It stated that levels of atmospheric carbon dioxide--a greenhouse gas--have increased significantly over the past several decades.
(It; stated; that levels of atmospheric carbon dioxide--a greenhouse gas--have increased significantly over the past several decades) Context(It stated,List([0, 9))):(levels of atmospheric carbon dioxide; have increased; significantly; T:over the past several decades)
It stated,List([0, 9))
It levels of atmospheric carbon dioxide
stated have increased
that levels of atmospheric carbon dioxide--a greenhouse gas--have increased significantly over the past several decades
significantly T:over the past several decades