mass migration & population
As a result of population growth, humanity must produce more food in the next four decades than we have in the last 8,000 years combined. [30] [31]
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There are expected to be between 25 million and as many as a billion or more climate refugees by 2050. To put that in perspective, in 2019 there were 272 million international migrants. [32] The number has been increasing quicker than expected, and is up from 173 million in 2000. [33]
“Plausible” internal climate migration totals by 2050 across Sub-Saharan Africa, South Asia and Latin America under three scenarios. According to the Intergovernmental Panel on Climate Change (IPCC) Fifth Assessment Report under the lower emissions scenario, temperatures are likely to peak at 0.4°–1.6°C above baseline levels by 2050 and then stabilize. For the higher emissions scenarios, temperatures rise by 1.4°–2.6°C by 2050, and by 2.6°–4.8°C by 2100. [34]
An increase in international migration is a catalyst for geopolitical conflict. [35] The Pentagon has released reports detailing how this will lead to wars. [36] [37] The cause of the Syrian conflict can be traceable to climatic effects:
“Recent studies of the Syrian uprising have shown that growing water scarcity and frequent droughts, coupled with poor water management, led to multiyear crop failures, economic deterioration and consequently mass migration of rural families to urban areas. Rapid growing population, overcrowding, unemployment and increased inequality put pressure on urban centers and finally contributed to the breakout of political unrest.” [38] [39]
There are already geopolitical crises developing, such as between Pakistan and India over water rights. [40]
Spatial distribution of the direct and indirect effects of SLR (sea level rise) on human migration. The top panel shows all counties that experience flooding under 1.8m of SLR by 2100 in blue and colors the remaining counties based on the number of additional incoming migrants per county that there are in the SLR scenario over the baseline. [47]
Mexican farmers seized control of a dam in 2020 to prevent water payments to the United States. [41]
Impacts of SLR (sea level rise) due to flooding and human migration for a range of SLR scenarios. We say that a county is indirectly affected by SLR if the difference between the number of incoming migrants to the county in the SLR scenario and the number of incoming migrants in the baseline scenario, i.e. the number of extra migrants in the SLR scenario, is greater than some percentage, d, of that county’s population. In the top panel we show the spatial distribution of counties that are considered indirectly affected at different threshold values of d for the 1.8m SLR case in the southeast portion of the United States. In the bottom panel we show the number of people that are directly and indirectly affected under the same threshold values of d for the entire United States. For both plots we show aggregate impacts for five different values of d: 0.5%, 1%, 3%, 6%, and 9%. [47]
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There will be a rise in the use of concentration camps, as well as a resurgence of fascism and authoritarianism as a means of attempting to maintain control. This can already be seen today, for example China’s draconian camps for the Uighurs, and in the United States the camps along the southern border. [42]
Far-right groups have been surging around the world. [43] [44] [45]
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"In theory, demographic disparities between states with shrinking working age populations and those with a growing surplus of workers offer a potential win-win scenario. States with aging workforces will need workers (IOM 2017, 59; Kerwin and Warren 2017, 305-307), and working age persons in developing states will need work. However, shrinking native populations, coupled with rising levels of immigration, have led to a fear of racial and cultural displacement in many states, rising nationalism, and the vilification of immigrants. As a result, this dynamic may not lead to mutually advantageous policies. Tables 2 and 3 list the nations respectively whose populations will diminish (many developed states) and grow significantly (mostly African states) by 2050. Many of the developed states are in the throes of intense xenophobia and anti-immigrant sentiment, a trend that seems on the rise." [46]
Predicted changes to asylum applications under uniform climate change scenarios. We used 1000 samples drawn from the joint distribution of the model parameters to repeatedly predict the change in the percentage of total asylum applications filed in the EU. The solid red line shows the predicted change in percent, whereas the shaded areas illustrate the 90% and 99% confidence intervals. The blue line (right y axis) indicates the probability that asylum applications increase. [68]
The number of asylum seekers has been linked to the change in average temperature. [68]
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Pointing out the shortcomings of the previous study's methodology, other studies note that asylum seeking will not simply increase everywhere just as result of higher temperatures. Migratory outflow will occur most from countries experiencing local political instability or unrest. Policies that mitigate the effects of climate change hold the potential to reduce the likelihood of conflict and thus the prevalence of international migration. [36]