CARBOOCEAN, Solstrand October 8 2009, Erling Moxnes

Misperceptions of climate change dynamics

Erling Moxnes

Professor in System Dynamics

University of Bergen

Outline

Mental models– Non-communicated assumptions

1. Misperceptions of CO2 accumulation– Laboratory experiments– Information

2. Misperceptions of saturation in absorption– Laboratory experiments– Information

3. Misperceptions of delays– Laboratory experiments– Information

Mental models

• Using 6 matches you should form 4 triangles with equal sides. All triangles should have the same size as the triangle below.

Solution

• Mental model or “theory-in-use”: 2 dimensions• Not communicated: 3 dimensions• Dynamics represent a non-communicated ”third

dimension”

1. Misperceptions of CO2 accumulation

Sketch needed CO2 emissions from 2000 to 2050to reach each of the three desired developments of

anthropogenic CO2 in the atmosphere

Emissions

0

5

10

15

20

1970 1980 1990 2000 2010 2020 2030 2040 2050

?Historical

CO2 in atmosphere

0

100

200

300

400

1970 1980 1990 2000 2010 2020 2030 2040 2050

Historical

Desired 1

Desired 3

Desired 2

Illustrate graphically the relationship between emissions and amount of CO2 in atmospheric

?

Typical emission paths in CO2 tasks

• Pattern matching or

• Correlation

CO2 in atmosphere

0

100

200

300

400

1970 1980 1990 2000 2010 2020 2030 2040 2050

Historical

Desired 1

Desired 3

Desired 2

Typical graphical illustration

Emissions

CO

2 co

ncen

trat

ion

-20

0

20

40

60

80

100

120

140

160

0.00 1.00 2.00 3.00 4.00 5.00 6.00 7.00

CO2 concentration versus emissions, data from 1900 to 1998, correlation coeff.=0.98

“The more emissions the higher concentration and vice versa”

Test of linear instantaneous relationship

Stock=a*Emissions+b

Time

Historical_stock_of_CO21

Correlated_CO2_stock2

1,940 1,950 1,960 1,970 1,980 1,990 2,000

0

50

100

150

200

1 2 1 21 2

1 2

1

2

1

2

1

2

CO2-stock as non-linear function of emissions

-100

-50

0

50

100

150

200

250

0 1 2 3 4 5 6 7 8

Emissions

Test of nonlinear instantaneous relationship

Time

Historical_stock_of_CO21

Auxiliary_hypothesis2

1,940 1,950 1,960 1,970 1,980 1,990 2,000

0

50

100

150

200

12

1 2

1 2

1 2

12

12

1

Stock and flow model

dS/dt = E - S/T

Emissions

Stock of CO2

Residency time

Absorption

1. Explicit about absorption 2. Explicit about accumulation

Time

Simulated_stock_of_CO21

Historical_stock_of_CO22

1,940 1,950 1,960 1,970 1,980 1,990 2,0000

20

40

60

80

100

120

140

160

180

200

1 2 1 21 2

1 2

1 2

1 2

1

Time

Absorption1

Emissions2

1,940 1,950 1,960 1,970 1,980 1,990 2,0000

2

4

6

8

12

1

21

2

1

2

1

2

1

2

1

2

Residency time = 40 years

Test of dynamic model

Important insights

• The instantaneous model is not consistent with the real system

• A simple dynamic model explains history very well

• Absorption is the sum over land and ocean – and is difficult to measure (?)

• Historical absorption can be estimated with high accuracy

A= S/40 years

Policy implications are very different from what most people expect!

Emission paths from dynamic modelCO2 in atmosphere

0

100

200

300

400

1970 1980 1990 2000 2010 2020 2030 2040 2050

Historical

Desired 1

Desired 3

Desired 2

Emissions

0

5

10

15

20

1970 1980 1990 2000 2010 2020 2030 2040 2050

Historical

Absorption? Desired 2

Desired 1

Desired 3

Experiment: design and results

Max.emissions

Desired amount

Results of experiments

• Sterman & Sweeney (2002, 2007)– Little effect of IPCC summary– Little use for information about absorption

• Moxnes & Saysel (2009)– No effect of phase diagram– No effect of balloon analogy– Little use for information about absorption– Effect of “cognitive conflict” and analogy

Cognitive conflict

320

330

340

350

1977 1979 1981 1983 1985 1987

4.5

5.0

5.5

6.0

6.5

CO2 Emissions

ppm Gtons/year

Anthropogenic emissions do not matter?Need for explanation

CO2 Concentration in atmosphere

CO2 emissions

0

1

2

3

4

5

6

7

1970 1975 1980 1985 1990 1995

Gtons C/year

Analogy

Absorption

?

CO2 concentration

320

325

330

335

340

345

350

355

360

1970 1975 1980 1985 1990 1995

Not sufficient to reduce growth in emissionsNot sufficient to stabilize emissions

Conclusion on accumulation

• Information needed– emissions versus– absorption!

• Conceptual change for effect– Challenge instantaneous model– Analogies to explain dynamic model

• Future absorption?

2.Misperceptions of non-linearity in absorption? (or saturation)

Emissions

Stock of CO2

Absorption

f(S)

Example case: Reindeer St.Paul Alaska

0

500

1000

1500

2000

1910 1920 1930 1940 1950

Number of reindeer

Population

Killing

No “tragedy of the commons”

Historical experiences: Canada

The American Society of Mammalogists:

“... urges that the Canadian Government not undertake the introduction of reindeer into Ungava. Before any introduction is seriously considered, those persons involved in any planning are urged to make a thorough study beforehand of the problems of integrating lichen ecology, reindeer biology, and native culture - serious problems that have not been solved to date on any workable scale on the North American continent.''

Example: Reindeer grazing

Grazing per animal

Growth

Number of reindeer

Lichen Grazing

f(L)

0

500

1000

1500

2000

0 200 400 600 800 1000 1200

Herd and lichen grow th [annual takeouts per year]

Lichen density [g/m2]

Median subject in experiment

Source: Moxnes 2004

History

No “tragedy of the commons”

The case of Snøhetta district

Source: Moxnes et al. 2002

Grazing

Growth0

5000

10000

15000

0 200 400 600 800 1000 1200

Herd and lichen growth [annual takeouts per year]

Lichen density [g/m2]

Snøhetta1944-1997

Experts warning

No “tragedy of the commons”

Conclusion non-linearity

• Non-linearity (or saturation)– Accelerating growth in CO2

• Forecasts of absorption needed– IPCC 75 years residency time

• Conceptual change for effect– Challenge instantaneous model– Analogies to explain dynamic model

3.Misperceptions of delays

- and loss of personal welfare even when the “tragedy of the commons” is not present

Simple strategy – no delay

Goal: fullglass

Feedbackcontrol

Simple strategy – with delay

Goal: fullglass

Feedbackcontrol

Nearly perfect analogy for alcohol

Goal: a little drunk

Nearly perfect analogy for alcohol

Goal: a little sober

Mental model: Few think of the stomach as a funnel for alcohol

Experimental results - high school students

Goal

Long delay

Short delay

Verbal in-formation

Cognitiveconflict and analogy

0.4

0.8

1.2

1.6

Average BAC, g/L

0.0

1 2 3 4 5 6 7 815 minute period

Source: Moxnes and Jensen (2009)

Stock and flow diagram

Feedbackcontrol

Alcohol in stomach

Drinking rate

Alcohol in blood

Absorption rate Metabolic rate

Desired alcoholin blood

Simple strategy explains results

0.0

0.4

0.8

1.2

1.6

0 1 2 3 4 5 6 7 8

BAC, g/L

15 minute period

Source: Moxnes and Jensen (2009)

Long delay

Short delay

People dealing with delays

• underestimate lengths of delays (sum)• do not adjust policies for delays• do not learn quickly

– wrong mental model (external factors)– lack of data– infrequent experiences

GHG in atmosphere Heat in atmosphere

Emissions

Emission capacity

In-radiation Out-radiation

InvestmentDiscarding

Absorption

Climate policy

Change in policy

Climate

Desired policy

Acceptable climate

Delays in climate change

Feedback control?

Long delays in stopping growth in GHGs

Challenges caused by delays

• science and expert advice

• awareness of delays

• conceptual change– from events to behaviour to structure

Thank you

References• Moxnes, Erling, 2004. Misperceptions of basic dynamics, the case of

renewable resource management. System Dynamics Review, 20(2), 139-162.

• Moxnes, Erling and Jensen, Lene C., 2009. Drunker than intended; misperceptions and information treatments. Drug and Alcohol Dependence, 105, 63-70.

• Moxnes, Erling and Saysel, Ali Kerem, 2009. Misperceptions of global climate change: information policies. Climatic Change, 93(1-2), 15-37.

• Sterman, J. D., 2008. Economics - Risk communication on climate: Mental models and mass balance. Science, 322(5901), 532-533.

• Sterman, J. D. and Booth Sweeney, L., 2002. Cloudy skies: assessing public understanding of global warming. System Dynamics Review, 18(2), 207-240.

• Sterman, J. D. and Sweeney, L. B., 2007. Understanding public complacency about climate change: adults' mental models of climate change violate conservation of matter. Climatic Change, 80(3-4), 213-238.

More “invisible hands”

Invisible hand takes care of profits (=normal profits)Cost reductions reduce price and structural change

Demand-

-

Emissions-

Other“taxes”

-+

Transport efficiency

- Oil prices-

+

+Green tax

Costs totruckers

Profits totruckers

-+

+Investmentsin new trucks

+

Price of transportation

+

-

Competition

Trucks+

Normalprofits

-

Alternative energy technology policy

Current profit margin is misleadingMust think of technology development as investment

Green tax

Profitmargin

Production+

+

+

Accumulatedproduction

+

Scale+

-

Productioncosts

Learning

Price

Competitorcosts

R&D+

--

-

Example: Photovoltaics

Price of electricity given by competitor costs

Photovoltaic costs drop over time (path dependence)

Source SEMI: http://www.semi.org/en/P039751

Investment perspective

Time before earning money depends on policiesEarly customers with special needsReduce risk by developing many technologies

Cash flow

Time