CLIMATE CHANGE AND WATER
RESOURCES IN SOUTHERN AFRICA: Studies on Scenarios, Impacts,
Vulnerabilities and Adaptation
Report No. 1430/1/05
2005
EXECUTIVE SUMMARY
BACKGROUND
A focus on potential impacts of climate change on the water sector of
southern Africa (in the context of this report, made up of the Republic
of South Africa together with Lesotho and Swaziland) was triggered by a
series of activities and events in the first three years of the new
millennium which included the World Summit on Sustainable Development,
the Intergovernmental Panel on Climate Change reports in 2001, the
third World Water Forum, as well as active South African participation
in the International Geosphere-Biosphere Programme and Dialogue on
Water and Climate, among others. Additionally, there was the
realisation that perturbations in climate parameters, particularly of
rainfall, were largely amplified by the hydrological system and that if
climate changes were to manifest themselves in the manner which
international science was predicting, it would add a further layer of
concern to the management of southern Africa’s already high
risk and stressed water sector, with potential implications to the
entire region’s socio-economic well-being, but particularly
that of the poor.
These concerns culminated in the Water Research Commission’s
soliciting a two-year research project in mid-2002 titled
“Climate
Change and Water Resources in South Africa: Potential Impacts
of
Climate Change and Mitigation
Strategies”
The project was awarded to a consortium of four South African
universities, viz. KwaZulu-Natal (lead organisation), Cape Town,
Witwatersrand and Pretoria, within each of which specialist expertise
and international experience existed in one or more of climate scenario
development, impacts modelling and/or the human dimension and climate
change.
PROJECT OBJECTIVES
This research project set out with five main objectives, some of them
with sub-objectives. These are listed below with, in each
case, a short reference to indicate in which chapter(s) of the project
report the objective/sub-objective was addressed.
- Objective
1: The Development of Plausible Climate
Change Scenarios for Southern Africa
- Sub-Objective 1:
Evaluating the
Envelope of Future Climate Projections, Characterising the Uncertainty
and Placing Quantifiable Error Bars on the Regional Projections
- Sub-Objective 2:
Investigating
the Hemispheric-Scale Dynamical Responses to Greenhouse Gas Forcing in
the Context of Southern Africa, as Simulated by Different GCMs
- Sub-Objective 3: Analysis
of
Southern African Regional Dynamics and Feedbacks in the Context of
Climate Change
- Sub-Objective 4:
Empirical vs
RCM-Based Downscaling
- Sub-Objective 5:
Historical
Trends and Variability.
These sub-objectives are
all
addressed in Chapters 2
- 4, with sub-objective 5 further evaluated in
Chapters 15 - 19,
while Chapter 5
synthesises the findings of the
preceding three chapters.
- Objective
2: Investigation
of the Potential Impacts
of Climate Change on Hydrological Responses and Associated Water
Resources
- Sub-Objective 1: Design
and
Refinement of an Interlinked Quaternary Catchment Level Database for
Southern Africa for Application with Daily Hydrological Modelling under
Present and Future Climate Scenarios
- Sub-Objective 2:
Selection of a
Suitable Daily Hydrological Modelling System
- Sub-Objective 3:
Assessment of
a Range of Impacts of Climate Change on Hydrological Responses
- Sub-Objective 4:
Re-Application
of Above Impact Studies to the Thukela Catchment, as a Detailed Study
Area.
Chapter 6
introduces the
southern African hydrological “landscape” upon
which climate change would be superimposed. Chapters 7 and 8
cover the first 2 sub-objectives, while the impacts studies per se make
up Chapters 9 - 11.
In Chapters 12 - 14
three additional case studies
on potential impacts of hypothetical, but plausible, future climate
scenarios on hydrological responses in southern Africa are presented.
- Objective
3: Investigation of
Possible Water Related Socio-Economic Impacts of Climate Change in the
Thukela Catchment and Factors Contributing to Future Risk
This objective is
covered in
Chapters 21 - 25
by first providing a conceptual framework on
vulnerability, adaptive capacity, coping and adaptation (Chapters 21
and 22),
followed by three case studies (Chapters
24 and 25)
with
emphasis on research undertaken in the Thukela catchment.
Beyond the contract obligations, a study on perceptions of climate
change was carried out among different stakeholders in the water sector
(Chapter 23).
- Objective
4: Recommendations on Some Strategies to
Adapt to, and Cope with, Water-Related Impacts of Potential Climate
Change
While Chapter 21
already
addresses many aspects of coping and adaptation, a short overview of
South African policy documents on climate change with respect to water
resources (Chapter 26)
prefaces a longer chapter, Chapter
27, which
addresses broader issues of adaptation in the water sector and provides
more specific conclusions of South African stakeholders with regard to
policy/legal instruments, institutional/managerial issues and
research/monitoring needs.
- Objective
5: Detection of Effects of Climate Change
and Recommendations on Appropriate Monitoring Systems for its Detection
- Sub-Objective 1: Changes
Already Evident
- Sub-Objective 2:
Monitoring
Systems for Detection.
The first of these
sub-objectives is reviewed and researched in depth in Chapters 15 - 19
in a southern African context, while the second is evaluated in terms
of southern Africa’s rainfall network in Chapter 20.
All objectives set out at the commencement of the project, plus some
additional ones, have been met and are reported upon, setting the scene
for addressing more practical issues on how to cope with, legislate for
and adapt to, issues related to climate change in the southern African
water sector.
PROJECT OUTCOMES
The outcome of this project is this Report titled
“Climate
Change and Water
Resources in Southern Africa: Studies on Scenarios,
Impacts, Vulnerabilities
and Adaptation”.
The Report of 470 pages has been written as 29 chapters in 9 sections
which reflect the major objectives of this study. The sections are as
follows:
- Section
A:
Executive Summary, Table of Contents and Glossary of Terms
- Section
B:
Background to the Project
This consists of a single chapter
providing background concepts as well as the history of, and rationale
behind, the project.
- Section
C:
Development of Plausible Climate Change Scenarios for
Southern Africa
Four chapters provide the conceptual
foundation and uncertainties to the various downscaling approaches
adopted, which provide the project with future climate scenarios.
- Section
D:
An Investigation of the Potential Impacts of Climate Change
on Hydrological Responses and Associated Water Resources over Southern
Africa
This section is made up of nine chapters
covering the current hydrological “landscape” in
southern Africa, the hydrological model selected, the databases which
are used as a framework for the impact studies, the impact studies per
se at the scales of southern Africa and that of a designated Water
Management Area, viz. the Thukela catchment, and some case studies.
- Section
E:
Detection of Climate Change in Southern Africa
The six chapters making up this section
consist first, of a review of, and a description of methods for,
detecting climate change, followed by studies on detecting changes in
temperature, hydrological responses and rainfall as well as an
evaluation of the southern African rainfall station network in regard
to detection.
- Section
F:
Vulnerabilities and Sensitivities of Communities to Climate
Risks
Five chapters make up this section,
starting with two chapters on the conceptual framework on
vulnerability, adaptive capacity, coping and adaptation, followed by a
survey on perceptions of climate change held by different stakeholders
in South Africa, a case study on climate change and water poverty and a
chapter on case studies on climate and development with regard to
farming communities - one operating at small-scale and the other at a
large-scale.
- Section
G:
Adapting to Climate Change in South Africa
The last technical section of two
chapters focuses on policy in regard to climate change and the water
sector in South Africa and on adaptations to climate change by the
water sector.
- Section
H:
Synthesis and Recommendations for Future Research
Take-home messages from the project are
highlighted and, based on the outcomes of this project, some
recommendations are made for future research.
- Section
I:
Technology Transfer and Capacity Building
This section presents the activities of
the project team in the fields of relevant publications, workshops
attended, presentations made and students trained over the duration of
the project from 2003 to mid-2005.
The various chapters, which are of different lengths and at different
technical/conceptual levels, are presented as “independently
interdependent” entities, with each chapter standing on its
own, but forming an important component “link” in
the “chain” that makes up the entity of this
project. With each chapter “standing on its own”,
it goes without saying that certain issues are covered in more than one
chapter.