( ( Climate ( for ( ( the purpose ) ( of ( this classification ) ) ) ) ) ( ( refers ( to ( ( a ( long ( term ( average condition ) ) ) ) ( of ( ( the weather ) ( in ( a ( given area ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NP (NN Climate)) (PP (IN for) (NP (NP (DT the) (NN purpose)) (PP (IN of) (NP (DT this) (NN classification)))))) (VP (VBZ refers) (PP (TO to) (NP (NP (DT a) (JJ long) (NN term) (NN average) (NN condition)) (PP (IN of) (NP (NP (DT the) (NN weather)) (PP (IN in) (NP (DT a) (VBN given) (NN area)))))))) (. .)))
Climate for the purpose of this  classification refers to a long term average condition of the weather in a given area.
(ROOT (S (NP (NN Climate)) (VP (VBZ is) (NP (NP (DT the) (JJ long-term) (NN average)) (PP (IN of) (NP (NP (NN weather)) (PP (IN in) (NP (DT a) (JJ particular) (NN spot))))))) (. .)))