New Data Source: Include new data source to cover blindspots of current Facebook data sets (population-density)

[mattigrthr]

Facebook doesn't offer its population data for some regions, e.g., due to quality issues in satellite imagery. To cover these current blindspots, we should include another data source.

@tjukanovt proposed a dataset by Kontur which combines the Facebook data with GHSL, OSM, and building footprints data on a 400 m resolution using H3 but truly globally. It can be found on HDX.

If it is a quick win, we could either include that dataset directly or write a pipeline for the GHSL data. It would be a decision based on features and dependency on an intermediary like Kontur. We're open to discussing this with you here, of course!