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Scientists found what they think is the cleanest air on Earth. Researchers conducted research on the purity of the air above Antarctica. An area between the south of Australia and Antarctica was "unaffected" by human activity. The analysis of the air in the clouds showed it was free from "anthropogenic aerosols". These are pollutants from human activity, or dust from other continents. The scientists called this pollution-free area, "truly pristine".
The scientists analysed microbes in the clouds. They tracked where the DNA of the microbes came from. They monitored the wind to see how far the microbes travelled. They found the atmospheric eco-system was "isolated" and free from contaminants from elsewhere in the world. The microbes came from the Southern Ocean rather than other continents. The Southern Ocean is one of very few places on Earth "minimally affected" by pollution.
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