Scientists have analyzed air trapped in ice cores and found that the atmospheric concentration of nitrous oxide was about 0.20 ppm around the year 1900.
(Scientists; have analyzed; air trapped in ice cores) (air; trapped; in ice cores) (Scientists; found; that the atmospheric concentration of nitrous oxide was about 0.20 ppm around the year) Context(Scientists found,List([0, 59))):(the atmospheric concentration of nitrous oxide; was; about 0.20 ppm around the year)
Scientists found,List([0, 59))
Scientists air Scientists the atmospheric concentration of nitrous oxide
have analyzed trapped found was
air trapped in ice cores
in ice cores
that the atmospheric concentration of nitrous oxide was about 0.20 ppm around the year
about 0.20 ppm around the year