Climate change and global inequality
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Climate change and global inequality Marshall Burke Department of Earth System Science Center on Food Security and the Environment Stanford University Reducing Inequality in a Sustainable World Conference Berkeley, Mar 5 2015 [With thanks to co-authors Sol Hsiang and Ted Miguel (Berkeley)]
Transcript of Climate change and global inequality
Climate change and global inequality
Marshall Burke!Department of Earth System Science Center on Food Security and the Environment Stanford University !!Reducing Inequality in a Sustainable World Conference Berkeley, Mar 5 2015 !![With thanks to co-authors Sol Hsiang and Ted Miguel (Berkeley)]
Impact of climate change
Impact of climate change
Main question: what are the costs of climate inaction?!‣for local and global economic output ‣for poverty and inequality
Impact of climate change
Main question: what are the costs of climate inaction?!‣for local and global economic output ‣for poverty and inequality
What we need to know: 1. how much will the climate change (“business as usual”) 2. how will humans (+systems on which they depend) respond
Impact of climate change
Main question: what are the costs of climate inaction?!‣for local and global economic output ‣for poverty and inequality
What we need to know: 1. how much will the climate change (“business as usual”) 2. how will humans (+systems on which they depend) respond
Climate science tells us #1.
Impact of climate change
Main question: what are the costs of climate inaction?!‣for local and global economic output ‣for poverty and inequality
What we need to know: 1. how much will the climate change (“business as usual”) 2. how will humans (+systems on which they depend) respond
Climate science tells us #1.History gives us a clue about #2.
The news from climate science…
IPCC AR5 2013
The news from recent historyHow do people respond to changes in climate?
The news from recent history
PRODUCTIVITY OF CROPS
How do people respond to changes in climate?
Plants don’t like it hot
US maize yields
Schlenker and Roberts 2009
Plants don’t like it hot
US maize yields
Schlenker and Roberts 2009
African maize yields
Lobell et al 2011
Plants don’t like it hot
US maize yields
Schlenker and Roberts 2009
Rule of thumb: -1% yield for every day spent above 30C
African maize yields
Lobell et al 2011
The news from recent history II
PRODUCTIVITY OF PEOPLE!PRODUCTIVITY OF CROPS
People don’t like it hot
Graff Zivin and Neidell 2014
Temperature and hours worked (US)
People don’t like it hot
Graff Zivin and Neidell 2014
Temperature and hours worked (US)
% p
rodu
ctio
n lo
ss
-4
-3
-2
-1
0
US India
Temperature and production
manufacturing (days > 32C)
manufacturing (days > 25C)
Cachon and Olivares 2012; Adhvaryu et al 2014
News from recent history III
PEACEFULNESS OF PEOPLE!PRODUCTIVITY OF PEOPLE!PRODUCTIVITY OF CROPS
Hot under the collar?
BENVOLIO (TO MERCUTIO)
I pray thee, good Mercutio, let’s retire.The day is hot, the Capulets abroad,And if we meet we shall not ’scape a brawlFor now these hot days is the mad blood stirring. !
— Shakespeare, Romeo and Juliet (then Tybalt kills Mercutio, Romeo kills Tybalt, etc..)
Hsiang Burke Miguel 2013
Hsiang Burke Miguel 2013
Re-analyzing ~25 studies, we find for 1 sd increase in temperature: • 10% increase in group conflict (e.g. civil war) • 2% increase in individual conflict (e.g. murder)
History speaks. “micro” evidence tells us that: !when it’s really hot: less food, less production, less peace
But at a global scale? !!
Past: Does “macro” reflect “micro”? Future: growth & inequality as climate changes?
History speaks. “micro” evidence tells us that: !when it’s really hot: less food, less production, less peace
Assemble: 50 years of growth data for >150 countries !Ask: How do changes in temperature affect aggregate economic performance, past and future?
0 5 10 15 20 25 30
��
��
���
���
annu
al g
row
th in
GD
P/ca
p
annual avg. temperature ( C)
global distribution of temperature observations
global distribution of populationat each temperature
global distribution of GDPat each temperature
US
China
GermanyJapan India
Nigeria
IndonesiaBrazil
FranceUK
Burke Hsiang Miguel 2015
Burke Hsiang Miguel 2015
−1 0 1ppt effect on growth rate
Effect of a +1C temperature increase on growth
Now run the world forward:
2020 2060 2100Index
1
−80
−40
0
40
80Germany
2020 2060 2100Index
1
−80
−40
0
40
80US
2020 2060 2100
1
−80
−40
0
40
80China
2020 2060 2100
1
−80
−40
0
40
80Nigeria
2020 2040 2060 2080 2100
−60
−40
−20
0
20
40
60
chan
ge in
glo
bal G
DP/
cap
(%)
Global
2100, with “business as usual” emissions (RCP8.5):
% c
hang
e in
GD
P/ca
pita
Now run the world forward:
2020 2060 2100Index
1
−80
−40
0
40
80Germany
2020 2060 2100Index
1
−80
−40
0
40
80US
2020 2060 2100
1
−80
−40
0
40
80China
2020 2060 2100
1
−80
−40
0
40
80Nigeria
2020 2040 2060 2080 2100
−60
−40
−20
0
20
40
60
chan
ge in
glo
bal G
DP/
cap
(%)
Global
2100, with “business as usual” emissions (RCP8.5):
% c
hang
e in
GD
P/ca
pita
The rich stay the same, poor get poorer
2020 2040 2060 2080 2100
�
�
�
�
0
year
aver
age
chan
ge in
GD
P/ca
p (%
)Average effects by 2010 income quintile
richest 20% in 2010
poorest 20% in 2010
20th-40th pctile
60th-80th pctile
40th-60th pctile
What do we learn?
If we do nothing about climate change:!
‣ Likely that we will be substantially poorer on average
‣ Very likely that any negative impacts will disproportionately fall on poorest countries ‣ poor countries are already quite hot
What do we learn?
If we do nothing about climate change:!
‣ Likely that we will be substantially poorer on average
‣ Very likely that any negative impacts will disproportionately fall on poorest countries ‣ poor countries are already quite hot
Damages are potentially so large that emissions reductions are likely to be win-win:!
! global inequality reducing, sustainability promoting!
