1) Where is the world's population distributed?
The world's population is distributed all over the world, but large amounts of people come from Asia and Europe.
- Population Concentrations
- East Asia
- 1/5 of all the people on earth live in East Asia.
- Countries in East Asia include China, Japan, Korea, and Taiwan.
- 5/6 of East Asia's population comes from China, which is the highest populated country on earth.
- China's people mainly live around the Pacific ocean and the Huang and Yangtze rivers.
- 2/3 of China's people live in rural areas and are farmers.
- In Japan and South Korea, people cluster around urban areas and work at industrial jobs.
- The areas in which people live in Japan and South Korea cover less than 3% of their combined land area. In other words, they have low arithmetic density.
- South Asia
- Another 1/5 of the world's people live in this region, which consists of India, Pakistan, Bangladesh, and Sri Lanka.
- The main cluster of people in this area live along a 1,500 kilometer strip from Lahore, Pakistan, to the Bay of Bengal in India.
- Many people live along the Indus and Ganges rivers.
- Most people living in this area are farmers living in rural places.
- Southeast Asia
- The world's 4th largest population cluster is in this area.
- Population mostly consists of people living on islands including Java, Sumatra, Borneo, Sulawesi, and the Philippines.
- Indonesia consists of 13,677 islands, including Java, and is the world's 4th most populated contry.
- This area has a high population density with people mainly living along the rivers and deltas of Indochina.
- A high percentage of people living in Southeast Asia are farmers in rural areas.
- The three Asian concentrations make up half of the planet's population, but only 10% of the planet's landmass.
- 1/9 of the world's people live in Europe.
- This region consists of many countries of various sizes.
- Unlike Asia, most of the people living in Europe live in cities. Less than 20% are farmers.
- European people do not produce enough food for themselves and have to import from many different parts of the world.
- Eastern North America
- The population cluster in this area is the largest in the Western Hemisphere and only makes up 2% of the earth's total population.
- A large cluster is from Boston to the Creat Lakes and Chicago.
- Most Americans live in cities. Less that 5% are farmers.
- Sparsely Populated Regions
- Dry Lands
- Earth is covered by almost 20% of dry lands, which are regions too dry for farming.
- The largest dry land region is the Sahara, Arabian, Thar, Takla Makan, and Gobi deserts.
- Austrailia is also a large dry land region.
- While people cannot do a great amount of farming in these regions, many people are moving to them because lots of oil reserves are found there.
- Wet Lands
- Most of these regions are located between the Tropic of Cancer and the Tropic of Capricorn.
- They usually receive at least 50 inches of rain per year, with some getting up to 90 inches.
- Like dry lands, farming is not suitable for these areas because the combination of rain and heat kills nutrients in the soil.
- Rain may fall consistantly all year or seasonally.
- Cold Lands
- Most of the area near the poles is covered in snow and ice, some places being permanently frozen.
- These areas are also unsuitable for farming because they do not receive lots of precipitation and there are no nutrients in ice.
- Few animals and humans occupy these areas due to the extreme cold.
- High Lands
- Few people live at high elevations.
- Mountains are a hard place to live because they are steep, snow covered, and sparsely settled.
- Some people, however, prefer to live at high elevations to get away from uncomfortably high temperatures. These areas include places like Mexico City, Mexico.
- Population Density
- Arithmetic Density
- This is the total number of people divided by the total land area.
- To find the arithmetic density of the United States you would take the population, which is 300 million, and divide it by the land area, 3.7 million miles. This shows that there are about 80 people per square mile in our country.
- Some areas can be broken down and have a much higher population density, like Manhatten which has a population density of about 68,000 people per square mile.
- Arithmetic density allows geographers to compare the number of people trying to live on a given piece of land in different parts of the world.
- Phyiological density
- The number of people supported by a unit area of arable land is the physiological density.
- The physiological density of the United States is 445 per square mile.
- Physiological density lets us see the relationship between size of a population and how many resources are available to those people.
- By comparing arithmetic and physioligical density, geographers can tell when a country has too many people to provide enough of its own resources for.
- Agricultural density
- This is the ratio of the number of farmers to the amount of arable land in a country.
- The United States has an extrememly low agricultural density, only 1 farmer per square kilometer.
- Agricultural density can depend on the efficiency of the agricultural system, meaning that if people in one country have a better way of farming than another country, their agricultural density will be lower.
2) Where has the world's population increased?
The world's population is currently growing at an increase of 1.2% eash year. This growth is mostly due to countries in the eastern hemisphere.
- Natural Increase
- Geographers measure population change through crude birth rate (CBR), crude death rate (CDR), and natural increase rate (NIR).
- CBR means that if 20 babies born a year in a country with 1,000 people then their CBR is 20.
- Comparable to CBR, CDR is the number of deaths per year per 1,000 people
- NIR is the percentage that a population grows per year. It is found by subtracting CDR from CBR.
- The world NIR from 2000-2010 is 1.2, meaning our global population is growing by 1.2% each year.
- This means we are adding about 80 million people each year. This number has fallen from that of 87 million in 1989 because of the global awareness of overpopulation.
- Doubling time is the number of years needed to double a population.
- With an NIR of 1.2% the world's population would double in 54 years.
- Where there are high CBRs, there are high NIRs.
- Geographers use total fertility rate (TFR) to measure the number of births in society.
- TFR is the number of kids a women will have during her child bearing years (15-49)
- The TFR for the world is 2.7 but exceeds 6 in many countries in Africa.
- In addition to CDR, life expectancy and infant mortality rate are two other ways to define mortality.
- Infant mortality rate (IMR) is the number of deaths of babies under 1 year of age compared to births per year. It is done in numbers, not percentage.
- The higher rates of IMR are in poorer countries, whereas the lower rate is in wealthier countries.
- The IMR reflects a country's health-care system.
- Life expectancy measures the average number of years a newborn infant can expect to live at current mortality levels. This is also higher in wealthier countries.
3) Why is population increasing at different rates in defferent countries?
There are many different reasons population grows at different rates. Some countries grow quickly because of traditions and religious reasons. Some are not growing because of lack of space and overpopulation.
- The Demographic Transition
- Stage1: Low Growth
- Most of humanity's history was spent in stage 1 of the demographic transition. CBRs and CDRs varied over the years. This made the NIR be about zero.
- Around 8,000 B.C. the population was about 5 million people. This number got up to 800 million by 1750 A.D. This was caused by the agricultural revolution, which was the time when humans started farming and stopped relying so much on hunting and gathering.
- Today, no countries remain in stage 1.
- Stage 2: High Growth
- The global population began to grow at 10 times its normal pace in 1750 AD. The NIR jumped from about .05% to .5%.
- Population went from half a million in 1750 to 5 million in 1800.
- Stage 2 is when the CDR plummets and the CBR stays about the same.
- The Industrial Revolution was a cause of countries entering stage 2 because it was a major improvement in technology which made manufacturing goods easier. New machines helped farmers work faster and allow for more people to be fed.
- The medical revolution helped African countries reach stage 2 because of advances in medicine and helping sick people get better.
- Stage 3: Moderate Growth
- Countries move into stage 3 when their CBR begins to drop sharply. The CDR continues to fall, but at a slower rate than in stage 2.
- This is also a result of people deciding to have fewer children.
- People in stage 3 countries most likely live in cities and work in offices and factories rather than on farms. Farmers like having large families because their children can work for them.
- Stage 4: Low Growth
- This stage is characterized by when a country's CBR declines to that of the CDR and the NIR approaches zero. This is also called zero population growth (ZPG).
- Most european countries have reached stage 4 because they have TFRs well below 2.1
- Countries that have reached stage 4 have gone in a cycle, just with higher populations.
- Population Pyramids
- A county's population can be displayed by age and gender on a bar graph.
- Males are on the left and females are on the right.
- This can show people what stage a country is in based on the percentage of people's age.
- Age Distribution
- Dependency ratio is the number of people that are too young or too old to work compared to people that can.
- These age groups can be broken up into 0-14, 15-64, and 65-plus.
- Young dependents outnumber old dependents 10 to 1
- Sex Ratio
- The number of males per 100 females in a population is the sex ratio.
- In Europe and North America the ratio of males to females is 95:100
- Countries in different stages of Demographic Transition
- Carpe Verde is in stage 2. It is located off the coast of west Africa and is a small island. The country moved from stage 1 to stage 2 in 1950. The CBR exceeded the CDR and this produced an NIR of a stage 2 country but Cape Verde remained in stage 1 because of famine which disrupted births, deaths, and natural increase.
- Chile is a stage 3 country. They are likely to take some time before entering stage 4. Chile went from being mainly a farming country to an industrial country, with more people working in shops and factories. Many Chileans still prefer to have large families, which is uncharacteristic of most stage 3 countries.
- Denmark is a stage 4 country. Since the 1970s, the CBR and CDR have been roughly the same. The country has reached ZPG, and population growth is almost entirley because of immigration.
- Demographic Transition and world population
- The demographic transition shows how world population is influenced. The rapid growth of the world is due to many countries that remain in stage 2 and stage 3. There are no remaining countries in stage 1 and few have reached stage 4.
4) Why might the world face an overpopulation problem?
The world might face problems with overpopulation because eventually we are going to run out of space. In Japan people are talking about how eventually Japan is going to be one giant cemetary and there will be no room for people to live.
- Malthus on Overpopulation
- Population growth vs. Food growth
- Malthus claimed that one day the food supply will be insufficient for the population. He believed that people would not be able to frovide enough food, and therefore, have a much higher death rate in the future. He suggested people use "moral restraint", or keeping the birth rate low, to help save the population.
- Debate over how to reduce natural increase
- One approach to lowering birth rates is by improving economic conditions. Wealthier communities have more money to spend on education a medicine.
- Another way would be the use of contraceptives. Family planning programs can rapidly reduce birth rates and save countries lots of money. Many countries, however, are against birth countrol for religious reasons. Both of these methods can be very effective though.