This study approached migration-related problems from a global perspective. The inter- connected nature of migration means that migration problems accumulate and intensify throughout the world. To capture these effects, a data-rich model component was devel- oped for global migration dynamics.
To that extent, this study has developed the following innovations on a methodological level: a technique to comprehensively implement spatial phenomena into System Dynam- ics, a method to implement multi-scale System Dynamics through subscript mapping, and a semi-automated data acquisition process to obtain and structure a great variety of data sets on a country level. The nature of the developed model component is generic. That is, the component is scalable, and resolution-independent, as it is initialized through exter- nal databases. Therefore, a significant part of this study comprised the development of a semiautomated data acquisition process. The model component was then connected to a root-causes model component to analyze future migration scenarios on a global scale. It was found that migration is expected to increase in line with population growth.
Policies were implemented and tested on a global, regional, and national scale. In the global policy case, the location of additional shelter and coping capabilities was found to greatly influence migration dynamics across the world. Additional shelters in low-income countries greatly reduced the number of migrants traveling towards the more wealthy coun- tries. The regional policy—closure of the European borders when a certain threshold is reached—had significant effects on the countries near the border, but failed to significantly improve the situation in the rest of Europe. This can be attributed to the delayed effects of such policies in these countries. National policies were tested for the Netherlands. Effects of these policies were insignificant, due to the inertia of the migration system. The number of migrants in Germany—a neighboring country—did not significantly change, and even the effect on the number of migrants in the Netherlands was negligible.
Therefore, the first advice from this study towards policy-makers is that it might be more effective to address the root causes of migration, rather than just mitigating its detrimental effects. In addition, the inertia of the migration system requires globally aligned, large-scale policy implementation to prevent and mitigate migration-related problems. The delay in these policies should not be neglected, so it is important to identify potential problems as early as possible and take appropriate action.