What is World Population?
In demographics, the world population is the total number of humans currently living and was estimated to have reached 7,800,000,000 people as of March 2020. It took over 2 million years of human prehistory and history for the world’s population to reach 1 billion and only 200 years more to grow to 7 billion.
The world population has experienced continuous growth following the Great Famine of 1315–1317 and the end of the Black Death in 1350 when it was near 370 million.
The highest global population growth rates, with increases of over 1.8% per year, occurred between 1955 and 1975 – peaking at 2.1% between 1965 and 1970.
The growth rate declined to 1.2% between 2010 and 2015 and is projected to decline further in the course of the 21st century. The global population is still increasing, but there is significant uncertainty about its long-term trajectory due to changing rates of fertility and mortality.
The UN Department of Economics and Social Affairs projects between 9–10 billion people by 2050, and gives an 80% confidence interval of 10–12 billion by the end of the 21st century.
Other demographers predict that the world population will begin to decline in the second half of the 21st century. A popular estimate for the sustainable population of earth is 8 billion people as of 2012. With the world population at 7.8 billion people as of March 2020 and typical projections of population growth, Earth will be in a state of human overpopulation by 2050 or sooner.
Population Distribution Factors
Population distribution is a term that is used to describe how people are spread across a specific area. In other words, population distribution shows where people live.
Population distribution can be measured across the entire world or a smaller region within a country or continent. Population density is typically expressed as the number of persons per square kilometre (/km2) or square mile (mi2).
Following are geographical factors:
Availability of Water
Water is the most important factor in life. So, people prefer to live in areas where freshwater is easily available. Water is used for drinking, bathing and cooking – and also for cattle, crops, industries and navigation. It is because of this that river valleys are among the most densely populated areas of the world.
People prefer living on flat plains and gentle slopes. This is because such areas are favourable for the production of crops and to build roads and industries. The mountainous and hilly areas hinder the development of transport networks and hence initially do not favour agricultural and industrial development.
So, these areas tend to be less populated. The Ganga plains are among the most densely populated areas of the world while the mountains zones in the Himalayas are scarcely populated.
An extreme climate such as very hot or cold deserts is uncomfortable for human habitation. Areas with a comfortable climate, where there is not much seasonal variation attract more people. Areas with very heavy rainfall or extreme and harsh climates have low populations.
Mediterranean regions were inhabited from early periods in history due to their pleasant climate.
Fertile soils are important for agricultural and allied activities. Therefore, areas that have fertile loamy soils have more people living on them as these can support intensive agriculture. Can you name some areas in India which are thinly populated due to poor soils?
These are economic factors given below:
Areas with mineral deposits attract industries. Mining and industrial activities generate employment. So, skilled and semi-skilled workers move to these areas and make them densely populated. Katanga Zambia copper belt in Africa is one such good example.
Cities offer better employment opportunities, educational and medical facilities, better means of transport and communication. Good civic amenities and the attraction of city life draw people to the cities. It leads to rural to urban migration and cities grow in size. Megacities of the world continue to attract a large number of migrants every year.
Industrial belts provide job opportunities and attract large numbers of people. These include not just factory workers but also transport operators, shopkeepers, bank employees, doctors, teachers and other service providers. The Kobe-Osaka region of Japan is thickly populated because of the presence of a number of industries.
Some places attract more people because they have religious or cultural significance. In the same way – people tend to move away from places where there is social and political unrest. Many times governments offer incentives to people to live in sparsely populated areas or move away from overcrowded places. Can you think of some examples from your region?