( ( ( Clouds and ) precipitation ) ( ( are ( caused ( by ( ( ( rising air ) , ) ( while ( ( clear weather ) ( is ( caused ( by ( ( sinking air ) ( -LRB- ( 5-8 -RRB- ) ) ) ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NNS Clouds) (CC and) (NNS precipitation)) (VP (VBP are) (VP (VBN caused) (PP (IN by) (NP (NP (VBG rising) (NN air)) (, ,) (SBAR (IN while) (S (NP (JJ clear) (NN weather)) (VP (VBZ is) (VP (VBN caused) (PP (IN by) (NP (NP (VBG sinking) (NN air)) (PRN (-LRB- -LRB-) (NP (CD 5-8)) (-RRB- -RRB-)))))))))))) (. .)))
Clouds and precipitation are caused by rising air, while clear weather is caused by sinking air (5-8).
(ROOT (NP (NP (NP (VBG Rising)) (CC and) (NP (VBG sinking) (NN air) (NNS influences))) (VP (VBN precipitation) (PP (IN in) (NP (DT a) (NN region)))) (. .)))