( ( Air-mass weather ) ( ( is ( ( ( ( ( ( ( the ( net effect ) ) ( of ( local ( surface circulation ) ) ) ) , ) terrain ) , ) and ) ( ( the ( modifying effect ) ) ( of ( significant ( water bodies ) ) ) ) ) ) . ) )
(ROOT (S (NP (JJ Air-mass) (NN weather)) (VP (VBZ is) (NP (NP (NP (DT the) (JJ net) (NN effect)) (PP (IN of) (NP (JJ local) (NN surface) (NN circulation)))) (, ,) (NP (NN terrain)) (, ,) (CC and) (NP (NP (DT the) (VBG modifying) (NN effect)) (PP (IN of) (NP (JJ significant) (NN water) (NNS bodies)))))) (. .)))
Air-mass weather is the net effect of local surface circulation, terrain, and the modifying effect of significant water bodies.
(ROOT (S (NP (NP (DT The) (NN movement)) (PP (IN of) (NP (NP (DT an) (NN air) (NN mass)) (PP (IN over) (NP (NP (NN earth) (POS 's)) (NN surface)))))) (VP (VBZ causes) (NP (JJ local) (NN weather) (NNS changes))) (. .)))