Sustainability Indicators (HL IB Environmental Systems & Societies (ESS))
Revision Note
Sustainability Indicators
Sustainability indicators are quantitative measures used to assess various aspects of sustainability
These indicators can be specific to biodiversity, pollution, human population, climate change and many other factors
Some well-known sustainability indicators include ecological footprints, carbon footprints and water footprints
Sustainability indicators can be applied across different scales, from local to global, to evaluate the environmental, social and economic dimensions of sustainability
For example, they can help us understand if something is environmentally friendly, socially fair and economically viable
Ecological footprints
An ecological footprint (EF) is a theoretical concept that acts as a valuable tool used to assess the environmental impact of human populations
It quantifies the area of land and water required to support a specific population at a particular standard of living
An EF is measured in global hectares (gha) per capita (i.e. hectares per person) per unit time
The ecological footprint provides a comprehensive measure of the demands that human populations place on the environment
It takes into account the resources consumed by individuals, such as food, energy, water and materials, as well as the waste generated and the ecosystem services required to absorb that waste
By considering these factors, ecological footprints help to evaluate the sustainability of human activities
EFs can be used to compare the sustainability of different lifestyles, businesses and even whole countries
If the EF of a lifestyle, business or country exceeds the area available to the population (also known as the biocapacity—the amount of resources that the planet can provide sustainably), it means that it is not sustainable in the long-term
In the UK, for example, the ecological footprint is estimated to be about 4.2 global hectares (gha) per person per year, whilst the biocapacity is only around 1.7 gha per person per year, indicating that the UK population is living unsustainably
To reduce an EF, it is important to adopt more sustainable practices, such as reducing meat consumption, using renewable energy sources and using public transport or walking instead of driving
EFs are a useful tool for promoting sustainable development and for raising awareness about the impact of human activities on the environment
Other sustainability indicators
Carbon footprints
The carbon footprint measures the amount of greenhouse gases (GHGs) produced by a person, activity, business or country
Carbon footprints are usually measured in carbon dioxide equivalents (in tonnes) per year
Carbon footprints can help us understand how much our actions contribute to global climate change
For example, the carbon footprint of a UK citizen is approximately 5.5 tonnes of CO2 per year
Water footprints
Water footprints measure the amount of water used directly or indirectly to produce certain goods and services
For example, this could include water used for crop irrigation or water used for manufacturing processes
Understanding water footprints helps us manage water resources more sustainably
Water footprints are usually measured in cubic metres per year
Exam Tip
Ensure you understand the definitions of key terms like ecological footprint and biocapacity.
While you need to be familiar with ecological, carbon and water footprints (particularly in terms of interpreting data and comparing results), you do not need to know details of how these footprints are calculated.
Did this page help you?