Human Population Growth

The Carrying Capacity of Earth? The carrying capacity of Earth is not known and at present it is impossible to determine when the human population will stop growing

Demography The study of human population growth trends Looking at past trends helps in determining future trends Demographers study the birth rates & death rates (which determines growth), fertility (factor of birth rate), and age structures of population Age structure visualized by graphs; proportions of populations at different ages

Human Pop Growth Tends to increase, just like other organisms – however – the rate of increase has changed dramatically

Growth over the last 2000 years… http://www.globalchange.umich.edu/globalchange2/current/lectures/human_pop/human_pop.html

By the numbers… 1960 3 billion 1804 1 billion 1999 6 billion World Population Growth Year 1 200 million 1000 275 million 1500 450 million 1650 500 million 1750 700 million 1804 1 billion 1850 1.2 billion 1900 1.6 billion 1927 2 billion 1950 2.55 billion

Largest Countries in the World 2050 2008 China - 1,330,044,544 India - 1,147,995,904 United States - 303,824,640 Indonesia - 237,512,352 Brazil - 196,342,592 Pakistan - 172,800,048 Bangladesh - 153,546,896 Nigeria - 146,255,312 Russia - 140,702,096 Japan - 127,288,416 India - 1,628,000,000 China - 1,437,000,000 United States - 420,000,000 Nigeria - 299,000,000 Pakistan - 295,000,000 Indonesia - 285,000,000 Brazil - 260,000,000 Bangladesh - 231,000,000 Democratic Republic of Congo - 183,000,000 Ethiopia - 145,000,000

Predictions of Future Population Growth Predicting how a population’s size may change… Begins with determining information about individuals in each of the population’s age classes Creating an age-structure graph…

Demographic Transition A dramatic change from high birth rates and high death rates to low birth rates and low death rates (slowly growing) The US, Europe, and Japan have completed this demographic transition Parts of South America, Asia, and Africa are in stage 2 of 3, where death rate is down but birth rate is still high

Interesting Tidbits.. The Ecological Footprint data suggest that 3 – 4 planets with the Earth’s bioproductive capacity would be required to support the current population at the consumption level of North Americans The ten countries which will contribute most to world population growth over the next 30 years are India, China, Pakistan, Nigeria, Ethiopia, Indonesia, United States of America, Bangladesh, Zaire, and Iran 171,000  517,000 density 1950-2050