Population Dynamics
Natural Population Change = Birth Rate - Death Rate
Overall Population Change = Natural Population Change + Net Migration
Currently, the world's population is growing fast - though this has not always been the case.
1. Until the 1800s the world's population grew steadily but slowly for thousands of
years.
2. In 1820 the world's population reached one billion.
3. 150 years later, in the early 1970s, the world's population reached three billion.
4. In 1999, less than 30 years later, the population doubled to six billion.
5. The global rate of population growth is now very fast (rising by about one billion
every 15 years)
Population Increase
The population of any place changes over time. Three main causes of population change are
births, deaths and migration
- Improved medical care - vaccinations, hospitals, new drugs and scientific inventions
- Improved sanitation and water supply
- Improvements in food production (quantity & high nutrition value)
- Improved transport – moving food, doctors etc.
- Decrease in child mortality
Natural Population Change = Birth Rate - Death Rate
Overall Population Change = Natural Population Change + Net Migration
Currently, the world's population is growing fast - though this has not always been the case.
1. Until the 1800s the world's population grew steadily but slowly for thousands of
years.
2. In 1820 the world's population reached one billion.
3. 150 years later, in the early 1970s, the world's population reached three billion.
4. In 1999, less than 30 years later, the population doubled to six billion.
5. The global rate of population growth is now very fast (rising by about one billion
every 15 years)
Population Increase
The population of any place changes over time. Three main causes of population change are
births, deaths and migration
- Improved medical care - vaccinations, hospitals, new drugs and scientific inventions
- Improved sanitation and water supply
- Improvements in food production (quantity & high nutrition value)
- Improved transport – moving food, doctors etc.
- Decrease in child mortality
