Transcript The uptake, transport and storage of anthropogenic CO2 by

Science, policy, and politics
of global climate change
Results from WS'06 survey
Nicolas Gruber
Environmental Physics, Institute of Biogeochemistry and Pollutant Dynamics,
ETH Zürich, Switzerland
Questionnaire
1. How large do you think was the observed global
surface temperature increase from 1900 to 2000?
Average: 0.9 ± 0.4 °C
Range: 0.4 - 1.5 °C
Questionnaire (cont)
2. How strongly are you convinced that the observed warming
in the 20th century is due, in part, to human influences
(1: not convinced; 5 strongly convinced)
Average: 4.6 ± 0.5
Range: 4 - 5
Questionnaire (cont)
3. Which evidence do you find most convincing do demonstrate this human
influence (up to three choices possible)
a.
b.
c.
d.
e.
f.
g.
h.
i.
j.
Instrumental temperature record (14)
Satellite temperature record (6)
Proxy temperature reconstruction for the last 1000 years (18)
Retreat of tropical glaciers (8)
Detection studies with models (1)
Sea-ice retreat (3)
Antarctic shelf-ice breakup (10)
Stratospheric cooling (0)
Day-night warming pattern (0)
Your favorite choice (name) (5) CO2 record
Global change: Ice-sheet breakdown
January 31, 2002
Larsen ice-sheet in Antarctica
March 5, 2002
Global change: Glacier retreat
ca 1850
Rhone glacier
2004
Global change: Glacier retreat
2004
~1900
2004
2004
Rhone glacier in Switzerland
Questionnaire (cont)
4.
Please rank the following components to radiative forcing in terms
of their contribution to global warming. Do one ranking for now and
one for what you think the situation will be in 50 years from now?
TODAY
a.
b.
c.
d.
e.
f.
CO2 (33)
CH4 (20)
CFCs (10)
Aerosols (direct) (6)
Aerosols (indirect) (5)
Solar forcing (3)
FUTURE
a.
b.
c.
d.
e.
f.
CO2 (26)
CH4 (20)
CFCs (3)
Aerosols (direct) (4)
Aerosols (indirect) (7)
Solar forcing (5)
Note: water vapour is not considered a radiative forcing
Questionnaire (cont)
5. How much different do you expect global mean temperature to be in
2030, 2050 and 2100 in comparison to now?
Average:
Range:
2030
2050
2100
0.7 ± 0.5
0.05 to 1.5
1.6 ± 1.5
0.5 to 6
2.8 ± 1.8
0.7 to 6.5
Projected warming (2071-2100)
Projected changes in precipitation
Questionnaire (cont)
6. What do you think will be the primary driver(s) for setting this
temperature (rank 1-3)?
a.
Population changes (14)
b.
Economic development (16)
c.
Technological development (16)
d.
Earth system feedbacks (28)
What determines future climate?
∆T = g · ∆cCO2atm
g
∆cCO2atm
climate sensitivity (function of feedbacks)
future atmospheric CO2 concentration
∆cCO2atm = ƒ(E · fair)
E
ƒair
Anthropogenic CO2 emissions
airborne fraction (function of carbon system feedbacks)
E= Npop · renergy · ICO2
Npop
renergy
ICO2
Population
Energy consumption per capita
CO2 intensity of energy source
What determines future climate?
∆T = g · ƒ(fair · Npop · renergy · ICO2)
physical climate system (feedbacks)
bgc climate system (bgc feedbacks)
Socio-economic factors (health, education, etc)
Economical-political-technical factors
Technical/economical factors
OUR CHOICE
We have a choice!
Questionnaire (cont)
7.
How do you rank the importance of global climate change
vs. these other problems?
a.
Climate Change (17)
b.
HIV/Aids (5)
c.
Malnutrition (29)
d.
Sanitation and Water (31)
e.
Migration (2)
f.
Terrorism (0)
Ranking by the Copenhagen Consenus
Questionnaire (cont)
8.
Do you think we know enough in order to act upon the issue
of global warming?
a.
b.
c.
d.
Science is unsettled, need to do more research before
acting (1)
Scientific evidence is relatively clear, but we have other
priorities (1)
Scientific evidence is relatively clear, and we should act
even in the presence of other important issues. (12)
Scientific evidence is unsettled, but we should act now
regardless. (0)
Questionnaire (cont)
9.
What do you view as the most effective role of scientists in this
debate?
a.
Write peer reviewed articles and rely on the public to pick up
the information (1)
b.
Give public lectures, write essays for the general public (11)
c.
Get involved in IPCC (2)
d.
Become a scientific activist (0)
Policy versus Politics
Policy: Prudence or wisdom in the management affairs or highlevel plan embracing the general goals and acceptable
procedures
Politics: Art or science of government or art or science of guiding
government policies.
IPCC mandate: policy guiding but not prescriptive!
The role of science and scientists
• Public obligation versus academic freedom (curiosity driven research)
• Academic standing versus activism
• Science policy versus scientific politics
Questionnaire (cont)
10. If (physical) climate scientists had another 1 B $ at hand, what
would you spend it on?
a.
Climate observations (1)
b.
Process studies (6)
c.
Model development and scenario testing (2)
d.
Method development (4)
e.
Something else (please specify) (1) lobbying