International population migration is a movement of people across national borders. Citizens who enter the country are called immigrants who travel outside the state - emigrants.
Population migration is classified into several types.
So, the movement of people crossing the borders of states can be permanent (untimely) in nature. In this case, citizens move for permanent residence in the host country.
There is a temporary migration of the population. Stay in the country in this case, as a rule, is limited to a period of one to six years (due to the professional, family, age and sex characteristics of those entering, and also due to the continued dependence on the state of departure). Such migrants in international statistics are called “temporary contract workers”, “long-term immigrants and emigrants” or “permanent migrant workers”.
Short-term entry (within one year) is called seasonal. As a rule, migrants in this case enter the state to work in seasonal economic sectors (for example, in services, agriculture).
A variation of the seasonal movement of citizens is nomadism. This population migration is mainly distributed in the Middle East and West Africa. As a kind of seasonal movement, there is a pilgrimage to holy places.
Pendulum population migration (border, shuttle) is usually the daily (in rare cases, weekly) movement of the population across the border and back. Citizens who enter the country in such a way for work are called “working” frontaliers. This type of migration has become quite common in North America and Western Europe. For example, tens of thousands of citizens cross the US-Canada border daily.
Of particular note is such a variation in population migration as illegal. Underground citizens move to other countries in search of work. For example, more than a million people cross the US border from Mexico annually. Illegal migrants are also called those who entered the country legally (as tourists or by invitation), but subsequently got an illegal job in the host state.
The number of clandestine migrants has grown significantly since 1970. Accurately determining their number is almost impossible. For example, in the USA the number of clandestine emigrants ranges from two to fifteen million, in Europe - from 1.3 to 5 million, in Japan - from three hundred thousand to one million people.
The reasons for population migration in such cases are related to political, environmental and economic conditions. Mostly, clandestine migrants are a fairly disenfranchised and cheap labor force for entrepreneurs.
Forced border crossings are also associated with the environmental and political situation in the country of departure. This population movement became apparent in the 1980s and 90s. During this period, the migration of citizens has acquired enormous proportions. This, in turn, entailed many problems. Forced resettlement then acquired a global character and affected many countries of the world. Thus, according to statistics, about 87% of refugees settled in developing countries. By the 1990s, the number of internally displaced persons who entered economically developed countries on short-term visas and remained asylum-seekers rose sharply.
A special type of migration of citizens is an episodic movement of the population. In this case, border crossing is connected exclusively with international tourism or other trips abroad.