Mahmoud Abu-Zeid and I. A. Shiklomanov Tenth IMO lecture WATER RESOURCES AS A CHALLENGE OF THE TWENTY-FIRST CENTURY World Meteorological Organization Weather • Climate • Water WMO-No.959 2003 © 2004, World Meteorological Organization ISBN: 92-63-10969-9 NOTE The designations employed and the presentation of material in this publication do not imply the expression of any opinion whatsoever on the part of the Secretariat of the World Meteorological Organization concerning the legal status of any country, territory, city or area, or of its authorities, or concerning the delimitation of its frontiers or boundaries. CONTENTS Page FOREWORD........................................................................... V WATER RESOURCES AS A CHALLENGE OF THE TWENTY-FIRST CENTURY by Mahmoud Abu-Zeid (Minister of Water Resources and Irrigation of Egypt, President of the World Water Council) . 1 SUMMARY............................................................................ 1 1. THE HARD FACTS . 1 1.1 Water scarcity and water poverty levels . 2 2. MAJOR GLOBAL WATER CHALLENGES . 2 2.1 Meeting basic needs . 3 2.2 Food security . 3 2.3 Protecting ecosystems . 3 2.4 Sharing water resources . 3 2.5 Managing risks . 3 2.6 Valuing water . 3 2. 7 Governing water wisely . 4 3. INTEGRATED WATER RESOURCES MANAGEMENT . 4 4. GOVERNANCE . 5 5. MAJOR ISSUES . 5 5.1 Impact of climate change on water resources . 6 5.2 Transboundary river basins . 7 5.3 Public-private partnerships . 8 5.4 The role of dams in development . 9 6. INTERNATIONAL COMMITMENTS AND TARGETS . 9 6.1 United Nations Water Conference (Mar del Plata, March 1977) . 9 6.2 The WEHAB initiative . 9 6.3 World Food Summit (Rome, 2002) . 10 6.4 World Summit on Sustainable Development (Johannesburg, 2002) . 10 6.5 Third World Water Forum (Kyoto, March 2003) . 11 7. CONCLUSIONS.................................................................... 11 8. REFERENCES . 12 WATER RESOURCES AS A CHALLENGE OF THE TWENTY-FIRST CENTURY by Professor A.I. Shiklomanov State Hydrological Institute, St Petersburg, Russian Federation 13 SUMMARY............................................................................ 13 CHAPTER I-INTRODUCTION . 16 CHAPTER 2-THE WORLD'S WATER RESERVES; TYPES OF WATER RESOURCES . 19 iv WATER RESOURCES AS A CHALLENGE OF THE TWENTY-FIRST CENTURY Page CHAPTER 3-REPLENISHABLE WATER RESOURCES . 22 3.1 General approaches to assessment methodology . 22 3.2 The World Hydrological Network: its present state, problems of information exchange and generalization . 24 3.3 Basic data and assessment methods used by the SRI . 31 3.4 Water resources of river basins . 34 3.5 Water resources in different natural and economic regions and continents . 35 3.6 Water resources in selected countries . 44 CHAPTER 4-RIVER WATERS INFLOW TO THE OCEANS . 50 4.1 Water resources and inflow of river waters into oceans . 50 4.2 Climate changes and river water discharge dynamics into the Arctic Ocean . 53 CHAPTER 5-WORLD WATER USE: CURRENT STATE AND TRENDS . 61 5.1 Contributory factors and the part played by economic activities in a world of changing water resources 61 5.2 Water use for community needs . 68 5.3 Water use by industry and for thermal power needs . 70 5.4 Water use in agriculture . 73 5.5 Reservoirs as freshwater users . 77 5.6 Method of assessing and forecasting water use and availability . 80 5.7 World water use dynamics . 89 CHAPTER 6-WATER RESOURCES, WITHDRAWAL AND AVAILABILITY; WATER RESOURCES SHORTAGES . 106 CHAPTER 7-WORLD WATER RESOURCES IN THE EARLY TWENTY-FIRST CENTURY, GIVEN IMPROVED EFFICIENCIES IN FRESHWATER USE . 114 7.1 Scenarios under "The World Water Vision Project" . 114 7.2 Sustainable development scenario (SRI) . 116 7.3 Water use, stress on water resources and water availability in the world under the Sustainable Development Scenario . 117 CHAPTER 8-THE EFFECTS OF MAN-MADE CLIMATE CHANGES ON WATER RESOURCES AND WATER USE . 121 8.1 The influence of water use on the characteristics of regional and global water circulation . 121 8.2 The influence of man-made changes in atmospheric gases on climate and water resources . 122 CHAPTER 9-HOW TO DEAL WITH WATER RESOURCES DEFICITS: SOME TECHNOLOGICAL, SOCIO-ECONOMIC, FINANCIAL AND ECOLOGICAL ASPECTS . 131 9.1 Regulation of river flow . 131 9.2 Secular freshwater reserves . 131 9.3 Desalination of saline and brackish waters . 132 9.4 Precipitation enhancement . 133 9.5 Geographical diversion of water . 133 9.6 Freshwater savings . 134 CHAPTER IQ-CONCLUSIONS . 136 REFERENCES.