Income Inequality and Carbon Consumption...Motivation and Overview Literature Data and Methodology...
Transcript of Income Inequality and Carbon Consumption...Motivation and Overview Literature Data and Methodology...
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Motivation and Overview Literature Data and Methodology Results Conclusion
Income Inequality and Carbon ConsumptionEvidence from Environmental Engel Curves
(GRI WP 285 & CCCEP WP 319)
Lutz Sager
London School of Economics
A Toxa, 21 June 2018
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Motivation and Overview Literature Data and Methodology Results Conclusion
Motivation: The “equity-pollution” dilemma
Existing literature: Income and carbon
• Income is strong predictor for CO2 footprint (e.g. Chancel &Piketty, 2015)
• BUT Income elasticity < 1 (e.g. Chakravarty et al., 2009)• Necessities are carbon-intensive (e.g. Pearce, 1991)• Regulation / taxation can be regressive (e.g. Poterba, 1991)
The “equity-pollution” dilemma:
Given the higher pollution intensity of consumption per unit ofexpenditure by poorer households, progressive redistribution mayresult in higher aggregate pollution from consumption.
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Motivation and Overview Literature Data and Methodology Results Conclusion
Motivation: The “equity-pollution” dilemma
Existing literature: Income and carbon
• Income is strong predictor for CO2 footprint (e.g. Chancel &Piketty, 2015)
• BUT Income elasticity < 1 (e.g. Chakravarty et al., 2009)• Necessities are carbon-intensive (e.g. Pearce, 1991)• Regulation / taxation can be regressive (e.g. Poterba, 1991)
The “equity-pollution” dilemma:
Given the higher pollution intensity of consumption per unit ofexpenditure by poorer households, progressive redistribution mayresult in higher aggregate pollution from consumption.
![Page 4: Income Inequality and Carbon Consumption...Motivation and Overview Literature Data and Methodology Results Conclusion Income Inequality and Carbon Consumption Evidence from Environmental](https://reader030.fdocuments.us/reader030/viewer/2022040919/5e9536e3d773da3e3e56a2a0/html5/thumbnails/4.jpg)
Motivation and Overview Literature Data and Methodology Results Conclusion
Overview & Contribution
• Estimate GHG content of householdconsumption in United States (1996-2009)
• Estimate Environmental Engel curves (EEC)following Levinson & O’Brien (forthcoming)
• Upward-sloping, Concave, Shifting down• Approximated well by 2nd degree polynomial
• Use parametric EECs to decompose CO2e
between / within time• Quantify the “equity-pollution” dilemma:
• Marginal redistribution: +5.1 per cent in CO2
• Full redistribution: +2.3 per cent• Hypothetical Sweden: +1.5 per cent
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Motivation and Overview Literature Data and Methodology Results Conclusion
Overview & Contribution
• Estimate GHG content of householdconsumption in United States (1996-2009)
• Estimate Environmental Engel curves (EEC)following Levinson & O’Brien (forthcoming)
• Upward-sloping, Concave, Shifting down• Approximated well by 2nd degree polynomial
• Use parametric EECs to decompose CO2e
between / within time• Quantify the “equity-pollution” dilemma:
• Marginal redistribution: +5.1 per cent in CO2
• Full redistribution: +2.3 per cent• Hypothetical Sweden: +1.5 per cent
![Page 6: Income Inequality and Carbon Consumption...Motivation and Overview Literature Data and Methodology Results Conclusion Income Inequality and Carbon Consumption Evidence from Environmental](https://reader030.fdocuments.us/reader030/viewer/2022040919/5e9536e3d773da3e3e56a2a0/html5/thumbnails/6.jpg)
Motivation and Overview Literature Data and Methodology Results Conclusion
Overview & Contribution
• Estimate GHG content of householdconsumption in United States (1996-2009)
• Estimate Environmental Engel curves (EEC)following Levinson & O’Brien (forthcoming)
• Upward-sloping, Concave, Shifting down• Approximated well by 2nd degree polynomial
• Use parametric EECs to decompose CO2e
between / within time
• Quantify the “equity-pollution” dilemma:• Marginal redistribution: +5.1 per cent in CO2
• Full redistribution: +2.3 per cent• Hypothetical Sweden: +1.5 per cent
![Page 7: Income Inequality and Carbon Consumption...Motivation and Overview Literature Data and Methodology Results Conclusion Income Inequality and Carbon Consumption Evidence from Environmental](https://reader030.fdocuments.us/reader030/viewer/2022040919/5e9536e3d773da3e3e56a2a0/html5/thumbnails/7.jpg)
Motivation and Overview Literature Data and Methodology Results Conclusion
Overview & Contribution
• Estimate GHG content of householdconsumption in United States (1996-2009)
• Estimate Environmental Engel curves (EEC)following Levinson & O’Brien (forthcoming)
• Upward-sloping, Concave, Shifting down• Approximated well by 2nd degree polynomial
• Use parametric EECs to decompose CO2e
between / within time• Quantify the “equity-pollution” dilemma:
• Marginal redistribution: +5.1 per cent in CO2
• Full redistribution: +2.3 per cent• Hypothetical Sweden: +1.5 per cent
![Page 8: Income Inequality and Carbon Consumption...Motivation and Overview Literature Data and Methodology Results Conclusion Income Inequality and Carbon Consumption Evidence from Environmental](https://reader030.fdocuments.us/reader030/viewer/2022040919/5e9536e3d773da3e3e56a2a0/html5/thumbnails/8.jpg)
Motivation and Overview Literature Data and Methodology Results Conclusion
Motivation and Overview
Literature
Data and Methodology
Results
Conclusion
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Motivation and Overview Literature Data and Methodology Results Conclusion
Previous literature: Inequality & emissions
Theory: How inequality may a↵ect environmental outcomes
• Political Economy (Boyce, 1994)
• Consumer choice (Scruggs, 1998; Heerink et al., 2001)
Evidence: Association between inequality and emissions
• Baek & Gweisah (2013): positive association(time-series, US, 1967-2008)
• Heerink et al. (2001): negative association(panel, 180 countries, 1961-2001)
• Others; BUT problems of identification for causal inference
Contribution: I estimate the “equity-pollution” dilemmabased on household consumption data within one country(United States).
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Motivation and Overview Literature Data and Methodology Results Conclusion
Previous literature: Inequality & emissions
Theory: How inequality may a↵ect environmental outcomes
• Political Economy (Boyce, 1994)
• Consumer choice (Scruggs, 1998; Heerink et al., 2001)
Evidence: Association between inequality and emissions
• Baek & Gweisah (2013): positive association(time-series, US, 1967-2008)
• Heerink et al. (2001): negative association(panel, 180 countries, 1961-2001)
• Others; BUT problems of identification for causal inference
Contribution: I estimate the “equity-pollution” dilemmabased on household consumption data within one country(United States).
![Page 11: Income Inequality and Carbon Consumption...Motivation and Overview Literature Data and Methodology Results Conclusion Income Inequality and Carbon Consumption Evidence from Environmental](https://reader030.fdocuments.us/reader030/viewer/2022040919/5e9536e3d773da3e3e56a2a0/html5/thumbnails/11.jpg)
Motivation and Overview Literature Data and Methodology Results Conclusion
Previous literature: Inequality & emissions
Theory: How inequality may a↵ect environmental outcomes
• Political Economy (Boyce, 1994)
• Consumer choice (Scruggs, 1998; Heerink et al., 2001)
Evidence: Association between inequality and emissions
• Baek & Gweisah (2013): positive association(time-series, US, 1967-2008)
• Heerink et al. (2001): negative association(panel, 180 countries, 1961-2001)
• Others; BUT problems of identification for causal inference
Contribution: I estimate the “equity-pollution” dilemmabased on household consumption data within one country(United States).
![Page 12: Income Inequality and Carbon Consumption...Motivation and Overview Literature Data and Methodology Results Conclusion Income Inequality and Carbon Consumption Evidence from Environmental](https://reader030.fdocuments.us/reader030/viewer/2022040919/5e9536e3d773da3e3e56a2a0/html5/thumbnails/12.jpg)
Motivation and Overview Literature Data and Methodology Results Conclusion
Data
Data Sources:• U.S. Consumer Expenditure Survey (CEX)
• 51,265 CU (1996 - 2009, yearly)
• World Input-Output Database (WIOD)• Trade flows between 40 countries, 35 sectors• Emissions per sector (CO2, CH4, N2O)
GHG Accounting:
• Input-output based accounting of indirect emissions kgCO2/$• Accounting for global supply chain• Accounting for imported final goods
• Direct emission factors for transport fuels, heating fuels andelectricity
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Motivation and Overview Literature Data and Methodology Results Conclusion
Data
Data Sources:• U.S. Consumer Expenditure Survey (CEX)
• 51,265 CU (1996 - 2009, yearly)
• World Input-Output Database (WIOD)• Trade flows between 40 countries, 35 sectors• Emissions per sector (CO2, CH4, N2O)
GHG Accounting:
• Input-output based accounting of indirect emissions kgCO2/$• Accounting for global supply chain• Accounting for imported final goods
• Direct emission factors for transport fuels, heating fuels andelectricity
![Page 14: Income Inequality and Carbon Consumption...Motivation and Overview Literature Data and Methodology Results Conclusion Income Inequality and Carbon Consumption Evidence from Environmental](https://reader030.fdocuments.us/reader030/viewer/2022040919/5e9536e3d773da3e3e56a2a0/html5/thumbnails/14.jpg)
Motivation and Overview Literature Data and Methodology Results Conclusion
Methodology: From consumption to emissions
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Motivation and Overview Literature Data and Methodology Results Conclusion
Methodology: From consumption to emissions
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Motivation and Overview Literature Data and Methodology Results Conclusion
Methodology: From consumption to emissions
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Motivation and Overview Literature Data and Methodology Results Conclusion
Methodology: From consumption to emissions
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Motivation and Overview Literature Data and Methodology Results Conclusion
Methodology: From consumption to emissions
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Motivation and Overview Literature Data and Methodology Results Conclusion
Final sample
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Motivation and Overview Literature Data and Methodology Results Conclusion
Results: Descriptive Engel curves
1. EECs areincreasing
2. EECs areconcave
3. EECs shift downover time
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Motivation and Overview Literature Data and Methodology Results Conclusion
Results: Descriptive Engel curves
1. EECs areincreasing
2. EECs areconcave
3. EECs shift downover time
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Motivation and Overview Literature Data and Methodology Results Conclusion
Results: Descriptive Engel curves
1. EECs areincreasing
2. EECs areconcave
3. EECs shift downover time
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Motivation and Overview Literature Data and Methodology Results Conclusion
Results: Descriptive Engel curves
1. EECs areincreasing
2. EECs areconcave
3. EECs shift downover time
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Motivation and Overview Literature Data and Methodology Results Conclusion
Results: Technology Improvements
Detail
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Motivation and Overview Literature Data and Methodology Results Conclusion
Results: Parametric Engel curves
Further analyses require additional assumptions:
1. Inclusion of control variables
2. Specific functional form for EEC
3. Assume (conditional) homogeneity of preferences
Empirical specification:
yit = �1tmit + �2tm2
it + x0it�t + ✏it (1)
Household carbon (yit); After tax income (mit); Controls (x0it)
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Motivation and Overview Literature Data and Methodology Results Conclusion
Results: Parametric Engel curves - Estimates
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Motivation and Overview Literature Data and Methodology Results Conclusion
Results: Parametric Engel curves - Estimates
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Motivation and Overview Literature Data and Methodology Results Conclusion
Results: Parametric Engel curves - Quadratic fit
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Motivation and Overview Literature Data and Methodology Results Conclusion
Results: Household carbon - Decomposition over time
Decomposition: Oaxaca-Blinder
• Increase of 11.3t inhousehold carbon between1996 (22.6t) and 2009(33.9t) [2009 technology]
• Income (after tax)explains 3.9t (35 percent)
• Expenditure explains 6.9t(61 per cent)
• Other variables explain little
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Motivation and Overview Literature Data and Methodology Results Conclusion
Results: Household carbon - Decomposition over time
Decomposition: Oaxaca-Blinder
• Increase of 11.3t inhousehold carbon between1996 (22.6t) and 2009(33.9t) [2009 technology]
• Income (after tax)explains 3.9t (35 percent)
• Expenditure explains 6.9t(61 per cent)
• Other variables explain little
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Motivation and Overview Literature Data and Methodology Results Conclusion
Results: Household carbon inequality - Decomposition
Factor decomposition:Shorrocks (1982)
• Income explains31-45 per cent ofvariation in CO2
• Family sizeexplains ca. 13per cent
• Other variablesexplain little
• Large unexplainedvariation
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Motivation and Overview Literature Data and Methodology Results Conclusion
Results: Household carbon inequality - Decomposition
Factor decomposition:Shorrocks (1982)
• Income explains31-45 per cent ofvariation in CO2
• Family sizeexplains ca. 13per cent
• Other variablesexplain little
• Large unexplainedvariation
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Motivation and Overview Literature Data and Methodology Results Conclusion
Results: The “equity-pollution” dilemma
So, by how much would income redistribution increase CO2?
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Motivation and Overview Literature Data and Methodology Results Conclusion
Results: The “equity-pollution” dilemma
Expected e↵ect of marginal transfer between two randomhouseholds:
Eij(@yi@mi
� @yj@mj
|mj > mi) = �2�̂2Eij (mj �mi |mj > mi)
= �2�̂2 (F (m))
Gini’s Mean Di↵erence: (F (m)) =R R
|y � z|dF (y)dF (z) or1
N(N�1)
PN
i=1
PN
j=1|mi � mj |, i 6= j
Di↵erence in emissions when moving to “full equality”:
�̂2
"m2 � 1
N
NX
i=1
m2
i
#
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Motivation and Overview Literature Data and Methodology Results Conclusion
Results: The “equity-pollution” dilemma
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Motivation and Overview Literature Data and Methodology Results Conclusion
Conclusion
• Estimate Environmental Engel Curves (EECs)for CO2e embedded in consumption (UnitedStates, 1996-2009)
• Upward-sloping, Concave, Shifting down• Approximated well by 2nd degree polynomial
• De-compose embedded CO2e between / withintime
• Quantify the “equity-pollution” dilemma:• Marginal redistribution: +5.1 per cent• Full redistribution: +2.3 per cent• Hypothetical Sweden: +1.5 per cent
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Motivation and Overview Literature Data and Methodology Results Conclusion
Thank you!
Comments & Question [email protected]
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Motivation and Overview Literature Data and Methodology Results Conclusion
Appendix: The “equity-pollution” dilemma
Hypothetical Sweden (2009): +1.5 % in CO2 (0.5t per CU)
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Motivation and Overview Literature Data and Methodology Results Conclusion
Appendix: Descriptive Engel curves