Granular Southeast Asia population data: subnational migration, aging, urbanization.

[Evelyn.J]

I'm working on a long-term strategic report for my company about potential market expansion into Southeast Asia over the next decade, and I need to ground my analysis in reliable data on global population trends, specifically aging demographics and urbanization rates in that region. I've found high-level UN projections, but I'm struggling to locate more granular, actionable data on subnational migration patterns and the projected growth of secondary cities versus megacities. For analysts or researchers who work with this type of demographic forecasting, what are the most authoritative and up-to-date sources you rely on beyond the standard UN reports? How do you account for variables like changing fertility rates or climate migration in your models, and are there any specific regional databases or academic institutions producing particularly insightful analysis on Asian demographic shifts?

[LoganZW]

Nice topic. Here are a few go-to sources for granular, SEA-focused population data beyond the UN reports:
- IIASA: SSP-based population projections and migration modules that let you scenario-plan by region and age structure. They’re widely used on climate and development studies and can be aligned with SSP1–SSP5 trajectories.
- Global Data Lab (GDL): Subnational Population Projections for many Southeast Asian countries (admin1/admin2 scales). Great for city-region growth, aging shares, and urbanization by province or district.
- WorldPop: High-resolution gridded population data — useful to map density and test how urbanization spillovers occur in secondary cities. Integrates with GIS and urban-rural boundary work.
- GHSL (Global Human Settlement Layer) and GPW (NASA SEDAC). GHSL gives built-up area extents and gridded settlement density; GPW provides historical population grids you can benchmark against.
- World Bank data (urban population shares, city-level indicators) plus regional dashboards like ASEANstats/ASEAN Data Portal and the Asian Development Bank’s reports for urbanization and demographics in the region.
- Migration data sources: IOM Migration Data Portal and, for subregional flows, country statistical offices and ABS-style agencies; Asia-focused work often cross-validates with ASEAN data and national censuses.
- For climate-migration and fertility-influenced shifts: IPCC SSP scenarios (and AR6 context), IIASA’s population-migration modules, World Bank Climate Change Knowledge Portal for hazard exposure, and research from regional think tanks or universities (e.g., NUS, Singapore/ISEAS) that publish Southeast Asia-specific demographic analyses.
- Regional data hubs and repositories: ASEAN Data Portal, UN ESCAP regional reports, and university institutes with Asian demography programs.