Mapping Three Decades of Human Migration, a project joining Luxembourg and Laxenburg

Just south of Vienna, in the grounds of the historic Schloss Laxenburg, sits the International Institute for Applied Systems Analysis (IIASA), a place where researchers from across the world gather around problems too large for any single discipline or country. During my Short-Term Scientific Mission in July 2026, I had the privilege of joining Dr Roman Hoffmann and his group to advance an ambitious joint project between LISER and IIASA: building a unique global database of migration movements across administrative units, broken down by socio-demographic characteristics, for the three decades from 1990 to 2020 to support forward-looking climate-migration modelling.

The heart of the visit was turning a broad ambition into a concrete plan, starting with input data. We worked carefully through the inputs that will feed the machine-learning algorithm we plan to use to impute missing data points: detailed migration figures from national censuses (roughly 80% of the universe we need, already collected and harmonised by the LISER team), big-data signals from Facebook and LinkedIn, and additional covariates from global surveys such as DHS and Gallup. The IIASA and Gent teams' deep experience with Gallup data proved especially valuable, allowing us to construct a rich set of "push" and "pull" factors, including bilateral measures of people's willingness to move and their perceptions of the social, political and economic environment around them.

Beyond the immediate project, the visit laid the foundations for a lasting partnership between LISER and IIASA, grounded in shared interests in climate migration and in the complementary strengths of the two groups. These imputed data are a key input for calibrating LISER's CliC:ME MORE model (Climate Change: Migration and Economics - Model Revision), which will be the central joint endeavour of our teams going forward. To continue the work, I will return to IIASA in August 2027 - a visit that will coincide with a LISER PhD student joining IIASA's Young Scientists Summer Program, and that we hope will sharpen the policy-oriented goals of our collaboration.

I am very grateful to Dr Roman Hoffmann and the IIASA team for their generous hospitality and expertise, and to the EU COST Action CROSS-CASCADE for making this Short-Term Scientific Mission possible. I am confident the investment will prove a valuable return - for the Action, for our migration-modelling community, and for the wider scientific community.