The Impact of Climate Change on Human Welfare in a Warmer World

Indur M. Goklany*Asst. Director, Programs & Science & Technology Policy

Office of Policy Analysis, US Department of the Interior

*Views expressed here are mine, and not the Department

of the Interior or the US Government’s

Examining Impacts:Beyond the Usual Scientific Debate

Scientific debate focuses on whether climate has warmed, by how much, how rapidly, due to what, and what fraction may be due to manmade GHGs.

For the sake of argument, assume the validity of IPCC view that climate change is “very likely” due to anthropogenic greenhouses gases.

Evaluate various claims about the CC.

Use estimates of the global impacts of climate change based on the IPCC emission and climate change scenarios.

Claims about climate change impacts

1.Human and environmental well-being will be lower in a warmer world even if we are wealthier

2.Our descendants will be worse off than us, if we don’t reduce climate change now

3.Global warming is the world’s most important environmental problem

Sources of Information

Global impacts of climate change • FTAs = Fast Track Assessments: sponsored by the British

government (peer-reviewed; published 1999 and 2004). Authors intimately involved in writing IPCC reports.

• Stern Review: 2006 study on the economics of climate change commissioned by the British government from Nicholas Stern, a former chief economist of the World Bank.

Mortality estimates

• World Health Organization (WHO)

Costs estimates

• Intergovernmental Panel on Climate Change (IPCC)

• United Nations Millennium Project

Welfare losses due to climate change2050–2200

Source: Stern Review (2006)

Most Important Food, Environmental and Nutritional Problems, Based on Mortality for 2000

Risk factor Ranking Mortality (millions)

Mortality (%)

Blood pressure 1 7.1 12.8

Cholesterol 2 4.4 7.9

Underweight (hunger)

3 3.7 6.7

Low fruit & vegetables

4 2.7 4.9

Overweight 5 2.6 4.6

Unsafe water, poor sanitation

6 1.7 3.1

Indoor smoke 7 1.6 2.9

Malaria 1.1 2.0

Source: WHO 2002

Most Important Food, Environment, and Nutritional Problems for 2000, Based on Mortality

(continued)

Risk factor Ranking Mortality (millions)

Mortality (%)

Iron deficiency 8 0.8 1.5

Urban air pollution 9 0.8 1.4

Zinc deficiency 10 0.8 1.4

Vitamin A deficiency 11 0.8 1.4

Lead exposure 12 0.2 0.4

Climate change 13 0.2 0.3

Subtotal 27.6 49.4

TOTAL from all causes 55.8 100.0Source: WHO 2002

4,368

2,067

6,012

3,075

2,010

237

282

116

92

-500

500

1,500

2,500

3,500

4,500

5,500

6,500

7,500

Baseline 1990

A1FI (4 °C)

A2 (3.3 °C)

B2 (2.4 °C)

B1 (2.1°C)

Dea

ths

(000

's)

Deaths in 2085 from Hunger, Malaria, & Coastal Flooding

No CC

Because of CC

Total 2,304

Total 6,295

Total 3,191

Total2,102

Sources: Goklany (2008), based on Parry et al. (2004), Nicholls (2004), WHO (2002), Martens (1999).

0

-1,192-1,050

-417-634

1,368 1,667

7,016

4,114

2,225

-4,000

-2,000

0

2,000

4,000

6,000

8,000

10,000

Baseline 1990

A1FI (4 °C)

A2 (3.3 °C)

B2 (2.4 °C)

B1 (2.1°C)

PA

R (m

illi

on

s)

Water Stress: Population at risk (PAR) in 2085 Because of CC, and Total

Additional PAR With CC

Total PAR

Source: Arnell et al. (2004).

11.6%

5.0%

13.7%

7.8%

0%

2%

4%

6%

8%

10%

12%

14%

16%

Baseline 1990

A1FI (4.0 °C)

B2 (2.4°C)

B1 (2.1 °C)

habi

tat c

onve

rted

to c

ropl

and

(as

% o

f glo

bal l

and

area

)

Global Conversion of Habitat to Croplandwith Climate Change (in 2100)

Sources: Levy et al. (2004).

13%9% 9% 10%

47% 47%

22% 22%

53% 52%

28% 28%

0%

10%

20%

30%

40%

50%

60%

A1FI (4.0 °C)

A2 (3.3°C)

B2 (2.4°C)

B1 (2.1 °C)

loss

of w

etla

nd

are

a(a

s %

of

1990

are

a)Average global loss of coastal wetlands

(1990-2085)

Losses due to SLR alone

Losses due to other causes

Combined losses

Sources: Nicholls (2004).

Over the Foreseeable Future

1.Will climate change lower the welfare of future generations to below today’s? NO

2.Will well-being necessarily be lower in a richer-but-warmer world? NO

3. Is global warming the world’s most important environmental problem? NO

4.How best to reduce damages from global warming while dealing with more urgent problems?

4,368

2,067

6,012

3,075

2,010

237

282

116

92

-500

500

1,500

2,500

3,500

4,500

5,500

6,500

7,500

Baseline 1990

A1FI (4 °C)

A2 (3.3 °C)

B2 (2.4 °C)

B1 (2.1°C)

Dea

ths

(000

's)

Deaths in 2085 from Hunger, Malaria, & Coastal Flooding

No CC

Because of CC

Total 2,304

Total 6,295

Total 3,191

Total2,102

Sources: Goklany (2008), based on Parry et al. (2004), Nicholls (2004), WHO (2002), Martens (1999).

Focused Adaptation

Focus on reducing each urgent hazard.

• Build resilience and reduce vulnerability to today’s urgent climate-sensitive problems — malaria, hunger, water scarcity, coastal flooding, threats to biodiversity — that might be exacerbated by future climate change.

Focused Adaptation — Examples• Reduce Malaria by 75%; Cost = $3 billion/yr

malaria vaccine, indoor residual spraying with DDT, insecticide treated bed nets.

• Reduce Hunger by 50%; Cost = $12-15 billion/yr

develop crops for poor climatic or soil conditions (namely, drought, water-logging, high salinity or acidity)

develop crops for higher CO2 and temperature conditions

• Reduce Vulnerability to Extreme Events; Cost = $2-10 billion/yr

insurance reform; early warning systems; coastal defenses

• Reduce Water Stress

develop drought-resistant crops; property rights for water; water pricing

A Broader Approach to AdaptationSustainable Development

• Broadly enhance adaptive capacity by increasing economic development, human capital and propensity for technological change.

• Requires strengthening and/or developing the institutions that underpin adaptive capacity.

• This is also the essence of sustainable development.

• One specific approach might be through adherence to the UN Millennium Development Goals (MDGs).

Increasing society’s adaptive capacity

• Increases society’s resilience to all manner of adversity, and not just climate change.

• Broadly advances human well-being, and sustainable (economic) development.

• Enhances capacity to mitigate emissions.

• Could raise level at which greenhouse gas concentrations might become “dangerous” and/or allow mitigation to be postponed. Either would reduce mitigation costs.

Maximum benefits in 2085 & costs of mitigation & adaptation, under warmest scenario (A1FI)

Mitigation Adaptation

Kyoto No CC after 1990

Focused adaptation

Broad development

Lives saved from malaria, hunger & coastal flooding (in 000s)

21

(1%)

237

(10%)

1,480

(64%)

1,480

(64%)

Decline in net PAR for water stress (in millions)

-83

(-5%)

-1,192

(-72%)

up to 1,667

(+)

Up to 1,667

(+)

Progress toward other MDGs• poverty reduced 50%• child mortality rate reduced 67%• maternal mortality rate reduced 75%• access rates for safe water & sanitation increased 50%• illiteracy rate reduced 100%

Almost none

Some Substantial MDGs should be met

Habitat for other species (relative to 1990 level)

Small decline

Larger decline

Habitat doubled by CC

Habitat doubled by CC

Cost in 2010-2015 ($ billions)/year 165 >>165 ~34 ~165

Sources: IPCC (2001), Parry et al. (2004), Arnell (2004), Nicholls (2004), Arnell et al. (2002), UNMP (2005).

SummaryThrough the foreseeable future (2085-2100):

• climate change is probably not the world’s most important public health or environmental problem.

• Richer-but-warmer worlds will likely have higher well-being than cooler worlds.

• Future generations will have greater capacity to both adapt to AND mitigate climate change because they’ll be wealthier, have more human capital and better technology.

• Adaptation is superior to mitigation. Adaptation would:

– Reduce climate- AND non-climate related risks faster, more effectively, with greater certainty, and at lesser cost.

– Advance well-being and sustainable development more effectively.

.

Interim PoliciesAdaptation• Increase society’s resilience to adversity in general

– advance economic growth, human capital and propensity for technological change

– Would enhance both adaptive and mitigative capacity

• Undertake focused adaptation– reduce vulnerability to today’s urgent climate-sensitive problems that

might be exacerbated by future climate change

Mitigation• Let market select “no-regret” actions• Expand range of “no-regret” actions (through R&D)

Science & Monitoring• More robust knowledge of science, impacts and policies• Continue monitoring to spot “dangerous” impacts before they

become imminent [Adaptive Management]

Solve the urgent problems facing today’s generations while advancing

the ability of tomorrow’s wealthier population to address whatever

challenges they’ll confront

Indur Goklany, “What to Do about Climate Change,” Policy Analysis No. 609, Cato Institute, February 5, 2008.

Available at:

http://www.cato.org/pubs/pas/pa-609.pdf

The End

Current Impacts Assessment

Climate ChangeUsing AOGCMs

Human Impacts

IPCC Emissions Scenarios

Radiative Forcing

Atmospheric Concentrations

Effects on biophysical systems

Socioeconomic Assumptions

Interconnections

Fig. 6-17: Global deaths & death rates due to climate related disasters, 1900-2004

128

25

485446

180211

167

74 6632 19

79

14

242209

76 7149

19 14 6 30

200

400

600Deaths (in 1000s)

Death rates (per million)

Source: Based on data from EM-DAT (2005), McEvedy & Jones (1978), WRI (2005).

Cereal Yield vs. Income, 1975-2003

0

2000

4000

6000

8000

10000

0 10,000 20,000 30,000 40,000

GDP per capita (2000 International $, PPP)

cere

al y

ield

(k

g p

er h

ecta

re)

cy1975 cy2003 cyp1975 cyp2003

Source: Based on data from World Bank (2005b).

Food Supplies per capita vs. Income, 1975-2002

1500

2000

2500

3000

3500

4000

0 5,000 10,000 15,000 20,000 25,000 30,000 35,000 40,000 45,000 50,000

GDP per capita (2000 Interntional $, PPP)

kca

ls/c

apit

a/d

ay

fs1975 fsp1975 fs2002 fsp2002

Source: Based on data from World Resources Institute (2005), World Bank (2005b).

Malnutrition Prevalence vs. Income, 1987-2000

0

30

60

90

0 3,000 6,000 9,000 12,000 15,000 18,000 21,000 24,000

GDP per capita (2000 International$, PPP-adjusted)

% o

f ch

ildre

n u

nd

er 5

yrs

mwp1987 mwp2000 mw1987 mw2000

Source: Based on data from World Bank (2005).

Infant Mortality vs. Income, 1980-2003

0

50

100

150

200

250

0 5,000 10,000 15,000 20,000 25,000 30,000

GDP per capita (2000 International $, PPP)

dea

ths

per

100

0 liv

e b

irth

s

im1980 im2003 imp1980 imp2003

Source: Based on data from World Bank (2005b).

Life Expectancy vs. Income, 1977-2003

30

40

50

60

70

80

90

0 10,000 20,000 30,000 40,000 50,000

GDP per capita (2000 International $, PPP)

Lif

e ex

pec

tan

cy (

yrs.

)

le1977 lep1977 le2003 lep2003

Source: Based on data from World Bank (2005b).

Figure 10-1: Human well-being vs. wealth, early 2000s

0

25

50

75

100

125

150

$0 $8,000 $16,000 $24,000 $32,000 $40,000

per capita income (in 2000 International dollars)

Life

Exp

, Inf

Mor

t, Te

rt

Sch,

Saf

e H2O

, Ch

Lab

0

500

1000

1500

2000

2500

3000

3500

Dai

ly F

ood

Supp

ly

(kca

l)/ca

pita

Life Expectancy, 2003 Inf Mortality, 2003 Tertiary School, 2002

Access to Safe H2O, 2002 Child Labor, 2003 Food Supply, 2002

Source: World Resources Institute (2005); World Bank (2005).

Figure 10-2: Total fertility rate vs. wealth, 1977-2003

0

2

4

6

8

0 10,000 20,000 30,000 40,000 50,000 60,000

GDP per capita (2000 International $, PPP-adjusted)

child

ren

per w

oman

tfr1977

tfr2003

tfr1977p

tfr2003p

Source: Based on data from World Bank (2005).

Population at Risk (PAR) in 2085 from Malariawith and without Climate Change

Sources: Martens (1999); Arnell et al. (2002)

028

-18.5 -3

10

835

133

748.5

230

100

-100

0

100

200

300

400

500

600

700

800

900

1,000

Baseline 1990

A1FI (4 °C)

A2 (3.3 °C)

B2 (2.4 °C)

B1 (2.1°C)

Po

pu

lati

on

at

risk

(m

illio

ns)

Global Population at Risk for Hunger, 2085with and without CC

Additional PAR With CC

Total PAR

Source: Parry et al. (2004)

Focused AdaptationReducing Hunger

Focus additional resources on:

• R&D into solving the developing world’s current agricultural problems that might worsen with climate change, e.g., growing crops in poor climatic or soil conditions (such as drought, or water-logged, highly saline or acidic soils).

• Developing cultivars for conditions likely to be strengthened in the future independent of the accuracy of climate models, e.g., higher CO2 and temperature conditions.

• Higher yield, low impact cultivars and agronomic practices.

• Reducing losses and wastage at each stage of agricultural and food production – from pre-harvest to post-harvest to end-use.

Reducing Total PAR through 2085Water Shortage

• Climate change is more likely to increase the global PAR.

• Mitigation, therefore, may make matters worse in many areas.

• Practices that would help cope with current shortages would also help address any future climate-change-caused shortages. These practices include:

– Institutions treating water as an economic commodity, i.e., transferable property rights to water, water pricing

– Development of drought resistant crops, and greater use of precision agriculture

Focused AdaptationCo-benefits of Institutional Changes to Make

Water Use More Efficient

• More efficient water use, particularly in the agricultural sector, will reduce human demand for freshwater -- the greatest current threat to freshwater biodiversity.

• Increase the likelihood of meeting human demand for food. Water availability is sometimes cited as the greatest threat to future food security.

• Reduce a significant barrier to sustainable development.

GDP per capita in 2100 per IPCC scenariosassuming no CC

14,500

107,300

46,200

54,400

72,800

875

66,500

11,000

18,000

40,200

$0

$20,000

$40,000

$60,000

$80,000

$100,000

$120,000

Baseline 1990

A1FI (4 °C)

A2 (3.3 °C)

B2 (2.4 °C)

B1 (2.1°C)

19

90

U.S

. D

olla

rs, M

XR

Industrialized Countries

Developing Countries

Sources: Arnell et al. (2004), World Bank (2006); IPCC (2000)

875

66,500

11,000

18,000

40,200

14,500

43,092

8,365

15,719

36,300

$0

$10,000

$20,000

$30,000

$40,000

$50,000

$60,000

$70,000

Baseline 1990

A1FI (4 °C)

A2 (3.3 °C)

B2 (2.4 °C)

B1 (2.1°C)

1990

U.S

. Do

llar

s, M

XR

Net welfare per capita, 2100developing countries

adjusted for losses from climate change

GDP/Capita, No CC, DevelopingGDP/Capita, No CC, IndustrializedNet Welfare/Capita, Developing

Sources: Goklany (2007c), based on Stern (2006), Arnell et al. (2004), World Bank (2006), IPCC (2000).

Maximum benefits in 2085 & costs of mitigation & adaptation, under warmest scenario (A1FI)

Mitigation Adaptation

Kyoto No CC after 1990

Focused adaptation

Lives saved from malaria, hunger & coastal flooding (in 000s)

21

(1%)

237

(10%)

1,480

(64%)

Decline in net Population at Risk for water stress (in millions)

-83

(-5%)

-1,192

(-72%)

up to 1,667

(+)

Progress toward other MDGs• poverty reduced 50%• child mortality rate reduced 67%• maternal mortality rate reduced 75%• access rates for safe water & sanitation increased 50%• illiteracy rate reduced 100%

Almost none

Some Substantial

Habitat for other species (relative to 1990 level)

Small decline

Larger decline

Habitat doubled

Cost in 2010-2015 ($ billions)/year 165 >>165 ~34

Sources: IPCC (2001), Parry et al. (2004), Arnell (2004), Nicholls (2004), Arnell et al. (2002), UNMP (2005).

Net Biome Productivitywith climate change

0.7

5.8 5.9

3.1

2.4

0

1

2

3

4

5

6

7

Baseline 1990

A1FI (4.0 °C)

A2 (3.3 °C)

B2 (2.4°C)

B1 (2.1 °C)

Ne

t Bio

me

Pro

du

cti

vit

y(P

g C

/yr)

Sources: Levy et al. (2004).