( ( As ( ( ( ( the ( coastal waters ) ) warm ) and ) ( ( day length ) ( increases ( ( ( towards and ) during ) ( spring ( and ( early summer ) ) ) ) ) ) ) ) ( , ( ( seawater quality ) ( ( becomes ( increasingly variable ) ) . ) ) ) )
(ROOT (S (SBAR (IN As) (S (S (NP (DT the) (JJ coastal) (NNS waters)) (ADJP (JJ warm))) (CC and) (S (NP (NN day) (NN length)) (VP (VBZ increases) (PP (IN towards) (CC and) (IN during) (NP (NN spring) (CC and) (JJ early) (NN summer))))))) (, ,) (NP (NN seawater) (NN quality)) (VP (VBZ becomes) (ADJP (RB increasingly) (JJ variable))) (. .)))
As the coastal waters warm and day length increases towards and during spring and early summer, seawater quality becomes increasingly variable.
(ROOT (S (NP (NP (DT A) (-LRB- -LRB-) (NN n) (-RRB- -RRB-) (NN increase)) (PP (IN in) (NP (NN length)))) (VP (VBZ happens) (PP (TO to) (NP (NN metal) (NN railroad) (NNS tracks))) (PP (IN during) (NP (NP (DT the) (NN heat)) (PP (IN of) (NP (DT a) (NN summer) (NN day)))))) (. .)))