The dual challenge: doubling yields in the face of water

scarcity and climate change

Dr David MoldenIWMI

Water for a food-secure worldWater for a food-secure world

About IWMIIWMI is one of 15 research centers supported by the Consultative Group on International Agricultural Research (CGIAR).

Mission: To improve the management of land and water resources for food, livelihoods and the environment.

Where we work:Headquarters: Colombo, Sri LankaIn Africa : Ghana, Southern Africa, EthiopiaIn Asia: India, Pakistan, Nepal, Laos, Vietnam, Central Asia, Syria

Water Scarcity 2000

1/3 of the world’s population live in basins that have to deal with water scarcity

More People – 6.5 to 9 billion people by 2050

More calories & more meat, fish, milk

More food production – need to double grain production by 2050

More water for food – if practices don’t change, double water needs

This equation doesn’t work – something has to change

Will there be enough water?More people – 6.5 to 9 billion people by 2050

More calories & more meat, fish, milkMore food production – need to double grain production by 2050

More water for food – if practices don’t change, water needs for agriculture will double

Something has to change

Climate Change

Mitigation is about gases.Adaptation is about water.

Some areas will be wetter, others drier

Source: Arnell, 2003 – IWMI, FAO, ADB report on revitalizing irrigation.

Water Scarcity and Climate Change

Some areas wetter, some areas drier

Water for a food-secure world

Hydrological Modeling (SWAT)

Rainfall-Runoff simulation to determine impacts of CC on flow regimes and groundwater recharge

Rainfall Evapotranspiration

Runoff

Results – one scenario (A1B), one sub-catchment in the Volta

Variability in Precipitation

Thornton et al 2006

likely to increase with climate change

- Costs 1/3rd of growth potential- Occurs as prolonged dry spells, drought and floods

Impact of rainfall variability on GDP and Agricultural GDP growth

-80

-60

-40

-20

0

20

40

60

80

19

82

19

83

19

84

19

85

19

86

19

87

19

88

19

89

19

90

19

91

19

92

19

93

19

94

19

95

19

96

19

97

19

98

19

99

20

00

year

%

-30

-25

-20

-15

-10

-5

0

5

10

15

20

25

rainfall variability

GDP growth

Ag GDP growth

Unmitigated rainfall and hydrological variability

Source: World Bank, 2006. A Country Water Resources Assistance Strategy

for Ethiopia

Growth in Yields

United States

China

Latin America

Sub-Saharan Africa

IPCC – yields in SSA will decline by 50% because of climate change

It is possible to more than double yields in SSA in spite of climate change.

SolutionsOlivia Molden

Water Management

Around 70% of the world’s under-nourished live in rural areas where non-agricultural livelihood options are limited.

Get water to poor people, use it better

Improve and Safeguard Water Access

Access to Technologies

But need to re-think water storage: role of groundwater and soil moisture.

And beyond: insurance, local trade, …

Cub

ic m

eter

s pe

r ca

pita

Water Storage Mitigates Climate Variability

4 43 7

46 128

7

140

6 248

6

325

5 472

9 615

0

01,0002,0003,0004,0005,0006,0007,000

Ke

nya

Eth

iopi

aS

out

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fric

aT

hai

lan

d

Lao

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Ch

ina Bra

zil

Au

stra

liaN

ort

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me

rica

Source: World Bank data from

ICOLD

Water for a food-secure world

Physical Water Storage Continuum

Growing Enough Food

With Water Scarcity andClimate Change

David Molden

Irrigation potential

developed:

Egypt, Morocco,

Somalia, South Africa > 75%

Botswana, Sudan,

Zimbabwe, Madagascar, Mali, Malawi,

Uganda 50-75%

Rest < 50%

% Irrigated Land

INDIA: ~50

SSA: 5

Upgrade Water Management in Rainfed Landscapes

Even if large scale irrigated area doubles, the contribution to food production for SSA from irrigation would change from 5 to 11%.

Rainfed land has the highest potential for poverty reduction and water productivity gains.

Consider A Range of Agricultural Water Management Options

Fish, Livestock, Crops, Ecosystem Services

A range of options Water sources in Krishna basin

Krishna river basin

24 major reservoirs

6100 small reservoirs

High groundwater use

Water for a food-secure worldMap source: Survey Dept.

For Water Security

Storage is the best “No regret” option!

Water for a food-secure worldWater for a food-secure world

Doubling Yields water + more

• Access to technology, seeds, fertilizers?• Is there enough money

or credit to buy them?• Are markets available to sell?• Financially viable?• Water and land resources available?• Is it sustainable – financial, ecological?• Supportive policies?• “Mind mobilization” Matsepo Khumbane

FAO - SSA 245 Million 58% are rural poor

AWM Team - SSA 279 Million 65% are poor

AWM Team - India

220 Million 90% are poor

Who could benefit from Agricultural Water Management Solutions?

From Scoping Study for Agricultural Water Management Solutions Project

If this is so good, why doesn’t it happen?

It is happening….

Small Reservoirs

Multiple-use systems integrating domestic water, irrigation, fisheries, livestock,

industries – provide income, nutrition and health benefits, and improve water productivity

healthlabour saving,gender

resilient food and income….

..from livestock..from fish

..from enterprise

..from crops

Groundwater – offers opportunities for the rural poor.

Needs:1) Better information on availability1) Access to technologies2) promote sustainable use

IDE rope pump, Ethiopia

A groundwater revolution in SSA: Benefits with little cost?

Groundwater is under-utilized in Sub-Saharan Africa

Groundwater is under-utilized in Sub-Saharan AfricaCu

ltiva

ted

area

as

% o

f cel

l are

a

In Asia groundwater is often the only water available

In Asia groundwater is often the only water available

Water for a food-secure world

It is happening….

But not fast enough!

Why doesn’t it happen faster?

• Missed opportunities:– AWM falls between institutional cracks– Failure to focus on women

• Water focus is on drinking water, hydropower, large irrigation

• Its not just about technologies, but about markets, institutions, capacity

What will it take?• Continuous learning from a range of

knowledge and experience• A new and significantly increased capacity • Crafting solutions, paying attention to

context• Adapting technologies and institutions• Engaging public, policy makers & investors • You…..

Water for a food-secure world

Thank You !

“Anyone who can solve the problems of water will be worthy of two Nobel Prizes – one for peace and one for science”

John F Kennedy