Smakhtin, V., de Fraiture, C., Bossio, D., Molden, D, Hoanh C., Noble, A., Giordano, M., McCartney, M., Shah, T.

International Water Management Institute, Colombo, Sri Lanka

SECURING WATER FOR FOOD, LIVELIHOODS AND ECOSYSTEMS TO FACE CLIMATE CHANGE

Climate Change: Global Risks, Challenges and Decisions. 10-12 March 2009. Copenhagen, Denmark

WATER FOR AGRICULTURE RESEARCH IN THE CONTEXT OF CLIMATE CHANGE

Basin water impacts

Agricultural impacts

Adaptive water management

• What are the impacts of climate change on water at global, river basin and farm scales?

• What are water implications of climate mitigation measures?• What are the most promising measures in water management to

minimize agricultural vulnerability to climate change ? • What water related investments are needed and where?

GCMs

CC-related policies

WATER SCARCITY AND CLIMATE CHANGE

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

PREDICTING CLIMATE CHANGE IMPACTS AT SMALLER SCALES- Blue Nile, Ethiopia

• climate in the basin may become wetter and warmer in 2050s • low flows are likely to become higher• droughts are likely to become less frequent and severe

Runoff:-15 to +25% change

Precipitation:0 to 20% increase

Q90:-25 to +60% change

MAKING STORAGE “SMARTER” – storage continuum

All of the above

Planting crops

Direct,Buckets, pumps

dam outlets,pumps, off-take towers

Natural wetlands

Reservoirs

Ponds and Tanks

Aquifers

Soil Moisture

deep shallow

small large

SUBSURFACE SURFACE ACCESS

Increasing resilience Increasing resilience

Increasing capital costsIncreasing com

plexity of managem

entIncreasing environm

ental and social cost

Boreholes,deep /shallow wells, etc

EVALUATING CC ADAPTATION OPTIONS – the case of groundwater in India

Measurable criteria Small Surface Storage

Large Dams

Managed Aquifers

Water where needed 3 2 5

Water when needed 1 2 5

Level of water control 1 2 5

Non-beneficial losses –e.g. evaporation

-4 -2 -1

Protection against a single annual drought

1 2 5

Protection against successive droughts

-1 1 4

Ease of recovery during monsoon

5 4 3

Other

India

USA

W. Europe

China

VN, SL

Bang., Pak

Groundwater use in Asia Climate change and water storage alternatives

EVALUATING THE IMPACTS OF CLIMATE CHANGE POLICIES- the case of biofuels

• For all national biofuels’ plans to be implemented, 30 mill ha more land and 180 km3 more water will be necessary globally

• Some Individual countries (e.g. China and India) will not meet food and biofuel water demand

• Is it ethical to use crops to produce energy when 860 mill people are undernourished?

“USING” CLIMATE CHANGE TO HELP SOLVE OLD PROBLEMS-

data collection and sharing

• Observed hydrological data in the world are insufficient to meet climate cahnge challenges

• Many countries and regions remain poorly gauged • Data collection networks decline • Access to already collected data is limited

0

1000

2000

3000

4000

5000

6000

7000

8000

9000

1901

1905

1909

1913

1917

1921

1925

1929

1933

1937

1941

1945

1949

1953

1957

1961

1965

1969

1973

1977

1981

1985

1989

1993

1997

2001

2005

Years

Num

ber o

f Flo

w S

tatio

ns

2200 flow stations closed in 1980-2005 many had 30+ years of record

USAM.Norris, USGS

Example of declining networks Only 20 out 170 WMO member states share data

CONCLUSIONS

• Understanding of and adapting to existing climate variability is critical for adaptation to future climates

• Quantification of local climate change impacts is imperative for the design of adaptation measures. There may be potential beneficiaries of climate change too

• climate change brings back to the agenda conventional water management measures, like storage, but forces to re-think them as adaptation options

• climate change -related interventions, like buofuels, may have significant implications for agriculture and water management. They need to be evaluated

• climate change may be a new context which facilitate the solution old problems in the water sector, like data sharing.