A group of scientists believe they have found a piece of planet Earth where it can breathe the cleanest air in the world, free from any human activity, and have located it over the Southern Ocean, the large water mass that surrounds Antarctica.
In the first study of the Southern Ocean bioerosole composition, researchers from Colorado State University identified an atmospheric area untouched by human activity.
As the climate changes rapidly due to human activity, scientists and researchers find it difficult to find earthly nooks in which the human hand has had no impact.
However, Professor Sonia Kreidenweis and her team believed that the air over the Southern Ocean would be least affected by human activity and dust from other continents of the world.
The researchers found that the boundary layer air, which feeds lower clouds over the Southern Ocean, does not contain aerosol particles created by human activity, including burning fossil fuels, ejecting wastewater, producing fertilizer or planting certain crops, or being brought from other countries.
Air pollution is caused by aerosols, solids and liquid particles and gases floating in the air.
The scientists decided to study what was in the air and where it came from, using bacteria in the air as a diagnostic tool to reason the properties in the lower atmosphere.
Study scientist and co-author Thomas Hill explained that the aerosols that control cloud properties over the Southern Ocean are strongly linked to biological processes in the ocean and that Antarctica appears to be isolated from microorganisms and nutrient deposition from southern continents, he said in a statement. Overall, this suggests that the Southern Ocean is one of the few places on Earth that is minimally affected by anthropogenic activity, he added.
The scientists sampled the air at sea-level, a part of the atmosphere that has direct contact with the ocean, while in a research ship travelling south from Tasmania in Australia to antarctica ice.
The scientists then examined the composition of the microbes in the air found in the atmosphere and often spread by wind for thousands of kilometres.
With the help of DNA sequencing, by tracking sources and analysing winds, scientist and author Jun Uetake found that microbes come from the ocean.
From the bacterial composition of microbes, the researchers concluded that aerosols from remote areas on land and human activity, such as pollution, do not travel on it.
Scientists point out that the results show a big difference from all other ocean surveys, both in the northern hemisphere and in the subtropical region, which have found that most microbes come from continents.
In the study, published Monday in the journal Proceedings of the National Academy of Sciences, scientists described the area as “really pristine.”