Population Size, Fertility And Mortality, And Age Structures Essay

The world population of 7.2 billion in mid-2013 is projected to increase by almost one billion people within the next twelve years. It is projected to reach 8.1 billion in 2025, and to further increase to 9.6 billion in 2050 and 10.9 billion by 2100. This assumes a decline of fertility for countries where large families are still prevalent as well as a slight increase of fertility in several countries with fewer than two children per woman on average.

2,000 years ago the world, in terms of population, was only the size of the United States of America, 300 million people. Today, the world’s population is at seven billion and counting. If the population rose at a steady rate from year 0, we would’ve reached 1 billion people by about 210 A.D. This, however, was not the case. We reached 1 billion people in 1800 A.D, which means that there had to be very odd growth periods for the population as a whole REWORD ME. From 0 to 1000 A.D. the population only rose about 10 million people, “and well into the second millennium, [the population] grew less than 0.1 percent each year” [1]. However, from the year 1800, with 1 billion people worldwide, to 1930, the world gained another billion people. We then reached three billion people in 1960, five billion in 1987, and 7 billion in 2013. One can clearly see that once we entered the 19th century, the world’s population started growing like a 14 year old boy going through puberty; rapidly, and without any warning. One thing that can explain this growth is called the Demographic Transition.The Demographic Transition is a theory that explains the growth.

The 1800’s was the first time the population reached 1 billion. Today the Earth is at a grand population of 7.125 billion according to World Bank. Although, it wasn't always that way. There was two revolutions that changed the world's population forever.

As the human race continues to grow older the population starts to grow. Population growth is a change in the size of a population over time, depending on the balance of births and deaths over a period of time. For the world, population grows when the amount of births exceeds the amount of deaths. As shown in figure 1, the world’s population grew very slowly until about 1750 that is when the population growth started to increase rapidly. Figure 2 shows the growth of the global population from 1950 onwards, it also shows the projected population growth up to 2050. The global population is estimated to rise to approximately 9 billion people by 2050.

The demographic transition theory is a widespread explanation of the changing mold of humanity, fertility and increase rates as civilizations move from one demographic system to another. “The term was first coined by the American demographer Frank W. Notestein in the mid-twentieth century, but it has since been elaborated and expanded upon by many others” (The Demographic Transition, 2012). There are four stages of demographic transition.

During the cold war era the life expectancy grew by about 15 years, however in the 1980’s the world saw a decline in life expectancy especially in the USSR falling from 70 years down to 53 years old(C&C 1040). Along with this came an uncertainty for population growth in developed and underdeveloped countries. For example, in China Emperor Deng established a one child policy, in Iran and other Islam dominate countries governments were urging families to space out their conceptions(C&C 1041).

In this essay i will be writing about how the population all over the world is affected. By the end of the century japan's population is expected to shrink by half, with 1 out of every 3 people retired. Over the next fifty years europe is going to lose up to 63 million people. Russia will shrink almost 20%. Elders over 60, outnumber children over 4. The economic and social changes will be terrible. More children in developing countries are surviving than ever before. Today the largest generation of youth industry is entering their reproductive years. As global population declines from 6 to 9 billion, the social and environmental changes will be huge.

* According to demographers, what factors lead to a decline in the crude birth rates (CBR) and crude death rates (CDR) in the epidemiologic and fertility phases of the demographic transition? ·

While it may be observed that the exponential rate of growth is slowing, the world population is still growing rapidly. Perhaps the biggest concern is not the actual population increase but the distribution of the growth (Wilson, Population).

Between 1400 and 1700, the global residents rose slightly from 300 million to about 1,2 billion people but then this figure dropped marginally to just under 1 billion humans. After a decline of 300 million people, the number of this grew sharply by nearly 5 billion, to exactly 6 billion people worldwide at the end of the examined period.

There has been a demographic shift in the population of the world. With the increase in medical technology and a decline in fertility rates, older adults (60 years of age) are estimated to account for 2 billion of the world’s population by 2050 (Hokenstad & Roberts, 2011). To put this in perspective, in 2009, one in nine of the world’s population was older adults; by 2050, the population will shift to one in five older adults.

This talk connects to the key term of demographic transition because in order for the population of the world to cease growing

Population ageing is a major global demographic trend. As the life expectancy continues to increase, the proportion of elderly people rises simultaneously. For instance, the life expectancy in Japan was 79 years old (World Trade Organisation, 2014) in 1990, the number then raised to 84 years old (World Trade Organisation, 2014) in 2012 and accounted for 39% (World Bank Data, 2014) of the whole Japan population.

The population aging, in other words, the greying of the population is major concern all over the world. Many factors are leading to population aging, namely, unwillingness to marry, late marriage, fertility control, low birth rate and longer life span. All these factors are also related to developing status of the country. The more the country is developing, the more the factors have stronger effect on aging population and the age population problems of the country is more serious.

Demography is the study of the components of population variation and change. Death rate and birth rate are two determinants of population change. Theory of Demographic Transition is comparatively recent theory that has been accepted by several scholars throughout the world. This theory embraces the observation that all countries in the world go through different stages in the growth of population. A nation's economy and level of development is directly related to that nation's birth and death rates. Population history can be divided into different stages. Some of the scholars have divided it into three and some scholars have divided it into five stages. These stages or classifications demonstrate a