15 Impacts of Climate Change on Water Resources …
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scale atmospheric and global oceanic phenomena like El Niño and Southern Oscillation (ENSO) would pose further serious challenges to riparian countries which jointly
depend on hydropower as a renewable energy resource. The Akosombo and Kpong
reservoirs downstream produce 4,800 GWh/year of hydroenergy; Bui in mid-Volta
produces 980 GWh/year. Upstream in Burkina Faso, hydroenergy production is 65,
19 and 17 GWh/year at Bagre, Kompienga and Samandeni reservoirs, respectively
(Sonabel 2009; VRA 2009; Lemoalle and de Condappa 2009).
The basin is underdeveloped, and economies are based predominantly on agriculture and hydropower generation. The availability of water is subject to the climate, the
environment and the infrastructure available for water storage and use. The primary
source of water in the basin is rainfall modulated by general circulation, evaporation and transpiration from vegetation. Rainfall becomes a surface and groundwater
resource through hydrological processes. Temperature can cause water to be lost to
the atmosphere without having been used. Climate change, caused to a large extent
by anthropogenic activity, is impacting global climates and thus the availability of
water for human survival and socioeconomic activities, including agricultural development, hydropower generation and water supply for domestic and industrial use.
This literature review looks at the evolution of climate change and its impacts on water
resources in the basin in the past, and projects impacts in the future. Temperature
and rainfall projections for the basin developed by the IPCC and used in simulations
in the Regional Climate Models (RCMs) and Global Circulation Model (GCMs) are
discussed.
2 The Volta Basin
2.1 Physical and Geopolitical Settings
The Volta Basin is the ninth largest in West Africa. It lies between latitudes 5
o 30’N
and 14
o 30’N and longitudes 2
o 00’E and 5
o 30’W (UNEP-GEF Volta Project 2013).
It covers an area of about 400,000 km
2 and spreads over Benin, Burkina Faso, Cote
d’Ivoire, Ghana, Mali and Togo. Lemoalle and de Condappa (2009) noted that 85%
of the basin area is in Burkina Faso and Ghana. The Volta Basin is delimited at its
eastern and western borders by a series of hills and mountain ranges. At the eastern
border, there are the Akwapim ranges, Togo Mountains, Fazao Mountains and the
Atakora Mountains in Benin. The Kwahu Plateau and Banfora Plateau constitute the
western border. Ninety-five percent of the basin lies at an altitude below 400 m, with
an average elevation of 257 m. The basin slope index is 0.25 m/km.
335
scale atmospheric and global oceanic phenomena like El Niño and Southern Oscillation (ENSO) would pose further serious challenges to riparian countries which jointly
depend on hydropower as a renewable energy resource. The Akosombo and Kpong
reservoirs downstream produce 4,800 GWh/year of hydroenergy; Bui in mid-Volta
produces 980 GWh/year. Upstream in Burkina Faso, hydroenergy production is 65,
19 and 17 GWh/year at Bagre, Kompienga and Samandeni reservoirs, respectively
(Sonabel 2009; VRA 2009; Lemoalle and de Condappa 2009).
The basin is underdeveloped, and economies are based predominantly on agriculture and hydropower generation. The availability of water is subject to the climate, the
environment and the infrastructure available for water storage and use. The primary
source of water in the basin is rainfall modulated by general circulation, evaporation and transpiration from vegetation. Rainfall becomes a surface and groundwater
resource through hydrological processes. Temperature can cause water to be lost to
the atmosphere without having been used. Climate change, caused to a large extent
by anthropogenic activity, is impacting global climates and thus the availability of
water for human survival and socioeconomic activities, including agricultural development, hydropower generation and water supply for domestic and industrial use.
This literature review looks at the evolution of climate change and its impacts on water
resources in the basin in the past, and projects impacts in the future. Temperature
and rainfall projections for the basin developed by the IPCC and used in simulations
in the Regional Climate Models (RCMs) and Global Circulation Model (GCMs) are
discussed.
2 The Volta Basin
2.1 Physical and Geopolitical Settings
The Volta Basin is the ninth largest in West Africa. It lies between latitudes 5
o 30’N
and 14
o 30’N and longitudes 2
o 00’E and 5
o 30’W (UNEP-GEF Volta Project 2013).
It covers an area of about 400,000 km
2 and spreads over Benin, Burkina Faso, Cote
d’Ivoire, Ghana, Mali and Togo. Lemoalle and de Condappa (2009) noted that 85%
of the basin area is in Burkina Faso and Ghana. The Volta Basin is delimited at its
eastern and western borders by a series of hills and mountain ranges. At the eastern
border, there are the Akwapim ranges, Togo Mountains, Fazao Mountains and the
Atakora Mountains in Benin. The Kwahu Plateau and Banfora Plateau constitute the
western border. Ninety-five percent of the basin lies at an altitude below 400 m, with
an average elevation of 257 m. The basin slope index is 0.25 m/km.