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(CNN) – Scientists believe they have identified the cleanest air in the world, free of particles caused by human activity, located over the Southern Ocean, which surrounds Antarctica.
In a first-class study of the composition of bioaerosol in the Southern Ocean, researchers at Colorado State University identified an atmospheric region that remains unchanged by human activity.
Weather and climate are closely linked, connecting each part of the world with other regions. As the climate changes rapidly due to human activity, scientists and researchers struggle to find a corner of Earth that is unaffected by people.
However, Professor Sonia Kreidenweis 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 air in the boundary layer, which feeds the lowest clouds over the Southern Ocean, had no aerosol particles produced by human activity, including burning fossil fuels, planting certain crops, producing fertilizers. and the disposal of wastewater, or its transportation from other countries around the world.
Air pollution is caused by aerosols, which are solid and liquid particles and gases that are suspended in the air.
The researchers decided to study what was 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.
Study researcher and co-author Thomas Hill explained that “the aerosols that control the properties of the clouds of the Southern Ocean are strongly linked to ocean biological processes, and that Antarctica appears to be isolated from the dispersion of microorganisms to the south and deposition of nutrients from southern continents, “he said in a statement.
“Overall, it suggests that the Southern Ocean is one of the few places on Earth that has been minimally affected by anthropogenic activities,” he added.
Scientists took samples of the air at the marine limit level, the part of the atmosphere that has direct contact with the ocean, aboard a research ship that traveled south to the edge of the Antarctic ice from Tasmania, Australia. Scientists then examined the composition of microbes in the air, found in the atmosphere and often dispersed thousands of kilometers by the wind.
Using DNA sequencing, source tracking, and backtracking trajectories, scientist and lead author Jun Uetake discovered that the origins of the microbes were from the ocean.
From the bacterial composition of the microbes, the researchers concluded that aerosols from distant land masses and human activities, such as pollution or land emissions caused by the change in land use, did not travel south and into the air.
Scientists say the results show a big difference from all other ocean studies in both the northern and subtropical hemispheres, which found that most microbes came from upwind continents.
In the study, published Monday in the journal Proceedings of the National Academy of SciencesScientists described the area as “truly pristine.”
Air pollution is already a global public health crisis and kills seven million people each year, according to the World Health Organization (WHO).
Studies have shown that air pollution increases the risk of heart disease, stroke, and lung cancer.
More than 80% of people living in urban areas that monitor air pollution are exposed to air quality levels that exceed the limits of the WHO guidelines, the health organization said, and low-income countries and Mediums suffer the highest exposures.
However, as studies have shown, air pollution can cross geographic boundaries and affect people hundreds of miles from where it originated.
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