Does the world seem crowded?
In some places, there seem to be people everywhere. Times Square in New York City is definitely one of those places. In other places, there are hardly any people at all. Does that mean that the world is not overpopulated? Is space all that people need?
Growth Rates Around the World
With ample food, better health, and easier work, people live longer. Children are much more likely to reach adulthood and have their own children. In many countries, death rates have gone down dramatically, but birth rates remain high. This means that the population is growing. Pictured below is the growth rates of human populations all over the world ( Figure below ).
World population growth rates. Is the population growing faster in the wealthiest countries or the poorest countries?
Human ingenuity has allowed the population to continue to grow. We’ve increased Earth's carrying capacity for humans by our genius. We grow crops, trade for needed materials, and design ways to exploit resources that are difficult to get at, such as groundwater. We use long-buried ancient organisms for fuel. We have broken the rules for biological populations.
Of course, there's a flip side to this. For the population to continue to grow, more advances in agriculture will be needed. The best lands are already in use. Most rivers that can be dammed, have been dammed. In many aquifers, groundwater is not replenished on the time frame needed. Fossil fuels too are limited. Obtaining fossil fuels or developing new power sources will be more costly.
Future Population Growth
The rate of increase of the growth rate of the human population is decreasing ( Figure below ). The population may stop growing by the mid 2000s. Some scientists think that the human population will peak at about 9 billion people. What will need to change for the population to stop growing then?
Try to locate on this graph Earth's carrying capacity for humans. Do you think this projection is very accurate or just a guess?
- carrying capacity : Number of individuals of a given species a particular environment can support.
- Humans have exceeded the carrying capacity of Earth for humans by their ingenuity.
- The rate of population increase is starting to decline. The population is still exploding though.
- The growth rate is higher in less developed nations.
Use the resource below to answer the questions that follow.
- Can the Earth Cope? at http://www.youtube.com/watch?v=_zHcX9gGCHc (3:04)
- How many people will Earth need to support by 2050?
- Where will most of the population growth occur?
- What countries' population will shrink?
- What country's population will triple?
- What kept our population in check in the past?
- How has human population exceeded Earth's natural carrying capacity for humans?
- Where is the human population growing the most? Where is it growing the least or not growing?
- Why is the rate of population increase now decreasing?