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Scientists discovered what
think is the cleanest
on Earth. Researchers from Colorado and Australia conducted research on the
of the air above Antarctica's Southern Ocean. They found a
between the south of Australia and Antarctica "unaffected" by
activity. Scientists say the area formed the
in the lower clouds. The
of the air showed that it was free from "anthropogenic
". These are pollutants or particles from human activity, or
from other continents. The scientists called this pollution-free area, "truly
".
