**1. Introduction**

Not only countries from Sub-Saharan Africa (SSA) are experiencing water security challenges, other developing countries in the world are also facing water security problems. Water security challenges may affect the environmental, economic and social stability and wellbeing in these countries particularly those in SSA regions. The seriousness of these circumstances highlights the need to examine the impact of climate change factors––rain and temp–– that may have water security and people movement in SSA. Water security in SSA has been an essential part of the SSA's attempt to achieve sustainable food security and the aim is to eradicate hunger and halve poverty. The chapter selects three Sub-Saharan African countries on the grounds of geographical location, population size and growth rates, people migration, climatic change conditions, current and projected water resources in terms of renewable fresh water resources (m3 /capita/yr), as well as economic stability and development.

Water is essential for the existence of life on the planet, it is the primary component of the ecosystem and is used for many purposes [1–3]. The three main purposes are agriculture, industry and domestic, water is also utilized in energy production, transport and recreation. Economic activities, agricultural development and environmental systems could only exist when there is water available to them [4–8]. Nelson Mandela said "*Among the many things that I learnt as president was the centrality of water in the social, political and economic affairs of the country, the continent and the world*" [9, 6, 10]. Lack of the necessary water infrastructure appears to be a major challenge faced in the developing countries, particularly those in SSA [11]. In SSA, water availability and accessibility processes are complicated and time consuming; for instance, in some SSA regions where hours are spent each day by household members to collect water for domestic consumption. It is estimated that a round trip takes an average of 36 min to collect drinking water [5]. The amount of fresh water per capita in the SSA has declined; it dropped about 30% since 1990 [11]. According to [12], 30% of world population lives in dry lands that have only 8% of the total renewable freshwater resources. Climate change is expected to exacerbate water security situation in these areas that are already under water stress. **Figure 1** presents world's environmental hotspots and migration.

is around 35,318.3 ft3

1700 m3

/yr or 1000 m<sup>3</sup>

**Figure 1.** Environmental hotspots and migration [13].

for Niger in **Figure 2** seems to incorrect.

the available fresh water per capita per annum is higher than 1000 m3

that Niger has been under water scarcity condition since 1962 and had 183 m<sup>3</sup>

/yr [7, 14, 15]. Further, a water stress situation exists when

/capita/yr [14–17]. On the other hand, water shortage is defined as the ratio of the total

The Effects of Climate Change on Rural-Urban Migration in Sub-Saharan Africa (SSA)—The…

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5

fresh water withdrawal to the available rainfall [18]. The condition of water scarcity (WSC) can also exist when the demand of fresh water (WD) exceeds the fresh water supply (WS) available in a certain period and/or place, that is, when water requirements of some sectors are not met. Water scarcity can also be expressed as a formula: WSC = WD ≥ WS; [13]. **Figure 2** presents water availability for some African countries in 1999 and 2025. In fact, the World Bank reported

internal freshwater resources per capita in 2014, therefore water availability condition shown

Despite that Sub-Saharan African region appears to have enough water resources all around the year [20], these waters are unevenly distributed between member states. There has been sufficient rainfall in Central Africa region due to the humid and semi-humid weather conditions, these favourable rainfall conditions resulted water resources abundance in this region. In contrast, there have been considerable rainfall fluctuations in dry and semi-dry regions that experience temperate and semi-temperate climates. The precipitation in these regions characterize high intensity but occurs within short periods of time; often producing floods and rainwater runoff washing fertile topsoil to downstream [21]. Moreover, Zambia, Angola and Mozambique experienced intense rainfalls in 2000 that caused subsequent floods. However, such heavy rainfalls seem not to have improved the water availability. In fact they have all experienced droughts over the past three decades [22]. The SSA rainfall fluctuation, frequency and amount are met by similar increases in levels of dryness in the region [23]. A period of

/capita/yr and less than

of renewable

To describe water scarcity, there have been several definitions that were in use in recent decades, while majority of these definitions did not receive an unreserved recommendation; however, there has been common view of the primary requirements of water scarcity definition. One of the main requirements of water scarcity definition is that it must suggest possible ways to conduct both quantitative and qualitative assessments. The World Water Development Report listed some of these definitions and defines water scarcity as "*The point at which the aggregate impact of all users impinges on the supply or quality of water under prevailing institutional arrangements to the extent that the demand by all sectors, including the environment, cannot be satisfied fully, a relative concept that can occur at any level of supply or demand. Scarcity may be a social construct (a product of affluence, expectations and customary behaviour) or the consequence of altered supply patterns stemming from climate change. Scarcity has various causes, most of which are capable of being remedied or alleviated*" [13–15].

Water scarcity is the situation where the available fresh water per capita is less than 1000 m<sup>3</sup> per annum––in other words, the minimum agreed amount of fresh water for human survival The Effects of Climate Change on Rural-Urban Migration in Sub-Saharan Africa (SSA)—The… http://dx.doi.org/10.5772/intechopen.72226 5

**Figure 1.** Environmental hotspots and migration [13].

**1. Introduction**

4 Applications in Water Systems Management and Modeling

(m3

Not only countries from Sub-Saharan Africa (SSA) are experiencing water security challenges, other developing countries in the world are also facing water security problems. Water security challenges may affect the environmental, economic and social stability and wellbeing in these countries particularly those in SSA regions. The seriousness of these circumstances highlights the need to examine the impact of climate change factors––rain and temp–– that may have water security and people movement in SSA. Water security in SSA has been an essential part of the SSA's attempt to achieve sustainable food security and the aim is to eradicate hunger and halve poverty. The chapter selects three Sub-Saharan African countries on the grounds of geographical location, population size and growth rates, people migration, climatic change conditions, current and projected water resources in terms of renewable fresh water resources

Water is essential for the existence of life on the planet, it is the primary component of the ecosystem and is used for many purposes [1–3]. The three main purposes are agriculture, industry and domestic, water is also utilized in energy production, transport and recreation. Economic activities, agricultural development and environmental systems could only exist when there is water available to them [4–8]. Nelson Mandela said "*Among the many things that I learnt as president was the centrality of water in the social, political and economic affairs of the country, the continent and the world*" [9, 6, 10]. Lack of the necessary water infrastructure appears to be a major challenge faced in the developing countries, particularly those in SSA [11]. In SSA, water availability and accessibility processes are complicated and time consuming; for instance, in some SSA regions where hours are spent each day by household members to collect water for domestic consumption. It is estimated that a round trip takes an average of 36 min to collect drinking water [5]. The amount of fresh water per capita in the SSA has declined; it dropped about 30% since 1990 [11]. According to [12], 30% of world population lives in dry lands that have only 8% of the total renewable freshwater resources. Climate change is expected to exacerbate water security situation in these areas that are already under

water stress. **Figure 1** presents world's environmental hotspots and migration.

*which are capable of being remedied or alleviated*" [13–15].

To describe water scarcity, there have been several definitions that were in use in recent decades, while majority of these definitions did not receive an unreserved recommendation; however, there has been common view of the primary requirements of water scarcity definition. One of the main requirements of water scarcity definition is that it must suggest possible ways to conduct both quantitative and qualitative assessments. The World Water Development Report listed some of these definitions and defines water scarcity as "*The point at which the aggregate impact of all users impinges on the supply or quality of water under prevailing institutional arrangements to the extent that the demand by all sectors, including the environment, cannot be satisfied fully, a relative concept that can occur at any level of supply or demand. Scarcity may be a social construct (a product of affluence, expectations and customary behaviour) or the consequence of altered supply patterns stemming from climate change. Scarcity has various causes, most of* 

Water scarcity is the situation where the available fresh water per capita is less than 1000 m<sup>3</sup> per annum––in other words, the minimum agreed amount of fresh water for human survival

/capita/yr), as well as economic stability and development.

is around 35,318.3 ft3 /yr or 1000 m<sup>3</sup> /yr [7, 14, 15]. Further, a water stress situation exists when the available fresh water per capita per annum is higher than 1000 m3 /capita/yr and less than 1700 m3 /capita/yr [14–17]. On the other hand, water shortage is defined as the ratio of the total fresh water withdrawal to the available rainfall [18]. The condition of water scarcity (WSC) can also exist when the demand of fresh water (WD) exceeds the fresh water supply (WS) available in a certain period and/or place, that is, when water requirements of some sectors are not met. Water scarcity can also be expressed as a formula: WSC = WD ≥ WS; [13]. **Figure 2** presents water availability for some African countries in 1999 and 2025. In fact, the World Bank reported that Niger has been under water scarcity condition since 1962 and had 183 m<sup>3</sup> of renewable internal freshwater resources per capita in 2014, therefore water availability condition shown for Niger in **Figure 2** seems to incorrect.

Despite that Sub-Saharan African region appears to have enough water resources all around the year [20], these waters are unevenly distributed between member states. There has been sufficient rainfall in Central Africa region due to the humid and semi-humid weather conditions, these favourable rainfall conditions resulted water resources abundance in this region. In contrast, there have been considerable rainfall fluctuations in dry and semi-dry regions that experience temperate and semi-temperate climates. The precipitation in these regions characterize high intensity but occurs within short periods of time; often producing floods and rainwater runoff washing fertile topsoil to downstream [21]. Moreover, Zambia, Angola and Mozambique experienced intense rainfalls in 2000 that caused subsequent floods. However, such heavy rainfalls seem not to have improved the water availability. In fact they have all experienced droughts over the past three decades [22]. The SSA rainfall fluctuation, frequency and amount are met by similar increases in levels of dryness in the region [23]. A period of

by other main rivers in SSA regions such as the Congo, Zambezi and Niger Rivers. In addition to that, SSA has Lake Victoria, which is the second largest lake in the world [29, 31, 32]. Approximately 53% of Africa is believed to be water abundant and about 61% of the total population live in this region which also holds about 95% of the total renewable water resources of the continent [31]. Nonetheless, it is predicted that by 2025 Africa's water abundance area may shrink to 35 and 24% of the population that will inhabit in water abundance areas that holds 78% of available renewable water resources. In contrast, the combined water scarcity and deficit areas is expected to increase from 47% of (2000) to 65% in 2025, holding only 22% of the total renewable water resources; so 76% of Africa's population will live in water scarcity

The Effects of Climate Change on Rural-Urban Migration in Sub-Saharan Africa (SSA)—The…

and the average annual rainfall of SSA is estimated to around 815 mm/yr. However, there have been considerable variations of rainfall amounts in SSA's sub regions; that may be due to climatic differences [34]. Compounding rainfall fluctuation will be the anticipated effects of climate change that will cause more challenges that are yet to be seen. For instance, this may include sudden and large increase in rainfall fluctuations and distribution in the SSA region, creating natural disasters such as floods and droughts have been noted [2, 6, 35, 36]. For instance, annual rainfalls in Sierra Leone, Liberia, Seychelles and Mauritius may reach 2000 mm/yr [34]. In contrast, parts of South Africa and eastern Namibia the annual rainfall is less than 100 mm/yr. Further rainfall in northern Niger may be as low as 10 mm/yr [34]. Hell et al. [37] reported that rainfall in the African is unevenly distributed and added that fewer people live regions that often receive higher rainfall compared to overpopulated regions that receive lower rainfall. According to Temesgen [38], in 2009 around 260 million people in SSA

Faurès and Santini [34] reported that production factors such as land and water resources may be abundant in SSA but the region continues to experience a falling GDP of 0.6% since 2004 [38]. Agriculture remains to be the main source of food to SSA's low socioeconomic communities; rainfed agriculture is anticipated to be the dominating food production system in SSA in foreseeable future. Number of people living under poverty level and undernourished worldwide has been falling in recent decades in general and in Asia in particular. In SSA, the number of people living under the poverty line has not decreased considerably compared to other world regions. Further, SSA has made limited progress in improving the lives of poor

Abundance 52.5 60.8 95.2 34.7 23.9 78.3 Scarcity 26.0 24.3 4.4 39.1 57.3 20.6 Deficit 21.5 14.9 0.4 26.2 18.8 1.1

**Area % Population % Water % Area % Population % Water %**

(41% of SSA's population) lived in dry areas that are vulnerable to drought.

**Countries with water 2000 2025**

Total African population 786 million 1428 million

**Table 1.** Water availability projections according to three different conditions in Africa 2000–2025.

Ashton [31].

[26, 32] that is equal to 18% of the world's land [33]

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7

and deficit areas in 2025 as shown in **Table 1**.

Sub-Saharan Africa has 24.24 million km<sup>2</sup>

**Figure 2.** Water availability for some African countries in 1999 and 2025 [19].

low rainfall means a period of scarcity of both feed and water, and an increase in distances to suitable grazing areas [24]; this study also notes that among small-scale farmers, rainfall is the most important climatic factor that is critical to their survival, particularly for crop growth and livestock herds. Geographically, SSA falls below the Sahara Desert and consists of the vast majority of African countries. The countries that fall in the Northern Africa region that are Egypt, Libya, Tunisia, Algeria and Morocco are not in SSA [25]. SSA has an estimated land area of 24.24 million km<sup>2</sup> [26].

In this chapter, authors critically review the water security and migration situation in SSA region by using a country by country analysis of three selected countries from SSA region. The main aim of this study is to examine water resources availability and accessibility and how rainfall and temperature variations and distributions have impacted water security and people urban migration in the region. The study attempts to identify pull and push factors that appear to affect the people movement from rural to urban areas in SSA. The selected SSA countries are Democratic Republic of Congo (DRC), Kenya and Niger. This study uses VAR and Granger causality methods to analyse rainfall and temperature and their impact on rural/urban migration.
