Net zero: more questions than answers

In connection with the Paris Agreement, many its participant states have pledged to achieve carbon neutrality by some year in the middle of this century. Carbon neutrality means that all anthropogenic emissions of carbon dioxide or other greenhouse gases (GHGs) are offset by projects that absorb carbon dioxide from the atmosphere. These projects may be related to planting or maintaining forests, or GHG capture and storage technologies, or more efficient and sustainable agricultural practices.

Ideally, a country as a whole or a separate company, while pursuing a course towards net zero, shall work in two directions – reducing GHG emissions and offsetting them with the help of third-party projects. Offsets shall come second, while the reduction of GHG emissions shall have the top priority. However, it turns out in practice easier and much cheaper to “pay off” with offsets rather than to transform the production system.

Markets for trading carbon offsets are rapidly evolving. Unfortunately, having bought the necessary amount of such offsets, a corporation or a country can legally continue to emit greenhouse gases without worrying about reducing these emissions and about the future climate on the planet.

The first problem with this offsetting system is just common fraud. Back in 2010, the Christian Science Monitor found out that a company the Vatican worked with to offset its carbon emissions took money promising to plant trees, but never did it.

There may be blunt lies in reports of compensatory projects. One can meet media messages about how a company planted so many thousands of trees and thereby offsets its GHG emissions. A simple calculation sometimes shows that each such tree must absorb and store several hundred kilograms of carbon per year. Trees with such properties are unknown to science.

It is also important to remember that the planted young forest absorbs carbon from the atmosphere not ever, but only until it reaches maturity, an equilibrium state, in which the carbon dioxide and methane emissions equal their absorption.

In addition, the compensatory potential of ecosystems cannot be measured at all, and is very difficult to calculate. Therefore, big errors are possible when implementing compensatory projects. For example, thousands of hectares of peat bogs were drained to plant trees in Scotland. It was subsequently calculated that this released much more carbon into the atmosphere than the newly planted trees could hold.

Forests are often planted in third world countries. It is known that such projects can and do violate human rights in the places of their implementation. However, the issues of problems for the local population are not taken into account.

Obviously, new forests will be able to absorb not more carbon from the atmosphere than has been emitted in the entire history of their destruction. This is several times less than the amount of carbon that has been buried in geological formations over millions of years in the form of fossil fuels and emitted into the atmosphere during its combustion over the past couple of centuries.

Thus, the concept of carbon neutrality in the form how it is now understood and used by most companies and countries looks rather similar to the medieval purchase of indulgences.

Another danger of playing with net zero is the temptation to use geoengineering techniques to achieve it. Geoengineering is measures and interventions aimed at actively combating climate change. Most of these technologies are aimed at reducing solar radiation reaching the Earth (while the content of carbon dioxide in the atmosphere does not decrease). These projects include spraying aerosols in the stratosphere to reduce solar radiation on the Earth’s surface, injecting seawater into the atmosphere to increase clouds’ density and thus their reflectivity, spraying fresh water over the Arctic to create a thick surface layer of ice, since seawater is less prone to freezing, and even shading of solar radiation by objects in space.

Among projects aimed at reducing the concentration of carbon dioxide in the atmosphere, one can mention saturation of oceans with iron ions in order to stimulate photosynthesis by phytoplankton, increasing soil biomass and increasing plant biomass in arid zones. The final effects of all these technologies are not fully understood, the processes can become ineffective, unstable, or even lead to deterioration of the ecological situation.

More innocuous geoengineering projects include plans to change the Earth's albedo by painting roofs of buildings white to reflect solar radiation or switching to crops that increase the albedo of fields. However, the potential impact of such measures is small and the economic costs are high.

Friends of the Earth International have published a briefing note for COP 26 in Glasgow about problems related to net zero plans. It can be found here.

Olga Senova, Head of the RSEU Climate Secretariat, believes: “All countries, municipalities, companies and organisations must make significant efforts to urgently reduce greenhouse gas emissions. Greenhouse gas offset projects should have low priority, be applied in a scientifically sound manner, and pay respect to human rights in locations of their implementation. Dangerous and untested geoengineering technologies should be completely excluded from all plans."