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Sustainability indicators

IB Environmental Systems and Societies • Unit 1

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Sustainable development

Sustainable development means improving people’s lives today while making sure future generations can also meet their needs.

Development is not just about money — it is about people, fairness, and Earth’s limits.

Development and GDP

For a long time, development was measured using GDP per capita, which shows the average income per person in a country.

  • Higher GDP often means better access to food, healthcare, and education
  • Higher incomes can improve living standards, especially in low-income countries
  • Economic growth can create a positive feedback loop: growth → better services → more growth
GDP does NOT show inequality, pollution, or damage to the environment.

Why GDP alone is not enough

  • Rising GDP does not always improve life for everyone
  • Much economic growth benefits the richest people
  • Rapid growth increases resource use and pollution
  • GDP ignores environmental damage and ecosystem limits
A country can be rich but still unsustainable.

Sustainable development indicators

To measure sustainable development properly, we use indicators. An indicator measures one specific part of human or environmental well-being.

  • Indicators measure health, income, inequality, pollution, population, and climate
  • Indicators can be used at local, national, or global scales
  • No single indicator gives the full picture

Examples of single indicators

  • GDP per capita → shows average income
  • Gini coefficient → shows income inequality (lower = more equal)
  • PM2.5 → measures air pollution (lower = cleaner air)
  • Extinctions per million species years → shows biodiversity loss
  • Natural increase rate (NIR) → shows population change
  • Average global temperature → shows climate change
For most environmental indicators, lower values are better.

Composite indicators

Composite indicators combine several indicators into one score to give a wider view of development.

  • Composite indicators use index numbers
  • They help compare countries more fairly
  • They include social and economic factors, not just money

Human Development Index (HDI)

  • Health → life expectancy
  • Education → years of schooling
  • Standard of living → income per person

HDI values range from 0 to 1. Higher values mean higher human development.


Planetary pressures–adjusted HDI (PHDI)

The PHDI adjusts the HDI by considering environmental pressure caused by development.

  • Includes carbon dioxide emissions per person
  • Includes material footprint per person
  • Shows whether development is achieved at the cost of the environment
High human development is not sustainable if it causes high environmental damage.

In exams, explain why multiple indicators are needed — GDP alone does not measure sustainability.

Key Terms

Biocapacity
The capacity of ecosystems to produce biological materials and absorb waste generated by humans.
Ecological deficit
When a population's ecological footprint exceeds the biocapacity of the area available to that population.
Economic indicator
A measure of economic performance, such as GDP, employment rates, or income distribution.
Environmental indicator
A measure of environmental quality, such as air quality, water quality, or biodiversity levels.
Social indicator
A measure of social well-being, such as education levels, health outcomes, or quality of life.
Sustainability indicator
A measurable quantity used to assess progress toward sustainable development.

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