Barcelona (EFE).- Researchers from the Barcelona Institute of Marine Sciences (ICM-CSIC) have observed that plankton in the polar oceans emit benzene and toluene, two gases of biological origin that contribute to the formation of clouds and affect the weather.
The work, published in the journal Science Advances, describes the first measurements of benzene and toluene in the polar oceans and indicates that these compounds have a biological origin, contrary to what was thought until now, that their presence in polar marine air it was proof of the extent of human contamination from the burning of coal and oil or the use of solvents, among others.
The study, in which the Rocasolano Institute of Physical Chemistry (IQFR-CSIC) and the Plymouth Marine Laboratory (PML) have collaborated, recalls the importance of clouds, which filter solar radiation, to understand past and future climate changes. future.
“If we don’t get the clouds right, we won’t get the weather right,” said the ICM-CSIC researcher and lead author of the study, Charel Wohl, who acknowledged that “the multiple ingredients that make up the seeds are just beginning to be revealed.” From the clouds”.
Analyze the relationship between plankton and clouds in areas with clean air
The only way to know how the atmospheric composition was regulated before the profound changes generated by human activity in the industrial era is to study those regions where the air is still clean, such as the polar zones.
To carry out this study, the scientists measured the concentrations of benzene and toluene in surface water and in the air during two oceanographic campaigns: one in the Arctic and another in the Southern Ocean.
The distribution of these gases, their relationship to the amount of phytoplankton (vegetable plankton) and the fact that the ocean constantly emitted them into the atmosphere instead of capturing them from it, led the researchers to the conclusion that they had a biological origin. .
Then, incorporating the data into a global model of atmospheric chemistry and climate, they found that benzene and toluene emitted from the ocean contributed significantly to aerosol production.
This was especially the case in the extremely clean and uncontaminated atmosphere of the Southern Ocean: where these two gases increased the amount of organic aerosols by 8% and up to 80% in transient situations.
A global phenomenon that would now be masked by the impact of pollution
According to the paper’s authors, the natural effect of marine benzene and toluene on atmospheric chemistry was most likely a widespread and global phenomenon before the Industrial Revolution, but now it would be masked by the widespread impact of pollution.
According to IQFR-CSIC researcher Alfonso Saiz-López, “climate models will have to consider benzene and toluene emissions from the oceans if they want to hit the clouds in both past and future climate projections.”
For his part, the ICM-CSIC researcher and co-author of the study Rafel Simó has concluded that “this is another example of how millions of years of evolution have shaped the interactions between the ocean and the atmosphere, in such a way that oceanic life does not it has not only adapted to the climate, but has contributed to regulating it”.
In the future, the team will delve into the study of the impact of microscopic life in the ocean on the atmosphere and to do so, next February they will travel again to Antarctic waters to confirm the finding and make more measurements.
