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Scientists have discovered what they believe to be the cleanest air Earth. Researchers Colorado State University and the Australian Bureau Meteorology conducted research the purity the air above Antarctica. They found a region the Southern Ocean, between the south Australia and Antarctica, that was "unaffected" human activity. The scientists said the area they researched formed the atmosphere the lower clouds. The analysis the air showed that it was totally free from "anthropogenic aerosols". These are pollutants or particles derived human activity, or dust from other continents. The scientists called this pollution-free area, "truly pristine".

The scientists analysed the structure airborne microbes in the lower clouds the Southern Ocean. They looked at the DNA the microbes and tracked where they came . Their analysis included monitoring wind trajectories to detect how far the microbes may have travelled. They found that the atmospheric eco-system was very much "isolated," self-contained, and free contaminants from elsewhere the world. The source the microbes was the Southern Ocean, rather than airborne pollutants other continents. The researchers concluded that the Southern Ocean is one very few places Earth that has been "minimally affected anthropogenic activities.

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