Putting trapped populations into place: Climate change and inter-district migration flows in Zambia

The impacts of climate change on violent conflict risk: a review of causal pathways

The potential impacts of climate change on violent conflict are high on the agenda of scholars and policy makers. This article reviews existing literature to clarify the relationship between climate change and conflict risk, focusing on the roles of temperature and precipitation. While some debate remains, substantial evidence shows that climate change increases conflict risk under specific conditions. We examine four key pathways through which climate affects conflict: (i) economic shocks, (ii), agricultural decline, (iii) natural resources competition, and (iv) migration. Key gaps include limited long-term data, insufficient integrated studies, and the inadequate understanding of causal mechanisms, necessitating transdisciplinary research that addresses social vulnerability and underlying pathways.

Understanding the global subnational migration patterns driven by hydrological intrusion exposure

Amid the escalating global climatic challenges, hydrological risks significantly influence human settlement patterns, underscoring the imperative for an in-depth comprehension of hydrological change's ramifications on human migration. However, predominant research has been circumscribed to the national level. The study delves into the nonlinear effects of hydrological risks on migration dynamics in 46,776 global subnational units. Meanwhile, leveraging remote sensing, we procured globally consistent metrics of hydrological intrusion exposure, offering a holistic risk assessment encompassing hazard, exposure, and vulnerability dimensions, thus complementing previous work. Here, we show that exposure is the primary migration driver, surpassing socioeconomic factors. Surrounding disparities further intensified exposure's impact. Vulnerable groups, especially the economically disadvantaged and elderly, tend to remain in high-risk areas, with the former predominantly migrating within proximate vicinities. The nonlinear analysis delineates an S-shaped trajectory for hydrological exposure, transitioning from resistance to migration and culminating in entrapment, revealing dependence on settlement resilience and adaptability.

Zambia: A Narrative Review of Success and Challenges in Lymphatic Filariasis Elimination

The establishment of the Global Programme to Eliminate Lymphatic Filariasis (GPELF) to stop the transmission of infection has significantly reduced the incidence of lymphatic filariasis, a debilitating mosquito-borne neglected tropical disease. The primary strategies that have been employed include mass drug administration (MDA) of anthelminthics and morbidity management and disability prevention (MMDP). While some countries have been able to reach elimination status in Africa, there is still active transmission of LF in Zambia. The nematode responsible for the disease is Wuchereria bancrofti, which is transmitted by Anopheles mosquitoes. To alleviate the suffering of those infected by the disease, the Zambian Ministry of Health launched a program to eliminate LF as a public health problem in 2003. This project reviewed the efforts to achieve the elimination of LF in Zambia, past and present government policies, and the anticipated challenges. MDAs have been conducted since 2014 and coverage has been between 87% and 92%. Zambia has now moved towards pre-transmission assessment surveys (PRETAS) and transmission assessment surveys (TAS). MMDP is a major priority and planned to be conducted between 2022 and 2026. COVID-19 presented a new challenge in the control of LF, while climate change, immigration, co-infections, and funding limitations will complicate further progress.

How do environmental stressors influence migration? A meta-regression analysis of environmental migration literature

BACKGROUND

The amount of literature on environmental migration is increasing. However, existing studies exhibit contradictory results. A systematic synthesis of the environment-migration relationship is much needed.

OBJECTIVE

This study summarizes research findings, calculates the effect sizes of environmental stressors, identifies publication bias, and investigates heterogeneous environmental effects on migration.

METHODS

We collected 3,380 estimates from 128 studies published between 2000 and 2020 to explore the environment-migration relationship and performed weighted instrumental variable regression to unveil the heterogeneous environmental effects on out- and net migration.

RESULTS

The majority of environmental stressors were not important predictors of out- and net migration. Among the results showing environmental impacts on migration, 58% and 68% reported that environmental stressors increased out- and net migration, respectively, while 58% reported that environmental stressors decreased in-migration. The overall environmental impact on migration was small; however, disaster-related stressors showed a medium effect, and rapid-onset stressors had a stronger impact than slow-onset ones. Multivariate meta-regression analyses demonstrated that environmental stressors were more likely to trigger internal migration than international migration and that developed countries were less likely to experience out-migration. Rapid-onset environmental stressors did not increase out-migration but played an important role in decreasing net migration toward environmentally stressed areas. Meanwhile, we also found a publication bias toward studies showing a positive relationship between environmental stressors and migration in the previous environmental migration literature.

CONCLUSIONS

Environmental stressors may affect migration; however, the environmental effect depends on migration measurements, environmental stressors' forces and rapidity, and the context in which migration takes place.

CONTRIBUTION

This study contributes to migration studies by synthesizing and validating the environment-migration relationship and enhancing our understanding of how and under what circumstances environmental stressors may affect migration.

Child Fostering in a Changing Climate: Evidence from Sub-Saharan Africa

An extensive social science literature has examined the effects of climate change on human migration. Prior studies have focused largely on the out-migration of working-age adults or entire households, with less attention to migration and other forms of geographic mobility among other age groups, including youth. In this study, we focus on the implications of climate variability for the movement of children by examining the association between climate exposures and the in- and out-fostering of children in sub-Saharan Africa. We link high-resolution temperature and precipitation records to data from the Demographic and Health Surveys for 23 sub-Saharan African countries. We fit a series of regression models to measure the overall associations between climate exposures and each outcome, and then evaluate whether these associations are moderated by socioeconomic status, the number of children in the household, and the prevalence of fostering in each country. Precipitation is positively associated with in-fostering overall, and these effects are especially strong among households who already have at least one child and in countries where child fostering is common. We find no overall relationship between either temperature or precipitation exposures and out-fostering, but we do detect significant effects among households with many children and those with more-educated heads. In sum, our findings suggest climate variability can influence child mobility, albeit in complex and in some cases context-specific ways. Given the socioeconomic and health implications of fostering, these results underline another pathway through which climate exposures can affect children's wellbeing. More broadly, this study shows that new attention to the links between climate variability, child fostering, and other understudied forms of spatial mobility is needed to fully understand the effects of climate change on human populations.

Heat and Drought Reduce Subnational Population Growth in the Global Tropics

In recent decades, the possibility that climate change will lead to depopulation of vulnerable areas in the global tropics via migration, mortality, or collapsing fertility has generated significant concern. We address this issue by using data on subnational population growth from 1,809 subnational units across the global tropics and linked data on climate exposures to examine how decadal temperature and precipitation anomalies influence population-weighted intercensal growth rates. Our fixed effects regression analysis reveals that the lowest predicted population growth rates occur under hot and dry conditions. The effects of heat and drought are strongest in districts that, at baseline, have high population densities, high precipitation rates, or high educational attainment. These patterns are contrary to common assumptions about these processes, and even the rare combination of hot and dry conditions, occurring in less than 7% of our sample, does not lead to local depopulation. Taken together with previous findings, this suggests that depopulation narratives do not have a strong evidentiary basis.

Natural resources modulate the nexus between environmental shocks and human mobility

In the context of natural resource degradation, migration can act as means of adaptation both for those leaving and those supported by remittances. Migration can also result from an inability to adapt in-situ, with people forced to move, sometimes to situations of worse or of the same exposure to environmental threats. The deleterious impacts of resource degradation have been proposed in some situations to limit the ability to move. In this contribution, we use remote sensed information coupled with population density data for continental Africa to assess quantitatively the prevalence of migration and immobility in the context of one cause of resource degradation: drought. We find that the effect of drought on mobility is amplified with the frequency at which droughts are experienced and that higher income households appear more resilient to climatic shocks and are less likely to resort to mobility as an adaptation response.

Post-disaster (im)mobility aspiration and capability formation: case study of Southern California wildfire

Scholarship on the environmental dimensions of migration demonstrates the complex interplay of climatic and non-climatic factors which combine to create a potential for migration. Yet in times of environmental crisis or change, not everyone aspires to or is capable of moving to reduce their vulnerability. When, why, and how populations vulnerable to hazard risks decide not to migrate remains a significant gap in our understanding of the migration-environment relationship. Analysis of data from 38 qualitative interviews shows how Los Angeles County residents-after surviving the 2018 Woolsey Fire-developed aspirations to stay and/or rebuild, depending on the attachments and meanings associated with their communities. This paper also seeks to clarify the concept of capabilities to stay by considering separately the capabilities to return and rebuild from the capabilities to cultivate preparedness. Many who stayed also worked to strengthen community resilience to alleviate concerns of future wildfire risk. Some residents expressed individual commitments to stay and defend homes during future fires, while well-equipped volunteer fire brigades have proliferated in more affluent areas. Community mobilizations pressured local government and fire services to address the perceived institutional failure during previous fire responses and fostered feelings of collective efficacy among residents which increased their confidence to remain in high wildfire risk communities.

The Childhood Origins of Climate-Induced Mobility and Immobility

The literature on climate exposures and human migration has focused largely on assessing short-term responses to temperature and precipitation shocks. In this paper, we suggest that this common coping strategies model can be extended to account for mechanisms that link environmental conditions to migration behavior over longer periods of time. We argue that early-life climate exposures may affect the likelihood of migration from childhood through early adulthood by influencing parental migration, community migration networks, human capital development, and decisions about household resource allocation, all of which are correlates of geographic mobility. After developing this conceptual framework, we evaluate the corresponding hypotheses using a big data approach, analyzing 20 million individual georeferenced records from 81 censuses implemented across 31 countries in tropical Africa, Latin America, and Southeast Asia. For each world region, we estimate regression models that predict lifetime migration (a change in residence between birth and ages 30-39) as a function of temperature and precipitation anomalies in early life, defined as the year prior to birth through age four. Results suggest that early-life climate is systematically associated with changes in the probability of lifetime migration in most regions of the tropics, with the largest effects observed in sub-Saharan Africa. In East and Southern Africa, the effects of temperature shocks vary by sex and educational attainment and in a manner that suggests women and those of lower socioeconomic status are most vulnerable. Finally, we compare our main results with models using alternative measures of climate exposures. This comparison suggests climate exposures during the prenatal period and first few years of life are particularly (but not exclusively) salient for lifetime migration, which is most consistent with the hypothesized human capital mechanism.

Shifting Safeties and Mobilities on the Land in Arctic North America: A Systematic Approach to Identifying the Root Causes of Disaster

Amid the surge in research on mobility and migration in the context of environmental change, little research has focused on the experiences of people for whom travel is cyclical and a part of daily, weekly, or seasonal life. For Inuit in Arctic North America, the land is the heart of cultural and community life. Disruption to time spent on the land is reported to impact the emotional health and well-being of individuals and communities. There is concern that environmental change is creating barriers to safe travel, constituting a creeping disaster. We systematically review and evaluate the literature for discussion of barriers to travel for Inuit in Arctic North America, using an approach from the field of disaster anthropology to identify root causes of constraints to mobility. We identify root causes of risk and barriers to time spent on the land. These emerge from historic and contemporary colonial policy and inequality, as opposed to environmental hazards per se, impacting people’s mobility in profound ways and enacting a form of slow violence. These results suggest a need to understand the underlying processes and institutions that put people at risk.

Climate change and non-migration - exploring the role of place relations in rural and coastal Bangladesh

Of growing research and policy interest are the experiences of people living under conditions of climate change-induced environmental stress, which either are unable to migrate (sometimes described as a 'trapped population') or are seemingly unwilling to do so (sometimes described as the 'voluntarily immobile'). This paper problematises and expands upon these binary categories: examining the complex dimensionality of non-migration as a form of place relations, explored through qualitative study of rural and coastal Bangladeshi communities. Through 60 semi-structured interviews of individuals from four communities in the Kalapara region, the analysis proffers four qualitatively derived and inter-related dimensions of voluntary and involuntary non-migration framed as a form of place relations. These four dimensions concern the following: (1) livelihood opportunities, (2) place obduracy, (3) risk perceptions, and (4) social-structural constraints, with the interplay between these elements explaining diverse non-migratory experiences. In our analysis, 'place obduracy' is introduced as a concept to describe the differential speed of environmental change and socio-cultural adaptation responses to explain non-migratory experiences. Our discussion provides insight into how to best support non-migrant people's adaptive capacity in the face of growing climate emergency.

Exploring the Climate Temperature Effects on Settlement Intentions of Older Migrants: Evidence from China

Permanent migration across provinces in China has become an important strategy for Chinese older people to respond to a temperature-unfriendly place of residence in late life. However, the relation between temperature effects and permanent settlements of older migrants remains unclear. Based on the data obtained from China Migrants Dynamic Survey, this paper examined how four temperature effects (i.e., cold effect, heat effect, temperature gap effect, and temperature zone effect) play a role in shaping older migrants’ intentions to settle permanently in a destination place by conducting logistic regression analysis. Our findings show that: (1) extreme cold (rather than extreme heat or mild temperature) was found to have significant effects on settlement intentions of older people; (2) relative winter temperature between origin and destination places rather than absolute winter temperature in the destination place has a significant positive effect on the settlement intentions; (3) spatially, older migrants tend to migrate to geographically adjacent temperature zones. Our findings will inform a more effective planning and allocation of services for supporting older people by better understanding trends and intentions of older migrants.

Operationalizing and empirically identifying populations trapped in place by climate and environmental stressors in Mexico

In this paper, we propose a guiding operational definition and corresponding set of empirical steps to identify and study trapped populations. Trapped populations consist of actors who are highly vulnerable to climate and environmental stressors given limited resources (economic, social, etc.), which limit their ability to adapt to these stressors in-situ or by choosing to migrate. Informed by both insights and omissions from prior theoretical and empirical research, we propose a guiding operational definition of trapped populations that appreciates and incorporates actors' limited resources and their migration intentions against the backdrop of climate and environmental stressors. As it should, our operational definition points to a specific set of operations, or steps, which can be followed to empirically identify and study trapped populations. Using data from the Mexican Family Life Survey (MxFLS), we detail the steps permitting both retrospective and prospective identification of trapped populations. We conclude by discussing the strengths and weaknesses of our operational definition and empirical approach, as well as possible extensions.

In harm's way: Non-migration decisions of people at risk of slow-onset coastal hazards in Bangladesh

Non-migration is an adaptive strategy that has received little attention in environmental migration studies. We explore the leveraging factors of non-migration decisions of communities at risk in coastal Bangladesh, where exposure to both rapid- and slow-onset natural disasters is high. We apply the Protection Motivation Theory (PMT) to empirical data and assess how threat perception and coping appraisal influences migration decisions in farming communities suffering from salinization of cropland. This study consists of data collected through quantitative household surveys (n = 200) and semi-structured interviews from four villages in southwest coastal Bangladesh. Results indicate that most respondents are unwilling to migrate, despite better economic conditions and reduced environmental risk in other locations. Land ownership, social connectedness, and household economic strength are the strongest predictors of non-migration decisions. This study is the first to use the PMT to understand migration-related behaviour and the findings are relevant for policy planning in vulnerable regions where exposure to climate-related risks is high but populations are choosing to remain in place.

Climate change-induced migration: a bibliometric review

Background

This paper has reviewed the international research on the terms “climate change” and “human migration” from 1999 to 2019. To this end, a bibliometric and a cluster analysis by fractional accounting have been carried out using two of the most important databases: Web of Science (WoS) and Scopus. The research found and studied 140 documents from WoS Core Collection and 193 from Scopus.

Results

The results show a continual increase in the number of articles published and citations received during the whole period studied. The U.S., U.K., Germany and China have been shown to be the most productive countries and there is a predominance of North American organizations supporting and fostering research on these topics.

Conclusions

The main contribution of this article is the analysis of new tendencies. The trend shows a transition from concepts such as vulnerability, climate change, land degradation, refugees and security to others such as concepts such as international migration, climate justice, sustainability, human rights and disaster risk reduction. Future research in this field should address the comparison of results from research focused on human beings to a focus on other living beings.

The Differential Influence of Geographic Isolation on Environmental Migration: A Study of Internal Migration Amidst Degrading Conditions in the Central Pacific

This study investigates how geographic isolation interacts with declining environmental and economic conditions in Kiribati, an island nation wherein which limited access to financial resources amidst degrading environmental conditions potentially constrain capital-intensive, long distance migration. We examine whether geographic isolation modifies the tenets of two dominant environmental migration theses. The environmental scarcity thesis suggests that environmental degradation prompts migration by urging households to reallocate labor to new environments. In contrast, the environmental capital thesis asserts that declining natural resource availability restricts capital necessary for migration. Results show that the commonly applied environmental scarcity thesis is less valid and the environmental capital thesis is more relevant in geographically isolated places. Findings indicate that geographic isolation is an important dimension along which migration differences emerge. As overall environmental and economic conditions worsen, likelihoods of out-migration from less remote islands increase whereas likelihoods of out-migration from more isolated islands decrease.

Why climate migration is not managed retreat: Six justifications

This perspective piece makes a case for a more rigorous treatment of managed retreat as a politically, legally, and economically distinct type of relocation that is separate from climate migration. We argue that the use of both concepts interchangeably obfuscates the problems around climate-induced mobilities and contributes to the inconsistencies in policy, plans, and actions taken by governments and organizations tasked with addressing them. This call for a disentanglement is not solely an academic exercise aimed at conceptual clarity, but an effort targeted at incentivizing researchers, practitioners, journalists, and advocates working on both issues to better serve their constituencies through alliance formation, resource mobilization, and the establishment of institutional pathways to climate justice. We offer a critical understanding of the distinctions between climate migration and managed retreat grounded in six orienting propositions. They include differential: causal mechanisms, legal protections, rights regimes and funding structures, discursive effects, implications for land use, and exposure to risks. We provide empirical examples from existing literature to contextualize our propositions while calling for a transformative justice approach to addressing both issues.

Climate-Induced Migration and Unemployment in Middle-Income Africa

One of the major unresolved questions in the study of vulnerability to climate change is how human migration will respond in low and middle-income countries. The present study directly addresses this lacuna by using census data on migration from 4 million individuals from three middle-income African countries over a 22-year period. We link these individuals to climate exposures in their origins and estimate climatic effects on migration using a fixed-effects regression model. We show that climate anomalies affect mobility in all three countries. Specifically, mobility declines by 19% with a 1-standard deviation increase in temperature in Botswana. Equivalent changes in precipitation cause declines in migration in Botswana (11%) and Kenya (10%), and increases in migration in Zambia (24%). The mechanisms underlying these effects appear to differ by country. Negative associations between precipitation anomalies, unemployment, and inactivity suggest migration declines may be due to an increased local demand for workers to offset production risk, while migration increases may be indicative of new opportunities in destinations. These country-specific findings highlight the contextually-specific nature of climate-migration relationships, and do not support claims that climate change is widely contributing to urbanization across Africa.

Trapped or Voluntary? Non-Migration Despite Climate Risks

Millions of people impacted by climate change actually want to remain in place; these aspirations and respective capabilities need more attention in migration research and climate adaptation policies. Residents at risk may voluntarily stay put, as opposed to being involuntarily trapped, and understanding such subjectivity is empirically challenging. This comment elaborates on “voluntary non-migration” to call attention to a neglected population within the ongoing discourses on climate-induced migration, social equality and human rights. A roadmap for action outlines specific research and policy goals.

Internal Migration in the United States: A Comprehensive Comparative Assessment of the Consumer Credit Panel

BACKGROUND

We introduce and provide the first comprehensive comparative assessment of the Federal Reserve Bank of New York/Equifax Consumer Credit Panel (CCP) as a valuable and underutilized dataset for studying internal migration within the United States. Relative to other data sources on US internal migration, the CCP permits highly detailed cross-sectional and longitudinal analyses of migration, both temporally and geographically.

OBJECTIVE

We seek to demonstrate the comparative utility and some of the unique advantages of the CCP relative to other data sources on US internal migration.

METHODS

We compare cross-sectional and longitudinal estimates of migration from the CCP to similar estimates derived from the American Community Survey, the Current Population Survey, Internal Revenue Service data, the National Longitudinal Survey of Youth, the Panel Study of Income Dynamics, and the Survey of Income and Program Participation.

RESULTS

Our results firmly establish the comparative utility and clearly illustrate some of the unique advantages of the CCP relative to other data sources on US internal migration.

CONCLUSIONS

We conclude by identifying some profitable directions for future research on US internal migration using the CCP, as well as reminding readers of the strengths and limitations of these data.

CONTRIBUTION

We provide an introduction to the CCP as a comprehensive comparative point of reference to stimulate future research on US internal migration using these data. More broadly, this paper contributes to research on the use of non-traditional data sources to study migration given well-documented problems with the availability, quality, and comparability of migration data from traditional sources.

Do Social Protection Programs Foster Short-term and Long-term Migration Adaptation Strategies?

We examine how migration is influenced by temperature and precipitation variability, and the extent to which the receipt of a cash transfer affects the use of migration as an adaptation strategy. Climate data is merged with georeferenced panel data (2010-2014) on individual migration collected from the Zambian Child Grant Program (CGP) sites. We use the person-year dataset to identify the direct and heterogeneous causal effects of the CGP on mobility. Having access to cash transfers doubles the rate of male, short-distance moves during cool periods irrespective of wealth. Receipt of cash transfers (among wealthier households) during extreme heat causes an additional retention of males. Cash transfers positively spur long-distance migration under normal climate conditions in the long term. They also facilitate short-distance responses to climate, but not long-distance responses that might be demanded by future climate change.

Temporary Migration and Climate Variation in Eastern Africa

Africa is likely to experience warming and increased climate variability by the late 21st century. Climate extremes have been linked to adverse economic outcomes. Hence, adaptation is a key component of the United Nations Framework Convention on Climate Change agreements and development assistance. Effective climate adaptation policy requires an understanding of how temperature and rainfall variability affect migration patterns. Yet, how individuals in developing countries manage climate variation is poorly understood, especially in Africa. Combining high-resolution climate data with panel micro-data on migration, labor participation, and demographics, we employ regression analysis to assess temporary migration responses to local temperature and precipitation anomalies in four East African countries. We find that climate impacts are most pronounced in urban areas, with a standard deviation temperature increase and rainfall decrease leading to respective 10 and 12 percent declines in out-migration relative to mean values. Evidence from other labor market outcomes suggests that urban out-migration is not associated with reduced local employment opportunities. Instead, declines in urban out-migration appear to coincide with negative local climate employment impacts. These results challenge the narrative that temporary out-migration serves as a safety valve during climate extremes and that climate change will most strongly affect out-migration rates from rural areas in developing countries.

Keeping People in Place: Political Factors of (Im)mobility and Climate Change

While those ‘trapped’ or who choose to stay in areas affected by climate change represent a substantial policy issue, there only a small amount of empirical work specifically targeting such populations. The scant attention that is afforded to immobility often emphasizes financial constraints as factors driving (involuntary) immobility. As an essential part of the mobility spectrum, the complexity of immobility in crisis, including its political dimensions, warrants thorough investigation. In response to these gaps, this contribution locates environmental immobility within mobilities studies, its conceptual complexities, and, finally, illustrates the importance of political factors in shaping (im)mobilities. The findings are based on semi-structured interviews conducted in two developing countries experiencing the impacts of climate change. We delve into the socio-cultural and economic nature of (im)mobilities as they interact with political forces, specifically by exploring international bilateral agreements (Senegal) and a relocation program (Vietnam). In political spaces that are dominated by a desire to limit human mobility and (re)produce stasis, we challenge traditional dichotomies between mobile/immobile and sedentary/migration polices by underlining how policy interventions can simultaneously promote mobility and immobility, demonstrating complex co-existing mobilities. Keeping people in place can, in fact, mean allowing the very same people to move.

Climate Migration at the Height and End of the Great Mexican Emigration Era

Previous research has linked increasing climate-change-related variability to Mexico-US migration, but only under particular climatic/social conditions and periods of high irregular migration. Using the 2000 and 2010 Mexican censuses, we examine this environment-migration nexus across a broader set of socioecological contexts and during periods of both increasing (1995-1999) and declining (2005-2009) migration. Consistent with the notion that climate can "trap" populations in place, we find that frequent/severe bouts of hot or dry conditions are associated with lower US-bound migration from most of rural Mexico. However, we do find higher climate outmigration during episodes hot and dry climate, or out of places with lower vulnerability. Our comparisons across periods suggest that climate migration is affected by conditions in the U.S. in a similar or slightly weaker manner as other forms of migration are. Altogether, our findings suggest that rural Mexico is unlikely to push large numbers of international "climate refugees" and that climate migration is indeed sensitive to conditions in sending and destination areas.