Water Security and Economic Growth: an imperative for climate change adaptation

Casey Brown, PhD, PE University of Massachusetts hydrosystems.ecs.umass.edu

Oxford Water Security Conference

18 April 2012

Introduction

• Water security is necessary for economic growth

• Achieving water security requires managing risk

• The relevant climate risk in most cases is variability

• A major risk of climate change to growth is uncertainty leading to inaction

Per Capita GDP vs Latitude

(Sachs, 2001)

Rainfall Variability and GDP

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GDP and Rainfall Variability

Mean Annual Rainfall

Monthly Rainfall Variability

Bubble Size = GDP per capita

(Blue = low interannual variability of rainfall)

Rainfall Variability and GDP

GDP and Rainfall Variability

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Mean Annual Rainfall

Monthly Rainfall Variability

Bubble Size = GDP per capita

(Blue = low interannual variability of rainfall)

Wealthy nations share a small

window of favorable climate

(low variability; moderate rainfall)

Hydroclimate risk to economic

growth

in sub-Saharan Africa

Casey Brown · Robyn Meeks ·

Kenneth Hunu · Winston Yu

Climactic Change 2011

• Hydroclimate variability is the dominant and negative climate effect on economic growth

• 10% increase in drought area causes a 40% reduction in annual growth in SSA

• Globally, 10% increase in drought area causes a 30% reduction in annual growth

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GDP per Capita ($)

GDP per cap

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Status Quo Growth Growth with 10% reduction in drought effect

Storage, Institutions and GDP

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Quality of Institutions

SSI S

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“we can spend megabucks on climate research … and still not answer the questions”

Fiering and Matalas (1990)

Assessing and Managing Climate Risk

“The past ain’t what it used to be” Yogi Berra

International Upper Great Lakes Study

Multiple Objectives:

• Ecosystem • Navigation • Recreation • Hydroelectricity Production • Coastal real estate

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NBS %Change Superior Histogram BaseCase

Climate Change Projections of Net Basin Supply - Lake Superior, 2050

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Mean NBS (% Change)

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Superior Mean Annual NBS vs Standard Deviation for 50k Year Stochastic Set for 30 year Windows

Legend

Upper C

Lower C

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Lake Superior

Mean Climate Change

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Risk Discovery: Hazards as a Function of Climate Change

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0.5Lakes Michigan-Huron Lines of Equal Zone C Expected Value Compared to Distribution of Mean NBS

Percent Change Mean NBS

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requency

Stochastic

All GCM

Climate Informed Risks – linking to Climate Information

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Expected Value of Less then or equal Historic Zone C Using Stochastic Climate

Comparison of Plan Expected Value on Lake Superior Using Stochastic versus GCM ClimateRegulation Plan Performance: Stationarity vs Climate Change

Robustness under Climate Change Projections

Ro

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• 100 Million people

• 9 basin countries

• 7 among lowest 20 HDI scores

• Investment plan of $8 billion over next 20 years

• Potential of the Basin:

• Irrigation: only 0.5 M of 2.5 M hectares

• Power: 6,000 GWh/yr of 30,000 GWh/yr

• Transport: 600 km of 3,000 km navigation transport

Shared Development Vision for the Niger Basin

Giannini et al., 2007

System Model Shows only Decreases of 10% or more cause impacts

Climate Risks and Adaptation in the Indus Basin

(Work in Progress)

Winston Yu and Ethan Yang April 9, 2012

- 3 major multi-purpose storage reservoirs, 19 barrages

- 12 inter-river link canals

- 43 major irrigation canal commands (covering over 14 million hectares)

- Over 120,000 watercourses

- Total length of the canals is about 60,000 km

Indus River Basin

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Economic Production

CC Scenarios Baseline

With Optimal Allocation With Inter-Provincial Agreement

Indus River Basin – Static Accord vs Economic Allocation

Conclusion

• In many developing countries, we know water security is not achieved and we show it impedes economic growth

• Achieving water security requires managing variability, and the challenge is greatest in the climate of the poorest countries

• Adaptation should focus on the known and current risks

• Uncertainty related to climate change need not impede to investment

• Typical global water assessments assume static/linear human response; need to account for water security (institutions, infrastructure, etc.)

Thanks! Questions: cbrown@ecs.umass.edu