Sustainability Issue: Global Warming
Migrants typically end up in cities in their target country, increasing the thermal pressure in those cities. If glocal warming is caused by human activity, then this activity will add to those human activities.
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Population Movement Impact
Migration typically take place from poorer countries to richer countries, war torn countries or countries that cannot support their population`s resource demands. This makes the source of the migrants more sparsely populated but increases the population of the target countries. Poorer countries have a much smaller resource demand per person than rich countries and this means that the migration from poor to rich countries increases the resource demands per person overall.