In order to link environmental data with climate-induced migration, the researchers combine them with movement profiles derived from aggregated, anonymized mobile phone data. In this way, people’s mobility patterns become visible in the context of the physical environment. “These basic patterns are not necessarily linked to migration. They include regular seasonal movements, such as those of seasonal workers in agriculture, because certain crops are grown in specific locations and the workers go there.” Since the researchers collect very fine-grained data over long time series, they can, however, identify deviations in the patterns that indicate a migration movement. If, for instance, a natural disaster coincided in time and space with movement anomalies, a connection seems likely.
Lang’s project partners supplement the data with anonymized social media posts and cell phone data in order to gather evidence about the motives for migration. These data allow conclusions to be drawn as to whether the author of a post was actually fleeing and in what way migration processes are shaped by individual attitudes, socioeconomic resources, and public opinion. Additional sociological data are collected on-site through qualitative interviews. The interviews focus not only on individual motivations but also on household-level behavior, where local coping strategies play a significant role in the wake of a singular or recurring event (annual floods, moderate droughts, cyclones).
