Glossary | Climate Lexicon C

carbon-connect AG Climate Glossary with common technical terms, abbreviations and explanations on the topics of the environment, climate protection and CO2 compensation.

Carbon Accounting

Carbon accounting is the systematic recording of CO2 and other greenhouse gases. Companies, the public sector, and organizations thus create a greenhouse gas balance (CO2 balance). Carbon accounting is usually part of environmental and sustainability management.

Carbon Capture and Storage / CCS

Carbon capture and storage (CCS) is a technology in which CO2 is captured from industrial processes or power plants and then safely stored in underground reservoirs or under the seabed to prevent its release into the atmosphere. This is intended to help reduce greenhouse gas emissions and combat climate change.

Carbon Dioxide Concentration

Carbon Dioxide Concentration refers to the amount of carbon dioxide present in the atmosphere. Carbon dioxide is a greenhouse gas that is released into the atmosphere through human activities such as burning fossil fuels for energy, deforestation, and industrial processes. The increase in carbon dioxide concentration in the atmosphere is one of the main drivers of climate change, as it traps heat from the sun and causes global temperatures to rise. The concentration of carbon dioxide in the atmosphere has increased dramatically since the industrial revolution and is now at a level not seen for millions of years. Reducing carbon dioxide concentration is a critical aspect of mitigating the impacts of climate change. Carbon dioxide concentration is measured in ppm (parts per million).

Carbon Market Watch

Carbon Market Watch is a non-profit organization focused on monitoring and enforcing action on emissions reductions and trading in greenhouse gas emissions (carbon markets). It works closely with governments, businesses, and other stakeholders to ensure that greenhouse gas emissions trading is effective and equitable and that emissions are actually reduced. It also has a platform and resources for the public and civil society to learn about carbon market developments and actively participate in the discussion. Carbon Market Watch is an independent think tank and NGO that advocates for effective and equitable regulation of the carbon markets.

CC (Corporate Citizenship)

Is part of the social responsibility of companies to solve social problems within the direct and local sphere of a company.

CDM (Clean Development Mechanism)

The Clean Development Mechanism is one of three flexible mechanisms for reducing greenhouse gases and has its origins in the Kyoto Protocol. The main objective of the CDM is to help developing countries fight climate change and promote sustainable development. The CO2 emissions saved in related projects in developing countries are subsequently credited to the industrialized countries.

CDM Gold Standard

The CDM Gold Standard refers to CO2 reduction projects with a particularly high quality taking place in developing countries. Not only ecological are important. Social criteria play an important role here in ensuring a sustainable development.

CDP (Carbon Disclosure Project)

The Carbon Disclosure Project (CDP) was founded in the year 2000 as a non-profit organization in London. The goal of CDP is to encourage businesses and the public hand to disclose environmental data, including climate-damaging greenhouse gas emissions as well as water consumption. The survey is conducted by means of an annual standardized questionnaire. Up to now, over 800 institutional investors have been participating in this annual survey.

CERs (Certified Emission Reductions)

Certified Emission Reductions, or Certified Emission Reduction Credits. 

Certified Emission Reductions (CERs) are allowances issued under the Clean Development Mechanism (CDM) of the Kyoto Protocol. The Kyoto Protocol is an international agreement to reduce greenhouse gas emissions.

CERs serve as evidence of successful greenhouse gas emission reductions in developing countries and can be purchased by developed countries as part of their emission reduction commitments. CERs provide a flexible way for developed countries to meet their emissions targets by investing in emissions reduction projects (climate protection projects)  in developing countries, rather than reducing emissions directly in their own countries.

The goal of CERs is to encourage the transfer of technology and financial resources from developed to developing countries to support emissions reductions and the transition to a more sustainable economy. However, there are also criticisms of CERs, particularly regarding their effectiveness and transparency, and it is argued that they are not sufficient to achieve the Kyoto Protocol's goal of limiting global warming.

CFC / Hydrofluorocarbon

CFCs or chlorofluorocarbons are among the longest lasting greenhouse gases and lead to global warming. The first CFC-free refrigerator was manufactured in 1992. Since the year 2000, household and commercial refrigerators are produced with a new, different refrigerant. The mixture consists of propane and butane and does not increase the greenhouse effect, but unfortunately, it is flammable.


Climate refers to the average state of a region's weather over at least 30 years. It describes the temperatures, precipitation, winds, and other meteorological conditions that prevail in a given region over an extended period of time. A region's climate is influenced by several factors, including geographic location, elevation, proximity to the sea, and the presence of mountains. Climate change refers to long-term changes in climate caused by human influence on the atmosphere, mainly by the increase in greenhouse gases.

Climate Compensation

Cliamte compensation (carbon offsetting) refers to the compensation of greenhouse gas emissions from a product or an activity. This can be achieved by reducing emissions or offsetting emissions by investing in climate-friendly projects. The idea behind is to balance out the negative impact on the environment by taking actions to reduce the same amount of emissions elsewhere. This can be done through measures such as planting trees, investing in renewable energy, or supporting carbon capture and storage technology. The goal of it is to neutralize the carbon footprint of an individual, business, or event, and to help reduce the overall impact of human activity on the environment.

Climate Protection Project

A climate protection project reduces greenhouse gases by replacing fossil fuels with renewable energies. This happens when a coal power plant will be replaced by a wind farm to generate electricity, for example. The mechanism originates from the Kyoto Protocol for the reduction of greenhouse gases, and is an instrument for effective climate compensation. The most common climate protection projects are permanent CO2 indents, which are arranged through afforestation or renewable energy projects (e.g.: wind turbines, solar plants, hydropower projects).

Climate System

The climate system consists of various subsystems, which interact with each other. The climate system consists of five main components: the atmosphere, the hydrosphere (oceans, rivers, lakes), the cryosphere (ice and snow), the biosphere (on land and in the ocean), and the pedosphere and lithosphere (soils and solid rock). The climate system is changes from time to time. This change can be sparked by external causes (volcanic eruption) or by an internal dynamic.

climate tipping points

The 16 known climate tipping points identified by scientists are:

  • melting of Arctic permafrost
  • melting of glaciers and ice sheets
  • destruction of forests
  • Ocean acidification
  • the shifting of rainfall patterns
  • the change of ocean currents
  • the change of cloud cover
  • the change of the ozone layer
  • the change of vegetation
  • the change of the water cycle
  • the change of the soil
  • the change of sea ice cover
  • the change of sea ice cover in the Arctic
  • the change of sea ice cover in the Antarctic
  • the change of sea ice cover in Greenland
  • the change in sea ice cover in other parts of the world.

It is important to note that these tipping points are interrelated and the effects of one tipping point can often amplify the effects of other tipping points. To avoid or minimize these tipping points, it is important to reduce greenhouse gas emissions and support adaptation measures.


Climateology is the science of the following disciplines: meteorology, geography, geology, oceanography, and physics. Climateology explores the regularities of the climate.

Corporate Carbon Footprint

A corporate carbon footprint is a measurement of the total emissions of greenhouse gases generated by a company or organization, including direct emissions from fuel combustion and indirect emissions from the use of electricity, heat and materials. It refers to the entire life cycle of a product or service, from manufacturing to transportation, use, and disposal. The Corporate Carbon Footprint serves as a tool for companies to monitor and reduce their environmental impact and fulfill their responsibility for climate protection.

CO2 Budget

The CO2 budget refers to the limited amount of carbon dioxide emissions that can be released into the atmosphere to avoid dangerous global warming. This budget is determined based on the total amount of emissions that can be released into the atmosphere without jeopardizing the Paris Agreement goal of limiting the global temperature increase to well below 2 degrees Celsius and efforts to limit the increase to 1.5 degrees Celsius.

The CO2 budget is calculated based on the total amount of emissions generated and the remaining amount of emissions that can be released to meet the temperature limit. The budget is updated on an ongoing basis.

The exact date when the CO2 budget will be reached is uncertain because it depends on a variety of factors, including policy decisions to reduce emissions, global energy and economic trends, and technological advances in renewable energy and emissions reductions.

Some studies predict that the CO2 budget could be reached in the coming decades if global CO2 emissions (carbon emissions) continue to rise unabated.

CO2-eq / CO2 equivalent / Carbon Dioxide Equivalents

CO2 equivalent (CO2-eq) is a unit of measurement used to compare the impact of different greenhouse gases on climate change. Since different greenhouse gases have different warming and climate impacts, they are converted to CO2 equivalents to allow for comparability. A CO2 equivalent is an amount of a greenhouse gas that has the same warming impact as a given amount of CO2. The use of CO2 equivalents allows the total emissions of different greenhouse gases to be quantified and compared. The main greenhouse gases and their CO2 equivalent include:

Greenhouse gas:                                                             CO2 equivalent:

Carbon dioxide                                                                1

Methane (CH4)                                                                25

Nitrous oxide / nitric oxide (N2O)                                 298

Fluoroform (HFC-23)                                                      14800

Sulfur hexafluoride (SF6)                                                22800

carbon neutrality

Carbon neutrality means that the amount of carbon dioxide (CO2) emitted by a particular product, company or activity is offset by other activities. This process is referred to as carbon neutrality or CO2 neutral. Examples of carbon neutral activities include financing renewable energy such as wind and solar, protecting forests and reforestation projects, or promoting energy efficient technologies. A CO2 emission at location A is offset by financing a climate protection project at location B.

CO2 Indents

CO2 sinks are ecosystems that permanently absorb or store CO2, such as peatlands, soils, forests and oceans. In general, any ecosystem that absorbs more CO2 than it releases is called a CO2 sink. The Southern Ocean accounts for just a quarter of the total ocean area, but absorbs 40% of the man-made CO2 emissions absorbed by the world's oceans. Forests are the second largest CO2 sink on our planet.

CO2 Certificate

CO2 certificates are a volume unit for emissions that are compensated. One CO2 certificate equals to one ton of CO2. CO2 certificates are a unit of quantity of emissions that are offset. One CO2 certificate is equivalent to one ton of CO2. A CO2 certificate is a document that certifies that a certain amount of greenhouse gas emissions has been avoided or reduced. It is part of an emissions trading system in which companies are allowed to emit a limited amount of emissions and any surplus can be exchanged on the market for other emission rights or certificates. Certificate trading creates an economic incentive to reduce greenhouse gas emissions. A CO2 certificate can also be used as proof of a climate-neutral business practice.

Compensation Services

Various companies appear on the market as compensation services, and offer the neutralization of products, processes, services, companies and events. Products, processes or companies whose emissions are fully compensated are denoted as climate-friendly or climate-neutral. In Europe, companies have the biggest demand for compensation services. They help to reduce the carbon footprint of a company, individual products, or specific processes such as business trips or the fleet(vehicles).

CORSIA Agreement

CORSIA (Carbon Offsetting and Reduction Scheme for International Aviation) is a global agreement under the International Civil Aviation Organization (ICAO) aimed at offsetting CO2 emissions from international aviation. It is a market-based approach where airlines can purchase carbon credits to offset emissions that exceed a set baseline. The agreement became effective in 2021 and will run until 2035, with the goal of achieving carbon-neutral growth in international aviation from 2020.

CSR (Corporate Social Responsibility)

Corporate Social Responsibility describes the voluntary contribution of the economy to developments which are sustainable. This term stands for responsible corporate behavior and includes environmentally relevant aspect, a company’s relationships with employees and suppliers, as well as with its stakeholders. It is a voluntary contribution by companies that goes beyond legal requirements and compliance. Since 2020 the term ESG has established.

CSRD / Corporate Sustainability Reporting Directive

The Corporate Sustainability Reporting Directive (CSRD) is a European Union (EU) legislation aimed at promoting greater transparency and accountability of large companies in terms of their sustainability performance. The Directive aims to enhance corporate sustainability reporting by requiring companies to disclose information on environmental, social, and governance (ESG) matters, such as greenhouse gas emissions, human rights, and bribery and corruption. The CSRD is part of the EU's broader efforts to promote sustainable business practices and support the transition to a low-carbon, circular economy.