Water and Climate Change in Africa

1. Water and Climate Change in Africa Raffaello CervigniThe World Bank

2. Key Messages • The present: water management is a major constraint to Africa’s development • The future: climate change will make those constraint even more severe • The opportunity: climate change will increase the urgency of reforms and investments that would be important anyway • The challenge: we need both more knowledge, and more resources

3. The present

4. Challenging natural conditions Risk of recurrent drought High variability and low quantities for much of the continent

5. Frequent extreme weather events

6. Hydrological variability has huge impacts on poverty & livelihoods Relationship holds even in diverse middle income economies with substantial water storage infrastructure e.g. Morocco

7. Under present conditions (water storage, agricultural development, transport infrastructure etc), hydrologic variability reduces potential economic growth in Ethiopia by 38% and increases poverty by 25% A single drought over a 12-year period will decrease average GDP growth rates by 7-10% Inability to smooth water availability has multi-sectoral implications

8. Countries across continent already facing different kinds of water crisis Under-use in SSA, limited margins in North Africa

9. Water storage south of the Sahara is woefully under-developed

10. Water management in Africa is particularly challenging, because international river basins are predominant

11. The future

12. What is expected to change? • Temperature: • Expected to increase 2°- 6°C (over next century) with greatest impact over the semi-arid margins of the Sahara and central southern Africa and least in equatorial latitudes and coastal environments. • Precipitation: • Projected future changes in mean seasonal rainfall in Africa are less well defined.

13. Severe, but diverse impacts Percent change in run-off: multi-model average for the winter and summer precipitation (A1B SRES scenario) Reduction of 20 to 30% by 2050 Increaseof 20 to 30% by 2050 Source: Milly et al (2005), published in Nature

14. In water-scarce countries, agriculture will change • Rain-fed agriculture will become less reliable • Water allocations to agriculture will fall significantly • Urban use will take priority and urban populations growing • New irrigation schemes will have to be designed for lower water availability • Less surface water will encourage users to use groundwater • Controlling this is a highly complex institutional challenge • Reduced water availability in agriculture increases dependence on trade (high value crops for export, import of staples)

15. The opportunity

16. When countries can smooth consumption, agriculture becomes much more stable

17. Improved monitoring, assessment of water balance Improved planning and allocation processes, including internationally Strengthening institutions to manage water Investments Actions needed will become all the more important

18. It will become all the more important to review Policies that promote activities that are particularly vulnerable to precipitation E.g. subsidies for rainfed wheat production in North Africa Plans for new infrastructure where institutions are not yet ready to generate the potential benefits There will be no substitute for reform

19. The challenge

20. ECHAM4 2040-2069 HADCM2 2040-2069 CSIRO 2040-2069 CGCM1 2040-2069 GFDL 2010-2049 NCAR 2010-2049 CCSR 2040-2069 Improving knowledge for better planning

21. Mobilizing resources for storage management

22. The door may be opening, provided . . . . Political attention internationally Consensus at national and local level Climate change can be an opportunity