1. The IPCC future: Representative Concentrations Pathways (RCP)
CICERO lunch seminar
The IPCC future: Representative Concentrations Pathways (RCP)
Asbjørn Aaheim
November 30th, 2011

2. Exploring the role of adaptation
Why new scenarios?
More detailed information needed to run the current generation of climate models
Enable an explicit exploration of the impact of different climate policies, and comparisons with non- climate-policy scenarios
Exploring the role of adaptation
Take full advantage of recent developments of integrated models
Scenarios ought to better reflect policy alternatives: Max and min emission paths, paths in between that distinguish policy alternatives, stabilization of concentrations, declining concentrations, extended horizon
Extended applicability of scenarios

3. Main characteristics of RCPs
Four marker scenarios named after radiative forcing at stabilization (with exceptions)
Detailed scenarios, including land use, to 2100 – general paths to 2300
Each marker RCP produced by separate models
RCP3: IMAGE
RCP4.5: GCAM
RCP6: AIM
RCP8.5: MESSAGE
Unit
2000
2100
RCP3
RCP4.5
RCP6
RCP8.5
Population
bill
6.0
9.0
8.5
9.8
12.6
World GDP
1012 US$ 30
363
365
218
191
Primary energy EJ
475
855
1150
830
1750
Population, rather than economic development, drives energy use

4. Global emissions of carbon by RCP

5. Nitrous oxide
Methane

6. Quotas of constant annual, allowable CO2 emissions until 2100 in RCP 4
Quotas of constant annual, allowable CO2 emissions until 2100 in RCP 4.5 (approx 2.5 °C) with same total emissions (orange) and same contribution to forcing in 2100 (yellow) by region. Percent of present emissions
Kilde: RCP4.5

7. Preliminary climate scenarios: CMIP5 – a ”small” climate model
(Meinshausen 2010)
Year
RCP8.5
RCP 4.5
Low
Most likely
High
2050
1.8
2.1
3.0
1.6
2.5
2100
3.6
4.7
6.5
1.9
2.4
3.5
2150
4.8
8.6
2.0
3.7
Stabilized
5.8
8.0
>10
2.6
4.1
Change in precipitation not available

8. Global mean temperature in RCP4.5 – Max Planck Institute IMPLICC
dT (2006 – 2100): ; dT +2.41

9. A climate policy analysis: Costs and benefits

10. Representation of impacts in GRACE
Adjust energy use for heating and cooling
Tourism
Vector-born diseases
Damage from natural hazards
Soil
productivity
Runoff

11. BNP etter region ved
RCP8.5
RCP4.5

12. The storylines: Shared socioeconomic pathways (SSP)
Rich, equal and resource demanding
Continuation of current dynamics
SSP5
SSP3
SSP2
Challenges to mitigation
SSP1
SSP4
The world of the few, cynical rich
Cooperation, equity and development
Challenges to adaptation

13. Read more: Climatic Change special issue – online August 2011
van Vuuren, D.P. et al. (2011): «A proposal for a new scenario framwork to support research and assessment in different climate research communities», Global Environmental Change – online
RCPs are found on