Population projections for US states under the Shared Socioeconomic Pathways based on global gridded population projections

We test alternative aggregation methods and geographic resolutions of the gridded population to derive the aggregate state-level projections for all 50 states (and Puerto Rico), for rural and urban areas. Results show that with high resolution gridded population data for the present population, the upscaling outcomes match reasonably well total population at the national and state levels. Comparison of the state-level projections aggregated from the grid cell level to explicit state projections from the US Census Bureau through 2030 show that results are reasonable for many states, but are much less reliable for states experiencing population dynamics differing from national overall patterns.

Results therefore also demonstrate the need for a new set of alternative, state-level population projections with consistent gridded outcomes.