Global lockdown measures for COVID-19 will barely make a notch in the steep growth curve of atmospheric concentrations of carbon dioxide, the cause of climate change.
And the stoppage of the world economy will not imply a reduction in the accumulation of gases that overheat the planet, the World Meteorological Organization (WMO) pointed out this Monday.
This will mean that in 2020 record levels will be set again.
This organization, linked to the UN, has virtually presented the annual newsletter on the evolution of the three main greenhouse gases: carbon dioxide, methane and nitrous oxide.
Although the document focuses on the closed data for 2019 - when atmospheric concentrations of these three gases rose again - the WMO has already offered some estimates for this year 2020.
The agency recalls that preliminary calculations indicate that human emissions of carbon dioxide will be reduced by between 4.2% and 7.5% this year, although the uncertainty is great because it is yet to be known whether Landfills become more stringent in the final stretch of 2020. In any case, the WMO maintains that, "on a global scale, a reduction in emissions of this magnitude will not reduce the concentration of atmospheric carbon dioxide."
It will only make the concentration rise "at a slightly slower rate."
This slowdown will be similar to "normal fluctuations in the carbon cycle that occur from one year to the next."
In other words, in the short term "the impact of the confinement measures applied as a result of COVID-19 cannot be differentiated from natural variability," explains the WMO.
About half of the carbon dioxide that humans emit ends up accumulated in the atmosphere (the other half is captured by vegetation and the oceans).
Then that gas remains concentrated in the atmosphere for hundreds of years.
Anthropogenic emissions have been growing since the 18th century, since pre-industrial times.
And in recent decades that increase has been accentuated.
The rate has been such that "the last time a comparable concentration of carbon dioxide was recorded on Earth was between three and five million years ago," Petteri Taalas, WMO Secretary General, said Monday.
The accumulated historical emissions together with the permanence of this gas for centuries in the atmosphere partly explain that the confinements that have led to specific reductions in emissions (non-structural) are hardly going to be perceived in atmospheric concentrations.
The WMO bulletin explains that only when the emissions generated by the burning of fossil fuels approach zero will it be possible to begin to reduce the concentration of this greenhouse gas in the atmosphere.
“The covid-19 pandemic is not a solution for climate change.
However, it gives us an opportunity to adopt more sustained and ambitious climate measures, ”Taalas summarized.
New record in 2019
Data collected by WMO from the global network of measuring stations confirm that 2019 once again set a record in the concentration of carbon dioxide in the atmosphere, whose annual average was 410.5 parts per million (ppm), which It is almost 48% more than at pre-industrial levels, when that concentration was at 278 ppm.
But by studying some fossils and blocks of ice, estimates of concentrations from much longer ago can be made.
As Taalas recalled, to find a concentration similar to the current one on Earth, one must go back between three and five million years.
"The temperature was then two to three degrees Celsius warmer and the sea level between 10 and 20 meters higher than today," he added.
Carbon dioxide is the gas that contributes the most to global warming, but there are others that are also worrisome, such as methane.
And in 2019, the concentration of this gas - which retains more heat but barely remains in the atmosphere for a decade - again set a record high.
It reached 1,877 parts per billion (ppb), which is 160% more than pre-industrial levels (722 ppb).
The WMO explains that about 40% of methane emissions come from natural sources (such as wetlands).
The remaining 60% is due to activities related to human beings such as livestock, agriculture, fossil fuels or waste management.
Finally, the WMO highlights that the concentration of nitrous oxide, another greenhouse gas that also degrades the ozone layer, reached 332.0 ppb in 2019, which is 23% more than in the 18th century (270 ppmm).
To find out the most important news on Climate and Environment from EL PAÍS, sign up here for our
weekly
newsletter
.
Follow the Climate and Environment section on
and