Water Security and Climate Adaptation in Southern Africa Volume 1 Volume 1 Integrated Transboundary Water–Climate Management Tools Edited by NnenesiJ.S. Krüger A.Edited Kgabi by Charl Wolhuter Water Security and Climate Adaptation in Southern Africa Volume 1 Integrated Transboundary Water–Climate Management Tools Published by AOSIS Books, an imprint of AOSIS Publishing. AOSIS Publishing 15 Oxford Street, Durbanville 7550, Cape Town, South Africa Postnet Suite #110, Private Bag X19, Durbanville 7551, South Africa Tel: +27 21 975 2602 Website: https://www.aosis.co.za Copyright © Nnenesi A. Kgabi (ed.). Licensee: AOSIS (Pty) Ltd The moral right of the authors has been asserted. Cover image: Original design created with the use of free images. Free images used Free image used https://pixabay.com/photos/autumn-river-nature-water-trees-972786/ is released under Pixabay License. Published in 2020 Impression: 1 ISBN: 978-1-928523-82-6 (print) ISBN: 978-1-928523-83-3 (epub) ISBN: 978-1-928523-84-0 (pdf) DOI: https://doi.org/10.4102/aosis.2020.BK205 How to cite this work: Kgabi, N.A. (ed.), 2020, ‘Integrated Transboundary Water–Climate Management Tools’ in Water Security and Climate Adaptation in Southern Africa Volume 1, pp. i–224, AOSIS, Cape Town. Water Security and Climate Adaptation in Southern Africa ISSN: 2710-0987 Series Editor: Nnenesi A. Kgabi Printed and bound in South Africa. Listed in OAPEN (http://www.oapen.org), DOAB (http://www.doabooks.org/) and indexed by Google Scholar. Some rights reserved. This is an open access publication. Except where otherwise noted, this work is distributed under the terms of a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International license (CC BY-NC-SA 4.0), a copy of which is available at https:// creativecommons.org/licenses/by-nc-sa/4.0/. 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Water Security and Climate Adaptation in Southern Africa Volume 1 Integrated Transboundary Water–Climate Management Tools EDITOR Nnenesi A. Kgabi Science, Engineering and Technology domain editorial board at AOSIS Commissioning Editor Andries van Aarde, MA, DD, PhD, DLitt, South Africa Board Members J.E. (Joe) Amadi-Echendu, Professor and Doctor, Graduate School of Technology Management, Faculty of Engineering, Built Environment and Information Technology, University of Pretoria, Pretoria, South Africa John Butler–Adam, Doctor and Editor-in-Chief, South African Journal of Science, Academy of Science of South Africa, South Africa Tania Douglas, Professor, South African Research Chair in Biomedical Engineering and Innovation, University of Cape Town, South Africa H.S. (Manie) Geyer, Professor, Doctor and Director, Centre for Regional and Urban Innovation and Statistical Exploration, Department of Geography, Stellenbosch University, South Africa Igor Gorlach, Professor and Doctor, Professor Mechatronics, Nelson Mandela Metropolitan University, Port Elizabeth, South Africa Lech M. Grzesiak, Professor and Doctor, Dean of Faculty of Electrical Engineering, Warsaw University of Technology, Warsaw, Poland Yacob Malugetta, Professor and Doctor, Professor of Energy and Development Policy, University College, London, United Kingdom Steven Mutula, Professor and Doctor, Deputy Vice-Chancellor, University of KwaZulu-Natal, South Africa Refilwe Phaswana-Mafuya, Professor and Doctor, Deputy Vice-Chancellor: Research and Innovation. North-West University, Potchefstroom, South Africa Mokone J. Roberts, Doctor, Energy Research Centre, University of Cape Town, Managing Editor of the Journal of Energy in Southern Africa, South Africa Peer review declaration The publisher (AOSIS) endorses the South African ‘National Scholarly Book Publishers Forum Best Practice for Peer Review of Scholarly Books’. The manuscript was subjected to rigorous two-step peer review prior to publication, with the identities of the reviewers not revealed to the author(s). The reviewers were independent of the publisher and/or authors in question. The reviewers commented positively on the scholarly merits of the manuscript and recommended that the manuscript be published. Where the reviewers recommended revision and/or improvements to the manuscript, the authors responded adequately to such recommendations. Research Justification The scholarly theme of the book lends itself to the discipline of earth and atmospheric sciences, with a specific focus on water–climate studies. The book is a scholarly discourse by researchers in the natural sciences, including hydrologists, climate scientists, environmental engineers and water scientists. The purpose of the book is to address the limited complementarity between the water and climate studies, which is crucial in promoting scientific research that informs policy decisions and the implementation of water-security plans. The chapter contributions were sourced from researchers in the project – ‘Water Security and Climate Adaptation in Southern Africa’ at the North-West University, and the research chair network linked to the United Nations Educational, Scientific and Cultural Organization (UNESCO) Chair on Sustainable Water Research for Climate Adaptation in Arid Environments, based at the Namibia University of Science and Technology. The chapters were selected to represent water–climate models and policy research conducted in different river basins in arid and semi-arid environments. Therefore, the water–climate management tools highlighted in this book include General Circulation Models (GCMs), Coupled Model Inter-comparison Project Phase 5 (CMIP5), Soil and Water Assessment Tool (SWAT), Africa Flood and Drought Monitor (AFDM), Extreme Precipitation Events (EPEs), R ClimDex, Mixed Strategy Game Models, Standard Precipitation Indices (SPIs), Water Evaluation and Planning (WEAP) System, Penman Calculator and Saturated Volume Fluctuation (SVF). Four of the nine chapters in this book contain material representing substantial reworking of the primary research and modelling for higher degree studies done at the University of Zambia and the Namibia University of Science and Technology. One chapter is a review of previous studies, and the remaining eight are based on river basin research and modelling projects by researchers from different institutions. As a whole, the book contains more than 50% original content, not published before, and no part of the book has been plagiarised. Nnenesi A. Kgabi, Unit for Environmental Sciences and Management, Faculty of Natural and Agricultural Sciences, North-West University, Potchefstroom, South Africa Contents Abbreviations, Figures and Tables Appearing in the Text xv List of Abbreviations xv List of Figures xviii List of Tables xxiii Notes on Contributors xxvii Acknowledgements xxxvii Preface xxxix Chapter 1: A review of selected water–climate studies conducted in Tanzania, Southern Africa 1 Nnenesi A. Kgabi Abstract 1 Introduction 2 Methods or study approach 5 Data collection 5 Data analysis 6 Results and discussion 6 Water–climate management tools 6 The water–climate focus 8 Water security and related focus 8 Actual water–climate research activities 9 Link to global or national or local mitigation or adaptation plans 10 Concluding remarks 12 Acknowledgements 12 Chapter 2: Impact of climate change on water security in a semi-arid river basin 13 Yali E. Woyessa & Bruce N. Wilson Abstract 13 vii Contents Introduction 14 Methods or study approach 16 Description of the study area 16 Biophysical factors 16 Climate change modelling 20 Hydrological modelling 22 Model setup and input data 23 Model calibration 24 Results and discussion 24 Climate change modelling 24 Hydrological modelling 25 Impact assessment and implications for water security 30 Impact of climate change on future rainfall 32 Impact of climate change on water balance 35 Conclusion 37 Acknowledgements 38 Chapter 3: Effective utilisation of the Africa Flood and Drought Monitor 39 Nnenesi A. Kgabi, Dianah I. Irenge & Sunday A. Reju Abstract 40 Introduction 40 Methods or study approach 44 Study sites 44 Data collection and analysis 47 Results and discussion 47 Comparison of output from Africa Flood and Drought Monitor and the observation data from the National Meteorological Services 47 The Africa Flood and Drought Monitor data processing or generation process 51 Models involved in the information generation and the products 56 Concluding remarks 56 Acknowledgements 60 viii Contents Chapter 4: Water security and extreme precipitation indices of selected towns in Namibia 61 Nnenesi A. Kgabi, Sunday A. Reju & Dianah I. Irenge Abstract 62 Introduction 63 Methods/study approach 64 Description of study site 64 Data collection and quality control 64 Analysis methods 66 Results and discussion 68