Human Population Growth Curve (DP IB Environmental Systems & Societies (ESS)): Revision Note

Human Population Growth Curve

• Population change rates vary with time

• The global human population grew very slowly until 18th century

  • From 10,000 BCE to 1700 CE the average growth rate was just 0.04% per year

• There has been exponential growth in the global human population since the mid 18th century

  • The global human population reached 8 billion in November 2022

• Despite the growth rate falling, the world population is projected to continue to grow until approximately 2100 when it could reach more than 11 billion

World population total and growth rate, 1750-2015 (with projections until 2100)

• Population change rates also vary over space

• Countries that went through Industrial Revolutions in the 18th and 19th centuries experienced rapid population growth

  • Today those countries are developed and their growth rates have fallen

  • In some cases, they have fallen so much that their total populations are in decline (e.g. Japan)

• The fastest population growth today occurs in developing countries that are rapidly industrialising

Global pattern of population growth rate (2021)

Increased Stress on Earth Systems

• As the human population grows, there is an increased demand for natural resources such as food, water, and energy, putting stress on ecosystems and depleting these resources

• The expansion of urban areas and infrastructure to accommodate the growing population leads to habitat destruction and fragmentation, affecting biodiversity and ecosystem functioning

• Increased consumption patterns and production of goods result in higher levels of waste generation and pollution, further straining environmental systems and contributing to climate change

• Growing population density in certain regions leads to increased pressure on land and can lead to issues such as deforestation, soil degradation, and loss of agricultural productivity

• The demand for freshwater increases with population growth, leading to overexploitation of water sources, depletion of aquifers, and potential water scarcity in some regions

• The increase in human activities, such as industrialisation and transportation, contributes to air and water pollution, greenhouse gas emissions, and overall environmental degradation

• The need for more housing, infrastructure, and agricultural land often leads to encroachment on natural habitats, resulting in the displacement and extinction of wildlife species

• The cumulative impact of human population growth on Earth's systems has implications for the long-term sustainability of resources, the resilience of ecosystems, and the overall health and well-being of both humans and the planet