Carbon footprint
What is a carbon footprint, and why is reducing it so important to combating climate change?
Energy efficiency Decarbonisation Energy transition Climate action
Whether we are driving a car, taking an aeroplane journey or even consuming everyday foodstuffs such as beef, we are leaving an invisible carbon footprint. So many of our day-to-day activities leave a trail of greenhouse gas emissions behind, gases that are released into the atmosphere and trap heat, thus contributing to climate change. Being aware of an activity’s carbon footprint, which is measured in tons of CO2, is important when it comes to taking measures and launching initiatives to reduce these emissions to the lowest possible level. The responsibility for doing so, in order to avoid catastrophic climate change, falls to individuals, companies and governments.
The trace of the greenhouse gases produced by human activities is known as the carbon footprint.
Every time you travel by car, charge your mobile phone, switch on the TV or run the washing machine, and many other routine activities, you leave a trail of gases in your wake that build up in the atmosphere and contribute to global warming. These emissions speed up climate change, warns the United Nations (UN) in its Sustainable Development Goals (SDG), and if we do not neutralise them in time by decarbonising the economy and through other measures such as environmental taxes, a far more inhospitable world is just around the corner.
What is a carbon footprint?
The trace of the greenhouse gases produced by human activities is known as the carbon footprint. This environmental indicator measures both direct and indirect emissions of compounds such as methane (CH4), nitrogen oxide (N2O), hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), sulphur hexafluoride (SF6) and, above all, the most abundant and most important contributor to global warming since 1990: carbon dioxide (CO2).
How to calculate your carbon footprint
There are a number of different methods to help you calculate your carbon footprint, such as this online calculator provided by the United Nations Carbon Offset Platform. The tool collects detailed information about your household, such as the number of people in it, your electricity consumption, your transport habits, including how many flights you take every year, and lifestyle choices such as how much meat you eat and whether or not you buy from environmentally responsible companies.
It will then calculate your total annual emissions as a household in tonnes of CO2, and offer you the average for your country as a comparison, as well as the world average. In Spain, for example, the average total emissions for a household is 20.14 tonnes of CO2, while the global average is 18.68 tonnes. This approach makes it easier to understand the environmental impact of your lifestyle and allows you to identify areas to reduce your carbon footprint.
Knowing your carbon footprint, whether at a personal or organisational level, is useful for a number of reasons:
- Identification and reduction of emissions: It allows you to identify sources of greenhouse gases (GHGs) and establish measures to reduce them.
- Corporate transparency: Companies can use this information to publish statistics on their environmental performance, strengthening their commitment to sustainability.
- Awareness raising: Serves as an educational tool to help raise awareness among individuals and organisations about the environmental costs of their activities.
- Environmental and energy management: It facilitates the design and implementation of more efficient strategies to manage resources and reduce negative impacts on the environment.
In short, carbon footprinting is a key tool for moving towards more sustainable development.
What factors have the biggest effect on your personal carbon footprint?
Family size
According to Conservation International, no other single factor has such a big effect on your carbon footprint as the number of children you have. Each child in your family adds an average of 58 tonnes of CO2-equivalent every year, according to the organisation. This impact exceeds that of other individual habits or decisions, underlining the importance of considering family size in the context of environmental sustainability.
Transportation
Cars and aeroplanes are two of the biggest contributors to personal carbon footprints. Car owners who regularly use their vehicle generate, on average, 2.4 tonnes of CO2 per year. Meanwhile, a single transatlantic flight has a significant impact, adding around 1.6 tonnes of CO2.
Heating and air conditioning
If you need to regularly heat and cool your home, depending on the season, you are likely adding 1.5 tonnes of CO2-equivalent to your annual footprint, especially if your energy is coming from so-called “dirty” sources such as coal and gas instead of renewables. Coal, for example, produces 870 grams of CO2 per kilowatt of power, according to Conservation International, compared to just 48 grams of CO2 for solar and 11 grams for wind.
Food
Meat adds around 0.8 tonnes of CO2-equivalent to your annual carbon footprint, partly due to the emissions of gases such as methane from the animals’ digestive tracts, but mostly because of the energy required to grow, harvest and process crops that are used as feeds for the livestock.
The carbon footprint of companies
Like human beings, companies also produce greenhouse gases during manufacturing, transport and energy consumption. The corporate footprint measures all GHG emissions from companies and their scope, whether they are direct and controllable or not.
In this regard, companies usually have the option to reduce or offset their carbon footprints. How? By improving their energy efficiency, consuming energy that is 100% renewable, running campaigns to raise awareness, investing in environmental projects, paying green taxes and buying tonnes of CO2 on the international emissions market, among other options.
Carbon footprints in figures
16 tonnes
The average carbon footprint for a person in the United States
4 tonnes
The average global carbon footprint per person
<2 tonnes
The target footprint to avoid a 2ºC rise in global temperatures
16 tonnes
The average carbon footprint for a person in the United States
4 tonnes
The average global carbon footprint per person
<2 tonnes
The target footprint to avoid a 2ºC rise in global temperatures
Net Zero
Net zero 2030
What is decarbonization?
Regulatory principles and actions relating to energy decarbonisation
What is energy efficiency?
The benefits of energy efficiency
Carbon markets
How are emission allowances and carbon credits markets regulated?
Carbon neutrality
Carbon neutrality, what is it and why is it vital for the future of the planet?
Science Based Targets
The Science Based Targets initiative
The role of offsetting schemes in reducing a carbon footprint
If an individual cannot – or does not want to – avoid an activity that leaves behind a carbon footprint, they now have a wealth of options and schemes when it comes to offsetting those greenhouse gas emissions. Offsetting is a climate action that is available to both individuals and companies, and allows them to compensate these emissions by supporting worthwhile projects that reduce emissions elsewhere.
To be able to quantify this offsetting, the United Nations (UN) has created a measurement called Certified Emission Reductions (CERs). CERs are generated by what are classed Clean Development Mechanism (CDM) projects, which are located in developing countries, and earn one CER for every metric tonne of greenhouse gas emissions that they either reduce or avoid. These in turn are measured in CO2 equivalent, which is represented by the symbol CO2-eq.
CERs can then be purchased by individuals or by organisations as a way of offsetting their own emissions. The UN describes the scheme as like “crowdfunding for climate action”, as purchasing CERs is a direct financial contribution to projects that not only reduce emissions, but also benefit communities.
How do carbon-offsetting projects reduce emissions?
According to the UN, CDM projects have been responsible for avoiding more than 1.8 billion tonnes of greenhouse gas emissions so far, which is the equivalent of taking more than 300 million cars off the road or installing 400,000 wind turbines. Here is how CDM projects can reduce emissions.
- Transition to clean energies: Replacing the use of polluting fossil fuels with clean, renewable energy such as wind, hydro, solar and biomass.
- Energy efficiency: Reducing energy consumption and fossil fuels through energy-efficiency measures, such as clean cooking stoves and energy-efficient light bulbs.
- Carbon capture: Through natural sinks such as trees and other plants, reforestation and forest-regeneration projects sequester carbon that has already been released into the atmosphere, helping to restore the environmental balance.
How do offsetting projects reduce emissions, and what are their benefits?
If the objectives of the Paris Agreement are to be met, and the global temperature rise is limited to less than 2ºC before the end of the century, offsetting projects will play a key role. Their aim is to bridge the gap between the present day and a future moment when societies have phased out technologies that pump greenhouse gases into the atmosphere. Among the benefits of these offsetting projects, according to the UN, are:
Supporting sustainable development: They contribute to the economic and social development of developing countries, creating opportunities that benefit local communities.
Multiple benefits for communities: They address climate change while improving people's quality of life, driving improvements in areas such as health, education and wealth creation.
Promoting responsible industrial practices: They help promote a shift towards more sustainable and responsible industrial practices, encouraging companies to adopt clean technologies and reduce their environmental impact.
Encouraging behavioural change: Offset projects encourage changes in the behaviour of both companies and individuals, including consumers. These changes can generate a multiplier effect, influencing industries, institutions and networks, accelerating the transition to a more sustainable future.