Transcript Climate research – history

Klimawissenschaft
– eine Spielart der
Physik?
Hans von Storch
Institut für
Küstenforschung
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
Overview
• Climate Research – history
• Physics of Climate
• Problems – independence, experiments,
inhomogeneity of data, parameterizations
• Postnormality – high uncertainty, high stakes
• The knowledge market
Overview
• Climate Research – history
• Physics of Climate
• Problems – independence, experiments,
inhomogeneity of data, parameterizations
• Postnormality – high uncertainty, high stakes
• The knowledge market
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
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”.
Climatic determinism
Ellsworth Huntington
1876–1947
climatic energy
of Yale University
civilization
Atmospheric and
oceanic dynamics
Climate physics
Climate change –
climate constrains living conditions
policies
mitigation, adaptation costs
after Hasselmann, 1990
Overview
• Climate Research – history
• Physics of Climate
• Problems – independence, experiments,
inhomogeneity of data, parameterizations
• Postnormality – high uncertainty, high stakes
• The knowledge market
Global temperature derived
from thermometer data (CRU)
Explaining global mean surface air temperature
Nur natürliche
Faktoren
Auch menschgemachte
Treibhausgase
Messungen
IPCC 2007
Scenarios, not predictions
Overview
• Climate Research – history
• Physics of Climate
• Problems – independence, experiments,
inhomogeneity of data, parameterizations
• Postnormality – high uncertainty, high stakes
• The knowledge market
The space-and time-scales of atmospheric and oceanic
dynamics
atmosphere
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.
Dynamical processes in a global atmospheric
general circulation model
The limit x0 is not defined for
parameterizations; there is no
known limiting equations.
This part is called physics in the slang of atmospheric and oceanic scientists
(as opposed to the revolved dynamics).
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)
Representativity of near surface wind speed
measurements
• Causes of inhomogenities:
• Changes in
– Instruments
– Sampling frequencies
– Measuring units
1.25
m/s – Environments (e.g.
trees, buildings)
– Location
Station relocations
(Dotted lines)
J. Lindenberg, 2010
Representativity of near surface wind speed
measurements
J. Lindenberg, 2010
Historical data - inhomogeneity
Counting storms in weather maps – steady increase of NE Atlantic storms since the 1930s ….
Overview
• Climate Research – history
• Physics of Climate
• Problems – independence, experiments,
inhomogeneity of data, parameterizations
• Postnormality – high uncertainty, high stakes
• The knowledge market
Postnormal science
Jerry Ravetz, Silvio
Funtovicz, 1986 and earlier
facts uncertain: e.g. sensitivity
of global mean temperature to
doubling of CO2 concentration
State of science, when facts
uncertain, values in dispute,
stakes high and decisions
urgent.
values in dispute, e.g., do we
cement the world according to
our present preferences or do
we accept a generationally
dynamical development?
In this state, science is not
only done for reasons for
curiosity but is asked for as
support for preconceived
value-based agendas.
stakes high, e.g., costs for reorganizing global energy
market and future damages
decisions urgent, e.g., to be
efficient, re-organization of
e.g., traffic must be begun now.
policies
mitigation, adaptation costs
Overview
• Climate Research – history
• Physics of Climate
• Problems – independence, experiments,
inhomogeneity of data, parameterizations
• Postnormality – high uncertainty, high stakes
• The knowledge market
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
Knowledge market
• 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.
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.
Climate Sciences …
• … 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-based assumptions.
• “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 socialand cultural research on the functioning of sciencesociety interactions and scientific practice.
• Climate Science is much more than Physics.
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.
http://coast.gkss.de/staff/storch
[email protected]
Weblog KLIMAZWIEBEL
http://klimazwiebel.blogspot.com/