Arbeitsbereich

Migration und Mobilität

Auf einen Blick Projekte Publikationen Team

Projekt

Estimating Migration and Mobility after Environmental Hazards

Emilio Zagheni, Asli Ebru Sanlitürk, Daniela Perrotta, Risto Conte Keivabu; in Zusammenarbeit mit Monica Alexander (University of Toronto, Kanada), Kivan Polimis (University of Washington, Seattle, Vereinigte Staaten)

Ausführliche Beschreibung

The goal of this project is to leverage digital trace data to complement official statistics and surveys in order to monitor population movements after natural disasters, such as hurricanes, wildfires, or earthquakes. While demographic data collected from online sources contain known biases and issues of non-representativeness, they have the advantage of being available almost in real time. When combined with appropriate statistical corrections, these data provide a valuable resource for producing timely mobility estimates and advancing theories on migration and adaptive mobility in response to shocks.

This project draws on various sources of digital trace data, including mobile phone-derived mobility data, social media data collected via advertising platforms, and publicly released mobility datasets derived from social media platforms (e.g., Meta – Data for Good). In the context of natural disasters, these data make it possible to assess not only the scale of displacement, but also its demographic composition, at times when traditional data are often unavailable. These data further enable us to identify inequalities and structural gaps in mobility responses to sudden environmental shocks, and to investigate how displacement patterns may differ by sociodemographic characteristic and broader access to resources and opportunities.

In a particular case study, we examined short-term mobility responses to wildfires in Spain between 2022 and 2024. We used open mobility data published by the Spanish Ministry of Transport, Mobility and Urban Agenda (MITMA), which provide district-level estimates of hourly origin-destination mobility flows and overnight stays. We combined these data with wildfire exposure measures from the European Forest Fire Information System (EFFIS), a harmonized European database on wildfire events, and district-level income information. We examined how proximity to wildfires and associated air pollution affected short-term mobility by intensity of exposure and socioeconomic context. Our findings showed that, while mandatory evacuations resulted in displacement regardless of income level, voluntary mobility responses to wildfire risk and smoke exposure exhibited a clear socioeconomic gradient. Only the highest-income group exhibited a statistically significant decrease in overnight stays, indicating a greater propensity to relocate themselves in response to heightened risk of wildfire and particulate matter exposure, even in the absence of mandatory evacuations. These findings highlight the central role of policy in structuring adaptive mobility and socioeconomic disparities in wildfire response.

Overall, the project leverages digital trace data to measure changes in migration and mobility responses to environmental hazards. In particular, it examines variations by age, sex, and destination across environmental events, and it aims to advance our theoretical understanding of migration and mobility following sudden shocks, including the role of social networks, information diffusion, and multiple dimensions of distance.

Publikationen

Mason, M.; Noel, S.; Rosenquist Ohlsson, L.; Salim, Z.; Conte Keivabu, R.; Perrotta, D.; Şanlitürk, A. E.:

Unequal adaptation: socioeconomic stratification in short-term mobility responses to wildfire hazards in Spain

MPIDR Working Paper WP-2026-023. (2026)    

Alexander, M. J.; Polimis, K.; Zagheni, E.:

The impact of Hurricane Maria on out-migration from Puerto Rico: evidence from Facebook data

Population and Development Review 45:3, 617–630. (2019)