In a recent article, Nick Stockton comments on a study published in Science where “a team of geographers (from the Wittgenstein Centre for Demography and Global Human Capital in Vienna) used data snapshots to create a broad analysis of global migrations over 20 years”.
This kind of study is quite hard “because each country has its own methodology for collecting census data”.
We often see demographic mesurements shown in static graphics and tables that hardly give us a clear picture of how people are moving over a certain period of time. These circular migration plots (cfr. Circos, a software frequently used in genetics) allow to observe the flow of migration over a given time.