Climate Change: the Swiss Perspective Dr. Lorenz Martin Oeschger Centre for Climate Change Research and Institute of Applied Physics University of Bern

Prologue Climate change is already taking place … Töss, August 2003 Brienz, August 2005

Prologue Climate change is already taking place … (IPCC, 2007)

Prologue Climate change is already taking place … (IPCC, 2007) 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 Siegenthaler et al., (2005) Joos & Spahni (2008) last 10‘000 years last 200 years last 50 years

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

How can we determine the human impact on climate? The global climate system

How can we determine the human impact on climate? The greenhouse effect (Dennis Hartmann) without greenhouse effect: -18°C global average surface temperature with greenhouse effect: 14°C global average surface temperature

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 above: temperature profiles over Bern left: multispectral images of clouds MW IR (Martin, 2003)

What will happen with the climate in the future? CO 2 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 (IPCC, 2007) non-fossil scenario fossil scenario

What will happen with the climate in the future? Alpine temperature and humidity towards minus (11 different climate models): Temperature [ºC] JanMarMayJulSepNov Precipitation [%] JanMarMayJulSepNov (Jacob, 2005) => warm and humid winters, hot and dry summers

What will happen with the climate in the future? 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? Present Climate Future Climate ?? protect insure (Schär, 2004; Heck, SwissRE)

What will happen with the climate in the future? Melting glaciers and their impact on river discharge (Shabalova et al 2003) Seasonal water discharge of river Rhine at Rheinfelden today and in 2100 (+4.8°C) (Steiner, 2005)

What will happen with the climate in the future? Alpine temperature and humidity towards 2100 wintersummer

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 Economic performance is not affected by environmental regulations, taxes, etc.! (OECD, OcCC 2005)

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.

Appendix 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

Appendix Climate research in Switzerland and at the University of Bern NCCR Climate ( > 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 ( > Climate research centre at the University of Bern > coordinates, funds and promotes climate research > interdisciplinary (sciences, humanities, economy, law, …) > Graduate School of Climate Sciences