Klimawissenschaft – eine Spielart der Physik ?

1. Klimawissenschaft – eine Spielart der Physik? Hans von StorchInstitutfürKüstenforschung

2. Hans von Storch Klimaforscher Spezialgebiet: Küstenklima, also Windstürme, Sturmfluten, Seegang, Nordsee, Ostsee, Nordatlantik Kooperation auch mit Sozial- und Geisteswissenschaftlern Direktor des Instituts für Küstenforschung des Helmholtz Zentrums Geesthacht

4. Overview • Climate Research – history • Physics of Climate • Problems – independence, experiments, inhomogeneity of data, parameterizations • Postnormality – high uncertainty, high stakes • The knowledge market

5. Overview • Climate Research – history • Physics of Climate • Problems – independence, experiments, inhomogeneity of data, parameterizations • Postnormality – high uncertainty, high stakes • The knowledge market

6. Climate research – history • Anthropocentric view – climate determines living conditions; • Climatic determinism • Physics of atmosphere and of ocean • Physics of climate • Climate change – climate constrains living conditions

7. Alexander von Humboldt (1769–1859) Cosmos, A Sketch of a Physical Description of the Universe, 1845 “The term climate, taken in its most general sense, indicates all the changes in the atmosphere, which sensibly affect our organs, as temperature, humidity, variations in the barometrical pressure, the calm state of the air or the action of varying winds, the amount of electric tension, the purity of the atmosphere or its admixture with more or less noxious gaseous exhalations, and, finally, the degree of ordinary transparency and clearness of the sky, which is not only important with respect to the increased radiation from the earth, the organic development of plants, and the ripening of fruits, but also with reference to its influence on the feelings and mental condition of men”.

8. Climatic determinism Ellsworth Huntington 1876–1947 of Yale University climatic energy civilization

9. Atmospheric and oceanic dynamics

10. Climate physics

11. Climate change – climate constrains living conditions policies mitigation, adaptation costs after Hasselmann, 1990

12. Overview • Climate Research – history • Physics of Climate • Problems – independence, experiments, inhomogeneity of data, parameterizations • Postnormality – high uncertainty, high stakes • The knowledge market

13. Global temperature derived from thermometer data (CRU)

14. Nur natürliche Faktoren Auch mensch-gemachte Treibhausgase Messungen Explaining global mean surface air temperature IPCC 2007

15. Scenarios, not predictions

16. Overview • Climate Research – history • Physics of Climate • Problems – independence, experiments, inhomogeneity of data, parameterizations • Postnormality – high uncertainty, high stakes • The knowledge market

17. The space-and time-scales of atmospheric and oceanic dynamics

18. atmosphere

19. Need for parametrising the effect of non-resolved dynamics on the resolved dynamics. e.g., by specifying the expected effect due to small-scale dynamics conditional upon the large scale (resolved) state. Alternative: choose randomly an effect observed under the given large-scale state. The limit x0 is not defined for parameterizations; there is no known limiting equations. Dynamical processes in a global atmospheric general circulation model This part is called physics in the slang of atmospheric and oceanic scientists (as opposed to the revolved dynamics).

20. Data, independent observations, experiments • All data are dependent on each other; maybe every 30 years, or so, we are able to observe a new somewhat independent realization of the climate system. • Only one world, thus truly independent data for falsifying hypotheses is generated at very slow pace. • Real experiments hardly possible (except for in models as virtual realities) • Reliance on past data – instrumental and indirect (proxy)

21. Representativity of near surface wind speed measurements • Causesofinhomogenities: • Changes in • Instruments • Sampling frequencies • Measuringunits • Environments (e.g. trees, buildings) • Location Station relocations (Dottedlines) 1.25 m/s J. Lindenberg, 2010

22. Representativity of near surface wind speed measurements J. Lindenberg, 2010

23. Historical data - inhomogeneity Counting storms in weather maps – steady increase of NE Atlantic storms since the 1930s ….

24. Overview • Climate Research – history • Physics of Climate • Problems – independence, experiments, inhomogeneity of data, parameterizations • Postnormality – high uncertainty, high stakes • The knowledge market

25. Postnormal science facts uncertain: e.g. sensitivity of global mean temperature to doubling of CO2 concentration values in dispute, e.g., do we cement the world according to our present preferences or do we accept a generationally dynamical development? stakes high, e.g., costs for re-organizing global energy market and future damages decisions urgent, e.g., to be efficient, re-organization of e.g., traffic must be begun now. Jerry Ravetz, Silvio Funtovicz, 1986 and earlier State of science, when facts uncertain, values in dispute, stakes high and decisions urgent. In this state, science is not only done for reasons for curiosity but is asked for as support for preconceived value-based agendas.

26. policies mitigation, adaptation costs

28. Overview • Climate Research – history • Physics of Climate • Problems – independence, experiments, inhomogeneity of data, parameterizations • Postnormality – high uncertainty, high stakes • The knowledge market

29. Two different construction of „climate change“ – scientific and cultural – which is more powerful? Cultural: „Klimakatastrophe“ Scientific: man-made change is real, can be mitigated to some extent but not completely avoided Lund and Stockholm Storms

30. The science-.policy/public interaction is not an issue of „knowledge speaks to power“. The problem is not that the public is stupid or uneducated. The problem is that the scientific knowledge is confronted on the „explanation marked“ with other forms of knowledge (pre-scientific, outdated; traditional, morphed by different interests). Scientific knowledge does not necessarily “win” this competition. The social process „science“ is influenced by these other knowledge forms. Science can not be objective but should nevertheless strive to be so. Knowledge market

31. And physics …? • Climate science comprises a large segment which is essential a type of physics • Climate science is of great technical importance, for issues of mitigation and even more so for adaptation – and thus a type of engineering. • But climate science is embedded in a politico-cultural context, which makes climate science post-normal. • Thus climate science as a whole is not “just” another type of physics, but a social process significantly different from conventional physics.

32. ClimateSciences … • … comprise much more issues than the geophysical issues of fluid dynamics and thermodynamics forcing. • Impacts of climate variability and change are in the focus of academic interest, which is driven not only by scientific understanding but also by media constructions and value-basedassumptions. • “Climate” has very much to do with what is culturally believed and understood - both in the public and among scientific actors. • “Climate” must therefore become a field of active social- and cultural research on the functioning of science-society interactions and scientific practice. • Climate Science is much more than Physics.

33. Take home … • The basic physical understanding is not contested (humans > CO2/GHG > warming). • Many secondary effects (e.g., ice sheets, hurricanes) still under analysis. • Regional manifestation and impacts still under analysis. • 2-degree goal is a political goal, not a scientifically determined goal. • Climate science operates under post-normal conditions, i.e., the differences between political actors and scientific actors blurr. • Critical questioning (by skeptics) is legitimate and helpful. • Climate science needs critical analysis by cultural sciences.

34. http://coast.gkss.de/staff/storch hvonstorch@web.de Weblog KLIMAZWIEBEL http://klimazwiebel.blogspot.com/