In CO2 neutrality, the amount of CO2 emitted matches the amount of CO2 removed from the atmosphere over a defined period of time. In other words, the CO2 emitted by a particular activity, product, creature or other is offset by the removal and/or uptake of CO2 from the atmosphere over the defined period, resulting in a neutral balance. This is also referred to as "net zero CO2 emissions", since the bottom line is "zero" CO2 emissions.
If more CO2 is eliminated than emitted, we speak of negative emissions, "net negative emissions" or a positive CO2 balance.
Emissions and their elimination often occur independently of location, since the CO2 balance of a product, for example, relates to its global balance. This is the case because carbon dioxide, unlike other harmful substances in the atmosphere, is a pollutant that mixes uniformly. This means that the gas is distributed very quickly and evenly over the entire surface of the earth, so that it is no longer immediately relevant at which specific location the emissions or reductions take place.
A CO2-neutral product is often also referred to as a climate-neutral product. Here, however, it is important to know that there are essential differences in the two concepts. This confusion may be related to the fact that the English word "carbon-neutral" can be translated into German as both CO2-neutral and climate-neutral.
First and foremost, it should be checked how the CO2 emissions of a product, process or service can be reduced before offsetting the emissions elsewhere. Accordingly, if a product is CO2-free, no emissions would have to be offset because none are produced.
However, for a product, company or service to be CO2-free, this would have to cover the entire value chain, including production, extraction of raw materials, sales and, if necessary, disposal, which would be nearly impossible to achieve.
The definition for greenhouse gas neutrality ("Green House Gases (GHG)", is identical to CO2 neutrality, except that all greenhouse gases are included here.
The primary greenhouse gases in the Earth's atmosphere according to the IPCC are water vapor (H2O), carbon dioxide (CO2), nitrous oxide, also known as laughing gas (N2O), methane (CH4), and ozone (O3). Under the 1987 Montreal Protocol and the 1997 Kyoto Protocol, additional greenhouse gases are also addressed, including those that are entirely man-made.
What makes greenhouse gases so harmful to the climate?
The sun's rays hitting the earth pass through the atmosphere, which consists of many (necessary) greenhouse gases. Some of the sun's rays are reflected directly back into space, and some are absorbed by the surface, e.g. forest or ice cover. The greenhouse gases in turn intercept part of the sun's rays that are reflected back and thus provide the necessary, pleasantly "warm" temperature that makes life on Earth possible. They therefore prevent all the sun's rays from being reflected back again without warming. Simply put, because of greenhouse gases, a significant portion of the sun's rays are kept in the atmosphere in the form of heat. However, if the concentration of greenhouse gases in the atmosphere increases to an unusually high level, e.g. due to excessive anthropogenic emissions, the temperature of the Earth will consequently also rise.
This is then referred to as the "anthropogenic greenhouse gas effect", which is caused by human activities such as the burning of fossil fuels for energy production, transportation, or agriculture.
The concept of climate neutrality describes the state in which human activities have no effect (neither positive nor negative) on the Earth's climate system. This implies that man-made emissions (of all harmful substances) are removed and thus neutralized, and that in addition responsibility is taken for the regional and local natural effects of human activities, for example on the local climate.
The causal determination between climate change and anthropogenic action is very complex and difficult to quantify. The extent to which a particular activity is responsible for an extreme flooding event, for example, is subject to large uncertainties. In addition, concrete estimates are complicated by natural climate variations that have always existed on Earth.
For the same reason, it is also difficult for companies to determine their exact natural and climatic impacts. Therefore, it is all the more important to reduce greenhouse gases because they are quantifiable and easier to identify.
Nowadays, there are many ways to mitigate greenhouse gases.
For CO2, one of the best-known methods here is reforestation. Trees and plants perform photosynthesis and can thus bind CO2 from the air and produce vital oxygen at the same time. Increased use of renewable energy sources is another way to reduce CO2 emissions. More modern techniques such as carbon capture and storage can be used to capture CO2 and store it underground before it is emitted. However, these and similar processes are still undergoing extensive research and are technically more complex.