Willem Ligtvoet, January 12 1 Climate change and Water Management Policy options for the future

Willem Ligtvoet, January 12 Climate Change and Water Management 2 Climate change – dealing with uncertainties  Temperature rise  Sea level rise  Precipitation patterns  River discharges – averages and peak discharges  Storm surges and hurricanes

Willem Ligtvoet, January 12 Climate Change and Water Management 3 Risks with respect to water management  Changes in flood risks: coastal and river areas  Changes in water availability and drought risks  Salinization of deltas  Increased risks of urban flooding According to IPCC effects of climate change may be prominent in second half of 2100 (IPCC, 2008)

Willem Ligtvoet, January 12 Climate Change and Water Management 4 Trend in weather-related disasters Data do not allow conclusions about relationship climate change and disasters -Corrected for population growth and economic growth there is a stabilization Source: Visser et al., in prep Population growth by 1/3 up to 9 billion -Further economic growth  Vulnerability increases  Water demand increases

Willem Ligtvoet, January 12 Climate Change and Water Management 5 World water resources  Salt water1,05 billion km397,5%  Freshwater 35 million km3 2,5% Available for use <1 % Source: UNEP; WWAP

Uncertainties availability  demand: tipping points Resource variability time water demand Options: -Increase resource *water harvesting *de-salinization - Increase resource efficiency *households *industries *agriculture Result: - Reduced vulnerability - Buying time water quantity

Freshwater use world wide  Households 8%  Industry22%  Agriculture70% 20% of agricultural area => 40% of food production 80% agricultural area rainfed Source: UNEP; WWAP Irrigation increases crop production factor 2-5

Relevant drivers increasing pressure on water  Population growth up to 9 billion people with 70% in cities  Economic growth and increasing wealth  Growth of food production (irrigation, nutrients, pesticides)  Changes in diet: more meat increases water demands  Globalisation and liberalisation => shift of food production from dry areas to wet areas  Biomass production: water demand >> rice and wheat  Climate change

Water demand increases Source: PBL in OECD

Population lacking access to improved watersupply UrbanRural Source: PBL in OECD

Population lacking access to improved sanitation UrbanRural Source: PBL in OECD UrbanRural

Diet change increases water demand water use/kg  Cattle15 m3  Sheeps/goats10 m3  Poultry 6 m3  Rice 3 m3  Wheat 1,5 m3  Citrus 1 m3 Source: FAO

Shift of food production increases water stress Source: PBL in OECD; WUR Saoudi Arabia -> Ethiopia food Soedan China, Korea, Japan -> Africa food, biomass Brasil -> Mozambique biomass sugercane Europe food/biomass

Water embedded in complex interactions Urban developments Rural & Nature developments Capital driven agriculture water land conversion labour emissions food migration capital land conversion capital food …. Export - food - biomass international networks Food import national & foreign investors Water and food- security not only a matter of water

Role of water management  Main drivers out of reach  Water needs to be integrated in economic analyses - optimizing crop per drop (production/m3, $$ /m3) - $$/m3 agriculture  $$/m3 competing activities - $$ ecosystemservices - …  Contribution to fair sharing: between nations, between people, between sectors (nature, ecosystems)  Basis: analysis on scale of river basins!

Integrated water basin management

Interactions upstream/downstream

+ complex thematic interactions Land use Water use

Wide variety of policy instruments - Information – behavioural changes - Standards waterquality * nutrients * other emissions - Water permits, water rights - Land use planning - Technology * improving resource eff. * de-salinisation - Cutting perverse subsidies - Introduce positive subsidies -…..

Willem Ligtvoet, January 12 Climate Change and Water Management 20 Future challenges Strategic -Integration of water and climate in economical and political strategies -Powerfull economical analyses on river basin scale for informed decisions on water allocation and use (River Basin Committees  National governments) -Water is cross-cutting issue: supra-sectoral approach required within context of water basins -Guiding principles: sustainable use and fair sharing Technology -Sharp improvement of resource efficiency especially in agriculture -De-salinization based on renewable and cheap energy -Water-harvesting techniques -…………

Willem Ligtvoet, January 12 Climate Change and Water Management 21 Enormous geographical differences No silver bullets – area-specific analyses and approaches needed Physical system Economic system Political/societal system What?How?

Willem Ligtvoet, January 12 Climate Change and Water Management 22