COP26 - The attempt to control the Earth's greenhouse

"The future of the Earth, as we know it, is dependent on the slowdown in carbon dioxide emissions"

The Conferences of the Parties to the United Nations Framework Convention on Climate Change (COP) had its genesis in the Earth Summit held in Rio de Janeiro in 1992 (Rio Convention).

COP1 took place in Berlin in 1995, when the concentration of carbon dioxide in the atmosphere was around 361 ppm. In 2021, the year of COP26 in Glasgow, the concentration of carbon dioxide in the atmosphere has already risen to 419 ppm (an increase of 16% compared to 1995).

The Earth's future, as we know it, is dependent on the deceleration of carbon dioxide emissions, and in general of greenhouse gases (GHG), leading to the stabilization of its concentration in the Earth's atmosphere and progressive decrease.

Only then, the Earth's average temperature will remain at values ​​that do not lead to disruption of its climate.

It should be remembered that, in 2015, at COP21 in Paris, the objective was set to observe an increase in the Earth's average temperature of less than 2°C in 2100 and, preferably, limit this increase to 1,5°C, relative to the temperature before the industrial era (average temperature in the years 1850 to 1900). However, the total increase in the temperature of the Earth's global surface between the pre-industrial era and the last decade is already around 1,1 °C!

At COP26, some commitments were made to control the increase in the Earth's temperature.

In Europe, expectations were high for this conference. In fact, at the end of the first half of 2021, the European Climate Law was approved, which agreed to reduce GHG emissions by at least 55% by 2030, compared to 1990 levels, and that Europe will be carbon neutral. in 2050.

In Germany, an even more ambitious commitment was defined: to reduce GHG emissions by at least 65% by 2030 and reach carbon neutrality in 2045. Very recently, in Portugal, the Basic Climate Law was approved, which recognizes the climate stable as a Common Heritage of Humanity. In fact, the generation of Millennials, and those that will follow, will only live on a planet with a stable climate if urgent measures are taken to protect it, which can only be achieved by significantly reducing GHG emissions.

Burning coal is a major contributor to global carbon dioxide emissions. For this reason, at COP26, one of the proposals was the programmed withdrawal (Phase out) of the use of this fossil fuel.

In the last minutes of the conference, and in opposition to India, the phrase that was in the text of the almost final agreement “end of its use” (Phase out) was replaced by “reduction of its use” (Phasedown).

However, for the first time at a COP, there was explicit recognition of the use of coal and other fossil fuels as the main drivers of climate change.

Currently, India, which is the largest democracy in the world, has the worst air quality in its cities, deteriorating the quality of life of its population and causing millions of premature deaths, so commercial/economic pressures should be exerted on a country with this type of environmental policy.

On the other hand, South Africa, with an economy very dependent on coal, reached an innovative agreement for an energy transition towards decarbonisation, in partnership with France, Germany, United Kingdom, USA and Europe.

In parallel to COP26, several initiatives were carried out to protect the Earth's climate by groups of countries, such as the “Global Commitment on Methane” proposed by the USA and Europe, to which more than 100 countries voluntarily joined. This commitment corresponds to a 2020% reduction (compared to 30) in methane emissions by 2030.

However, the main countries that emit methane into the Earth's atmosphere, such as China, India and Russia, were left out. Methane, related to the exploitation of fossil fuel gases, such as natural gas, and to agricultural activity, is a GHG that has a warming potential of about 30 times greater than carbon dioxide.

Bad agricultural practices and the lack of agro-environmental management have made agriculture one of the activities with the highest GHG emissions: carbon dioxide, methane and also nitrous oxide. Excessive use of fertilizers in agriculture gives rise to nitrous oxide emissions, which have a warming potential of about 280 times that of carbon dioxide.

COPs, or parallel initiatives, have made commitments to the development of sustainable agriculture. At COP26, 26 countries pledged to change their agricultural policies, making them more sustainable and less polluting. For example, Brazil plans to increase its low-carbon agriculture program to 72 million hectares, reducing carbon dioxide emissions by 1 billion tons by 2030.

At this event, another particularly important initiative for the Earth's climate was the “Declaration on Forests and Land Use”, taken on by 134 countries responsible for 91% of the world's forests.

The goal is, by 2030, to stop deforestation and land degradation. Now, the most efficient natural mechanism to remove carbon dioxide from the atmosphere is the photosynthesis of plants, which transforms it into plant biomass. The longer the plant life cycle, the greater the carbon sequestration.

The destruction of forests is, for this reason, an environmental drama. Each tree is always sequestering a large amount of carbon dioxide while it is alive and, once it is dead, returns to the atmosphere most of what it stored while growing.

In addition, deforestation exposes bare soil to atmospheric oxygen, increasing the oxidation of soil organic matter (MOS) with emission of carbon dioxide – MOS is another major store of carbon dioxide sequestered from the Earth. In this context, this declaration is most welcome, but it is long overdue! There is no justification for still continuing to commit these types of atrocities to Earth today.

One of the most symbolic conclusions of COP26 was the formal recognition of the need to reduce global carbon dioxide emissions by an impressive 45% by 2030, compared to 2010, significantly reduce other GHGs and even reach carbon neutrality by mid-century. These goals are necessary to maintain the limits of temperature increase on Earth set at COP21 in Paris.

However, the latest calculations, based on the countries' current GHG emissions plans, point to an increase in the Earth's temperature of approximately 2,4 °C by the end of the century, which would lead to a disruption of the current climate.

In order to try to control this problem, and thus maintain the Paris Agreement, countries were invited to present, until the next COP, in 2022, new values ​​for their GHG emissions and emission reduction strategies (the so-called NDC - NationallyDeterminedContribution).

In 1987, faced with the threat of the destruction of the ozone layer by chlorofluorocarbons (CFCs), and the consequent elimination of life from the Earth's surface, all the countries of the Earth united around the Montreal Protocol to prohibit the use of CFCs. Right now, the Earth urgently needs a new “Montreal Protocol”, but this time for the reduction of GHG emissions. We hope that the next COP will make a more significant contribution to this goal of Earth survival as we know it today.


Author Joaquim CG Esteves da Silva
Faculty of Sciences of the University of Porto