We have reached a new carbon dioxide record

According to the latest data released today by the World Meteorological Organization, in 2018 the concentration in the atmosphere of carbon dioxide, the main gas responsible for the greenhouse effect, has reached a new record: 407.8 parts per million (ppm), against the 405.5 parts per million of 2017. The increase is higher than the average increase of the last decade, a signal that could indicate that the concentration of carbon dioxide is increasing faster than in the past. "Despite the commitments made during the climate conference in Paris," said the organization's secretary, Petteri Taalas, "for the moment there is no sign of slowing down, not to say diminishing, in the concentration of greenhouse gases in the 'atmosphere".

Carbon dioxide, or CO_2, it is the main greenhouse gas present in the earth's atmosphere and is naturally produced by volcanoes, animals and humans. The problem is that over the last century and a half, the enormous quantity of carbon dioxide produced in the combustion processes of oil and coal has been added to these natural sources. Together with the other greenhouse gases, this CO₂ present in the atmosphere prevents the Earth from dispersing some of the heat from the Sun, with a consequent increase in temperatures and the so-called "global warming".

For this reason, for decades the UN and the main international scientific organizations have been asking governments around the world to agree to implement policies that reduce CO production.₂, passing from the use of fossil fuels for the production of energy to renewable sources, which entail a lower production (in some cases almost equal to zero) of carbon dioxide. The main agreement reached so far is the Paris agreement of 2015, which commits all underwriting countries to reduce the increase in emissions so as to limit the temperature increase by 2100 to 1.5 degrees Celsius .

The concentration of CO₂ in the air is one of the main factors that will influence how the temperature will increase over the next few decades. To calculate it, the World Meteorological Organization uses data collected from a dozen measurement stations around the world. The oldest and most famous observatory that provides this data is that of the Mauna Loa volcano in Hawaii. Activated in 1958, the first survey of the station resulted in 315ppm (almost a hundred parts less than the current level). The scientist who initiated the measurement, Charles Keeling, today named after the "Keeling curve", the main measurement of the increase in CO concentration₂ in our atmosphere.

It is estimated that the current concentration of carbon dioxide is more than 147 percent higher than the concentration of 1750, the date usually used as the end of the pre-industrial era. The last time the planet had reached such a level of concentration, about 3 million years ago, the earth was 2-3 degrees warmer than today and the seas were 10-20 meters higher.

The concentration of CO₂ it is in turn the product of carbon dioxide emissions, or rather the result of the complex relationship between the combustion of hydrocarbons and other polluting sources and a series of complex atmospheric phenomena. About half of the CO₂ produced in the world is absorbed by the oceans and forests; the rest remains in the atmosphere, helping to increase concentration levels and therefore temperature.

At the Paris climate conference, almost all the countries of the world committed themselves to reducing their emissions, but the data published today show that the facts are not always followed by promises. In the coming months, the United Nations should publish a new report highlighting the gaps between the promises of intervention made at the Paris conference and the measures actually taken. According to the advances already published, despite the commitments the polluting emissions would have continued to grow overall also in 2018.