A Systematic Review of International and Internal Climate-Induced Migration in Africa

Abstract

Academics and policymakers have been paying close attention to the impact of climate change on migration in recent years. This phenomenon piqued interest because the factors driving environmentally induced migration are complex and manifold. Noticeably, there has been considerable scholarship on climate change and migration in Africa. However, there has not been a concerted effort to periodically review the existing literature to systematically document the state of scholarship. Using a standardized systematic review procedures to analyze 22 peer-reviewed studies published between 2000 and 2022, we found that climate change impacts migration in many complex and multilayered forms. Beyond what has already been established in the literature on climate-related migration such as environmental effects on migration; migration as an adaptation strategy; and the influence of environmental and non-environmental factors on migration; we also found that (1) studies on climate-induced migration in Africa intensely focused on SSA, suggesting an uneven study of the region, (2) heavily affected people tend to be immobile, and (3) young people have high migration intentions due to harsh climate insecurities. These findings require urgent government and stakeholder attention. Specifically, there is a need for scholarship to interrogate the climate change–immobility nexus in order to design appropriate in situ or ex situ adaptation strategies to support lives and livelihoods.

1. Introduction

The impact of climate change on migration has received significant attention in academic and policy circles in recent years (Chirisa and Bandauko, 2015 [1]; Cottier et al., 2022 [2]; Hoffmann et al., 2020 [3]). Current estimates suggest that Sub-Saharan Africa (SSA) will contribute over 85 million (four percent of its total population) to climate-induced migrants due to droughts, floodings, high temperatures, and unpredictable rainfall patterns (Rigaud et al., 2018 [4]). Climate change threats are already manifesting in different African countries, negatively affecting lives and livelihoods that are natural resource dependent (e.g., agriculture, fisheries) (Azumah and Ahmed, 2023 [5]; Baada et al., 2021 [6]; Nguyen and Sean, 2021 [7]). Research on climate-related migration in Africa has expanded significantly over the years (see Azumah and Ahmed, 2023 [5]; Baada et al., 2021 [6]; Hermans and Garbe, 2019 [8]; Nawrotzki and DeWaard, 2018 [9]; Simatele and Simatele, 2015 [10]). As climate-related stressors such as heatwaves, droughts, and flooding continue to displace and affect different communities in Africa, some individuals and households migrate to other places as an adaption strategy. Therefore, migration can be both an effect of and adaption to climate change (Vinke et al., 2020 [11], 2022 [12]).

While some systematic reviews have been conducted on this subject, these studies have major weaknesses. A recent systematic review on climate-induced migration conducted by Kaczan and Orgill-Meyer (2020) [13] used quantitative approach using multivariate regression analysis. Moreover, the review excluded studies that rely on qualitative analysis, thereby missing important empirical insights on the experiences of people who migrate because of multiple climate-related disasters such as floods and droughts. This review also focused on studies from different developing countries. However, Africa is a unique continent with distinct climate-induced migration experiences that require careful attention. Similarly, Hoffmann et al.’s (2020) [3] use of meta-analysis on scientific studies published between 2006 and 2019 quantitatively analyzed the influence of different environmental factors on migration. While these studies are critical in associating climate change to migration, they tend to miss out on the perspectives of those who endure the complex consequences of climate-induced migration—i.e., the ‘climate migrant’. In Africa, Mensah and Ahadzie (2020) [14] conducted a systematic review on the causes, impacts, and coping strategies with floods in Ghana. Focusing on one country, the dynamics of climate-induced migration in other countries on the continent are obviously missed. Additionally, Ibrahim and Mensah’s (2022) [15] systematic review of climate-induced migration in SSA focused on studies that were published before 2000. Their review also excludes empirical studies/primary research on climate-induced migration; thus, it fails to capture the perspectives of climate migrants to understand their lived experiences. Geographically, the review focused on SSA, thereby excluding experiences from other African countries, such as those in North Africa (e.g., Morocco, Egypt). Relatedly, Borderon et al. (2018) [16] and Ghosh and Orchiston (2022) [17] have also conducted a systematic literature review on climate-induced migration in Africa. While these studies provide some interesting findings, there are some limitations worth mentioning. Borderon et al.’s (2018) [16] study for instance, used one source for their study, the Climig database: Migration, Climate Change and the Environment. Further, given that the authors examined climate migration-related discourse from 1986–2017, the state of scholarship from 2017–2022 might have undergone some changes, hence the uniqueness of the current study. Also, Ghosh and Orchiston’s (2022) [17] study is global with the aim of identifying research gaps in the scholarship; however, the global outlook of their study is likely to ignore the peculiarities of climate-induced migration issues in Africa.

Using standard systematic literature review protocols, this study discusses emerging themes from climate-induced migration from twenty-two peer-reviewed articles published between 2000 and 2022. The research questions guiding this study are: (a) what themes have emerged within the climate-induced migration literature in Africa? (b) How do these themes fit within the broader literature on the debate on climate-induced migration? This systematic review is timely and relevant for different reasons. First, this review provides a comprehensive overview of the existing literature on climate-induced migration in different African countries. The evidence synthesized here can help policymakers and development practitioners design relevant interventions to address climate-induced migration to improve livelihoods and other development-related outcomes. This will strengthen efforts towards achieving the Sustainable Development Goal (SDG) #13 on climate change. Currently, most African countries do not have proper agreements and policies for coping with climate change-induced migration, which may assist vulnerable people and populations looking for better living conditions (Fernández et al., 2019 [18]). Thus, this systematic review will amplify the complexity of climate-induced migration in Africa, highlighting issues that require specific policy attention. Second, climate-induced migration is a complex phenomenon, and this systematic review helps us clarify the scope and nature of the problem and highlight areas where further research is required. Third, in this systematic review, we synthesize findings from multiple studies to help identify patterns and trends that may not be apparent from individual studies.

2. Climate-Induced Migration: An Overview

Scholarly discussions on climate-induced migration have increased in recent years. Climate-induced migration is conceptualized as the movement of people or households from their communities due to changes in enviromnmental conditions, such as rising temperatures, rising sea levels, droughts, flooding, and other climate-related disasters (Azumah and Ahmed, 2023 [5]). Migration as a response to adverse climate stressors exists along an adaptation continuum, ranging from the reactive behaviour of displacement to the planned response and indulgence of seasonal migrants to diversify livelihoods in the face of extreme conditions (Kniveton et al., 2012 [19]). However, there is no consensus in the existing literature on the effects of climate change on migration due to the multidimensional and complex nature of this phenomenon (Cassin et al., 2022 [20]). While some of the existing literature investigates the drivers of climate migration (Baada et al., 2021 [6]; Ibrahim and Mensah, 2022 [15]; Lilleør and Van den Broeck, 2011 [21]; Nguyen and Sean, 2021 [7]), others focus exclusively on the effectiveness of migration as an adaption strategy, particularly in rural communities (Baada et al., 2021 [6]; Vinke et al., 2022 [12]). Within the rural context of climate change, natural factors such as climate stressors (e.g., floods, droughts) might push farmers to move out of rural areas to seek alternative livelihoods as a form of adaptation (Nguyen and Sean, 2021 [7]).

The existing research suggests that the drivers of climate-induced migration are sophisticated and multilayered, often intersecting with other factors to create complex scenarios (Ibrahim and Mensah, 2022 [15]). In several African countries, population movements are triggered by economic crises, conflict, violence, large-scale development projects, environmental change, and natural disasters (Ibrahim and Mensah, 2022 [15]). However, climate change increases the risks of these factors.

Droughts have been reported to be one of the main drivers of climate-induced migration in some African countries. Adaawen et al. (2019) [22], for instance, revealed that drought-related factors compel people in the Sahel, East, and Southern Africa to migrate to other places every year. This form of migration has been described as an adaptation strategy to deal with livelihood stresses (Azumah and Ahmed, 2023 [5]; Baada et al., 2021 [6]; Ibrahim and Mensah, 2022 [15]). Climate change-related stresses have been triggering the movement of pastoralists from Niger, Mali, and Northern Nigeria to neighbouring countries in search of water and grassland for their animals (Leal Filho et al., 2022 [23]). Climate-induced migration is likely to increase if people in Africa rely on agriculture for their livelihoods and local conditions continue to worsen. However, adaptation strategies adopted due to climate change stressors might have negative consequences (Guodaar et al., 2020 [24]). A study with climate migrants from Bourasso village, Burkina Faso, reported that some populations were likely to become trapped in the future due to worsening conditions, demonstrating that migration can be an ineffective strategy to respond to climate shocks (Vinke et al., 2022 [12]). They noted that multiple factors, such as structures of exploitation, adverse effects on health, and pressures on households who stayed behind impeded migration effectiveness (Vinke et al., 2022 [12]).

Some scholars argue that drought-induced mobility might result in competition and stress in resource-scarce areas, potentially triggering conflicts. For instance, drought-related farmer–herder conflicts and water tensions have become common and widespread in the Sahel and East Africa (Benjaminsen et al., 2009 [25]; Cabot, 2017 [26]). Similarly, Baada et al. (2021) [6] discovered that declining environmental resources in the Brong-Ahafo Region, Ghana have heightened competition between migrants and non-migrants for the few available resources, especially fertile lands. This sparked conflicts between the two groups and exposed migrants to economic exploitation by landlords who rent land to them at exorbitant prices, compared to non-migrant farmers. The impacts of climate change are also not evenly borne; they burden individuals and households differently due to varying socio-economic status. The poorest are especially vulnerable to the economic and environmental stresses of climate change. Yet, these vulnerable populations have limited adaptive capacities due to their already marginalised status and policy neglect (Baada et al., 2021 [6]). Moreover, the drivers of migration differ for women and men and climate change may shape the consequences of migration differently for men and women, boys, and girls (Vinke et al., 2022 [12]).

3. Method

This study aims to systematically synthesize the emerging themes from existing studies on climate-induced migration in Africa by summarizing and evaluating related studies to ascertain the state of the scholarship on this important subject matter. Though climate-induced migration is hotly debated among scholars and rapidly expanding in Africa, there is the need to continue to systematically survey the state of scholarship. As a result, this study employs a methodical review approach to investigate the “breadth and depth of the existing body of work” (Xiao and Watson, 2019 [27], p. 93) to identify recurring themes and gaps that need urgent investigation.

To carry out this study, the authors identified and screened the related literature using a modified version of Xiao and Watson’s (2019) [27] three stages of systematic literature review: (1) planning the review (identifying the problem and developing a review method), (2) conducting the review (search, screen, assess quality, extract data, evaluate and synthesize data), and (3) reporting the review (results). For the literature search, keywords were modified taking into consideration the exclusion criteria. The vast body of studies retrieved from the search on climate-induced migration in Africa were thoroughly screened for relevant articles to ensure the validity, reliability, and repeatability of the review process (Mengist et al., 2020 [28]; Xiao and Watson, 2019 [27]). Overall, we have conducted the review following these four steps—article search, selection, review, and analysis.

This study applied a list of inclusion and exclusion criteria in the literature selection process. The final articles selected for the review followed these five criteria: (1) The study must be conducted in Africa. Thus, studies that did not focus on Africa were eliminated from the list of articles. (2) The articles must focus on both international and internal migration induced by climate change activities (as conceptualized by the study). This suggests that studies that focus on how climate change activities have resulted in the migration of people within Africa or outside Africa were included in the study. Hence, the movement within Africa (internal) could be local or regional (e.g., between Uganda and Ethiopia) and outside Africa (international) could be to other continents (e.g., Asia, North America, or Europe). (3) The articles must report primary data from existing data sources. Primary data in this context implies data collected by researchers instead of data collected by other researchers or research organizations. (4) The articles must be published in peer-reviewed journals and must be written in the English language. This means that all grey literature is excluded from this study. (5) The articles must be published between 2000 and 2022. This timeline (2000–2022) was considered because climate change-related issues became topical in the 2000s, following the adoption of the Millennium Development Goals (MDGs).

This systematic review searched five databases: Science Direct, Google Scholar, Scopus, JSTOR, and Web of Science for relevant articles. These data observatories were considered for the search due to their online academic presence and the ability to crosscheck references and bibliographies easily. The identified databases aided the search for keywords derived from the research questions. The official search used Boolean operators (i.e., OR, AND, or NOT). Moreover, synonyms and truncated keywords and phrases were used to increase the search results. The search terms included: climate chang[e]*, environmental stress[ors]*, displacement, climate crises, climate emergency (drought, fire, flood, heat wave, sea level rise), AND/OR international migration and internal migration, AND/OR migrants, refugees, environmental migrants, AND/OR Africa. Search terms were jointly or separately run using the search criteria.

From the preliminary searches, a total of 891 articles, including 72 articles from a Google search were found. The articles were uploaded to Zotero for preface title and abstract scanning. In Zotero, duplicates and unrelated articles to the study objectives were omitted, reducing the total index of articles retrieved from 891 to 306. A reference list for the 306 potential articles was exported to Covidence for further review. Three reviewers were assigned title and abstract screening in Covidence which reduced the articles to 87. The title and abstract screening process was followed by a full-text reading by four reviewers to identify the study objectives. The full-text reading reduced the working list to 22. The 22 articles were included in this systematic literature review on climate-induced migration in Africa.

4. Data Synthesis

Using Covidence, a PRISMA checklist assessment was completed for the study (see Supplementary Materials). Figure 1 gives an overview of the data collection, organization, and evaluation process of articles identified, screened, accepted, and included for the final review. The flowchart provides insight into the number of articles retrieved and screened, duplicates removed, reasons for article exclusion, articles considered for full-text reading, and the final number of articles used for the review.

5. Results

5.1. Study Context

This study included twenty-two primary research conducted in Africa. The study context included countries such as Morocco, Nigeria, Cameroon, Congo-Brazzaville, Ethiopia, Burundi, Ghana, Senegal, Kenya, Somali, Burkina Faso, and Côte d’Ivoire (

Table 1. Summaries of reviewed studies.

No.	Author(s) and Title	Study Context	Thematic Area(s)	Methodological Approach	Key Findings
1.	Arnall, A. (2014) [29]. A climate of control: flooding, displacement and planned resettlement in the Lower Zambezi River valley, Mozambique	Mozambique	Climate change adaptation measure	A total of 19 semi-structured interviews with key informants, including academics, donors, and NGOs. A total of 65 semi-structured individual and focus group discussions with farmers and leaders of community-based organizations. The author also used secondary data.	1. Most participants believed that floods in the lower Zambezi Valley are a threat to lives and livelihoods. 2. Resettlement initiatives are affected by several factors. 3. Government interventions for climate resilience do not directly benefit local populations.
2.	Abu, M., Codjoe, S. N. A., and Sward, J. (2014) [30]. Climate change and internal migration intentions in the forest-savannah transition zone of Ghana.	Ghana	Climate change and internal migration	Household survey of 200 households in two communities. Data was analyzed using quantitative techniques.	1. Areas with perceived environmental stressors were not a primary predictor of migratory intentions. 2. The decision to migrate depends on a multidimensional factor 3. Household heads are more likely to nurture migration intentions.
3.	Nagabhatla, N., Cassidy-Neumiller, M., Francine, N. N., and Maatta, N. (2021) [31]. Water, conflicts and migration and the role of regional diplomacy: Lake Chad, Congo Basin, and the Mbororo pastoralist.	Democratic Republic of Congo (DRC)	Environmental and non-environmental influence on migration	The survey was conducted in the DRC. Questionnaires and focus group discussions with stakeholder was conducted. The study also uses geostatistical methods and remote sensing to verify changes over time.	1. The intersection of socio-economic and political stressors contribute to forced migration. 2. Surface water level reduction in the Lake Chad Basin has contributed to unproductive agriculture yield resulting in displacement, change in profession, and migration.
4.	Sanfo, S., Fonta, W. M., Diasso, U. J., Nikiéma, M. P., Lamers, J. P. A., and Tondoh, J. E. (2017) [32]. Climate- and Environment-Induced Intervillage Migration in Southwestern Burkina Faso, West Africa.	Burkina Faso	Environmental factors influencing migration	Data was collected in the southwestern region of Burkina Faso. The study was conducted in 12 villages with functioning meteorological stations. The authors used both in-depth interviews and focus group discussions covering a total of 158 households.	1. farmers’ perceptions of climate change are directly linked to climatic impacts on their livelihoods. 2. Farmers did not link climatic changes directly to migration. 3. Farmers identified forest and soil conditions as primary drivers of migration. 4. Also, farmers identified non-environmental factors of migration.
5.	Lietaer, S., and Durand-Delacre, D. (2021) [33]. Situating “migration as adaptation” discourse and appraising its relevance to Senegal’s development sector.	Senegal	Migration as an adaptation strategy	A total of 90 qualitative interviews were conducted with Senegalese policymakers, politicians, and civil servants.	1. Participants acknowledge that climate conditions did not solely influence migration. 2. The authors also found that the activities of international donors shape the direction and narrative of irregular migration and displacement in Africa.
6.	Groth, J., Ide, T., Sakdapolrak, P., Kassa, E., and Hermans, K. (2020) [34]. Deciphering interwoven drivers of environment-related migration—A multisite case study from the Ethiopian highlands	Ethiopia	Environmental factors influencing migration	A total of 18 focus group sessions were conducted in four districts; 42 semi-structured interviews were conducted with key informants and 20 interviews with returnees.	1. Land degradation and precipitation in northern Ethiopia negatively affect agriculture which can lead to migration. 2. Young participants expressed a stronger desire to live and work elsewhere due to harsh environmental conditions on agricultural activities. 3. Individual factors are not strong predictors of migration.
7.	Kolmannskog, V. (2010) [35]. Climate Change, Human Mobility, and Protection: Initial Evidence from Africa.	Somalia and Burundi	Environmental and non-environmental influence on migration	A total of 49 semi-structured interviews were conducted with experts and affected people.	1. Climate stressors such as drought are recurrent in Somalia, affecting people’s livelihoods. 2. Most Somali pastoralists always move to greener forest belts during periods of droughts. 3. Poor pastoral households with no means of mobility are forced to stay in areas with less rainfall. 4. Lack of government measures to regulate warring activities and misuse/overuse of natural resources has affected the environment.
8.	Groth, J., Hermans, K., Wiederkehr, C., Kassa, E., and Thober, J. (2021) [36]. Investigating environment-related migration processes in Ethiopia—A participatory Bayesian network.	Ethiopia	Environmental factors influencing migration	A total of 42 semi-structured household interviews, 18 focus group discussions, five expert interviews, and 20 migrant interviews in six districts.	1. Agricultural activities directly influence migration since it is a livelihood activity. 2. Contrary, insufficient agricultural yield can impact a household’s economic capital, potentially causing migration. 3. In instances where agricultural and non-agricultural activities reap positive returns migration reduces.
9.	Veronis, L., and McLeman, R. (2014) [37]. Environmental influences on African migration to Canada: focus group findings from Ottawa-Gatineau.	Djibouti, Somalia, Benin, Burkina Faso, Burundi, Cameroon, Congo-Brazzaville, Cote d’Ivoire, Democratic Republic of the Congo (DRC), Guinea, Rwanda, and Togo	Environmental factors influencing migration	Seven focus groups consisting of 47 migrants (24 men and 23 women) from the Horn of Africa were conducted for the study.	1. Participants believe that environmental factors trigger internal migration; however, none cited environmental stressors as immediate factors for their migration to Canada. 2. Most participants agreed environmental pressures contributed to the socio-economic factors that influenced their migration to Canada.
10.	Tafere, M. (2018) [38]. Forced displacements and the environment: Its place in national and international climate agenda.	Ethiopia, Kenya, Rwanda, Sudan, and Uganda	Environmental factors causing displacement	The study combined the following methods: (i) meta-analysis, (ii) rapid environmental assessment (REA), (iii) two focus group discussions, (iv) the Delphi approach to determine priorities among major environmental threats.	1. The study found that most displaced persons are located in climate change hot spots. 2. The initial phase of refugee settlement may expose victims to severe environmental impacts when proper planning is not done. 3. Loopholes in refugee protection laws encourage deforestation. 4. Camps are operated for decades without environmental impact assessment.
11.	Suckall, N., Fraser, E., Forster, P., and Mkwambisi, D. (2015) [39]. Using a migration systems approach to understand the link between climate change and urbanisation in Malawi	Malawi	Climate change-rural-urbanization nexus	This quantitative study used in-depth interviews and focus group discussions to collect data on migration intentions.	1. Climate change endangered both human and financial capital. 2. Environmental stressors decrease agricultural productivity which is a major source of income for people. 3. Access to information about urban opportunities is an important determinant of migrants.
12.	Marchiori, L., Maystadt, J.-F., and Schumacher, I. (2012) [40]. The impact of weather anomalies on migration in Sub-Saharan Africa.	Sub-Saharan Africa.	Environmental factors influencing migration	This paper used a cross-country panel dataset to examine how weather anomalies increased internal and international migration between 1960 and 2000.	1. Weather irregularities facilitate migration in agriculturally dependent countries. 2. Climate anomalies directly affect wages. 3. Climate anomalies intensify urbanization processes in countries dependent on agriculture.
13.	Simatele, D., and Simatele, M. (2015) [10]. Migration as an adaptive strategy to climate variability: a study of the Tonga-speaking people of Southern Zambia.	Zambia	Migration as an adaptation strategy	This study used a participatory research methodology with 30 households conducting focus group discussions and in-depth interviews.	1. The findings noted that extreme weather conditions significantly impacted participants’ involvement in agriculture. 2. Drought affected agriculture production and economic resources, contributing to migration. 3. Migration enablers such as social networks also facilitated participants’ movement.
14.	Codjoe, S., Nyamedor, F. H., Sward, J., and Dovie, D. B. (2017) [41]. Environmental hazard and migration intentions in a coastal area in Ghana: a case of sea flooding.	Ghana	Environmental factors influencing migration intention	This paper used mixed methods: a household survey of 350 and 12 focus group discussions.	1. Participants’ communities of residence and socio-economic capital are significant predictors of migration because of sea flooding. 2. Also, households with low economic resources and those without social capital have the highest migration index. 3. Finally, farmers are less likely to migrate, unlike skilled manual workers.
15.	Suckall, N., Fraser, E., and Forster, P. (2017) [42]. Reduced migration under climate change: evidence from Malawi using an aspirations and capabilities framework.	Malawi	Reduced migration/immobility and climate change	This article used a mixed method approach: 225 surveys, 75 interviews, and 93 focus group discussions.	1. Quantitative and qualitative data showed that most residents did not want to migrate. 2. However, the younger non-migrant cohort expressed the desire to migrate to experience city life. 3. Also, climatic conditions are likely to reduce socio-economic resources instigating migration, yet from the qualitative data, potential migrants possess high capital resources.
16.	Call, M., and Gray, C. (2020) [43]. Climate anomalies, land degradation, and rural out-migration in Uganda.	Uganda	Environment factors influencing migration	This quantitative study used panel data from 850 Ugandan households with environmental data on soils, forests, and climate conditions.	1. The result reveals that climate stressors, rather than land degradation, are the primary initiators of migration in Uganda.
17.	Akinbami, C., A., O. (2021) [44]. Migration and Climate Change Impacts on Rural Entrepreneurs in Nigeria: A Gender Perspective.	Nigeria	climate change as a driver of migration/migration as an adaptation to climate change	A qualitative method of in-depth interviews and focus group discussions was used to solicit responses from respondents in selected rural areas in Nigeria under four different vegetation zones.	1. The study reports differences in gender reactions to migration. 2. The study also discovered that climate change is a primary driver of migration as it affects livelihood activities differently in the various vegetation zones.
18.	Bayar, M., and Aral, M. M. (2019) [45]. An Analysis of Large-Scale Forced Migration in Africa.	Africa	Non-environmental factors causing migration	This study conducts a quantitative analysis of 48 African countries from 2011–2017, to investigate the impact of forced migration.	1. The findings indicate that violent conflicts, political unrest, and poverty are the primary causes of migration in Africa. 2. However, climate-induced migration indirectly affects migration while foreign aid fails to alleviate migration challenges.
19.	Ng’ang’a, S. K., Bulte, E. H., Giller, K. E., McIntire, J. M., and Rufino, M. C. (2016) [46]. Migration and Self-Protection Against Climate Change: A Case Study of Samburu County, Kenya.	Kenya	Complementarity of migration and adaptation to climate shocks	The authors collected household data between February and May 2012, interviewing 500 households randomly from five locations; out of the 500 households, 139 of the households were ‘‘migrant households”.	1. remittances are an important mechanism linking migration to livelihood activities in Kenya. 2. When faced with climatic anomalies, households adopt more rigorous measures such as purchasing drought-tolerant livestock.
20.	Vinke, K., Rottmann, S., Gornott, C., Zabre, P., Nayna Schwerdtle, P., and Sauerborn, R. (2022) [12]. Is migration an effective adaptation to climate-related agricultural distress in sub-Saharan Africa?	Ivory Coast, Mali, Burkina Faso	Migration as an adaptation strategy	Two sets of interviews were carried out—one directed at migrants and the other directed at the migrant-sending community. A total of 52 semi-structured qualitative interviews were conducted.	1. The study found that while men migrated in the off-season, women stayed behind to take care of other activities. 2. Both male and female migrants see migration to have adverse socio-economic and health effects. However, the lack of options due to deteriorating environmental conditions forces the men to migrate.
21.	Van Praag, L. (2021) [47]. Can I move or can I stay? Applying a life course perspective on immobility when facing gradual environmental changes in Morocco.	Morocco	Immobility in the context of climate change	The study uses 48 in-depth qualitative interviews conducted in Morocco between March and May 2018.	1. From the findings, few respondents saw no urgent need to migrate in the light of slow-onset environmental stressors. 2. Instead, migration desires were related to societal changes and employment prospects. 3. Contrary, the older participants did not consider migrating since they were settled and had stronger economic and social capital.
22	Baada, J., N., Baruah, B., and Luginaah, I. (2021) [6]. Looming crisis-changing climatic conditions in Ghana’s breadbasket: the experiences of agrarian migrants.	Ghana	Environmental factors influencing migration	The authors conducted 30 in-depth interviews and five focused group discussions between September and December 2016.	1. The findings revealed that changes in agricultural activities instigated migration intentions as agricultural returns are less. 2. Climate change impacts are unevenly distributed among rural agrarian regions since most migrant farmers have limited access to other sustainable farming methods.

). As part of the result, one (1) study reported on climate change adaptation measures in Mozambique. Three (3) other articles identified the themes of climate change and internal migration, environmental factors influencing migration, and migration intention. Additionally, one (1) other study examined the environmental and non-environmental influence on migration in the Democratic Republic of Congo (DRC). One (1) study in Burkina Faso reviewed environmental factors influencing migration. Another one (1) article on Senegal discussed migration as an adaptation strategy. Two (2) articles on Ethiopia focused on environmental factors influencing migration. Two (2) other articles on Malawi examined the climate change–rural–urbanization nexus and climate change’s impact on migration and mobility. One (1) paper on Zambia and another one (1) on Uganda explored migration as an adaptation strategy and the environmental factors influencing migration, respectively. Also, one (1) study on Nigeria discussed climate change as a driver of migration and migration as an adaptative strategy to climate change, while another paper (1) on Kenya examined migration situations and adaptation to climate shocks. In Morocco, one (1) article examined immobility in the context of climate change. Other articles jointly examined several contexts in Africa on the subject. There was one (1) on Somali and Burundi which examined environmental and non-environmental influences on migration. Another one (1) on Djibouti, Somalia, Benin, Burkina Faso, Burundi, Cameroon, Congo-Brazzaville, Cote d’Ivoire, Democratic Republic of the Congo (DRC), Guinea, Rwanda, and Togo looked at environmental factors influencing migration. While one (1) on Ethiopia, Kenya, Rwanda, Sudan, and Uganda investigated environmental factors causing displacement. A study (1) on Sub-Saharan Africa discusses environmental factors influencing migration, whereas one (1) study on 48 African countries examined non-environmental factors causing migration. Finally, one article (1) on Ivory Coast, Mali, and Burkina Faso discussed migration as an adaptation strategy. Unexpectedly, there was only one study that exclusively focused on North Africa. However, studies on climate-induced migration in Africa mostly focused on the SSA, suggesting an uneven study of the region.

5.2. Emerging Issues in the Reviewed Studies

The emerging themes from this systematic review are discussed in five clusters: environmental factors influencing migration, migration as an adaptation strategy, environmental and non-environmental forces influencing migration, climate change and internal migration, and climate change and immobility.

5.3. Environmental Factors Influencing Migration

The top issue in the reviewed studies is environmental factors driving migration. According to these studies, various environmental forces, including drought, strong winds, and high temperatures, interact to drive migration. Out of the twenty-two reviewed studies, ten studies investigate the role of environmental factors in migration decision-making (see Akinbami, 2021 [44]; Bada et al., 2021; Groth et al., 2021 [36]; Call and Gray, 2020 [43]; Groth et al., 2020 [34]; Tafere, 2018 [38]; Codjoe, 2017 [41]; Sanfo et al., 2017 [32]; Veronis and McLeman, 2014 [37]; Marchiori, Maystadt, Schumacher, 2012 [40]).

The impact of environmental shocks and stressors on people’s migration decisions has been well documented. Evidence from Burkina Faso suggests that key environmental changes such as drought, less rainfall, high temperatures, and dry spells result in resource scarcity, which drives migration and displacement (Sanfo et al., 2017 [32]). Soil infertility, deforestation, and land degradation are explicitly identified as key environmental forces driving migration (Sanfo et al., 2017 [32]). Similar evidence of environmentally induced migration was found in other geographical contexts, such as Northern Ethiopia (Groth et al., 2021 [36]; Groth et al., 2020 [34]), Ghana (Codjoe, 2017 [41]), and Uganda (Call and Gray, 2020 [43]). In Nigerian, it is evident that climate change is a major driver of migration, affecting livelihood practices differently and negatively impacting the entrepreneurial development of rural areas (Akinbami, 2021 [44]). Similarly, using a qualitative approach to explore migrant farmers’ premigration expectations due to climate change and postmigration experience, Baada et al. (2021) [6] demonstrate that among the already vulnerable rural agrarian populations who have escaped worsening environmental circumstances in the Upper-West Region (UWR), Ghana, their livelihoods are more susceptible to climate change, as poor climatic conditions play the dual role of a push factor in sending context and a major challenge at destination area. This presupposes that these migrants are not better off in their destination context. Evidence suggests that climate anomalies, rather than land degradation are the primary contributors to environmentally induced migration among Ugandan agricultural households, with heat stress being the most pressing environmental stressor (Call and Gray, 2020 [43]). This suggests that rising temperature is the most threatening component of environmental change to rural Ugandans (Call and Gray, 2020 [43]).

Other studies have focused on multiple countries and deployed several research approaches to examine environmental factors driving migration. Tafere (2018) [38], for instance, employs meta-analysis, rapid environmental assessment, focus group discussions, the Delphi approach, and spatial analysis to examine forced displacement due to environmental changes. The author discovers that there are common issues of environmental factors fueling migration in the five case study countries in East Africa (Ethiopia, Kenya, Rwanda, Sudan, and Uganda). Indeed, Tafere (2018) [38] discovers that environmental damage in the five countries causes refugee inflows and/or displacement. Similarly, using cross-country panel data to investigate how weather anomalies impact migration in SSA, Marchiori et al. (2012) [40] demonstrate the influence of weather irregularities on increased internal and international migration, where temperature and rainfall anomalies resulted in a total net dislocation of five million people between 1960–2000.

5.4. Migration as an Adaptation Strategy

The role of migration as a climate change adaptation strategy has received considerable attention from the international policy community and national governments globally. It is, therefore, unsurprising that one of the emerging themes from this systematic review centered on migration as an adaptation strategy. Among the five articles that address this theme (Lietaer and Durand-Delacre, 2021 [33]; Vinke et al., 2021 [11]; Karanja Ng’ang’a et al., 2016 [46]; Simatele and Simatele, 2015 [10]; Arnall, 2014 [29]), it is evident that interest in migration as a climate change adaptation strategy is growing. The growing interest is because individuals, households, and communities frequently regard migration as a form of climate change adaptation to mitigate the risks associated with climatic shocks and events (Vinke et al., 2021 [11]).

Evidence suggests that some national governments develop planned resettlement schemes as a climate change adaptation measure in the context of climate change. This is the case in Mozambique, where flooding has forced farmers along the Lower Zambezi River valley to relocate (Arnall, 2014 [29]). Furthermore, the author observes that a political perspective is required to better understand the causes and consequences of flooding, displacement, and resettlement because the over-reliance on weather anomaly debates that frequently dominates policy discourses only serves to divert attention from political interests (Arnall, 2014 [29]). From the viewpoint of Senegalese policymakers, diaspora institutions and stakeholders who play a critical role in the migration–development nexus, Lietaer and Durand-Delacre (2021) [33] reveal that notwithstanding the critical role of the environment as a driver of migration, other factors, such as social, cultural, and economic variables are equally important. Similar evidence has been found in other contexts in the reviewed studies, such as Zambia (see Simatele and Simatele, 2015 [10]). Particularly, evidence suggests that frequent and severe drought events, intense heat, occasional flooding or heavy rainfall, and cold episodes associated with frost are the top-most weather events that impede farming activities (Simatele and Simatele, 2015 [10]). The results of this study suggest that the climate change–migration nexus is complex.

The fact that migration decision is influenced by a combination of factors, such as events associated with extreme weather conditions, difficulties in accessing natural resources, conflicts over resources, repeated episodes of loss of household incomes, poverty, and loss of livestock resonate with the literature that climatic shocks alone cannot account for people’s migration flows. In a related study that seeks to explore the extent to which climate-induced migration of a household member is likely to promote the adoption of agricultural innovations in protecting against shocks, Karanja Ng’ang’a et al. (2016 [46], p. 55) discover that households “who have at least one member who has migrated are able to overcome barriers to employ high-cost agricultural innovations–through using remittances received—thus enhancing their self-protection against climate change-related shocks”. This finding resonates with the neo-economic of labour migration (NELM) theory assumption that a household member migration is for risk diversification and income maximization.

5.5. Environmental and Non-Environmental Forces Influencing Migration

From the analysis of the reviewed studies and by corroborating other works in different geographic contexts, it is evident that several factors intersect to define the migration trajectory of people. This evidence is found in three reviewed studies (see Nagabhatla et al., 2021 [31]; Bayar and Aral, 2019 [45]; Kolmannskog, 2010 [35]).

In investigating the dynamics between conflicts, land and water systems, social, political, and economic shocks among pastoralists in the Congo Basin and the Mborobo, Nagabhatla et al. (2021) [31] discover that forced migration and Internally Displaced Persons (IDPs) are caused by the interplay of conflicts, resource scarcity, and other political, social, and economic stressors. Moreso, the reduction in surface water caused by a multiplicity of hydrological factors, rising temperatures, social, and regulatory factors have led to loss of agriculture production and small-scale fishing resulting in displacement (Nagabhatla et al., 2021 [31]). Similarly, evidence suggests that several variables intersect to drive migration in Somalia and Burundi. Kolmannskog (2010) [35], for example, notes that there are links between conflict, disasters, and human mobility, with most Somali pastoralists always moving due to droughts caused by climate change. In a related study that investigates factors driving forced migration in 48 African countries between 2011 to 2017, findings reveal that while poverty, lack of democratic institutions, and interstate conflicts are the primary causes of forced migration, climate change has an indirect impact on large-scale forced migration (Bayar and Aral, 2019 [45]).

5.6. Climate Change and Immobility

The reviewed articles also investigate the climate change–immobility nexus. While mobility is expected to be the first choice for those affected by climatic events, some choose to stay put for a variety of reasons. Three reviewed articles specifically examine this connection (Van Praag, 2021 [47]; Suckall, et al., 2017 [42]; Suckall, et al., 2015 [39]). In a study that investigates the extent to which climate stresses and shocks are likely to influence the migration decision-making process in Malawi, evidence indicates that climate change is more probable to hinder migration than accelerate mobility because climatic conditions are more likely to erode financial, social, and human capital—and thereby diminishing migration ability (Suckall et al., 2017 [42]). Applying a life course perspective to immobility in the context of gradual environmental change in Morocco, Van Praag (2021) [47] discovers that while none of the research participants mention the urgent desire to move, older respondents do not deem migration as an option due to factors such as family and social ties and the lack of resources. Similar immobility or reduced mobility results are documented in the reviewed studies (see Suckall et al., 2015 [39]), where they conclude that climate change is expected to reduce rural–urban migration in Malawi.

5.7. Climate Change and Internal Migration

One of the reviewed studies focuses explicitly on the relationship between climate change and internal migration intentions (see Codjoe, 2014 [30]). This theme supports empirical research from different contexts that, in the midst of climatic shocks and events, affected populations are more likely to move internally than internationally. In Ghana, Codjoe et al. (2014) [30] discover that “socio-demographic factors such as age, household size and current migration status are significant predictors of migration intentions, with younger household heads, heads of migrant households and heads of smaller households being relatively more likely to have migration intentions than other household heads” (p. 341). This suggests that migration drivers are complex and manifold.

6. Discussion

The goal of this paper was to systematically review key issues that have emerged from the climate change–migration nexus in Africa. We employed standard systematic literature review protocols guided by the following questions: (a) What themes have emerged from the scholarship on climate change-induced migration in Africa? (b) How do these themes fit within the larger literature on the debate on climate change and migration? This study identifies five main themes from the scholarship on climate change and migration in Africa: (a) environmental factors influencing migration, (b) migration as an adaptation strategy, (c) environmental and non-environmental forces influencing migration, (d) climate change and immobility, and (e) climate change and internal migration.

One of the most striking themes that emerged from the reviewed studies is the role of environmental factors in driving migration. These environmental factors include slow and fast-onset climatic events and shocks caused by climate change. Notable climatic stressors and events, including drought, strong winds, high temperatures, among others, all intersect to drive migration. Even though the role of environmental factors in migration decision-making is hotly debated, coupled with the fact that there is no consensus on the direct influence of extreme weather events and stressors on migration (Mastrorillo et al., 2016 [48]), several studies in diverse geographic locations report the significant role of environmental factors in fueling migration. Nguyen and Sean (2021) [7], for instance, discovered that climate change affects farming systems—manifesting in declined or loss of rice yield, soil infertility, and unharvested and immature crops impacting farmers’ migration to cities in Cambodia. Similar evidence is found in other contexts, such as Mexico (see Jessoe, Manning, and Taylor, 2018 [49]; Nawrotzki, Riosmena, and Hunter, 2013 [50]), and the Philippines (see Bohra-Mishra et al. 2017 [51]).

Reviewed studies also document migration as an adaptation strategy amidst climatic shocks and events. Thus, internal or international migration is conceived as one of the adaptation mechanisms to reduce risks associated with climatic events. The theme of migration as an adaptation strategy resonates with similar findings in other places, such as Bangladesh (see Petrova, 2021 [52]; Stojanov et al., 2016 [53]), Pakistan (see Gioli et al., 2014 [54]), and India (see Jha et al., 2018 [55]). In examining migration as a climate change adaptation approach for Bangladeshis, Stojanov et al. (2016) [53] notice that local experts consider migration as an ad hoc strategy to mitigate worsening climate conditions in the region. However, the authors are quick to add that migration is not only for climate change adaptation, instead interlaced with other forces affecting migration-related decisions. However, another school of thought suggests that migration due to climate change impacts is a two-edged sword. Specifically, drawing on examples from Alaska and Kiribati, McNamara et al. (2016) [56] argue that relocation of people as a result of climate change impact is both an adaptation strategy and the cause of serious losses and damages in economic, social, culture, and psychological areas.

Our reviewed studies also demonstrate the fact that migration decision making in the context of climatic shocks and events is not always dependent on environmental factors. Rather, several factors, such as economic, political, social, cultural, among other variables, intermingle to drive human mobility amidst climate change. Thus, the drivers of climate-induced migration are complex and multifold (Ibrahim and Mensah, 2022 [15]). It is this complexity and multiplicity of factors that compel some scholars to argue that differentiating climate-related migration drivers from other socio-economic and political factors is difficult (Rabbani et al., 2022 [57]). From this systematic review on Africa, it is evident that both environmental and non-environmental factors influence migration. Nagabhatla et al. (2021) [31], for instance, demonstrate that among pastoralists in Congo Basin and the Mborobo, an interplay of factors, including conflicts, resource scarcity, and other political, social, and economic stressors intersect to drive forced migration and IDPS. Similar evidence is found in China, where Shi et al. (2019) [58] note that within the context of climate change, political, economic, and social factors are strong variables that directly drive internal migration, while demographic and environmental forces are moderate or weak factors that indirectly foster internal migration.

Our systematic literature review also reveals that in the context of climate change, some people decide to stay put for several reasons. This revelation supports emerging scholarship on immobility and climate change and challenges the long-held notion that affected people are more likely to migrate amidst climate change concerns. Three of the reviewed studies emphasize the climate change–immobility nexus. This theme resonates with the broader literature and empirical studies on this theme in different geographic locations, including Ghana (see Kutor et al., forthcoming [59]), Indonesia (see Amin et al., 2021 [60]), and Fiji (see Farbotko, 2018 [61]). Specifically, Amin et al. (2021) [60] discover that among residents of coastal Semarang, Indonesia, place attachment, social, family, and occupational ties are migration holding factors. Similarly, Kutor et al. (forthcoming) [59] demonstrate that among three coastal communities in Ghana, the holding factors for immobility amidst climate change-induced coastal flooding include place attachment, livelihood opportunities, and low mobility prospects.

7. Conclusions and Implications

Based on insights from twenty-two (22) studies, this systematic review has provided an up-to-date state of knowledge on the existing literature on climate change and migration in Africa. Such knowledge is important in order to continue to shape discourses around climate change and migration. The findings suggest that the relationship between climate change impacts and migration is complex and multilayered, rather than straightforward. Five main themes have emerged from our analysis: (1) environmental factors influencing migration, (2) migration as an adaptation strategy, (3) environmental and non-environmental forces influencing migration, (4) climate change and internal migration, and (5) climate change and immobility. Even though these themes are receiving academic attention in the study of migration in Africa, this review has three main scientific contributions. First, the current study helps in comprehending how the literature has metamorphosed in connection with evolving times. Second, the current study helps to systematically synthetize and itemize these themes to determine the state of scholarship on climate-induced migration in Africa. Third, this study identifies gaps in the existing scholarship and offers a new research agenda, especially focusing on policy interventions to address climate-induced migration in order to improve livelihoods and other development-related outcomes.

Even though the literature on climate change and migration is growing in Africa, there is a need for more policy-oriented research that examines the policy implications of climate change and migration. Future research should examine the policy dimensions of climate change and migration in Africa.

Despite the importance of issues raised in this systematic review, some limitations must be considered. First, due to language barriers on the part of the research team, the review excludes non-English peer-reviewed articles. Second, grey literature is not included in the systematic review. Thus, some interesting perspectives may have been omitted. Despite these limitations, this systematic review provides a comprehensive evaluation of climate change and migration in Africa using standard systematic review strategies. The search guidelines were exhaustive and robust, retrieving papers based on multiple keywords and their synonyms, and utilizing several databases. The inclusion and exclusion criteria were also rigorously defined and implemented. Overall, this systematic review enhances our comprehension of environmental factors influencing migration, migration as an adaptation strategy, environmental and non-environmental forces influencing migration, climate change and internal migration, and climate change and immobility.

The findings of this systematic review have policy implications for practitioners and policymakers in the field of climate change and migration. This is because climate change is recognized as a key driver of mobility in the Agenda for Humanity, the 2016 United Nations Summit for Refugees and Migrants, and the Global Compact for Migration and the Global Compact on Refugees. Moreso, the 2030 Sustainable Development Goals (SDGs) include a target (10.7) to “facilitate orderly, safe, and responsible migration and mobility of people, including through implementation of planned and well-managed migration policies”. These international organizations and frameworks on climate change and migration have implications for national governments who are signatories to these frameworks. With the evidence that environmental and non-environmental factors are influencing migration, it is imperative for national governments in Africa and development partners to implement policies that address the complex and manifold drivers of climatic shocks and events. How to achieve this is not easy, but efforts must be made towards that agenda by African national governments. Furthermore, the fact that our reviewed studies show that some people choose to stay put amidst climate change contexts raises important issues for African governments. African governments must investigate why some people stay put and the dynamics (e.g., gendered roles) to that in order to design appropriate in situ or ex situ adaptation measures to support their livelihoods. Importantly, these adaptation strategies must be sustainable in order to avoid becoming maladaptive in the future.