WGI: The Physical Science Basis - Overview Presentation, Thomas Stocker

1. © Yann Arthus-Bertrand / Altitude
Thomas Stocker & Qin Dahe
Co-Chairs IPCC Working Group I
Switzerland and China
Overview:
Climate Change 2013
The Physical Science Basis

2. www.climatechange2013.org

3. 3
Observations
Understanding
Future

4. Warming of the climate system
is unequivocal
IPCC2013,Fig.SPM.1b,IPCC2014,Fig.1.1
Anomaly(°C)relativeto1961-1990

5. Warming of the climate system
is unequivocal
EnergyContent(1021Joule)
1980 1990 2000 2010
300
200
0
100
-100
1970
70 mill.
TWh
IPCC2014,SYRFig.1.2

6. (Lüthi et al.,2008, NOAA)
+30%
2014
The concentrations of CO2 have increased to levels
unprecedented in at least the last 800,000 years.
1000 years before present
CO2Concentrations(ppm)

7. IPCC2013,Fig.SPM.7,IPCC2014,Fig.SPM.6
Global mean surface temperature change from 1986-2005
Further warming will increase the likelihood of
severe, pervasive and irreversible impacts for
people and ecosystems.

8. IPCC2013,Fig.SPM.8,IPCC2014,Fig.SPM.7
Further warming will increase the likelihood of
severe, pervasive and irreversible impacts for
people and ecosystems.
Change in average surface temperature (1986-2005 to 2081-2100)
RCP8.5

9. IPCC2013,Fig.SPM.8,IPCC2014,Fig.SPM.7
Change in average precipitation (1986-2005 to 2081-2100)
RCP8.5
Further warming will increase the likelihood of
severe, pervasive and irreversible impacts for
people and ecosystems.

10. RCP 2.6 (annual) RCP 8.5 (annual)
IPCC 2013: Atlas of Global and Regional Climate Projections
Changes in South Europe/Mediterranean (2081-2100)

11. Further warming will increase the likelihood of severe,
pervasive and irreversible impacts for people and ecosystems.
IPCC2013,TFE.2,Fig.2
+19 cm
+63 cm

12. Further uptake of carbon by the ocean
will increase ocean acidification.
IPCC2013,Fig.SPM.7c

13. IPCC2013,Fig.SPM.10
790 bill. t C
2°C

14. Budget for the 2°C target: 790 bill t C
CO2 emissions until 2014*: −545 bill t C
CO2 emissions in 2014*: 10.1 bill t C
Remaining emissions: 245 bill t C
*updatedfromIPCC2013,WGISPM
Limiting climate change would require substantial and
sustained reductions in greenhouse gas emissions which,
together with adaptation, can limit climate change risks.

15. 2°C world
IPCC2013,Fig.SPM.8,IPCC2014Fig.SPM.7

16. 4.5°C world2°C world
IPCC2013,Fig.SPM.8,IPCC2014Fig.SPM.7

17. 4.5°C world2°C world
Today we have a choice.