A focus on Ethiopia
In the space of this blog, it would be impossible for me to effectively cover climate change and its impact on all of Africa's freshwater resources; the continent is huge and varies both physically and socially and therefore, climate change's impact will vary substantially between places. So, in order for me to gain a deeper understanding of how climate change, specifically changes in precipitation intensity and duration, will affect freshwater resources, namely groundwater and surface water supplies, I will purposely focus on Ethiopia for the remainder of this blog.
Firstly, why Ethiopia...?
Located in the Horn of Africa (Figure 1), Ethiopia is the second most populous country in Africa (after Nigeria), with a current population of over 105 million. The country is one of the poorest in the world, exhibiting a GDP per capita of only $1,900 and having almost a third of its population below the poverty line in 2014 (CIA, 2017). However, from government investment in infrastructure and continued progress in agricultural and service sectors, Ethiopia's economy grew between 8-11% for almost a decade before 2016 (CIA, 2017).
The country hopes to attain lower middle-class income status in less than ten years (World Bank, 2017), but the country faces multiple challenges that may hinder development challenges, including rapid population growth and a low starting base. Additionally, the country's lack of management and access to freshwater resources is regarded to deeply constrain its development, costing Ethiopia's economy one third of its growth potential (World Bank, 2006).
Water resources in Ethiopia
Ethiopia's water resources appear at first to be plentiful: total renewable surface water resources is approximated to be 122 billion cubic metres/year from 12 river basins and 22 lakes, whilst renewable groundwater resources are approximated to be 2.6 billion cubic meters. Per capita renewable freshwater resources is estimated to be 1,900 cubic meters, indicating an abundance of water (World Bank, 2006).
Unfortunately this isn't the case... Ethiopia exhibits high hydrological variability and unpredictability, with rainfall patterns varying both spatially and temporally. For instance, there are large spatial variations in rainfall across Ethiopia due to the different rainfall regimes: mono-modal rainfall pattern in the west; bi-modal rainfall pattern in the central and eastern areas; and southern areas exhibit another bi-modal rainfall pattern, but the wet seasons occurring slightly after the wet seasons in the central and eastern areas. Most of the country experiences just one single short rainy season.
Surface water resources also show this spatio-temporal variability, following the pattern of rainfall: basins that receive two rainfall seasons have two peak flows, and the basins receiving one wet season have only one peak flow (Kidanewold et al., 2014). Ethiopia generally exhibits usable groundwater resources, but due to heterogeneity over geology (that influences the productivity and transmission), the occurrence of groundwater resources is not uniform (Kidanewold et al., 2014)
Ethiopia has limited investment and management of water resources, resulting in issues over storage and supply for the drier seasons. Consequently, this high variability coupled with limited water resource management and storage capacity results in unpredictable drought and flooding (World Bank, 2006).
Climate change and its impact on water resources in Ethiopia
This rainfall variability, specifically amount, timing and intensity, is predicted to be a main climatic hazard for Ethiopia in the future; it is expected that drought and flooding will increase (Keller, 2009). These changes in extreme weather events will affect stream flow and resultant stores of water at local and regional levels (Akica, 2012).
What does this mean for Ethiopia?
This inter-annual and seasonal variability in rainfall is strongly related to agricultural output since most agriculture is rain-fed: between 1994 and 2003, production of cereals grown in the country show similar patterns to inter-annual variability in seasonal or annual rainfall amounts, with certain cereals (such as barley, sorghum and wheat) showing stronger correlations (Bewket, 2009). Therefore, farmers are highly vulnerable to rainfall variability, specifically increased drought and flooding, with implications for not only the economy (agriculture accounts for 37.2% of the country's GDP (CIA, 2017)) but also food security (Bewket, 2009).
Ethiopia provides an interesting case study: it's a country subject to unfavourable rainfall conditions for water availability (that are expected to be amplified under climate change), but similarly aims to achieve significant development within the next ten years. Its access to water resources are dependent on this.
Next time, I plan to delve deeper into this water security and development nexus, specifically examining climate change and urbanisation in Addis Ababa, Ethiopia's capital city.
Firstly, why Ethiopia...?
Located in the Horn of Africa (Figure 1), Ethiopia is the second most populous country in Africa (after Nigeria), with a current population of over 105 million. The country is one of the poorest in the world, exhibiting a GDP per capita of only $1,900 and having almost a third of its population below the poverty line in 2014 (CIA, 2017). However, from government investment in infrastructure and continued progress in agricultural and service sectors, Ethiopia's economy grew between 8-11% for almost a decade before 2016 (CIA, 2017).
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| Figure 1: Ethiopia and its location within Africa |
The country hopes to attain lower middle-class income status in less than ten years (World Bank, 2017), but the country faces multiple challenges that may hinder development challenges, including rapid population growth and a low starting base. Additionally, the country's lack of management and access to freshwater resources is regarded to deeply constrain its development, costing Ethiopia's economy one third of its growth potential (World Bank, 2006).
Water resources in Ethiopia
Ethiopia's water resources appear at first to be plentiful: total renewable surface water resources is approximated to be 122 billion cubic metres/year from 12 river basins and 22 lakes, whilst renewable groundwater resources are approximated to be 2.6 billion cubic meters. Per capita renewable freshwater resources is estimated to be 1,900 cubic meters, indicating an abundance of water (World Bank, 2006).
Unfortunately this isn't the case... Ethiopia exhibits high hydrological variability and unpredictability, with rainfall patterns varying both spatially and temporally. For instance, there are large spatial variations in rainfall across Ethiopia due to the different rainfall regimes: mono-modal rainfall pattern in the west; bi-modal rainfall pattern in the central and eastern areas; and southern areas exhibit another bi-modal rainfall pattern, but the wet seasons occurring slightly after the wet seasons in the central and eastern areas. Most of the country experiences just one single short rainy season.
Surface water resources also show this spatio-temporal variability, following the pattern of rainfall: basins that receive two rainfall seasons have two peak flows, and the basins receiving one wet season have only one peak flow (Kidanewold et al., 2014). Ethiopia generally exhibits usable groundwater resources, but due to heterogeneity over geology (that influences the productivity and transmission), the occurrence of groundwater resources is not uniform (Kidanewold et al., 2014)
Ethiopia has limited investment and management of water resources, resulting in issues over storage and supply for the drier seasons. Consequently, this high variability coupled with limited water resource management and storage capacity results in unpredictable drought and flooding (World Bank, 2006).
Climate change and its impact on water resources in Ethiopia
This rainfall variability, specifically amount, timing and intensity, is predicted to be a main climatic hazard for Ethiopia in the future; it is expected that drought and flooding will increase (Keller, 2009). These changes in extreme weather events will affect stream flow and resultant stores of water at local and regional levels (Akica, 2012).
What does this mean for Ethiopia?
This inter-annual and seasonal variability in rainfall is strongly related to agricultural output since most agriculture is rain-fed: between 1994 and 2003, production of cereals grown in the country show similar patterns to inter-annual variability in seasonal or annual rainfall amounts, with certain cereals (such as barley, sorghum and wheat) showing stronger correlations (Bewket, 2009). Therefore, farmers are highly vulnerable to rainfall variability, specifically increased drought and flooding, with implications for not only the economy (agriculture accounts for 37.2% of the country's GDP (CIA, 2017)) but also food security (Bewket, 2009).
Ethiopia provides an interesting case study: it's a country subject to unfavourable rainfall conditions for water availability (that are expected to be amplified under climate change), but similarly aims to achieve significant development within the next ten years. Its access to water resources are dependent on this.
Next time, I plan to delve deeper into this water security and development nexus, specifically examining climate change and urbanisation in Addis Ababa, Ethiopia's capital city.
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