Climate Change Impacts on Water, Agriculture and Food

Security

Dr. EJ Mwendera

Institute for Soil, Water and Climate of the Agricultural Research Council (ARC-ISCW), Pretoria, South Africa

CN+ Expert Workshop on Climate Change, Food Security & Water Resources

AU Commission, Addis Ababa, Ethiopia 25–26 June 2013

Presentation outline

• Relationships between water, agriculture and food security

• Climate change affecting water, agriculture and food security

• Predicted effect of climate change on agriculture and food security

• Some water and climate change research

• Main issues for bio-regional research and technology development

Relationships between water, agriculture and food security

Food security

Food Availability Production; Distribution; Exchange

Food utilization Nutritional value; Social

value; Food safety

Food Access Affordability; Allocation;

Preference

Food availability Food access

Food utilization

(Modified from: FAO, 2002)

Water and agriculture • Agriculture is by far the biggest user of water, accounting for

almost 70% of all withdrawals, and up to 95% in developing countries.

• The water needed for crops amounts to 1 000-3 000 cubic meter per tonne of cereal harvested. Put another way, it takes 1 - 3 tonnes of water to grown 1kg of cereal.

• The daily drinking-water requirements per person are 2-4 litres.

• However, it takes 2 000 - 5 000 litres of water to produce a person’s daily food.

(Source: FAO)

Access to water and food security

A composite indicator that incorporates measures of water resources (from rainfall, river flows and aquifer recharge), access, environmental issues (water quality) and pressure on resources

(Source: FAO, CEH Wallingford)

Causes of food emergencies in developing countries

(Source: FAO)

Climate change affecting water, agriculture and food security

Climate change links

Increased water demand Reduced water availability

Reduced food security Reduced agricultural production

(Photo: Howard Burditt/Courtesy Reuters) (Photo : World Food Programme)

(Photo : Scienceworldreport.com)

Growth in yields

Source: US data, USDA’s National Agricultural Statistics Service; all other regions, FAOSTAT.

Rainfall variability vs GDP in Ethiopia

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

Key findings in Ethiopia

• Extreme hydrological variability is echoed in its economic performance; • Vast majority (80%) of Ethiopia’s population subsists on rainfed agriculture; • People’s welfare and economic productivity are linked to the volatile rains; and • There is a strong correlation between rainfall and overall GDP.

Rainfall variability vs GDP in Zimbabwe

SOURCES: Craig J. Richardson, 2005; Meteorological Services Department, Zimbabwe, and World Bank (2002) World Development Indicators

Role of agriculture in climate change problem

Contribution of agriculture to climate change is often overlooked;

IPPC estimated that 31% of total emission of GHGs in 2004 came from agriculture and forestry;

Hence, mitigation efforts must also address contribution of agriculture to the climate change problem

Predicted effect of climate change on agriculture and food security

-1.9

-5 -4.3

3.7

-3.9

-1

-8.6

15.9

-10

-5

0

5

10

15

20

Developing world Sub-Saharan Africa Asia Latin America

Per

chen

t ch

ange

in a

gric

ult

ura

l GD

P a

nd

cer

eal p

rod

uct

ion

Percent change in agricultural GDP

Percent change in cereal production

Projected CC impact on agricultural GDP and cereal production in 2080

Source: International Institute for Applied System Analysis

Predicted change in net revenue as a result of decreased rainfall and increased temperatures

Turpie and Visser (2012) using three Atmospheric Oceanic General Circulation Models (AOGCM) of Canadian Climate Center (CCC), Centre for Climate System Research (CCSR), and Parallel Climate Model (PCM) models.

Some water and climate change research

Water and climate change research at ARC-ISCW

Institute for Soil, Climate and Water (ISCW)

Agricultural Research Council (ARC)

(Source: ARC-ISCW, Arcadia, Pretoria, RSA)

ARC-ISCW Agroclimatology Programme

Main research activities:

Climate monitoring;

Climate and crop modelling;

Weather dissemination (radio, TV);

GHG emission monitoring;

Adaptation and mitigation

Weather station network • 60 Mechanical • 500 Automatic

(Source: Agroclimatology Programme ARC-ISCW, Arcadia, Pretoria, RSA)

ARC-ISCW Geoinformatics Programme

(Source: GeoInformatics Programme, ARC-ISCW, Arcadia, Pretoria, RSA)

Soil information for land evaluation, ranging from commercial farmers to small-scale farmers

ARC-ISCW Soil Science Programme

(Source: Pedometrics Programme ARC-ISCW, Arcadia, Pretoria, RSA)

Water quality management in agro-ecological systems;

Efficient utilisation of water in rain-fed and irrigated agricultural systems, forestry and livestock production systems;

Sustainable management of water resources in wetlands to enhance ecosystem health and functioning.

Assessment of climate change impacts on water and agro-ecological systems

ARC-ISCW Water Science Programme

(Source: Water Science Programme ARC-ISCW, Arcadia, Pretoria, RSA)

ARC-ISCW Analytical Services Laboratory

- Soil analysis;

- Water analysis

- Spatial inorganic/biological analysis

(Source: Christa Lombard, Projects Office, ARC-ISCW, Arcadia, Pretoria, RSA)

LOCATION OF CASE STUDY AREAS

Cons agriculture, Qunu, E Cape

Cons agriculture, Pretoria, Gauteng

Rain water harvesting, Thaba Nchu, Free State

(Source: Beukes, DJ Botha, JJ, Steinke, MF & Wood, PC, 2011)

200

220

240

260

280

300

320

340

360

380

400

0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150Day of year

So

il w

ate

r co

nte

nt

(mm

)

ConIRWHDULLLRain-200

IRWH>Con: 43%

IRWH>Con: 38%

320

340

360

380

400

420

440

460

480

0 10 20 30 40 50 60 70 80 90 100 110 120 130

Days after planting

So

il w

ate

r co

nte

nt

(mm

)

ConIRWHDULLLRain-320

Soil water under rainwater harvesting

(Source: Beukes, DJ Botha, JJ, Steinke, MF & Wood, PC, ARC-ISCW, 2011)

Enhances rainwater productivity

Assessment of maize and sunflower over:

48 Growing seasons

Six different locations

Mean seasonal rainfall: 320 mm

RWP (kg grain ha-1 mm-1 water):

Conventional tillage: 2.7

IRWH practice: 4.1 (+52%)

(Source: Beukes, DJ Botha, JJ, Steinke, MF & Wood, PC, 2011)

Crop yields under rainwater harvesting

Crop Yield under

conventional

tillage (kg/ha)

Yield under infield

IRWH system

(kg/ha)

Yield increase in

IRWH system

(%)

Maize 1,070 3,753 250

Dry beans 262 407 55

Sunflower 1,037 1,698 64

(Source: Botha et al., 2012, ARC-ISCW, Glen, Bloemfontein, RSA)

Linking roof water harvesting to irrigation

• Can improve household food security in rural areas

(Source: Botha et al., 2012, ARC-ISCW, Glen, Bloemfontein, RSA)

Climate change coping and adaptation strategies

Providing water for livestock

Restoring degraded areas

Scarce water for livestock

Degraded areas (Source: Mwendera et al., 2010, IUCN, Nairobi, Kenya)

Climate change coping and adaptation strategies (cont’d)

Installing efficient water infrastructure

Exploiting groundwater resources

Degraded water infrastructure

Limited surface resources

(Source: Mwendera et al., 2010, IUCN, Nairobi, Kenya)

What is needed:

1) Better information on availability

1) Access to technologies

2) Promote sustainable use

Groundwater – offers opportunities for the rural communities.

Harnessing groundwater

(Source: Karen G. Villholth, IWMI-SA, 2012

Information Days

(Source: Corrie Swanepoel & Danie Beukes, 2012)

Establishing water use associations and catchment forums

Climate change coping and adaptation strategies (cont’d)

(Source: Mwendera EJ, 2010, IUCN, Nairobi, Kenya)

Main issues for bio-regional research and technology

development

Understanding the problem

There is currently much uncertainty in the climate change projections.

Predicting how these uncertain changes will affect agricultural and food systems is still difficult.

Most of the vulnerability and sensitivity mapping studies have been at regional scales, masking enormous variation at the local level.

Challenge of downscaling of vulnerability assessment and mapping exercises.

The policy challenge

1. Producing the evidence to guide policy;

2. Engaging with the policy world to ensure

that policy responds to the evidence;

3. Understanding the real impacts of such

policies and policy change; and

4. For policy makers to provide a fast enough

response to meet the urgency of the

situation.

Engagement and communication

The process by which knowledge informs action.

Agriculture is intensely local, and requires that information be relevant and useful at that level.

Close gaps between knowledge and action, in the wake of a plethora of new tools for information exchange.

Strategic partnerships and learning platforms,;

Providing knowledge and support to the institutional changes needed for uptake and scaling out of technologies.

Key questions in AWM interventions

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 (including rights)?

Is it sustainable – socially, financially, ecologically?

Are there supportive institutions?

Do we have supportive policies?

Example of an approach to revitalize small-scale irrigation schemes

Irrigation system analysis Water availability analysis Socio-economic analysis

Market linkages study Monitoring & evaluation Entrepreneurial training

(Source: Mwendera, E.J. and P. Chilonda (2013). Conceptual framework for revitalisation of small-scale irrigation schemes in southern Africa. Journal of Irrigation and Drainage 62(2): 2008–220)

ARC Climate Change Focus Areas & NR Requirements

Map production areas (present & future)

Adaptation/

Mitigation

Pests/

diseases/

vectors

Climate/water

data;

probabilities

Soil/terrain/

suitability data

NR integrated/

land cover/

monitoring

ARC CC Program Focus Priorities &

examples of initial R&D

Mapping production areas

• Crop suitability

• Commodities: maize, wheat, soya beans, potatoes as 1st phase

Pests, vectors, parasites & diseases (plant and animal health)

• Rift Valley Fever, African Horse Sickness

• Plant diseases e.g. common rust, gray leaf spot and emerging diseases

Mitigation and adaptation

• Conservation agriculture (soil-water-nutrient-biodiversity conservation)

• Climate-smart interventions

ARC CC Program Objectives

1. Identify, characterize & map existing & potential production areas

for food, feed & fibre crops & livestock under current climatic

patterns and to-be-agreed scenarios of climate change

2. Investigate possible effect of CC on vector, parasite, pest and weed

distribution/dynamics and on epidemiology of plant/animal diseases

3. Develop & implement strategies for mitigation of and adapting to

CC through breeding & production practices

4. Promote inter-institutional cooperation in addressing larger CC

challenges across disciplinary boundaries through effective

research

5. Create an effective network with international, regional and national

organizations working on CC

Effective ARC CC Network priorities Institution Relevant R&D/ value CC Research focus

DAFF, PDAs, DRDLR Land suitability/planning; risk

assessments; drought monitoring;

climate change/climate smart-related

R&D; funding

Mitigation & adaptation

Mapping production areas

Pests, vectors, diseases

SA Weather Service Climate research partner;

supplementing climate data; climate

predictions/probabilities; modeling

Mapping production areas

Mitigation/adaptation

Pests/diseases

DEA, DWA & WRC, DST Water, wetlands, climate change &

CA-related R&D; funding

Mitigation/adaptation

Mapping production areas

Pests/diseases/vectors

Universities Partnership & training per university’s

field of specialized expertise e.g.

climate modeling

Mitigation/adaptation

Pests/diseases

Mapping production areas

CSIR & SANBI NR management R&D partners e.g.

water management, wetlands &

climate change; SANBI as

coordinator of selected DEA project

funds

Mitigation & adaptation

Mapping production areas

FAO Soil, water, conservation agriculture

partner/funder; access to UN funds

e.g. GEF

Mapping production areas

Mitigation/adaptation

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

(Source: David Molden, IWMI, 2010)