Are there any data sources available, preferably freely (but not necessarily), which show population density without regard to country or constituency boundaries of any sort?
I'd like to analyze a map which shows the human concentration as accurately as possible, without "blurring" it by country or other similarly large areas, and instead using a grid of some sort.
One of the best gridded data sets is CIESIN's Gridded Population.
See http://sedac.ciesin.columbia.edu/gpw/aboutus.jsp#aboutTable for more details. The best resolution is 30 Arc seconds.
LandScan might be another alternative.
The dataset has 20,880 rows and 43,200 columns covering North 84 degrees to South 90 degrees and West 180 degrees to East 180 degrees.
The dataset has a spatial resolution of 30 arc-seconds and is output in a geographical coordinate system - World Geodetic System (WGS) 84 datum. The 30 arc-second cell, or 0.008333333 decimal degrees, represents approximately 1 km2 near the equator.
More info in documentation.
