Environmental Change and Migration

What are the generalised, large scale factors of the environment-migration relationship and to what extent is it conditional on various individual, socio-economic, and political factors?

Project Summary

The debate on whether and how environmental changes affect human security and, ultimately, force people to leave their homes and migrate to places more conducive to their wellbeing, has experienced a strong revival in the climate change context.

While various studies predict large environmental migration flows due to climate change and other environmental disorders, they do not investigate sufficiently whether the relationship between climate change and migration holds for a large set of countries and for different types of environmental afflictions.

Most importantly also, the environment-migration relationship may be conditional on various individual, socio-economic, and political factors. This project aims at filling several of the theoretical, empirical, and methodological gaps that do persist in the existing literature in order to gain a better understanding of whether, when, and how environmental change might lead to migration.

The findings of this research may be used by international organisations, such as the International Organisation for Migration (IOM) and the United Nations High Commissioner for Refugees (UNHCR) that seek to develop effective policies and programmes for dealing with environmental migration.

Executive Summary

This project contributes to the existing literature on the environmental change–migration nexus along the following lines: at the theoretical level, it proposes an argument that systematically links different types of environmental stressors– notably short- vs. long-term environmental events– as well as individual perceptions of the environmental event to decisions of individuals to migrate or stay. At the empirical level, it tests the plausibility of the arguments, using original survey data from Vietnam, Cambodia, Uganda, Nicaragua and Peru, including both individuals who migrated and individuals who decided to stay. It also implements an agent-based model (ABM) to simulate climate-induced migration for alternative future climate scenarios using the newly collected micro-level data to calibrate the model. Results from the survey in Vietnam show that sudden and short-term environmental weather events significantly increase the likelihood that an individual opts for migration, while slow-onset and long-term environmental events do either not influence or significantly reduce the likelihood of migration. Furthermore the computation results indicate that migration flows will increase in the future mainly due to the increase in the frequency of sudden and short-term environmental weather events such as heavy precipitation.

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Working Paper

Environmental Change and Migration

What is the role of environmentally induced migration in the climate-change context? While there is broad consensus that environmental factors might affect human mobility, the ex-post empirical evidence on this is inconclusive. This research contributes to the emerging empirical literature in this field by examining whether and how environmental change leads to internal (i.e., domestic) migration at the micro level. It is argued that individual perceptions of and attitudes toward different types of environmental change determine migration decisions in diverse ways. Empirically, the corresponding argument is analyzed with newly collected survey data from five developing countries, which include both individuals who migrated and individuals who decided to stay. The results suggest that individual perceptions of and attitudes toward long-term environmental events, such as droughts, have no significant effect on internal migration. However, sudden-onset environmental events, such as floods, significantly increase the chances to move. These findings suggest that “climate-refugee scenarios” are likely to be exaggerated and, hence, a more differentiated perspective on the issue of environmental migration based on adaptation is needed.

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Working Paper

Environmental Migration Flows in Vietnam

The argument that environmental change is an important driving force of migration has experienced a strong revival in the climate change context. Yet, knowledge in this issue remains limited and fragmented. In his paper we contribute to the literature in this field by focusing on the micro-level. We examine whether and how individual perceptions of different types of environmental events (i.e., sudden and short-term environmental events such as storms vs slow-onset and long-term environmental events such as droughts) affect migration decisions. Using a computational model, we simulate the climate-induced migration for alternative future climate scenarios. Newly collected micro-level data (1,200 migrants and non-migrants) from Vietnam is used to calibrate the model. Results show that migrants perceive sudden and short-term environmental events as more extreme compared to non- migrants; in the future the average proportion of migration among individuals increases due to increases in heavy precipitation events.

Article

Environmental Stressors and Migration: Evidence from Vietnam

The argument that environmental change is an important driving force of migration has experienced a strong revival in the climate change context. While various studies predict large environmental migration flows due to climate change and other environmen- tal events, the ex post empirical evidence for this phenomenon is inconclusive. We contribute to the extant literature by focusing on the micro-level. We examine whether and how individual perceptions of different types of environmental stressors induce internal migration. The analysis relies on original survey data from Vietnam including both migrants and non-migrants. The results suggest that individual perceptions of long-term environmental events, such as droughts, significantly reduce migration while perceptions of sudden-onset environmental events, such as floods, significantly increase the likelihood of migration controlling for other determinants of migration. These findings also imply that improving the targeting of aid to environmental disaster-affected areas and the financial and technical support for adaptation to environmental change could be the most productive policy-options. Policymakers, thus, need to implement a wide range of developmental policies in combination with environmental ones in order to improve society’s ability to effectively cope with environmental change and minimize its effect on migration.

Article

The role of environmental perceptions in migration decision-making: evidence from both migrants and non- migrants in five developing countries

Research has demonstrated that, in a variety of settings, environmental factors influence migration. Yet much of the existing work examines objective indicators of environmental conditions as opposed to the environmental perceptions of potential migrants. This paper examines migration decision-making and individual perceptions of different types of environmental change (sudden vs. gradual environmental events) with a focus on five developing countries: Vietnam, Cambodia, Uganda, Nicaragua, and Peru. The survey data include both migrants and non-migrants, with the results suggesting that individual perceptions of long-term (gradual) environmental events, such as droughts, lower the likelihood of internal migration. However, sudden-onset events, such as floods, increase movement.

These findings substantially improve our understanding of perceptions as related to internal migration and also suggest that a more differentiated perspective is needed on environmental migration as a form of adaptation.

Article

Perceptions of environmental change and migration decisions

While climate change is projected to increase displacement of people, knowledge on this issue remains limited and fragmented. In his paper we focus on the micro-level and study the effects of individual perceptions of different types of environmental events (i.e., sudden/short-term vs. slow-onset/long-term) on migration decisions. Our results based on newly collected micro-level survey data from Vietnam shows that while slow-onset environmental events, such as droughts, significantly decrease the likelihood of migration, short-term events, such as floods, are positively related to migration, although not in a statistically significant way. When contrasting individual level perceptions with actual climatic events we observe that migrants and non-migrants perceive both long-term as well as sudden-onset environmental events in different ways. While non-migrants are slightly better in judging the actual extremeness of events such as floods and hurricanes, it is the migrants who are slightly better in judging the actual extremeness in the case of droughts.

Article

The Determinants of Environmental Migrants’ Conflict Perception

Migration is likely to be a key factor linking climate change and conflict. However, our understanding of the factors behind and consequences of migration is surprisingly limited. We take this shortcoming as a motivation for our research and study the relationship between environmental migration and conflict at the micro level. In particular, we focus on environmental migrants’ conflict perceptions. We contend that variation in migrants’ conflict perception can be explained by the type of environmental event people experienced in their former home, whether gradual, and long-term or sudden-onset, short-term environmental changes. We develop this argument before quantitatively analyzing newly collected micro-level data on intra-state migration from five developing countries. The results emphasize that migrants who experienced gradual, long-term environmental events in their former homes are more likely to perceive conflict in their new location than those having experienced sudden, short-term environmental events. These findings are in line with our theoretical argument that environmental migrants who suffer from environmentally induced grievances are ultimately more likely to perceive conflict and challenges in their new locations.

Article

Climate events and the role of adaptive capacity for (im-)mobility

The study examines the relationship between sudden- and gradual-onset climate events and migration, hypothesizing that this relationship is mediated by the adaptive capacity of affected individuals. We use survey data from regions of Cambodia, Nicaragua, Peru, Uganda, and Vietnam that were affected by both types of events with representative samples of non-migrant residents and referral samples of migrants. Although some patterns are country-specific, the general findings indicate that less educated and lower-income people are less likely to migrate after exposure to sudden-onset climate events compared to their counterparts with higher levels of education and economic resources. These results caution against sweeping predictions that future climate-related events will be accompanied by widespread migration.

Research Team

Vally Koubi
Coordinator
University of Berne

Tobias Böhmelt
Co-Coordinator
Eidgenössische Technische Hochschule Zürich

Gabriele Spilker
Co-Coordinator
Eidgenössische Technische Hochschule Zürich

Lucas Beck
Principal Member
Eidgenössische Technische Hochschule Zürich

Tobias Siegfried
Principal Member
Eidgenössische Technische Hochschule Zürich

Status

completed

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SDGs

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Regions

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