However, Professor Sonia Creditenois and her team suspected that the air over the Southern Ocean would be the least affected by humans and dust from the world’s continents.
The researchers found that the boundary layer air, which feeds the lower clouds over the southern ocean, is free of aerosol particles caused by human activity. – including burning fossil fuels, growing certain crops, producing fertilizers, and getting rid of sewage – or transporting it from other countries around the world.
The researchers decided to study what is in the air, and where it came from, using bacteria in the air as a diagnostic tool to infer the properties of the lower atmosphere.
“The aerosols that control the properties of SO clouds (the southern ocean) are closely related to the biological processes of the ocean, and that Antarctica appears to be insulated from the spread of microorganisms and the deposition of nutrients south from the southern continents,” explained research scientist and co-author of the study, Thomas Hill. .
He added, “In general, it indicates that the SO is one of the very few places on Earth that has been little affected by human activities.”
Scientists sampled air at the sea boundary level – part of the atmosphere that had direct contact with the ocean – while riding a research boat heading south to the edge of the ice at the South Pole from Tasmania, Australia. Then scientists examined the composition of airborne microbes, which are found in the atmosphere and often scattered by winds thousands of kilometers away.
Using DNA sequencing, trace the source, world of hind wind paths and first author Jun Uetake She found that the origins of the microbes were from the ocean.
From the bacterial composition of microbes, researchers concluded that aerosols from distant earth masses and human activities, such as pollution or soil emissions from land use change, do not travel south and into the air.
Scientists say the results show a stark difference to all other oceanographic studies in both the northern and subtropical hemisphere, which found that most microbes came from opposite continents.
Air pollution is already a global public health crisis, and it kills seven million people every year, according to the World Health Organization.
The health organization said that more than 80% of people living in urban areas who monitor air pollution are exposed to levels of air quality that exceed WHO guidelines, and low and middle income countries suffer from the highest exposure rates.