THE VULNERABILITY OF AFRICAN MAJOR COASTAL CITIES UNDER
EXPECTED CLIMATE CHANGE
INTRODUCTION
The African coast line is about 26,000 km (16,000 mi) long. Major cities that lie along the
African coastline to name a few are: Cape Town, Durban, Maputo, Dar es Salaam, Kinshasa,
Alexandria, Casablanca, Abidjan, Accra and Lagos. Sea-level rise as an impact of human-
induced climate change has significant implications to low-lying coastal areas and beyond. The
coastal zone contains valuable ecosystems and typically has higher population densities than
inland areas (Small and Nicholls, 2003; McGranahan et al., 2007). Additionally, it generates
significant amounts of economic activity contributing to national wealth (Bijlsma et al., 1996;
Sachs et al., 2001). In physical terms the major direct impacts of sea-level rise include
inundation of low-lying areas, shoreline erosion, coastal wetland loss, saltwater intrusion, higher
water tables and higher extreme water levels leading to coastal flooding (Leatherman and
Nicholls, 1995). Human-induced pressures on the coastal zone (such as growing population,
water abstraction, and alteration of the hydrological regime including the damming of sediments)
will exacerbate projections the effects of sea-level rise (Nicholls et al., 2007). However, due to
uncertainties in future and a lack of systematic data, these factors cannot be fully considered in
this report. Hence, the main issue addressed in this report is sea-level rise and its effects on
coastal areas. Table 1 shows the population of major coastal African cities.
Table 1. African Coastal cities with their corresponding population (2017)
City Country City Population Urban population
Alexandria Egypt 3806300 4345800
Casablanca Morocco 3344300 3344300
Abidjan (Ivory Coast) 3310500 3972300
Kinshasa DRC 6301100 7527500
Cape Town South Africa 2686000 3086600
,Dar es Salaam Tanzania 2456100 2456100
Durban South Africa 2354900 2354900
Tripoli Libya 1890600 2271800
Algiers Algeria 1696000 3815900
Accra Ghana 1605400 2756100
Mogadishu Somalia 1183100 1183100
Maputo Mozambique 1088100 1639300
Port Harcourt Nigeria 1053900 1190600
Freetown Sierra Leone 1032100 1032100
Port Elizabeth South Africa 833900 1047600
Douala Cameroon 1239100 1449400
Conakry Guinea 1595800 1595800
Dakar Senegal 2384000 2384000
Anthropogenic greenhouse gases warming up has been considered to be the major potential
mechanism of climate change over the next few hundred years. A number of gases that occur
naturally in the atmosphere in small quantities are known as “greenhouse gases”. Water vapour
(H2O), carbon dioxide (CO2), ozone (O3), methane (CH4), and nitrous oxide (N2O) trap solar
energy in much the same way as do the glass panels of a greenhouse or a closed automobile
(IPCC, 1990). It has been established that the climate change in the next 100 years will be due to
anthropogenic activities (IPCC, 2001).
Human activities, however, are now raising the concentrations of these gases in the atmosphere
and thus increasing their ability to trap energy. The global greenhouse gas emissions due to
anthropogenic activities have increased since pre-industrial times with an increase of about 70%
between 1970 and 2004 (IPCC, 2007). Man-made carbon dioxide which, is the most important
contributor to the enhanced greenhouse gases effect, comes mainly from the use of coal, fossil
, fuel/oil, and natural gas. It is also released by the destruction of forests and other natural sinks
and reservoirs that absorb carbon dioxide from the air. Depending on the temperatures of the
Ocean it assimilates and releases CO2.
The IPCC (2007) also reports that the atmospheric concentrations of CO 2 (397ppm) and CH4
(1774ppb) in year 2005 exceed by far the natural range over the last 650,000 years. Fossil fuel
use is the major contributor of global CO2, followed with land-use change. It has also been
reported that 1995-2006 are the warmest years in the history of instrumentation (since 1850) and
the global surface temperature rise is due to the greenhouse gases effect (IPCC, 2007). The major
effect of the increase of anthropogenic greenhouse gas emissions in the atmosphere is global
warming and thus changes in precipitation and the environment. The areas that are now dry-
humid, semiarid and arid will become semiarid, arid and desert respectively.
The Intergovernmental Panel on Climate Change (IPCC) is the leading international body for the
assessment of climate change was created in 1988. It was established by the United Nations
Environment Programme (UNEP) and the World Meteorological Organization (WMO) to
provide the world with a clear scientific view on the current state of knowledge in climate
change and its potential environmental and socio-economic impacts. The UN General Assembly
endorsed the action by WMO and UNEP in jointly establishing the IPCC.
BACK GROUND ON SEA LEVEL RISE DUE TO CLIMATE CHANGE
First Assessment Report
The First Assessment report under the IPCC business as usual emissions scenario, an average
rate of global mean sea level rise of about 6 cm per decade over the next century (with an
uncertainty range of 3 – 10 cm per decade), mainly due to thermal expansion of the oceans and
the melting of some land ice. The predicted rise is about 20 cm ... by 2030, and 65 cm by the end
of the next century ( IPCC, 1990).
Second Assessment Report
EXPECTED CLIMATE CHANGE
INTRODUCTION
The African coast line is about 26,000 km (16,000 mi) long. Major cities that lie along the
African coastline to name a few are: Cape Town, Durban, Maputo, Dar es Salaam, Kinshasa,
Alexandria, Casablanca, Abidjan, Accra and Lagos. Sea-level rise as an impact of human-
induced climate change has significant implications to low-lying coastal areas and beyond. The
coastal zone contains valuable ecosystems and typically has higher population densities than
inland areas (Small and Nicholls, 2003; McGranahan et al., 2007). Additionally, it generates
significant amounts of economic activity contributing to national wealth (Bijlsma et al., 1996;
Sachs et al., 2001). In physical terms the major direct impacts of sea-level rise include
inundation of low-lying areas, shoreline erosion, coastal wetland loss, saltwater intrusion, higher
water tables and higher extreme water levels leading to coastal flooding (Leatherman and
Nicholls, 1995). Human-induced pressures on the coastal zone (such as growing population,
water abstraction, and alteration of the hydrological regime including the damming of sediments)
will exacerbate projections the effects of sea-level rise (Nicholls et al., 2007). However, due to
uncertainties in future and a lack of systematic data, these factors cannot be fully considered in
this report. Hence, the main issue addressed in this report is sea-level rise and its effects on
coastal areas. Table 1 shows the population of major coastal African cities.
Table 1. African Coastal cities with their corresponding population (2017)
City Country City Population Urban population
Alexandria Egypt 3806300 4345800
Casablanca Morocco 3344300 3344300
Abidjan (Ivory Coast) 3310500 3972300
Kinshasa DRC 6301100 7527500
Cape Town South Africa 2686000 3086600
,Dar es Salaam Tanzania 2456100 2456100
Durban South Africa 2354900 2354900
Tripoli Libya 1890600 2271800
Algiers Algeria 1696000 3815900
Accra Ghana 1605400 2756100
Mogadishu Somalia 1183100 1183100
Maputo Mozambique 1088100 1639300
Port Harcourt Nigeria 1053900 1190600
Freetown Sierra Leone 1032100 1032100
Port Elizabeth South Africa 833900 1047600
Douala Cameroon 1239100 1449400
Conakry Guinea 1595800 1595800
Dakar Senegal 2384000 2384000
Anthropogenic greenhouse gases warming up has been considered to be the major potential
mechanism of climate change over the next few hundred years. A number of gases that occur
naturally in the atmosphere in small quantities are known as “greenhouse gases”. Water vapour
(H2O), carbon dioxide (CO2), ozone (O3), methane (CH4), and nitrous oxide (N2O) trap solar
energy in much the same way as do the glass panels of a greenhouse or a closed automobile
(IPCC, 1990). It has been established that the climate change in the next 100 years will be due to
anthropogenic activities (IPCC, 2001).
Human activities, however, are now raising the concentrations of these gases in the atmosphere
and thus increasing their ability to trap energy. The global greenhouse gas emissions due to
anthropogenic activities have increased since pre-industrial times with an increase of about 70%
between 1970 and 2004 (IPCC, 2007). Man-made carbon dioxide which, is the most important
contributor to the enhanced greenhouse gases effect, comes mainly from the use of coal, fossil
, fuel/oil, and natural gas. It is also released by the destruction of forests and other natural sinks
and reservoirs that absorb carbon dioxide from the air. Depending on the temperatures of the
Ocean it assimilates and releases CO2.
The IPCC (2007) also reports that the atmospheric concentrations of CO 2 (397ppm) and CH4
(1774ppb) in year 2005 exceed by far the natural range over the last 650,000 years. Fossil fuel
use is the major contributor of global CO2, followed with land-use change. It has also been
reported that 1995-2006 are the warmest years in the history of instrumentation (since 1850) and
the global surface temperature rise is due to the greenhouse gases effect (IPCC, 2007). The major
effect of the increase of anthropogenic greenhouse gas emissions in the atmosphere is global
warming and thus changes in precipitation and the environment. The areas that are now dry-
humid, semiarid and arid will become semiarid, arid and desert respectively.
The Intergovernmental Panel on Climate Change (IPCC) is the leading international body for the
assessment of climate change was created in 1988. It was established by the United Nations
Environment Programme (UNEP) and the World Meteorological Organization (WMO) to
provide the world with a clear scientific view on the current state of knowledge in climate
change and its potential environmental and socio-economic impacts. The UN General Assembly
endorsed the action by WMO and UNEP in jointly establishing the IPCC.
BACK GROUND ON SEA LEVEL RISE DUE TO CLIMATE CHANGE
First Assessment Report
The First Assessment report under the IPCC business as usual emissions scenario, an average
rate of global mean sea level rise of about 6 cm per decade over the next century (with an
uncertainty range of 3 – 10 cm per decade), mainly due to thermal expansion of the oceans and
the melting of some land ice. The predicted rise is about 20 cm ... by 2030, and 65 cm by the end
of the next century ( IPCC, 1990).
Second Assessment Report
