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The role of virtual water transfer in water management. Arjen Hoekstra UNESCO-IHE, Delft, Netherlands (www.ihe.nl). Virtual water content of products. Definition of virtual water. - PowerPoint PPT Presentation
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Arjen HoekstraUNESCO-IHE, Delft, Netherlands (www.ihe.nl)
The role of virtual water transfer in water management
North America
Central America
Western Europe
Eastern Europe
FSU
Central and South Asia
South east Asia
Oceania
Southern Africa
Central Africa
North Africa
South America
Middle East
-1141-307-300-90-9-4-31317204242377984No Data
Net virtual waterimport, Gm3
Virtual water content of products
1 kg grain 1-2 m3 water
1 kg cheese 5 m3 water
1 kg beef 16 m3 water
Five hundred 32-MB chips
(2 gram each)
16 m3 water
Definition of virtual water
Virtual water is the water ‘embodied’ in a product, not in real sense, but in virtual sense. It refers to the water needed for the production of the product.
Assessing virtual water trade flows
Virtual water content of a crop
Crop water requirement (m3/ha) / Crop yield (ton/ha)
Virtual water content of a livestock product1. Virtual water content of the live animal2. Distribute this volume over the different products from
this animal
Virtual water trade flows
Trade volume (ton/yr) Virtual water content (m3/ton)
Basic data
Global trade data
United Nations Statistics Division, New York
Virtual water content Crop water requirements (m3/ha): CROPWAT (FAO) Crop yields (ton/ha): FAOSTAT (FAO)
Virtual waterHistory of the concept
1993-94 Introduction of the concept by Tony Allan
12/2002 International Expert Meeting on Virtual Water Trade, UNESCO-IHE, Delft, Netherlands
03/2003 Session on ‘Virtual Water Trade and Geopolitics’ at the 3rd World Water Forum, Japan
Virtual waterState of current knowledge
Three global studies on virtual water trade.
Some national studies on virtual water trade (Middle East, North Africa, Southern Africa, Japan, China).
Knowledge on economic, environmental, social and cultural implications of current virtual water trade is nearly absent.
Knowledge on how to use virtual water trade as a means to relieve pressure on world’s water resourcesce is very weak.
Global virtual water tradebetween nations (1995-1999)
Volume
billion m3/yr
Percentage
%
Crops and crop products
Livestock and livestock products
Industrial products
695
245
100
67
23
10
Total 1040 100
[Hoekstra, 2003]
Global virtual water tradebetween nations (1995-1999)
Volume
billion m3/yr
Percentage
%
Crops and crop products
Livestock and livestock products
Industrial products
695
245
100
67
23
10
Total 1040 100
[Hoekstra, 2003]
30% wheat17% soybean15% rice 9% maize 7% raw sugar 5% barley
Global virtual water tradebetween nations (1995-1999)
Volume
billion m3/yr
Percentage
%
Crops and crop products
Livestock and livestock products
Industrial products
695
245
100
67
23
10
Total 1040 100
[Hoekstra, 2003]
34% bovine meat16% bovine hides
and leather12% cow milk &
milk products
10% swine and its products
8% live bovine 4% sheep and
its products
Global virtual water tradebetween nations (1995-1999)
Volume
billion m3/yr
Percentage
%
Crops and crop products
Livestock and livestock products
Industrial products
695
245
100
67
23
10
Total 1040 100
[Hoekstra, 2003]= 16% of global water use!
Drawing a national‘virtual water trade balance’
1. How much water goes into the country in the form of imported products?
2. How much water leaves the country in the form of exported products?
Virtual water balance of the USA
Net export of
virtual water:
164 Gm3/yr
0.0E+00
5.0E+10
1.0E+11
1.5E+11
2.0E+11
2.5E+11
1995 1996 1997 1998 1999
Export Import
Total water withdrawals USA:
500 Gm3/yr
Available water resources:
2500 Gm3/yr
= 1/15 of available resources
Virtual water balance of the Thailand
Net export of
virtual water:
46 Gm3/yr
0.0E+00
5.0E+10
1.0E+11
1.5E+11
2.0E+11
2.5E+11
1995 1996 1997 1998 1999
Export Import
Available water resources:
179 Gm3/yr
= 1/4 of available resources
Virtual water balance of the Japan
Net import of
virtual water:
82 Gm3/yr
0.0E+00
5.0E+10
1.0E+11
1.5E+11
2.0E+11
2.5E+11
1995 1996 1997 1998 1999
Export Import
Virtual water balance of the China
Net import of
virtual water:
19 Gm3/yr
0.0E+00
5.0E+10
1.0E+11
1.5E+11
2.0E+11
2.5E+11
1995 1996 1997 1998 1999
Export Import
Water withdrawal:
550 Gm3/yr
Water availability:
2800 Gm3/yr
Export virtual water 17
Import virtual water 34
1409Annual virtualwater budget
Water footprint of China 1392
60% green water
40% blue water
China Virtual water balance (Gm3/yr)
Withdrawal559
Green wateruse 816
Blue water 2812
Precipitation6152
2524 Evapotranspiration (ET) from non-agricultural area
6152Annual real
water budget
River discharge 2253
China Real water balance (Gm3/yr)
ET 3340
National virtual water trade balances 1995-1999
Net virtual water import, Gm3
-900 - -500-500 - -100-100 - -10-10 - 00 - 1010 - 5050 - 100100 - 500No Data
Net virtual water export Net virtual water importTop-7 list of countries Top-7 list of countries
Gm3/yr Gm3/yr
USA 164 Sri Lanka 84
Canada 64 Japan 82
Australia 58 Italy 31
Argentina 52 South Korea 30
Thailand 46 Netherlands 25
India 34 Indonesia 23
France 22 China 19
....... ......
Period: 1995-1999
Virtual water Virtual waterexporters importers
1. France 1. Italy
2. Ukraine 2. Netherlands
3. Ireland 3. Spain
..... 4. Germany
5. Russia
6. Belgium-Luxembourg
7. Portugal
......
Europe
Net export: 44% of Rhône runoff
Net import: 67% of Po runoffNet import: 36% of Rhine runoff
Virtual water trade balances of thirteen world regions (1995-1999)
North America
Central America
Western Europe
Eastern Europe
FSU
Central and South Asia
South east Asia
Oceania
Southern Africa
Central Africa
North Africa
South America
Middle East
-1141-307-300-90-9-4-31317204242377984No Data
Net virtual waterimport, Gm3
Arrows show trade flows >100 Gm3
Ranking of regions (1995-1999)
Gross virtual water import Gross virtual water export
Gm3 Gm3
Central-South Asia 1184 North America 1317
Western Europe 643 South America 415
North Africa 276 Oceania 363
Middle East 261 Southeast Asia 347
Southeast Asia 257 Western Europe 266
....... ......
the virtual water concept:what is the practical use?
1. Virtual water: an alternative source of water
Many national economies depend on (net) import of virtual water. For the period 1995-99:
Jordan 80% Italy 20%
Netherlands 80% Egypt 20%
Japan 40% South Africa 20%
Tunesia 50% China 4%
2. Virtual water trade: global water savings
Much of the international virtual water trade takes place from nations where water productivity is relatively high to nations where water productivity is relatively low.
global real water saving!
450 billion m3/yr saving due to global food trade= 8% of global water use for crop production!
[Oki et al., 2003]
3. Virtual water trade: an additional means to improve water use efficiency
Local water use efficiency
user level
Technology, water price, environmental awareness of the water user
Water allocation efficiency
national / basin level
Value of water in its alternative uses
Global water use efficiency
global level
Virtual water trade between water-scarce and water-abundant regions
4. Virtual water trade: an alternative to real interbasin water transfers
Proposed large inter-basin water transfers: China India South Africa Spain
Alternative: Trade of water intensive products from water-rich to
water-poor regions
5. Virtual water storage: an alternative for dams
[Renault, 2003]
0
1000
2000
3000
4000
5000
6000
7000
Global virtual waterstorage
Global capacity of realwater reservoirs
bil
lio
n m
3
living cattle
meat, oilsugar
grains
6. Calculation of national water footprints
m3/yr per capita
China, India, Indonesia 500
Mexico 1000
Netherlands, Belgium 2000
Conclusion
15-20% of the global water use is not used for domestic consumption but for export (in virtual form).
This is the global percentage; the situation strongly varies between countries.
The crude estimates show that it is very relevant to carry out virtual water analysis in any national or regional water policy study.
Future research agenda
Accounting Develop a common methodology and standards for virtual water accounting
Diets and footprints Understand the relation between consumption patterns, water needs, water scarcity and resulting virtual water trade
Trade Analyse current trade flows, trade relations and dependencies; and develop projections under global change scenarios
Application Enhance understanding of the implications of application of the virtual water concept on national and basin level
Political impacts Enhance understanding of virtual water trade on the position of sovereign nations and the political processes underlying decisonmaking
Awareness and debate Create a better understanding of consequences of conscious application
Thank you