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Introduction to Sustainable Development

Updated 2019-08-13

Sustainability as an idea has existed for a long time, but there is a growing focus on sustainable development since the 1950s due to rapid increase of population, wealth, and health for all countries.


The main drivers for sustainable development are due to rapidly economic growth in all countries. The main drivers are increasing population and increasing consumption per capita. Both of which will place an impact on society.

Video on rapid growth of countries.

Driver: Increasing Population

Because of better health, there exists a world population growth. It is estimated that the world population will reach 10 billion by the year 2055.

Driver: Increasing Per Capita Consumption

Because of better wealth, people are consuming more resources. Canadians have one of the highest per-capita consumption rates. The per capita material footprint is the the sum of extracted material (typically non renewable) required for each person.


The increase of both population and consumption per capita will lead to economic and ecological impacts. These impact could be positive (good) or negative (bad). The social or environmental impact can be roughly described by:


Some of the impacts we observe today are:


The working definition of sustainable development, according to United Nations1 is:

Developments involving systems thinking that meets the needs of the present while providing society, environment, and economy wellness without compromising the needs of future generations to meet their own needs.

The UN created 17 sustainable development goals (SDGs) where each goal has well defined targets and indicators. They can be found on UN sustainable development website2.

Carrying capacity is the number of people who can be supported over a long period of time. Living within the carrying capacity depends on:

Biocapacity is the productivity of land areas such as forests, croplands, fisheries, and land for absorbing human waste.

Ecological footprint (EF) measures the current human demand on earth’s ecosystems and natural resources. EF provides an estimate of the area of biologically productive land and sea to sustainably support human activities. The unit is [area/year]. The method of calculating EF is outlined here3.

Ecological deficit is when the total ecological footprint is greater than the total biocapacity of the area available to that population.

Natural capital is the natural resources on Earth’s biosphere that provide ecosystem goods and services imperative for survival and well-being 4. Like financial capital, the idea is that we use the what we have in a way to ensure abundance of capital is maintained or increased over time.

Climate Change

To reduce the worst-case impacts of the climate change, we need to reduce our GHG emissions significantly to limit. There is a need to limit the average global temperature increase to 1.5 degrees Celsius before 2030.

UN Intergovernmental Panel on Climate Change (IPCC) works together to develop a strategy. They publish a report with models and predictions every few years.

The Paris Agreement

The Paris Agreement was adopted by 195 countries in December 2015 at International Agreement on Climate Change (COP 21). The key agreements are:

Green House Gases

Green house gases (GHG) should be considered in any engineering project. GHGs are any gas in the atmosphere which traps heat in earth’s atmosphere.

To quantify the effects of GHGs, we use Global Warming Potential (GWP) index referenced to with $\ce{CO2}$.

Carbon dioxide $\ce{CO2}$ (reference) 1
Methane $\ce{CH4}$ 21
Nitrous Oxide $\ce{N2O}$ 310
Hydrofluorocarbons $\ce{HFC}$ 124-14,800
Perfluorocarbons $\ce{PFC}$ 7,390-12,200
Sulfur hexafluoride $\ce{SF6}$ 22,800
Nitrogen trifluoride $\ce{NF3}$ 17,200

Sometimes we express how impactful a GHG is by quantifying them in terms of \(\ce{CO2}\) equivalent by multiplying the mass of GHG by their GWP.

Carbon footprint describes the contribution of global warming of human activity. It is the land and sea required to sequester the equivalent CO2 by human activity in Global hectares. The carbon footprint is a slice of the total ecological footprint.


Biodiversity Loss

Biodiversity loss is considered as significant as climate change. They are important because humans cannot survive without healthy and resilient ecosystems.

Biological diversity (biodiversity) refers to the variety of specifies and ecosystems 6 as three components:

  1. Ecosystem diversity
  2. Species diversity
  3. Genetic diversity

Biodiversity loss occurs even with absence of humans but happen at a low rate and do not result in gene pool or ecosystem loss. About 60% of the animal population have been lost since 1970 due to human activities.



Climate change is considered the main cause of biodiversity. Other significant human activities also cause significant biodiversity loss:


Biodiversity losses could lead to, but not limited to, some of the following 7:

Ultimately, biodiversity loss leads to lower quality of ecosystems humans need to function.

Ecosystems Services

A healthy ecosystem supports or provides benefits humans physically, mentally, and socioeconomically. The support is called ecosystems services. They are services of:


  1. United Nation - Sustainable Development Agenda: 

  2. United Nation - Sustainable Development Goals: 

  3. Global Footprint Network - Data and Methodology: 

  4. International Institute for Sustainable Development - Natural Capitalism: 

  5. Global Footprint Network - Climate Change: 

  6. BioDivCanada:

  7. - Biodiversity Loss and Its Impact on Humanity: