Plankton holds the key for the formation of brighter clouds over the Southern Ocean, with the tiny organisms producing gases and organic matter that underpin cloud droplet formation.
Many questions have boggled the scientific community as to how the skies could have looked before the industrial era and the widespread pollution stemming from burning fossil fuel made their way into the advancing of civilization.
An interesting research looking at perhaps one of the most pristine skies still existing tried to answer some of the questions related to cloud formation. The study stems from the research teams of the Pacific Northwest National Laboratory and the University of Washington.
Published in the Science Advances journal on July 17th, the study took a closer look at the Southern Ocean plankton and its role in bright cloud formation.
Robert Wood of the University of Washington and atmospheric sciences professor, underlined the idea driving the study:
“We have really poor observations of everything in the Southern Ocean, and it’s a really important region. It also provides a glimpse of how a pristine, pre-industrial area might behave”.
Thus, focusing on plankton, the joint research team found that it is responsible for producing organic matter and airborne gases that materialize into bright clouds which increase sunlight reflection.
During the summer, the clouds hanging over the Southern Ocean reflect a higher amount of sunlight than they would typically do, were the plankton not present to influence the process. Brimming with life in the form of these tiny organisms that form the plankton, the Southern Ocean sees a cloud droplet concentration twice as high.
Ocean life greatly influences cloud formation. Over a one year timeframe, the cloud droplets that form thanks to the plankton lead to the formation of bright clouds that average a reflection of 4 watts/square meter in solar energy.
Thus, the Southern Ocean plankton holds the key for cloud droplet formation. How does it do that? According to the research team, there are two mechanisms that lead to cloud droplets formation and to the bright clouds later one.
First, plankton emits dimethyl sulfide. This gas gives the particular smell of sulfur to sea water. Also, it leads to particle release that eventually form the cloud droplets.
Secondly, the plankton itself becomes material for cloud droplet formation. As organic matter brimms at the surface of the Southern Ocean, the wind picks it up and stirs it through the air, adding to the organic component of bright cloud formation.
The two mechanisms through which plankton influences bright cloud formation over the Southern Ocean lead to the doubling of cloud droplet atmospheric concentration during the summer period.
The Southern Ocean is an ideal region to study cloud formation. As the cloud droplets develop on aerosol particles, pristine environments such as this are the ideal spots such studies.
Photo Credits seahack.org