Transcript Climate Change

Climate Change:
the Swiss Perspective
Dr. Lorenz Martin
Oeschger Centre for Climate Change Research and
Institute of Applied Physics
University of Bern
Climate change is already taking place …
Töss, August 2003
Brienz, August 2005
Prologue
Climate change is already taking place …
(IPCC, 2007)
Prologue
(IPCC, 2007)
Climate change is already taking place …
black: observed temperature anomaly
red: modelled temperature anomaly, with anthropogenic factors
blue: modelled temperature anomaly, without anthropogenic factors
Prologue
Climate change is already taking place …
… and we know why
last 50
years
Siegenthaler et al., (2005)
Joos & Spahni (2008)
last 10‘000
years
last 200
years
Prologue
Outline
Prologue
>
How can we determine the human impact on climate?
>
What will happen with the climate in the future?
>
What can we do against climate change?
Conclusions
The global climate system
How can we determine the human impact on climate?
The greenhouse effect
without greenhouse
effect: -18°C global
average surface
temperature
with greenhouse
effect: 14°C global
average surface
temperature
(Dennis Hartmann)
How can we determine the human impact on climate?
Radiative forcing today
with respect to 1750
How can we determine the human impact on climate?
Excursus: Measuring water vapour
and clouds
>
Water vapour is the most important greenhouse gas
(approx. 65% of the greenhouse effect)
>
The water vapour feedback is approx. 0.5°C/°C
>
Clouds (water and ice droplets) have a strong influence on
the radiation balance in the atmosphere
>
Water vapour and cloud measurements are essential for the
understanding of the climate system and for weather
prediction
How can we determine the human impact on climate?
A new instrument for ground-based water
vapour and cloud measurements
ASMUWARA, the all-sky multi-wavelength radiometer
In operation at the Institute of Applied Physics, Univ. of Bern
How can we determine the human impact on climate?
A new instrument for ground-based water
vapour and cloud measurements
(Martin, 2006)
How can we determine the human impact on climate?
A new instrument for ground-based water
vapour and cloud measurements
MW
above: temperature profiles over Bern
IR
left: multispectral images of clouds
(Martin, 2003)
How can we determine the human impact on climate?
CO2 emission scenarios …
rapid economic growth,
technological changes,
fossil intensive energy
sustainable economies
and societies,
reduced econ. growth
rapid economic growth,
technological changes,
non-fossil energy
(IPCC, 2001)
What will happen with the climate in the future?
… and the expected temperature change
Emissions
(IPCC, 2001)
What will happen with the climate in the future?
… and the expected temperature change
non-fossil
scenario
fossil
scenario
(IPCC, 2007)
What will happen with the climate in the future?
Alpine temperature and humidity
towards 2100
2071-2100 minus 1961-1990 (11 different climate models):
Temperature [ºC]
Precipitation [%]
7
+60
+40
6
+20
5
0
4
3
-40
2
-60
Jan
Mar
May
Jul
Sep
Nov
Jan
(Jacob, 2005)
-20
Mar
May
Jul
=> warm and humid winters, hot and dry summers
What will happen with the climate in the future?
Sep
Nov
What will happen with the climate
in the future? Some examples
(IPCC, 2001)
What will happen with the climate in the future?
Protect or insure?
protect insure
Present Climate
Future Climate
?
?
(Schär, 2004; Heck, SwissRE)
What will happen with the climate in the future?
Melting glaciers and their impact on
river discharge
Seasonal water discharge of river Rhine
at Rheinfelden today and in 2100 (+4.8°C)
What will happen with the climate in the future?
(Shabalova et al 2003)
2003
(Steiner, 2005)
1850
Alpine temperature and humidity
towards 2100
winter
What will happen with the climate in the future?
summer
What can we do against climate change?
Two strategies:
Adaptation (Anpassung)
> adapt to climate change
> typical example: construct river dams against floods
> immediate effect, but local impact
Mitigation (Milderung)
> mitigate climate change
> typical example: use bike instead of car
> global impact, but delayed effect
What can we do against climate change?
The efficiency of regulations …
catalyser in cars in 1986
low-sulphur fuel oil in the 70s
(BFS, BAFU, 2009)
What can we do against climate change?
… and the impact of regulations
on the economy
(OECD, OcCC 2005)
Economic performance is not affected by
environmental regulations, taxes, etc.!
What can we do against climate change?
Conclusions
Climate change is taking place,
and the reasons for climate change are known.
Combating climate change
> costs -- but doing nothing will cost much more!
> requires global cooperation and investments
for the far future.
> is a matter of society, economy and politics.
Every measure (adaptation and mitigation) is helpful.
Conclusions
References
IPCC: International Panel on
Climate Change
part of UNO, founded in 1988
reports approx every 5 years
Working group 1 report 2007:
• 600 authors
• 40 countries
• 600 peer reviewers
http://www.ipcc.ch
Appendix
Climate research in Switzerland and
at the University of Bern
NCCR Climate (http://www.nccr-climate.unibe.ch)
> Swiss centre of excellence for climate research
> start 2001, expected end 2013, NFS funded
> 130 researchers, 13 institutions (Universities, ETH, etc.)
> University of Bern is leading house and coordinator
Oeschger Centre (http://www.oeschger.unibe.ch)
> Climate research centre at the University of Bern
> coordinates, funds and promotes climate research
> interdisciplinary (sciences, humanities, economy, law, …)
> Graduate School of Climate Sciences
Appendix