An important part of alarmist argumentation is that it will cause mass migration. So one can find claims that "the expected number of climate change refugees will be in the hundreds of millions during the lifetime of children already born".
Really? Let's consider what can be expected during the next 60 years:
The main area where climate change can do harm is agriculture. In a local worst case scenario, it could be imaginable that the whole agriculture of a whole region fails. All those working in agriculture and their families would have to migrate. So this will be rural population, and their first target would be the towns of their own country, given that the jobs in towns are much less dependent on the climate.
But such internal migration from villages to towns is nothing but urbanization, a process which happens independent of any climate change, during the whole time of industrialization. The industrialization as a whole has been good for the people, they became richer, and this happens or happened everywhere. It means, towns all over the world have the ability to integrate a lot of migrants from villages without serious problems.
But how many people can be successfully integrated into the towns in poor Third World countries?
Let's look at China. Rural population (% of total population) in China was 40.85 as of 2018. Its highest value over the past 58 years was 83.80 in 1960, while its lowest value was 40.85 in 2018. So, in less 58 years China's rural population came down from 83% to 40%, a decrease of 43%. During the next 60 years, a repetition of this is simply impossible because even if the whole rural population would become urban, these would not be enough to reach the 43% again.
So China would be able to integrate into its towns more than all of its rural population during the next 60 years - it has already done this.
Now, China may be an exceptional case. Let's see how it looks worldwide. We find 66.4% in 1960 coming down to 44.7% in 2018. This has not caused any large catastrophes. So the world was able to integrate in these 58 years 22% of its popolation into the towns. We can conclude that the world could afford to integrate during the next 60 years another 22% of its population into the towns. After this, it would be on the same level as the European Union (24% today).
Let's not forget that this ability to integrate rural population will be in fact even greater. First, because during the last 60 years the towns additionally had to handle a much larger general population growth. The speed of population growth decreases, and it is today mainly caused by the increase of expectancy of life, the number of newborn children is today already almost constant. Then, what matters for the ability of the urban popolation to integrate migrant is their number in relation to their own number.
Let's illustrate this considering India. The picture looks much less impressive than that for China. But let's see: Rural population (% of total population) in India was 65.97 as of 2018. Its highest value over the past 58 years was 82.08 in 1960, while its lowest value was 65.97 in 2018. So rural population was goin down by 16% during 58 years. One could think that this shows that India can afford, without problems, another 16% or the rural population during the next 60 years.
But now look at this from the point of view of the urban population. They were 18% in 1960. They have afforded to integrate 16% during the following 58 years, without causing serious problem. So, they have afforded to integrate almost the same number of people. Actually, urban population in India is 34%. If these 34% show the same ability of integration of rural migrants, they can succeed to integrate 32% of the whole population during the next 60 years. After this, the Indian rural population would be reduced to 34%, which is already below Central Europe and the Baltics (38% today).
Above we have started implicitly assuming the most pessimistic model - all the rural population depends on agriculture. This is far from the truth today.
There are those who don't depend on agriculture completely: Retirees, pensioners, people working in the internet from their home, people working in other branches like tourism. With the rise of the number of jobs one can do from home the number of people who prefer to do such jobs living in villages will rise too.
There are all those doing various services for the general rural population: Shops, medical services, teachers, transport, maintainance of the infrastructure, police and other government services and so on. Some of them would follow if the peasants go away. Others will remain, at least if there remain enough other people.
So the number of those who would migrate to towns if the agriculture fails completely lies somewhere between the number of those with jobs in agriculture and those who live in that area. This makes it interesting to look at the number of those actually working in agriculture.
Here we see a simple and clear picture: This number decreases with industrialization, it is minimal in the industrial nations, and it decreases also everywhere else with time:
And the percentage of those working in agriculture in industrial states is quite low, below 2% in countries like the US, UK, Canada, Germany, and below 5% in many other industrial states. One should not think this part is small because they don't produce much. Not at all. They produce just much more efficient than the poor subsistence farmers in many Third World countries, and they produce enough not only for their own population, but also for export.
This is important because what is accessible to the farmers in rich countries now will be accessible also to farmers in the Third World, at least if this is not prevented by politics. So, even in the Third World countries it will not last that long and less than 10% of the population will be sufficient in agriculture.
I often argue that for the world as a whole the averages are more important when what could happen locally, and that for estimates if all this is dangerous for mankind as a whole one has, first of all, look at these averages, and only after this one should care about the problems which arise at those places where things go much worse than in the average.
With larger temperatures and more precipitation in the average, the situation will become better for agriculture in this average. So, if somewhere land will be lost for agriculture, there will be other places where new arable, farmable land appears because more precipitation and higher temperatures the region is no longer to arid resp. to cold for agriculture, and in the sum there will remain more arable land for mankind.
But while even alarmists cannot deny that such regions with new arable land will appear (they restrict themselves to expectations that this land will remain unusable long time), their main objection is that such new land in a completely different country does not solve any problem in those countries which are not so happy, but heavily harmed by climate change. Part of the argument is that to use the new land would, then, require the migration of all those peasants from the old places they can no longer use to these new lands. The costs for such a migration would be very large, given that there are hundreds of millions of such subsistence farmers to be relocated, with a lot of investments in these new places. Moreover, such a relocation would create a lot of political problems.
In reality, what will happen is completely unproblematic. In those countries where we have yet subsistence farming, standard urbanization will drive these subsistence farmers into the towns anyway. But these will be their own towns in their own country. As we have seen above, an essential part of the urbanization process will happen anyway during the next 60 years, and in a hundred years urbanization ends almost automatically because the remaining rural population is in the range around 20%, with less than 5% of the working force working in agriculture - completely independent of any climate change. And we have seen that the towns in the Third World can afford this without serious catastrophes, simply because they have already done this.
And the other part of the problem is essentially non-existing. Indeed, most of the new arable land appears, naturally, in regions where it is now too cold or too arid (or both) for agriculture. Warming would create some territories in Russia, Canada, Alaska, Island, Tibet. If the warming becomes really serious, one can add after some time Greenland. But, once these lands were uninhabitable, almost nobody is living there now. So, to use these new lands for agriculture, some people have to migrate to these regions and live there. So far, ok.
The question is how many of them are sufficient. And here it matters that modern agriculture does not need a lot of human workforce:
In a situation where less than 2% of the working population are sufficient to produce food for the whole country there is no necessity for migration of a lot of people to the new arable lands to use them for agriculture. This job will be done by modern, efficient agrofirms, which have everything necessary for this. With those firms, the number of people travelling to these regions will remain small, as small as possible for doing the job.
Problems of type "poor subsistence farmers cannot afford the necessary investments" will be completely irrelevant for building modern agriculture on such new land.
In some aspects, the "problem" that the new land is completely unused and uninhabitated is also an advantage because the new structures are also unrestricted by the existent infrastructure and the existent inhabitants of this area. What they build anew will be optimal from the economic point of view given the most up to date technology. The investments itself may have to be large, but they will be efficient over a much longer period.
Whatever, a large scale migration to make use of the new arable land is certainly not necessary. The amount of migration which is necessary for this will be small, and the money necessary for this will be part of the investments of the agrofirms which start this business.
I recognize that the text above does not whine even a little bit about the fate of all those poor subsistence farmers going bankrupt because of climate change and having to migrate to survive this. So one can expect, as a reaction, the usual heartbreaking nonsense about evil capitalist neoliberals and so on. Just to clarify, I'm not a neoliberal, neoliberalism I reject as a variant of corporatism (the economic system of fascism). I'm much worse - I'm an anarcho-capitalist, thus, I support a completely unrestricted, really free market.
But the point I want to make here is another one: The issue discussed here is climate change alarmism vs. common sense. Alarmism predict the total catastrophe if we don't do something extraordinary. I claim here that there will be no such catastrophe. I don't sell here my own utopia, my claim is only that there will be no catastrophe, that there is no reason to panic, not that everything will be fine.
So my argumentation here is not that those poor subsistence farmers will have a happy life. All I say that their fate will not be worse than the fate of all those billions of subsistence farmers who have gone bankrupt during the whole history of urbanization. Their fate will be hard enough - their first place to live in the town will be some cheap sleeping place in a corrugated-iron hut in some slum, the first job something low paid and illegal, and so on. Nice? Certainly not. But certainly better than the catastrophe painted by alarmists.
And, if we look at the history, also better than remaining a subsistence farmer in the village. Some of those poor bankrupted Chinese farmers who have migrated to the towns thirty years ago starting as swagmen you may have seen last year as tourists in Paris. "From rags to riches" is today a Chinese story. But even if not, one can reasonably expect them in the (lower?) middle class, quite certainly without necessity to care about their subsistence. But this is a long term expectation, and not for everybody but only for the average. Some will end in prison, some dead from drugs or crime, many will remain poor forever. Such is life.
So even if one disagrees with what I think about unregulated free markets, and think that they lead, following Marx, to horrible exploitation of the proletariat, this is not the point relevant here. The question is if the result of climate change is catastrophic or not. If the fate of the poor subsistence farmer is going bankrupt and surviving in the slums of overpopulated Third World towns, this is not nice but also not catastrophic.
Are there other possibilities how climate change can lead to mass migration problems around the whole world?
A sea level rise gives less than 2 m increase during the next 60 years even in the worst case scenarios, an amount which can be easily handled with dikes where necessary. So, this can be safely ignored.
Will the part of the population living in towns have to migrate?
A simple question with a simple answer: No. Why would they have to migrate? If local agriculture fails because of the climate change, so what? They live in towns, thus, they are not peasants, they don't work in agriculture. They have jobs in the industry, trade, services, whatever - all this does not depend on the climate. If it becomes too hot during the day, they will do their jobs during the night. For food, there is a world market already today, and they deliver without problems also to towns located in deserts. In the worst case, food becomes more expensive worldwide - but this is nothing one can change much by migration to other countries, where the food follows the world prices too.
So the only imaginable reason for migration of urban population would be a complete collapse of the world market for foods. Of course, some alarmists will propose this as what has to be expected. So, one could consider this separately too. But for the purpose of this question, we will ignore this possibility and assume that there remains a world market for food, so that those who live in towns can access food from the world market for the usual prices. Once their jobs are not directly connected to agriculture, they will not be lost because of climate change even if local agriculture fails. So, they have no reason at all to emigrate.
Climate change possibly causes problems for agriculture, but not for the jobs in towns. So, even if the climate change leads to serious problems for agriculture in some regions, so serious that rural people will have to leave their villages, their first destination will be, without doubt, the towns of their own country.
As shown above, the Third World towns have the ability to solve such an internal migration problem, given that they have managed comparable internal migration in the past and actually manage this too.
In principle, this may be possible. But I have reasons to doubt. We can say that the poorest subsistence farmers will give up and go to the town if they can no longer survive. But these poorest farmers are those who have to give up first anyway. A speedup depends on farmers the fate of farmers who sell something to the local towns. If, because of bad consequences of climate change, they produce less things to sell, this may be compensated by rising prices. Some compensation comes also from the subsistence farmers who give up and leave their land for cheap.
But such a rise of prices would happen if the climate change would hit agriculture globally. And in the average this would even overcompensate the loss. Why? The peasants who sell something on the market will hardly eat much less if they produce less. They will sell less. So the reduction of the amount of food on the market is greater than the reduction of their production. Say, a peasant usually eats 40% and sells 60% of his production. Now climate change reduces the production by 50%. The peasant will eat now less, say, 30% of the usual amount. What remains for the market are only 20% of the usual amount. That means, what is offered on the market is less than 1/2, it is only 1/3. Such a heavier reduction of the supply will increase the prices even more than simply a 50% reduction. So what one can expect is that the rising prices even overcompensate the losses.
Such effects are not pure speculation but well-known simple facts. If food becomes rare, the peasants become rich.
With a functioning world market for food, this effect will be reduced. There will be other regions, and many of them will even profit from climate change (given that warming, more CO2 and more precipitation are positive for plant growth, and this is what is predicted in the average). Nonetheless, the reduction of this effect will never be complete, simply because food produced elsewhere is burdened with additional costs for transport. So, to find out the final result is far from easy.
But let's consider some extreme scenarios. This is usually helpful to expect the possible range of consequences.
In the alarmist scenario, there are no good news from climate change in principle. So, the agricultural production goes down everywhere. Local differences are only about the degree of this loss.
In this case, the world market will be unable to prevent a serious rise of the market prices for food. And the predictable consequence is peasants will be fine. And, instead of being accelerated, the urbanization will decrease. It may even stop and go reverse, if no food is sold in the towns.
Ok, this header is a joke. I mean the prediction about the average of CO2, temperature and precipitation (all increasing) essentially predicts predicts the average outcome: Once all three elements favor plant growth, there will be, in the average, more plant growth too. It is clear that this is not a mathematical theorem, one can easily construct scenarios where all three rise in the average, but not necessarily locally, and all this conspires in such a way that plant growth is reduced almost everywhere. But common sense would ask for arguments that such conspiracies are plausible.
Whatever, in this case there would be a majority of places where food production becomes even easier. And, in the average, which defines the market price, the local decrease in production would be compensated by an increase in the worldwide production and lower world market prices. So, the local peasants cannot get higher prices because the world market will deliver cheap food.
In this case, there would be indeed an increase in bankrupties of local farmers, and urbanization would be enhanced. But in this case the decrease of the local food production would not be dangerous for the population of the towns, inclusive the newcomers, because the food prices remain low. So even in this case, the local towns could handle the local immigration problem.