Presentation by Thomas Stocker during IPCC Outreach Event, Nairobi, Kenya (23 February 2015)

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

2. Key SPM Messages
19 Headlines
on less than 2 Pages
2
14 Chapters & Atlas
1,100,000 Words
Summary for Policymakers
14,000 Words

3. Human influence on the
climate system is clear.
Continued GHG emissions will
cause further warming and
amplify existing risks.
Changes in climate have
caused impacts in natural
and human systems.
Multiple pathways exist to likely
limit warming to below 2°C.

4. 4
Observations
Understanding
Future

5. Warming of the climate system
is unequivocal
IPCC2013,Fig.SPM.1b
Temperature Difference 1901 to 2012 based on trend (°C)

6. Warming of the climate system
is unequivocal
IPCC2013,Fig.SPM.2
Precipitation Difference 1951 to 2010 based on trend (mm/yr per decade)

7. Warming of the climate system
is unequivocal
IPCC2013,Fig.SPM.2
Precipitation Difference 1951 to 2010 based on trend (mm/yr per decade)

8. atmosphere, land, ocean
extreme events
global water cycle
global mean sea level
Human influence on the
climate system is clear.
sea ice, glaciers, ice sheets
Cause
Worldwide Effects

9. IPCC2013,Fig.SPM.7a
Global mean surface temperature change from 1986-2005
Continued emissions will cause further warming and
changes in all components of the climate system.

10. IPCC2013,Fig.SPM.8a
Continued emissions will cause further warming and
changes in all components of the climate system.
Change in average surface temperature (1986-2005 to 2081-2100)
RCP8.5

11. RCP 2.6 (annual) RCP 8.5 (annual)
IPCC 2013: Atlas of Global and Regional Climate Projections
Changes in East Africa (2081-2100)

12. IPCC2012,Fig.SPM.4A
A 1-in-20 year hottest day is likely to become a
1-in-2 year event by the end of the 21st century
 10 more frequent

13. Warming of 0.8 to 2.5°C
1000 billion tons of carbon
Any climate target implies
a limited carbon budget

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

15. Budget for 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
Limiting climate change will require substantial and
sustained reductions of greenhouse gas emissions.
* updated from WGI SPM

16. 2°C world

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