A carbon footprint is the name given to the total amount of greenhouse gas emissions generated by something or someone over a specified period.
It’s a simple way to express the impact of our activities on the environment.
Greenhouse gas emissions, such as carbon dioxide, methane, nitrous oxide and fluorinated gases, cause global warming and climate change. The larger a footprint, the more greenhouse gases are being released into the atmosphere.
Let’s look at some examples.
An individual product, such as a television, has a carbon footprint. That’s because greenhouse gases come from its production, its use and its disposal.
A company has a footprint through the carbon dioxide and other greenhouse gases released into the atmosphere from e.g. its manufacturing processes, buildings, transportation of products and employees and waste disposal processes.
You have a personal carbon footprint through the greenhouse gas (GHG) emissions linked to the things you buy, services you use, and other choices that you made in your day-to-day life. You might think that as long as you don’t own a car, you aren’t emitting carbon dioxide. But emissions come from everything we buy, from what we eat, from how we heat and furnish our homes and in particular from how we, and the things we buy, travel.
A country has a carbon footprint from summing all the activities of its entire population. So our individual actions are part of the total GHG emissions on earth, and it all adds up!
The average individual’s carbon footprint, globally, was about 5 tons in 2020. But there was a large variation by country. For example, in Australia, the average person had per capita carbon dioxide emissions of about 17 tons, closely followed by a per capita carbon footprint in the US and Canada at about 16 tons. At the other end of the scale, the average person in India had a footprint of about 2 tons.
But in reality, everyone’s footprint is different, depending on factors such as their location, their income, their daily habits and their personal choices.
By reducing your personal carbon footprint, you reduce the amount of greenhouse gas emissions that are released into the atmosphere, helping to slow down and eventually even reverse climate change.
There is a lot of work still to do.
To meet the 2015 Paris Agreement, it’s estimated that the average global footprint needs to fall to under 2 tons by 2050. But, the global footprint (measured by total annual CO2 emissions) to date just keeps on increasing.
Read on to learn more about
- What affects your carbon footprint?
- What is a carbon footprint of something we buy?
- How is a carbon footprint measured?
- What is the difference between an ecological footprint and a carbon footprint?
- Calculate your carbon footprint
- The best carbon footprint calculators
- How to reduce your carbon footprint
- How to offset your carbon use
What affects your carbon footprint?
In developed countries, most people’s carbon footprint comes from how they travel, their homes, what they eat and what else they buy.
For example, this chart shows these factors each contribute about one quarter of the footprint of the average person living in the UK.
Contribution to the average person’s carbon footprint in the UK
Every time you do something that requires burning fossil fuels, you are increasing your carbon footprint. For example, this could include taking a flight, heating your home with coal, natural oil or gas, buying a physical product, eating imported food or using something that uses non-green electricity.
One part of your footprint is generated by you directly. This is called the primary footprint. It includes emissions you cause as a direct consequence of your actions. For example, when you drive a petrol or diesel car somewhere.
The secondary footprint includes also the greenhouse gas emissions linked with indirect actions e.g from how a manufacturer has produced a good or service you buy. It includes the sum of the emissions from the production, use and end life of all products and services you consume.
For example, a pen made from recycled materials produced in your local town will have a much smaller footprint than a pen made of new plastic, with a steel cap, flown to you from the other side of the world. The secondary footprint takes this additional use of resources into account.
Decisions we take on which products to buy and from which companies are important in reducing our individual carbon footprint.
What is a carbon footprint of something we buy?
Any physical product that we buy has a carbon footprint.
We can look at all the carbon that’s associated with it. From the point it’s made, during its use, to its disposal at the end of its life.
We can say that the carbon footprint of a product is made up of:
The Manufacture
The carbon footprint linked to a product’s manufacture includes the gathering of the raw materials used to make it, such as wood from a forest, or ore from the ground to make metal.
It also includes the manufacture of any components a product needs.
Added to this is the manufacture of the product itself.
Plus any transportation involved in any of the above steps.
In other words, there are emissions associated with the extraction or creation of the raw materials used to make any components as well as the final product itself.
The Use
The footprint linked to a product’s use typically includes the energy needed to run it.
For example the electricity used in charging your phone or in running your washing machine.
Both the energy efficiency and the energy source is important.
This also includes the ghg emissions linked to any repairs and maintenance.
End of life
The footprint linked to a product’s end of life includes the carbon emissions from its recycling or landfill disposal.
Which of the three parts of a product’s footprint is largest varies, depending on the individual product.
Let’s look at a few examples:
A boiler. This is a product used in many homes to keep them warm and to heat up water. The largest part of its carbon footprint is from use. Here, carbon dioxide emissions are typically generated from the burning of natural gas or oil or the use of non-green electricity.
To reduce its carbon footprint, it’s important that the energy used is green, and that the boiler has a high efficiency rating – namely it uses that energy as efficiently as possible.
A Petrol car. Also in this example, the largest carbon footprint comes from its use through the petrol that it burns. But the manufacture of the car is also an important component of its footprint because of the large amount of metal it needs to make a car.
To reduce the carbon footprint the car could be driven economically, to use less petrol, while carrying as many passengers as possible. on each journey.
An Electric car. Similar to the petrol car, the largest carbon footprint comes from its use and whether the electricity used to power is green energy from a renewable source or not.
If the electricity used to run the car comes from a green source, then the footprint of an electric car is far far lower than from a traditional diesel or petrol car.
In that case, the largest part of its footprint comes from the manufacture and disposal of its battery.
IT products e.g. a laptop computer. For computers, the manufacture creates the largest part of its footprint. To reduce this, its crucial to use every computer for as many years as possible.
Furniture e.g an armchair. Here too, the manufacture is the point at which most of the carbon footprint is produced and the size of the carbon expenditure will depend on the materials used and the energy spent in the production process. Once made, an armchair doesn’t need any energy, until the point of its recycling or disposal.
A House. The carbon footprint from the construction of a house can be very significant, depending on the use of materials. Particularly steel and cement cause high carbon dioxide emissions. The running costs of a house are also a significant, with components such as gas boilers and air conditioning significantly increasing the household carbon footprint. Alternatively, the use of green energy and passive construction have the potential to significantly decrease the footprint linked to house construction.
How is a carbon footprint measured?
A carbon footprint measures the total volume of greenhouse gas emissions. These are the gases that, when released into the atmosphere, cause climate change.
Although carbon footprints usually measure the volume of all the main greenhouse gases (CO2, methane, nitrous oxide and fluorinated gases), it’s usually expressed in CO2 equivalence.
This makes it easier to directly compare the absolute size of various carbon footprints.
Carbon footprints can differ from a country’s reported per capita emissions.
This is because reported emissions focus solely on the emissions produced in that specific country. In other words, this measure excludes the emissions linked to the production and transport of imported goods produced elsewhere in the world and bought into the country.
As a result, carbon footprints can increase even when per capita emissions decrease.
This would be the case, for example, if a country imports more from abroad. It produces less at home, so per capita emissions decrease. But it is now buying more goods from abroad, so its total footprint is increasing.
What is the difference between an ecological footprint and a carbon footprint?
An ecological footprint is how much land and water area we need to produce the resources we use and to absorb our waste.
A carbon footprint is just part of that. It’s the amount of CO2 equivalent that is released into the atmosphere because of our activities.
Worldwide, the carbon footprint is about 60% of the ecological footprint.
Calculate your carbon footprint.
For a rough idea of your carbon footprint, you can take the average value of emissions per person for the country you live in.
But we don’t all produce the average carbon footprint.
For some of us, our footprint will be larger, depending on the types of things we buy.
For a more personalized measurement, you can use a carbon calculator.
A calculator also helps you to understand where your footprint comes from.
The best carbon footprint calculators
There are many calculators available online, using a number of different methodologies.
Many incorporate information on the average footprint in the country where you live, so depending on where that is, you might want to try one of the following:
- If you live in the US, try: https://coolclimate.org/calculator
- If you live in the UK, try: https://footprint.wwf.org.uk
- Live somewhere else? try: www.carbonfootprint.com/calculator.aspx
Most calculators will use information on factors such as how much energy you use to heat your home, what you eat, how much driving and flying you do, how much money you spend on food, clothes, technology etc. The calculator calculates how many metric tons of CO2 equivalent that is.
Adding it all together, you get your carbon footprint.
You can also find a calculator for car efficiency here: https://fueleconomy.gov/
How to reduce your carbon footprint
Once you know what your carbon footprint is, what can you do about it?
Well, you can both reduce the carbon emissions associated with your life-style and offset them.
To help reduce your carbon footprint, inform yourself about the energy that goes into producing the things you own, running them and then disposing of them.
For every new purchase inform yourself about the materials being taken out of the ground to make those things, the manufacturing process, their use and then their disposal.
We can reduce the emissions we produce by:
- Buying less
- Choosing lower carbon products
- Buying fewer better quality items and using them for longer
- Maintaining and repairing things
- Sharing or borrowing rather than owning
- Repurposing old things into new
- Buying second hand rather than new items
- Informing ourselves about the carbon footprints of the companies we buy from and then buying from those that take care of the environment and have a net zero policy
- Buying things locally whenever possible
When you change your buying behaviour to buy only low carbon products, you can reduce your own personal carbon footprint.
You can also send a clear signal to companies that you care about the carbon pollution they create and their carbon footprint and that they need to reduce it.
How to offset your carbon use.
Offsetting means paying money to a carbon project which has been designed to reduce emissions somewhere in the world.
The amount you pay depends on the size of your carbon footprint and the amount of emissions you want to offset.
Examples of ways to offset your emissions include planting trees, building a wind farm or building a solar power farm.
Sometimes offsetting can sound like a great deal. For example, you might be able to plant enough trees to offset a large proportion of your emissions at a relatively low price.
But you need to understand that offsetting does not keep carbon in the ground.
It risks encouraging people not to change their behaviour and to keep burning fossil fuels.
And it could be compared with actions like killing polar bears, while at the same time donating money to the WWF to protect them.
Carbon offsetting IS a great way to fund tree planting.
And carbon offsetting can help to fund renewable energy projects. This is essential to help and speed up the transition away from the burning of fossil fuels.
But in addition, we have to change our lifestyles to reduce our personal carbon footprints, keep fossil fuels in the ground and plant trees.
There are 3 priorities in this respect:
- Swap to using renewable energy for your home and business.
- Stop flying and driving a petrol or diesel car.
- Question the value that any new purchase makes to your life. Make it a high value one and make it low carbon.
Want to know more about carbon capture? Read about the climate change and the ocean.