( ( For ( many years ) ) ( ( many ( atmospheric scientists ) ) ( ( have ( predicted ( that ( ( ( ( ( the ( human-induced increase ) ) ( in ( carbon dioxide ) ) ) and ) ( other ( ( radiatively active ) ( trace gases ) ) ) ) ( would ( ( ( enhance ( the ( greenhouse effect ) ) ) and ) ( cause ( ( a ( global warming ) ) ( of ( ( the ( earth 's ) ) surface ) ) ) ) ) ) ) ) ) ) . ) ) )
(ROOT (S (PP (IN For) (NP (JJ many) (NNS years))) (NP (JJ many) (JJ atmospheric) (NNS scientists)) (VP (VBP have) (VP (VBN predicted) (SBAR (IN that) (S (NP (NP (NP (DT the) (JJ human-induced) (NN increase)) (PP (IN in) (NP (NN carbon) (NN dioxide)))) (CC and) (NP (JJ other) (ADJP (RB radiatively) (JJ active)) (JJ trace) (NNS gases))) (VP (MD would) (VP (VP (VB enhance) (NP (DT the) (NN greenhouse) (NN effect))) (CC and) (VP (VB cause) (NP (NP (DT a) (JJ global) (NN warming)) (PP (IN of) (NP (NP (DT the) (NN earth) (POS 's)) (NN surface))))))))))) (. .)))
For many years many atmospheric scientists have predicted that the human-induced increase in carbon dioxide and other radiatively active trace gases would enhance the greenhouse effect and cause a global warming of the earth's surface.
(ROOT (S (NP (NNP Human) (NNS actions)) (VP (VBZ has) (VP (VBN increased) (NP (DT the) (NN greenhouse) (NN effect)))) (. .)))