This map uses a power scale to scale each country’s area by its projected 2050 population, with SVG paths transformed around their geographic centroids. D3’s `geoNaturalEarth1` projection and `geoPath` draw the world, while `scalePow` and `scaleSqrt` determine the sizing. A hover tooltip reveals the country name and population, and a legend shows the color scale for data values. Population data comes from a UN CSV file, and countries missing 2050 data are rendered white with a “Missing data” tooltip.