Sustainability (Junior Cert Science): Revision Notes
📚Revision Notes
Sustainability
What is sustainability?
The word sustainability comes from the Latin word "sustinere," which means to maintain or to support. Understanding sustainability is crucial for protecting our planet and ensuring a good quality of life for everyone, now and in the future.
Sustainability means using a resource in such a way that it does not run out. It is about meeting our current needs without compromising the ability of future generations to meet their own needs.
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Key aspects of sustainability include:
- Ensuring the Earth will continue to provide fresh air, food and water for people to enjoy a good quality of life for ourselves and for all future generations
- Avoiding damaging the environment while also maintaining our natural resources at a certain level so they do not become completely used up
- Using what we need to live at the present time without damaging the ability of people in the future to meet their own needs
- Activities that are not harmful to the environment and that support long-term balance in the world's ecology
Sustainable development is development that meets the needs of present and future generations without compromising the ability of future generations to meet their own needs. This is a long-term process that affects us all and involves ongoing efforts to improve the quality of our lives and the lives of future generations.
The three pillars of sustainability
Sustainability is often explained using three interconnected pillars that work together to achieve true sustainable development.
The three pillars are:
Social pillar
This pillar focuses on people and communities. It involves ensuring fair treatment, good working conditions, access to education and healthcare, and maintaining cultural diversity. Social sustainability means creating communities where everyone can thrive.
Environmental pillar
This pillar concerns protecting the natural world. It includes preserving ecosystems, reducing pollution, conserving resources, and maintaining biodiversity. Environmental sustainability means keeping our planet healthy and protecting natural resources for the future.
Economic pillar
This pillar relates to financial systems and growth. It involves creating economic opportunities whilst using resources wisely. Economic sustainability means ensuring prosperity without damaging the environment or society.
Important
These three pillars are not separate – they reinforce each other. For example, better environmental practices (like using local food) can support better-quality food and water (environmental pillar). This leads to a healthier population and, consequently, less expensive health costs (economic pillar).
To solve the overall challenges of sustainability, we must address social sustainability, environmental sustainability and economic sustainability together.
Sustainability and population growth
Serious concerns have arisen in recent years about the rapid growth in the world's population, which presents a significant challenge to sustainability.
The world's population is growing rapidly. Historical data shows that population remained relatively stable for centuries but has increased dramatically in recent times. It is predicted that the population will reach as high as billion by .
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The impacts of population growth on sustainability include:
- Increased demand for resources: More people need more clean air, clean water and food
- Pressure on land: An increased population puts greater pressure on land and raw materials. More land is needed for building new houses and for increasing the sizes of towns and cities
- Higher consumption: An increase in population means an increase in the consumption of natural resources
- Regional challenges: Sustainability is particularly challenged by a combination of high population increase in the developing world and high consumption in the developed world
Most of the population increase is taking place in developing countries, whilst developed countries have higher consumption rates per person.
Life expectancy and population
The increased life expectancy contributes to an increase in population. In the developed world, you can expect to live longer than your ancestors. This increased life expectancy is caused by factors such as improvements in medical care, the fall in infant mortality, the development of new medicines, the improvement in water quality, the availability of good food and the overall improvement in living conditions.
Example
Life Expectancy Changes in Ireland
The table below shows how life expectancy has increased dramatically in Ireland over approximately one century:
| Life expectancy if born in Ireland in 1901 | Life expectancy if born in Ireland in 2014 |
|---|---|
| Males: 49 years | Males: 78 years |
| Females: 50 years | Females: 83 years |
This represents an increase of approximately 29-33 years in life expectancy over just one century!
Increased life expectancy in developed countries is contributing to an increase in population.
Sustainability and fossil fuels
To understand the challenges facing sustainability, we need to examine the role of fossil fuels. Understanding what fuels are and how we use them is essential to this topic, often studied through a case study of fossil fuels and their environmental impact.
What are fuels?
Burning fuel was one of the first chemical reactions used by humans. Any substance that burns in oxygen (or air) to produce heat is called a fuel.
We burn fuels to perform many tasks, such as:
- Keeping us warm
- Cooking food
- Generating electricity
- Running vehicles
- Powering diesel engines
The most commonly used fuels in the world are coal, oil and natural gas.
Fossil fuels
Coal, oil and natural gas are commonly called fossil fuels. These are fuels that contain the remains of plants and animals that lived millions of years ago.
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Formation of fossil fuels
The formation of fossil fuels occurred over millions of years through a complex process:
- Plants absorbed the sun's energy through photosynthesis
- Animals ate the plants (and some animals ate other animals)
- When these plants and animals died, their remains were buried deeper and deeper over millions of years
- The pressure exerted by the earth and the sea on these remains turned them into our supply of coal, oil and natural gas
There are many examples of fossil fuels:
- Solid fossil fuels: coal and turf
- Liquid fossil fuels: petrol, diesel and paraffin oil (kerosene)
- Gaseous fossil fuels: natural gas (mainly methane, with chemical formula )
Hydrocarbons
Although the three types of fossil fuel look completely different, they all consist of similar types of compounds. These compounds are called hydrocarbons.
Hydrocarbons are compounds consisting of hydrogen and carbon only.
Combustion of fossil fuels
When hydrocarbons are burned, carbon dioxide and water are formed. Since fossil fuels contain hydrocarbons, when these fuels are burned, carbon dioxide and water are always formed.
The general equation for combustion of fossil fuels is:
Example
Combustion of Methane (Natural Gas)
When methane (natural gas) is burned:
In chemical formula form:
This shows that one molecule of methane reacts with two molecules of oxygen to produce one molecule of carbon dioxide and two molecules of water.
As more fossil fuels are burned, increased levels of carbon dioxide gas are building up in the atmosphere.
Carbon dioxide is one of the main greenhouse gases. Without these greenhouse gases, the Earth would be too cold for life on Earth to exist. However, scientists are concerned that increasing concentrations of carbon dioxide are causing the Earth to get warmer.
The greenhouse effect
This natural trapping of the sun's energy by the atmosphere is called the greenhouse effect. The atmosphere acts like the glass in a greenhouse, allowing sunlight through but trapping heat.
Important
The enhanced greenhouse effect occurs when increasing concentrations of greenhouse gases, particularly carbon dioxide, cause additional warming. This is concerning scientists worldwide.
The extra warming that results from the enhanced greenhouse effect is called global warming.
In addition to concerns about global warming, there is also concern that the supply of fossil fuels on Earth is running out.
Non-renewable resources
This type of fuel is said to be a non-renewable fuel. Once the fossil fuels are used up, there will be no more left. The formation process took millions of years, so they cannot be replaced in human timescales.
Therefore, in order to have sustainable development we must reduce our dependence on fossil fuels. Because of this, scientists are now developing biofuels as alternatives.
Biofuels
Biofuels are fuels made from plants, for example rapeseed oil and sunflower oil.
Biofuels work well alone or mixed with other fuels, such as petrol and diesel. They are often described as green fuels and are better for the environment. Although these fuels produce carbon dioxide when they burn, they absorb carbon dioxide when they are growing. Therefore, these fuels are said to be greenhouse neutral.
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Advantages of Biofuels
One of the advantages of biofuels is that more plants can be grown to produce more fuel. Therefore, biofuel is called a renewable fuel.
The development of biofuels is a good example of sustainability in action. A renewable substitute is being developed to take the place of the non-renewable fossil fuels. In addition, the fact that biofuels are greenhouse neutral means that they have a big advantage over fossil fuels.
Extraction and use of materials – implications for sustainability
Many raw materials are obtained from the Earth. These raw materials are used to make many useful products.
Examples of these raw materials and their uses are summarised below:
Coal
Coal is dug from mineshafts deep underground or near the surface. Coal is used as a fuel.
Crude oil and natural gas
These are extracted from the ground. Crude oil is used in oils, petrol, diesel, plastics and bitumen for roads. Natural gas is used mainly as a fuel.
Metal ores
Many metals are extracted from ores in the ground. There is a huge demand for copper in the electronics industry.
Timber
Timber is used for building houses, making furniture and as a fuel.
The extraction of the materials shown above and their uses have implications for sustainability.
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Sustainability Implications
Fossil fuels: As already discussed, burning fossil fuels has implications for sustainability. Therefore, biofuels are being developed as renewable alternatives.
Timber: Efforts are being made to make sure that forests are sustainable. In other words, no more timber is cut than can be regrown.
Mining: Particular problems are associated with mining, as the metal ores are non-renewable. Because of this, recycling metals, such as scrap iron, aluminium cans and copper metal, plays an important role in sustainability.
Disposal and recycling of materials – implications for sustainability
As the population of the world continues to rise, the demand for raw materials also continues to increase. This results in increased amounts of waste being produced, which leads to increased pollution.
Pollution is the addition of harmful substances to the environment in quantities greater than can be dealt with efficiently by the environment itself.
Important
Common Pollutants
Some examples of pollutants include:
- Fertilisers: Help to produce more food, but excessive amounts can cause algal blooms in rivers
- Litter: Small pieces of plastic (microplastics) are becoming major sources of pollution. They build up in the bodies and tissues of many organisms
- Sewage: Raw sewage contains human waste, industrial waste and slicks. Microorganisms present can cause disease
- Toxic substances: Fertilisers contain metals such as lead, mercury and cadmium. These can cause pollution in rivers, lakes and seas
- Air pollution: Burning fossil fuels produces and . An increase in is thought by scientists to be contributing to global warming. is harmful to the environment
Throughout the world, environmental protection agencies are being set up with laws being put in place to control and prevent pollution. The proper disposal and recycling of materials poses considerable challenges to sustainability.
Recycling plastics
Recycling plastics is important for a number of reasons:
- It saves an important natural resource: oil
- It helps to keep the cost of plastics low when oil becomes too costly or is in short supply of raw material
- It keeps the cost of waste disposal down. Plastic materials make up about per cent by volume of domestic refuse
- It helps to reduce litter. Since most plastics are non-biodegradable, discarded plastics can become one of the worst forms of litter
Sustainable development helps to reduce the cost of non-renewable resources such as oil and metals because the prices of these items rise as they become less plentiful. In addition, sustainable development reduces the huge clean-up cost of environmental pollution.
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General Principles for Sustainability Success
For sustainability to be successful, we need to make sure that:
- For renewable resources, the rate of harvest should not exceed the rate at which these resources can be regenerated
- For non-renewable resources, the depletion of the non-renewable resources should require the development of renewable substitutes for these resources
- For waste disposal, the rate of waste generation should not exceed the capacity of the environment to absorb this waste
How can we as individuals contribute to sustainability?
When we travel by car or plane, both the car and the plane release carbon dioxide into the atmosphere. Similarly, if we buy food that has been produced in other countries, a certain quantity of fuel has to be burned to bring it to our local shop.
The term carbon footprint is often used as a measure of our sustainable lifestyle.
Carbon footprint is a measure of the amount of carbon dioxide released into the atmosphere as a result of the activities of a particular individual, organisation or community through burning fossil fuels.
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Practical Actions to Reduce Your Carbon Footprint
Some examples of ways that we can reduce our carbon footprint and contribute to sustainability include:
- Reduce packaging: Do not buy items with unnecessary packaging
- Use energy-efficient lighting: Use low-energy light bulbs and turn them off when not needed
- Shop locally: Buy products that are made locally and reuse shopping bags
- Active transport: When possible, walk or cycle to school or work instead of driving
- Conserve water: Take showers rather than baths to conserve water
- Reduce air travel: Take holidays at home rather than flying abroad
- Recycle: Recycle as much as possible using the appropriate coloured bins
Sustainable development is a long-term process and affects us all. It involves ongoing efforts to improve the quality of our lives and the lives of future generations. By making conscious choices in our daily lives, each of us can contribute to a more sustainable future.
Summary
Key Points to Remember:
- Sustainability means using resources so that they do not run out, ensuring the Earth can continue to support current and future generations
- The three pillars of sustainability are the social pillar, the environmental pillar and the economic pillar – all three must work together
- Fossil fuels (coal, oil and natural gas) are non-renewable resources formed from ancient plants and animals over millions of years
- Burning fossil fuels releases carbon dioxide and water, contributing to the greenhouse effect and global warming
- Biofuels are renewable alternatives to fossil fuels, made from plants, and are considered greenhouse neutral
- Recycling and proper waste disposal are essential for sustainability, helping to conserve resources and reduce pollution
- Individual actions such as reducing energy use, recycling, using local products and choosing sustainable transport can significantly reduce our carbon footprint