Crossing borders


Projections of the effect of climate change on global mobility (CLIMATE)

In the 21st century, climate change will cause temperature changes, rising sea levels, and more frequent and intense heat waves, extreme weather events, and natural disasters. The damages resulting from climate change will vary between and within countries based on factors such as proximity to seas and oceans, land topography, industry structure, and initial temperature levels.

Predicting and modelling migration responses to long-term climate change is a complex task. In addition to uncertainties surrounding expected climate changes, climate variables interact with various economic and political drivers of migration, such as income and health. Furthermore, mobility decisions are context-specific and influenced by numerous factors that differ across regions and countries, such as country size, economic development, political stability, migrant networks, and cultural characteristics. It is important to note that the anticipated effects of climate change are just beginning to emerge, making it impossible to extrapolate from past trends.

At LISER, our focus is on developing structural models that project the long-term impacts of climate change on global inequality, extreme poverty, and human mobility. Our models differentiate between various types of movements, including those across countries, across regions, and within regions. What sets our approach apart is the ability to analyse the effects of climate change at a highly granular spatial level, specifically at the level of 5 by 5 km squared spatial cells.

Our findings confirm the well-established conclusion that rural regions in low-latitude areas will experience the most significant adverse impacts from climate change, thereby exacerbating global inequality of opportunity. Additionally, our research demonstrates that climate change will result in both forced and voluntary movements, potentially leading to millions of climate migrants throughout the 21st century. Depending on the scenario, an estimated 210 to 320 million people may be compelled to relocate due to climate change. However, the majority of these movements will likely occur within national borders. For individuals originating from the world's poorest regions, long-distance migration to richer destinations is a costly adaptation strategy. Hence, our findings suggest that large-scale international flows of climate refugees are improbable, unless extreme scenarios involving persistent and widespread conflicts over resources such as water or staple food arise.

Moderate migration responses to climate change imply that many will be trapped in impoverished and unstable regions, leading to significant increases in extreme poverty. While the media and political discourse often paint a gloomy picture of mass climate migration, our conclusion diverges from this narrative. Instead, we assert that the true threat lies in climate-induced poverty, which affects us all.

CLIMATE involves Michal Burzynski and Frédéric Docquier. In this project, LISER partners with scholars from Columbia University, the University of Western Australia and the World Bank.

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