The Square Density visualization was created by Garrett Dash Nelson, 2019.
Cells are 30 arc-second grid cells, which are approximately, but not exactly, one square kilometer.
Cities are treated as Census Bureau Combined Statistical Areas, buffered by 1 minute to capture coastline pixels.
Population data is attributable to: Center for International Earth Science Information Network - CIESIN - Columbia University. 2018. Gridded Population of the World, Version 4 (GPWv4): Population Count, Revision 11. Palisades, NY: NASA Socioeconomic Data and Applications Center (SEDAC). https://doi.org/10.7927/H4JW8BX5.
Inspired in part by Alasdair Rae’s work on global gridded population.