WikiCarbon #1: Definition, relationship with climate change and CO₂e

Fundamental concepts you need to know to follow decisions, advances, and discussions about the carbon economy. Every week, three concepts and a challenge. Join us!

With the aim of democratizing information, access, and discussions, we at YangPlanet have created more than just a glossary in our carbon ecosystem.

The Carbon Wiki is a collaborative space for defining concepts that need to be leveraged so that society can contribute to the discussion of the carbon economy.

You can send suggestions, request our science team for a definition, or propose an adjustment (just comment on the posts or send suggestions to wiki@yangplanet.com). Shall we build a definitive and collaborative guide for society to understand and build the carbon economy?

1. What is CARBON? 

Carbon is a chemical element with atomic number 6 — meaning it has 6 protons and 6 electrons — and an atomic mass of 12. It is the sixth most abundant element in the universe and ranks 15th in abundance in the Earth's crust, making it common but far from trivial. Its main characteristic is tetravalency: it can form up to four covalent bonds with other atoms. This property gives it unique versatility, allowing it to compose a vast array of molecules — from the simplest to the most complex. 

Carbon is present in almost everything. In inorganic molecules, like methane (CH₄) and carbon dioxide (CO₂). In complex organic molecules, like glucose (C₆H₁₂O₆). In all living beings — as each cell carries carbon in its fundamental structure – and carbon is in proteins, carbohydrates, lipids, nucleic acids (like DNA)...

In other words: life is a carbon arrangement. Laughter.

But it also exists outside living organisms. Carbon appears in the atmosphere, as CO₂ and CH₄ (methane); in water, dissolved as carbonic acid (H₂CO₃) or bicarbonate (HCO₃⁻); in fossil fuels, such as oil and natural gas; in minerals, like chalk, coal, marble, graphite, and diamond; in limestone rocks, like limestone and dolomite, formed by carbonates.

These manifestations vary greatly in their dynamics: some are extremely stable, like minerals and carbonated rocks, while others are highly mobile, like atmospheric gases and organic compounds in plants. The difference between static and dynamic carbon is essential to understand how the carbon cycle works and why it is so central to discussions on climate, energy, and land use. Want to know more? Click here.

2. WHY CARBON? 

Why do we talk so much about carbon when discussing climate change — or how can an element that represents less than 0.05% of the atmosphere have such an impact on the planet? The answer is simple: its prominence in the greenhouse effect. 

The Earth's atmosphere is mainly composed of nitrogen (78%) and oxygen (21%). Carbon dioxide (CO₂), in turn, represents only 0.04% of the atmospheric volume — a tiny fraction. Even so, it is one of the main gases responsible for the greenhouse effect, helping to maintain the Earth's surface temperature within a range that allows life.

The greenhouse effect is a natural and necessary phenomenon. The problem begins when we add excess CO₂ — and that is exactly what we have been doing through the burning of fossil fuels (coal, oil, natural gas) for energy generation; and through deforestation, which releases carbon stored in trees and soils and reduces the removal capacity via photosynthesis.

Historically, the concentration of CO₂ in the atmosphere remained stable at around 280 parts per million (ppm) for thousands of years. But since the Industrial Revolution, this concentration has been increasing and reached 422 ppm in 2024. This jump of more than 50% happened in less than three centuries — a blink of an eye in geological terms — and is directly linked to global warming and the climate changes we are already experiencing, and the concept of Anthropocene. Read more.

3. CARBON MARKET - What is CARBON EQUIVALENT (CO₂e)?

Following this logic, the carbon market was developed after the Kyoto Protocol (1997), as a system for compensating and/or trading greenhouse gas (GHG) emissions, especially carbon dioxide (CO₂), designed to encourage companies and countries to reduce their emissions or invest in solutions that remove carbon from the atmosphere. 

CO₂ was adopted as the standard unit because it is the most emitted greenhouse gas globally, with a long lifespan in the atmosphere (up to 100 years), and because it is easily measurable. To standardize the emissions of different gases, the metric carbon dioxide equivalent (CO₂e) was created — which converts gases like methane (CH₄) and nitrous oxide (N₂O) into a comparable basis.

The carbon market consists of buying and selling credits to offset pollution liabilities. For example, an environmental project that reforests deforested areas or preserves nature helps prevent CO₂ from reaching the atmosphere – this is called carbon sequestration. This carbon sequestration is transformed into credit that can be traded. On the other side of the market, companies that maintain economic activity contributing to CO₂ emissions can buy the credits, thus achieving environmental compensation. Want to know more? Read here.

#BEYANG CHALLENGE

Now that you have navigated through the basic definitions, in your perception, which professionals are involved in the carbon economy? 

Send your response in the comments or on our social networks and contribute to the collaborative encyclopedia. Next week, Rafael Mezzomo, co-founder and technology leader at YP, will bring a perspective on the carbon market – and will bring us his response to this challenge. 

See you next week!!