How global migration patterns will evolve in the future

It's intriguing to think about future migration patterns. There are a couple of forces playing, each of them with a different, somewhat contradictory outcome, which makes any prediction on how it will eventually turn out painful:

• ecological migration: as more and more territories will suffer from drought and -likely- more severe weather conditions, new forms of migration will emerge -likely from the center to the North and/or South;
• economic migration: the form we now know -from poorer to richer countries-, will likely be supplemented by a now form: Western youngsters migrating to countries with higher growth (emerging countries) in search of better working conditions, more growth prospects or even -in term- better education;
• diaspora returning to country of origin... something now happening with Indian immigrants, but just imagine what this would lead to for China (if further democratization materializes, for instance).

...this would give a completely different picture than the current status, nicely shown in the graph of The Economist beneath...

(From The Economist) MORE Chinese people live outside mainland China than French people live in France, with some to be found in almost every country. Some 22m ethnic Indians are scattered across every continent. Diasporas have been a part of the world for millennia. But today their size (if migrants were a nation, they would be the world’s fifth-largest) and the ease of staying in touch with those at home are making them matter much more. No other social networks offer the same global reach—and shrewd firms are taking notice.