RCP 8.5 and some suggestions
for follow-up IAMC activities
Keywan Riahi, Volker Krey, Shilpa Rao,
Vadim Chirkov, Peter Kolp, Nebojsa Nakicenovic
International Institute for Applied System Analysis (IIASA)

IAMC Workshop, NIES, Tsukuba, September 15

RCP 8.5
Primary Energy (World)

GHG Emissions & Pollutants
SOx Emissions

CO2 Emissions
PgSO2

MtC

120.000

RCP 8.5

30.000100.000
25.00080.00020.000

RCP 6.0

RCP 6.0

15.00060.00010.00040.000

RCP 4.5

RCP 8.5

RCP 4.5

5.000

20.000

RCP 3PD (2.6)
RCP 3PD (2.6)-5.00000
2190208020702060205020402030202020102005202000

0.0000.000
2000 2010 2020 2030 2040 2050 2060 2070 2080 2090 2100

Progress on RCP 8.5
 Regional, sectoral, and spatial emissions
 Regional and spatial land-cover Smooth transition from the past (1850-2100) for
pollutant emissions and reactive gases(Lamarque et al) Harmonization of land-cover across RCPs andtransition from 1750 to 2100 (Hurtt et al)• Under preparation:– Harmonization of other GHG emissions andconcentrations– Extension to 2300

Extensions to 2300

Meinshausen et alRCP Selection• RCPs primarily selected to span a wide
range of GHG emissions, concentrations,and forcings for climate modelingexperiments• Focus of each RCP team was to develop
an internally consistent pathway, based on
own socio-economic, demographic,
technology, and other model assumptions

CO2 Emissions (World)
30.000

RCP 8.5
What does it take?
Costs?
Technologies?
LandClimate feedbacks
Etc..
RCP 6.0

25.00015.00010.000-5.00000
2190
2080
2070
2060
2050
2040
2030
20

20

202020

RCP 3PD (2.6)
100.000
05

RCP 4.500

5.00020MtC

20.000CO2 Emissions (World)
30.000

RCP 8.5
25.000Baselines

20.00015.000MtC

RCP 6.0

10.000

00
2190
2080
2070
2060
2050
2040
20302020

20

20

20

-5.00020

RCP 3PD (2.6)
100.000
05

RCP 4.500

5.000

Baseline Assumptions
Population

GDP

14

10billion

88.5
6.0
2.6
4.5

6trillion US$2000

12400

350

2.6300

4.5
6.0
8.5

250

200

150

4100
250

002000 2010 2020 2030 2040 2050 2060 2070 2080 2090 2100

2000 2010 2020 2030 2040 2050 2060 2070 2080 2090 2100

Climate characteristics were the only criteria for the selection of individual RCPs

CO2 Emissions (World)
Additional scenarios needed:
1) To bracket uncertainties
30.0002) Enhance comparability across RCP levels
3) Address critical IAM questions
4) Provide 25.000
Input to the IAV community

RCP 8.5

20.00015.000

RCP 6.0

10.0005.000

RCP 4.50.000-5.00000
2190
2080
2070
2060
2050
2040
2030202020

102005202000

RCP 3PD (2.6)

An Initial Activity• Collect recently developed scenarios, eg:– 2.6 feasibility studies: ADAM, IMAGE/MESSAGE– EMF-22– IPCC Renewables Report– Etc..

• Establish reporting standards (protocols, definitions) thatcan be shared for alternative studies• Development of a “Post-RCP” scenario database (eg forIAM-IAM and IAM-IAV exchange)– Including socioeconomic and technology specific information– Fully interactive and automized• for IAMC modeling teams to upload/download scenario data
• evolutionary growing and thus maintained by the community– Quality check routines (eg, central climate model)

Modeling Comparison Projects• “Second-best” scenarios– Non-participation (EMF22)– Technology (uncertainty and possible failure)• Explore feasibility of targets and costs without eg
CCS/nuclear• Negative emissions technologies– Explore synergies and trade-offs with other policy
priorities:• Energy Security• Energy Access• Hunger• Etc…

Attainability and costs of stabilization depends on
the available technology options
Energy System Costs

Discounted Energy System Costs
1990-2100 (trillion US$2000)

50
No-BECS

49

BECS

48

No-CCS

47
46
45
44
43
42
41
40
300

400

500
ppmv CO2

Riahi, 2004600