annual production

CCS

Refrigerator, TV, air conditioner
etc.
Solid, liquid and gaseous fuels, andelectricity <Top-down modeling>

Nuclear power

Figure A-2

Outline of energy flows in DNE21+ model

For non-energy CO2 emission, one specific scenario is developed based on historical data of UNFCCC andIEA and the cement production scenario which is used in DNE21+ model.
The Non-CO2 GHG model has been developed based on the studies by US EPA with some adjustments bylatest historical data. The regional baseline emissions (emissions without GHG mitigation policy) were estimatedfor five gases: CH4 in seven sectors, N2O in six sectors, HFCs in one sector, PFC in one sector and SF 6 in onesector. The emission reduction is calculated by using elasticity representing the relationship between non-CO2
GHG mitigation ratio relative to the baseline emissions and marginal abatement costs based on the database foremission reduction amounts and reduction costs of individual measures in non-CO2 GHG mitigation. So, themodel is not a direct bottom-up model; however, marginal costs and potentials of non-CO2 GHG mitigation are
eventually based on the bottom-up analysis of the US EPA.
This is the model outline. More information is available in references 6) and 7). CO2 emissions frominternational aviation/marine bunkers and land use, land use change, and forestry (LULUCF) are not evaluated inthis model. So, these emissions are not included in the emission scenario in this paper.

■ CO2 and GHG emission scenarios update
Let us note that this paper may be occasionally updated without notice so that the latest information
on historical emissions, economic trends and energy prices can be reflected in the scenario.
Contact to:
Kohko Tokushige, Fuminori Sano, Keigo Akimoto
Systems Analysis Group
Research Institute of Innovative Technology for the Earth (RITE)
9-2 Kizugawadai, Kizugawa-shi Kyoto 619-0292 JAPAN
PHONE: +81-774-75-2304, FAX: +81-774-75-2317, E-mail：sysinfo@rite.or.jp

6