CARBON FOOTPRINT: WHAT IT IS FOR, HOW IT IS CALCULATED AND EXAMPLES - ENVIRONMENT

The carbon footprint is a measure of the amount of greenhouse gases emitted by humans from the activities of products and services. Monitoring this variable has become important due to its effect on global warming and climate change.

In different international agreements, the industrialized countries have assumed the commitment to achieve the reduction of emissions in order to avoid a catastrophic increase in the temperature of the planet in the coming years.

Carbon footprint. Source: www.flickr.com

There are different methods for calculating the carbon footprint. The most common methods today take into account the emissions that occur throughout the life cycle of the product, from obtaining the raw material to its final disposal.

The reduction of the global carbon footprint requires an integrated approach that combines the reduction of energy consumption, the reduction of the intensity of greenhouse gases in the end-use sectors (transport, industry, residential, among others), the decarbonization of the supply of energy, reduction of net emissions and enhancement of carbon sinks.

What is the carbon footprint for?

The carbon footprint is used to measure greenhouse gas emissions. It is an indicator that can be used as a measure of the environmental impact produced to obtain a specific product or service.

Greenhouse gases

Emissions of greenhouse gases. Source: www.pixabay.com

Greenhouse gases are those gaseous components that absorb and re-emit infrared radiation.

Solar radiation is made up of high frequency waves, which easily pass through the atmosphere. The surface of the Earth absorbs solar energy and re-emits it in the form of lower frequency waves, which are absorbed and re-emitted by greenhouse gases. This retention of waves in the atmosphere causes the Earth's temperature to increase slowly.

The increase in greenhouse gas concentrations is due to the massive emissions produced by industrial activities for the production of goods and services, and by the high consumption patterns associated with modern societies.

The main greenhouse gases are carbon dioxide, methane, nitrogen oxides, and chlorofluorocarbons.

How is it calculated?

The carbon footprint is an indicator of greenhouse gas emissions that can be evaluated through different methods, with different interpretations of this indicator. The four main methods are described below.

Greenhouse gas protocol

This protocol was implemented in 2001 by the World Business Council for Sustainable Development and the World Resources Institute. It is a corporate-focused approach used on a business scale that has achieved a high level of recognition worldwide.

The indicator covers all the activities carried out by the company. Includes direct emissions from the use of fuels under the control of the company and indirect emissions from electricity consumption, as well as indirect emissions outside the control of the company.

Within the framework of the greenhouse gas protocol, free computer programs have been developed for calculating the carbon footprint, which are very successful and in high demand.

Carbon balance

The carbon balance method was developed in 2002 by the French Environment and Energy Agency. It was developed with a corporate focus but can be applied at a company, territory or product scale. This method of measuring emissions is the benchmark in France.

The method considers both direct and indirect emissions, mainly linked to the productive activities of companies, such as energy consumption, transport requirements and distances traveled, the amount of raw material required, among others.

Like the greenhouse gas protocol, this method considers both direct and indirect emissions under the control of the company (from fuel use or energy consumption), as well as indirect emissions outside the control of the company.

Publicly available specifications

The publicly available specification method, also called PAS 2050 for its acronym in English (Publicly Available Specification), emerged in 2007 as a tool of the English government for the measurement of greenhouse gas emissions.

Its calculation is focused on emissions from activities related to the production of goods and services throughout their entire life cycle.

The PAS 2050 method establishes six large groups of activities that occur during the life cycle of goods and services, whose emissions must be considered in the estimation.

The PAS 2060 method, published in 2010, is a variation of the PAS 2050 to calculate the emissions generated at the level of organizations, territories and individuals.

Composite method of ledger accounts

The composite method of ledger accounts can be applied to both companies and products. It allows using the data from the accounting accounts as possible sources of carbon emissions, allowing the economic aspect to be related to the environmental one.

It takes into account the emissions generated in an organization, without exceeding its own limits, therefore it does not include emissions from customers, suppliers, consumers or from the disposal of the product at the end of its useful life.

Unlike the other methods, this indicator allows the calculation of both the carbon footprint, in tons of CO2 per year, and the ecological footprint, measured in land area.

How to reduce it?

The greenhouse gases generated by the use of fossil energy are the main factor causing climate change and the increase in the planet's temperature, with profound ecological, social and economic impacts.

Below are some urgent actions to promote a reduction in emissions globally. However, the only change that can generate any real impact on global warming and climate change is a radical shift in consumption patterns and in the life patterns typical of modern industrialized societies.

Reduction of energy consumption

Transportation of local food. Source: www.pixabay.com

To achieve a reduction in the global carbon footprint, it is imperative to achieve a reduction in energy consumption, with the burning of fossil fuels being one of the main causes of greenhouse gas emissions.

The sectors that have the highest energy demand are industrial, transport and residential. Thus, the energy consumption of these sectors should be reduced to reduce the global carbon footprint.

The transport sector, based on the use of individual cars and the distribution of goods by land, sea and air, contributes tons of greenhouse gases into the atmosphere.

Some alternatives that would help reduce the carbon footprint would be the electrification of most modes of transport, improvements in the efficiency of fuel use and the development of new fuels.

However, no alternative can support current usage / consumption patterns. A reduction in the carbon footprint requires changes in lifestyle, which prioritize electric public transport and fast trains over private vehicles and airplanes.

Likewise, the consumption of local products should be prioritized over imported ones, which travel thousands of kilometers between the producer and the consumer.

Decarbonization of the energy systems

Wind power. Source: Z22

Fossil fuels represent 80% of the total primary energy used. To achieve a significant reduction in the carbon footprint, this consumption must be reduced to a maximum of 20 or 30%.

This reduction implies that the use of fossil fuels must be replaced by other renewable energy sources, such as wind and solar energy. The cost of this technology has decreased in recent years, making it a feasible alternative to fossil fuels.

Another way to decarbonize energy can be a combination of the use of fossil energy combined with carbon capture and storage, this option being the most feasible in most scenarios.

Reducing net emissions and enhancing carbon sinks

Reforestation project. Source: Juan Antonio Pellicer Alcaraz

Reducing the carbon footprint can also be achieved through the active removal of CO2 from the atmosphere. Reforestation and the use of bioenergy can reduce CO2 levels in the atmosphere.

However, both are limited by the amount of land available (required for food production) and by environmental and social impacts. Also, these alternatives have very limited potential for CO2 storage.

On the other hand, CO2 sequestration in geological formations has also been evaluated. This method has the necessary capacity to store large amounts of greenhouse gases, which would allow their atmospheric concentrations to be significantly reduced.

However, there are significant risks associated with permanent storage, such as environmental contamination from leaks and seismic activities.

Examples

Carbon footprint of developed countries

The carbon footprint in developed countries is significantly higher than in undeveloped countries. 75% of global emissions are produced by only 10 countries.

Likewise, the monthly rate of emissions per capita in rich countries is much higher than the annual emissions per capita in poor countries.

This great difference is based on the industrialization of the production of goods and services, and on the consumption patterns and lifestyle of developed societies and the world's elites.

Carbon footprint in food

Imported food has a higher carbon footprint than local food. Transportation (maritime, land or air) requires fossil fuels that generate greenhouse gases.

Foods grown under industrial agriculture have a higher carbon footprint than those produced agroecologically. Industrial agriculture has a high demand for fossil fuels for machinery for planting, harvesting, transporting, processing and storing production.

The carbon footprint of animal protein produced under intensive and industrial breeding patterns has a higher carbon footprint than plant foods. On the one hand, to raising livestock must be added the carbon footprint of the feed, which could be destined for people. On the other hand, livestock produce methane, one of the greenhouse gases.