With an increase in the average annual temperature on Earth of 1 degree Celsius, at least a billion young people will be forced to adapt or migrate in order to stay in the climatic conditions that are best suited for agriculture, livestock and outdoor work. Scientists came to such conclusions on the basis of analysis covering the period of the last 6 thousand years. This is an important topic, because many guys during their ESK projects revise their views on the environment and become eco-activists. This topic is interesting to me and my project colleagues, and I decided to sort it out.
The climate of the Earth has changed throughout its history. Over the past 650 thousand years alone, the planet has survived six periods of glaciation and “thaws”. These slow but large-scale climate changes depend on many complex processes (you can read about them here, for example), but the main one is the oscillations of the earth's orbit, which are called Milankovitch cycles, which change the amount of sunlight reaching different regions of the planet .
However, the modern climate era is different from the previous ones. The current warming trend in Europe is of particular importance, as the temperature rises incredibly fast - starting in 1975 at a rate of about 0.15-0.20 degrees Celsius per decade. Since 1880, the average temperature of the Earth has increased by one degree Celsius. This is quite a lot: already now we are seeing an increase in the level of the world's oceans, a decrease in the area of the Earth’s ice cover and a greater number of extreme weather events - all this Meduza wrote in detail in the text, which contains the main questions about current warming.
The reasons for the current climate change are now well understood, but this cannot yet be said about its economic and social consequences, for example, about the scale of future forced migration. There are many independent estimates, but there is still no single universally accepted way to calculate the number of young people who will need to relocate from their homes as a result of warming.
For example, according to the International Center for the Study of Internal Migration (IDMC), as early as 2018, 17.2 million people were forced to leave their homes due to disasters that negatively affected their lives. The World Bank predicts that if European governments do not take serious measures to change the situation, by 2050 the number of internal climate young migrants in the three regions of the world will reach 143 million. Changes will affect the economy: a study conducted by McKinsey Global Institute shows that increasing the average annual temperature of the planet will affect the ability of workers, infrastructure, food and natural resources.
In the new work, an international group of anthropologists led by Martin Schaeffer proposed a new approach to calculating the scale of future migration - by searching for the “ecological niche” of the young man and analyzing how it will change with climate change.
Warming will shift the "ecological niche" of man and cause mass migration
When biologists talk about the ecological niche of animals and plants, we usually mean the totality of the necessary environmental factors in which one or another species lives. Including, of course, the climate is also taken into account. Thanks to their social and technological capabilities, young people have significantly expanded the boundaries of their “ecological niche” and are not as limited by environmental conditions as animals, but it’s impossible to say that we have become completely independent of the environment - and therefore the authors of the new work decided to determine where the most comfortable and productive living areas for humans are located and how climate change will affect them.
The study relied on a historical database compiled by Dutch environmentalists, which contains information about the population and agriculture on the entire planet for 12 thousand years. It presents all available data on cultivated crops, livestock distribution, gross domestic product, past and current average annual temperatures, rainfall, and other similar statistics. It is on the basis of these data that scientists have identified those zones that can be considered historically optimal habitat for humans.
As it turned out, for the past six millennia, most young people have lived in the same narrow climatic strip, where the average annual temperature is about 11-15 degrees Celsius. Current crop and livestock production is largely limited by the same conditions. Another "comfortable" temperature for mankind - from 20 to 25 degrees - dominates South Asia, which is under the influence of the Indian monsoons. This climate had the second highest peak in population density. Of course, some people live in colder and hotter regions - so far, humanity has settled from the north to the south pole. However, the population in all other areas, in addition to these two, is noticeably smaller, and the conditions of existence there are somewhat harsher.