Populated Regions of The World...

Here is a quite easy thought that might seem very obvious to implement, yet it cannot be better visualized: An interactive world map showing the population density for different user-defined values controlled by a slider bar. The map could be found here, and is developed by a postgraduate student. Similar population density data could be found in websites such as this.

What is interesting here is that the interactive animation shows the change by varying the number of people per squared kilometer. See the figure below for a snapshots for an increase every 100 people/Sqkm.

What could be analytically intriguing is that you can draw some very informative inferences regarding the influence of the geographical and topographical nature of different parts on earth on the population concentrations.

For example, with a population density of 5 people/Sqkm the harsh desserts (Sahara & Australian and US desserts), deep forests (Amazon), rough topography (Tibet) and deep snow continental areas (Siberia and Canada) could be easily noted on the highlighted map.

For 100 people/SqKm, the spacious life-style nature of the US makes it less "clusterous", where people would tend to have this tendency to spread out except for major cities such as New York, whereas the whole continent of South America seems to have totally faded-away! The south of the UK and central Europe (mainly Germany and the Netherlands) seem to have a high value at that level probably due to the concentration of jobs and the London-like atmosphere. On the other hand, China and India remain fully dark as might be expected.

Moving to the extreme of 500 people/SqKm, it can be easily noted that Cairo extends in many directions with a high value nearly all over the city, which demonstrates that many migration flows in the Egypt would tend to be directed towards the Capital, Cairo. The north of India and some areas in China seem to have the biggest values and the widest spread of the high population density in the world which might not come as a surprise! However, the concentration of these high values seem to be concentrated away from the ocean in India and near the ocean in China. Indonesia comes as a surprise as Jakarta comes as number 17 among the list of most density-populated cities in the world, whereas what is clear from the map is it is not only restricted to Jakarta, but the spread totally occupies the southern part of the islands (Semarang).