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

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

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