Transcript Adaptation options to climate change and variability on water

ADAPTATION OPTIONS TO CLIMATE
CHANGE AND VARIABILITY ON WATER
RESOURCES IN AFRICA.
Jonathan I. Matondo
UNIVERSITY OF SWAZILAND
LAYOUT OF THE PRESENTATION
• Introduction
• Current status of climate change and
variability
• Impact of climate change and variability on
– water resources in Africa
– Social, economic and environmental
consequences
LAYOUT OF THE PRESENTATION CONT..
• Adaptation options
– Short-term adaptation options
– Long term adaptation options
– The need for regional cooperation
• Water policy proposal for Africa
INTRODUCTION
• Climate will always change due to natural
forcing of eccentricity
• The natural green house gases have kept
the earth’s atmosphere some 30o Celsius
hotter, than it would otherwise be, making it
possible for humans and other living things
to exist on earth.
• The global green house gas emissions due
to anthropogenic activities have increased
since pre-industrial times
INTRODUCTION CONT..
• Temperature across Africa are expected to
increase ranging from 0.2oC per decade
(low scenario) to more than 0.5oC per
decade (high scenario)
• This warming is greatest over the interior
of semi-arid margins of the Sahara, central
and southern Africa.
CURRENT STATUS OF CLIMATE
CHANGE AND VARIABILITY
• Mean annual rainfall has decreased by 20–49%
in the Sahel between the periods 1931–1960
and 1968–1997
• generally a mean annual rainfall decrease
ranging from 5–10% across the rest of the
continent has been reported.
• Africa has experienced at least one major
episode in each decade in the past 30 years.
• In Eastern Africa there were serious droughts in
1973-74, 1984-85, 1987, 1992-94, 1999-2000,
2003 and 2005.
CURRENT STATUS OF CLIMATE
CHANGE AND VARIABILITY CONT..
• The last drought in the Sahelian persisted
for decades, from 1972-73 to 1983-84. It
caused major damage to the environment
and loss to human life.
• In Southern Africa, sever droughts as
recorded in 1967 – 73, 1981-83, 1986/87,
1991/92, 1993/94, 2001/02, 2003 and
2005/06).
Niger;
Change ?
Rapid/gradual
Persisted
Blue Nile;
Gradual
Decadel
variability
Lake
Victoria;
Rapid
Slow return ?
1900
1920
1940
1960
1980
2000
CURRENT STATUS OF CLIMATE CHANGE
AND VARIABILITY CONT..
• West Africa has also experienced droughts
in the 1980s and 1990s, and 2000s
• The continent has also experienced severe
floods.
– The floods of 1999-2000 in Nigeria, South
Africa and Mozambique
– The floods of 2003 and 2006 in East Africa
– The floods of 2008 in Southern Africa
:
Gradual disappearance of Mt. Kilimanjaro glaciers
IMPACT OF CLIMATE CHANGE AND
VARIABILITY ON WATER RESOURCES
• GCMs simulations predict
– A 10 to 20 per cent drop in rainfall in Northwestern
and Southern Africa by 2070
– River water levels are expected to drop below 50 per
cent.
– Table 2 shows precipitation and runoff
changes due to climate change.
• 230 million of Africa’s population will be facing
water scarcity by 2025
• 460 million people in water stressed Countries
Table 2: Estimates of range of changes (in
percent) in precipitation, potential
evaporation, and runoff in African rivers
(IPCC, 2001; Matondo et al. 2004; IPCC,
2007)
Basin name
Nile
Niger
Volta
Schebeli
Congo
Ogooue
Rufiji
Zambezi
Limpopo
Orange
Pangani
Ruvu
Rivers in Swaziland
Change in
precipitation (%)
10
10
0
-5 to 18
10
-2 to 20
-10 to 10
-10 to -20
-5 to -15
-5 to 5
10
Change in potential
evaporation (%)
10
10
4 to -5
10 to 15
10 to 18
10
20
10 to 25
5 to 20
4 to 10
Change in runoff (%)
0
10
0 to -15
-10 to 40
10 to 15
-20 to 25
-10 to 20
-30 to -40
-25 to –35
-10 to 10
-6 to -9
-10
-5 to 5
IMPACT OF CLIMATE CHANGE AND
VARIABILITY ON SOCIO-ECONOMIC AND
THE ENVIRONMENT
• Reduced precipitation is expected to cause a decline
in agricultural production thus food insecurity.
• Globally, 80-120 million people are at risk of hunger;
70 to 80 per cent of these are expected to be in
Africa, by 2080.
• Most rivers in Africa are International. The reduction
in the river flows is potential for conflict.
• Due to expected sea level rise
– It is estimated that 70 million people will be at
risk from coastal flooding by 2080
– large cities such as Banjul, Lagos, Alexandria,
Dar es Salaam, Cape Town, Maputo etc. could
be in a verge of being submerged
IMPACT OF CLIMATE CHANGE AND
VARIABILITY ON SOCIO-ECONOMIC AND
THE ENVIRONMENT CONT..
– Areas considered now dry humid, semi-arid
and arid will become semi-arid, arid and
desert respectively under expected climate
change.
– People in drought prone areas of southern
Africa to abandon agriculture permanently in
the next 50 years.
– The frequency of extreme events (droughts
and Floods) are expected to increase
• This will increase the damage to infrastructures,
the environment and loss to human life.
• This will also increase the financial burden to most
African governments.
SOCIAL, ECONOMIC AND ENVIRONMENTAL
CONSEQUENCES CONT..
FLOODING IN WESTERN KENYA
ADAPTATION OPTIONS
• Short-term adaptation options
– Efficient use of existing water resources
– Recycling of wastewater
– Rainwater harvesting
– Use of groundwater
– Implementation of IWRM
• Long-term adaptation options
– Construction of storage and inter-basin water
transfers
– Building desalination plants
EFFICIENT WATER USE
CATCHMENT SWAZILAND)
(MBULUZI
Discharge (mm/day)
1.20
1.00
0.80
0.60
0.40
0.20
0.00
-0.20
Oct
Nov Dec Jan Feb Mar Apr May Jun
Jul
Aug Sep
Months
OBSERVED
UKTR-HighN
UKTR-HighE
RAIN WATER HARVESTING
I
Sand Dam filled with water in Muthetheni,
Machakos district Kenya
RAINWATER HARVESTING CONT..
• Sand dam in Kenya
RAINWATER HARVESTING CONT…
ADAPTATION OPTIONS CONT..
• Need for cooperation
– Africa has 61 international river basins shared
by two or more countries.
• Therefore, there is a great need of cooperation
among riparian states in order to ensure that the
available resources are used beneficially and
equitably.
• The planning, development and management of
shared water courses requires the development of
water sharing agreements/treaties.
• The implementation of IWRM requires the
formation of river basin institutions and
agreements.
ADAPTATION OPTIONS CONT..
• Need for cooperation
– Examples
• ) SADC Protocol on shared water courses
• Senegal River agreement between Mali,
Mauritania and Senegal
• Nile river basin initiative
• Komati river (South Africa, Swaziland and
Mozambique
ADAPTATION OPTIONS CONT..
• Need for cooperation cont..
– The benefits of Regional cooperation are:
• Cooperation can enable better environmental management,
providing benefits to the river, and underpinning all other
benefits that can be derived.
• Cooperation can yield major benefits from the river including
increased irrigated agriculture and hydropower generation
• Cooperation will result in economic benefits associated with
reduced tension among riparian states.
• Watershed management and water storage in the major river
basins in Africa (Congo, Niger, Nile, Zambezi etc.) would
generate hydropower, flood control and irrigation benefits.
ADAPTATION OPTIONS CONT..
• Need for cooperation cont..
– International rivers can be catalyst agents, with
cooperation that would yield benefits from the river
and reduce costs because of the river, paving the way
to much greater interaction between states, such as
the movement of labor, goods and services and thus
yielding benefits beyond the river.
– The potential benefits of closer integration in water
planning, development and management are strongly
related to creating opportunities for improving the
prospects for growth and prosperity in all the regions
in Africa.
ADAPTATION OPTIONS CONT..
• Need for cooperation cont..
– Regional cooperation in energy and water could have
huge gains for regions in Africa by providing improved
energy supply for economic growth.
– Cross-border management of water resources and
data and information exchange could help control
flooding across riparian states and improve the water
availability.
PROPOSED WATER POLICY
– International water resources shall be shared in
accordance to the Dublin-Rio principles.
– Establishment and/or strengthen existing river
basin institutions national/international should
be considered as a pre-requisite for the
implementation of IWRM.
– Climate change adaptation options to be
mainstreamed in national development action
plans
– Integrated Flood Management (IFM) should be
applied in flood prone areas (restrictions to be
limited to structural development only).
PROPOSED WATER POLICY CONT..
– The environment is a legitimate user of water.
Therefore water allocation shall insure that a
minimum reserve is allowed for the protection
of the environment (inflow water requirement).
– Water resources development shall at all
times ensure environmental protection in
compliance with ratified international
laws/conventions and standards.
PROPOSED WATER POLICY CONT..
– Gender mainstreaming in the management of water
resources shall be encouraged in line with the DublinRio principles.
– Exchange of experiences including best practices on
farming should be promoted to ensure that
watersheds are not degraded.
– Encourage rainwater harvesting techniques
– Strengthen National and Regional capacities for
information gathering and monitoring.
– Strengthen regional cooperation and encourage
exchange of data and information
AFRICA IS ENDORWED WITH RENEWABLE
RESOURCES SUCH AS..
– Water resources
– Solar energy
– Wind energy
• WHAT IS REQUIRED IS THE
INFRASTRUCTURE(S) TO HARNESS
THE ABOVE RESOURCES
• THANK YOU
• AHSANTE SANA
• SIYABONGA KAKHULU