( ( Of ( particular importance ) ) ( ( ( is ( how ( ( ( climate variations ) ( such ( as ( ( ( ( ( El ( Ni o ) ) , ) ( the ( North ( Atlantic Oscillation ) ) ) ) or ) ( long-term trends ) ) ) ) ) influence ) ) ) ( ( the probability ) ( of ( occurrence ( of ( extreme ( weather events ) ) ) ) ) ) ) . ) )
(ROOT (S (PP (IN Of) (NP (JJ particular) (NN importance))) (VP (VBZ is) (SBAR (WHADVP (WRB how)) (S (NP (NP (NN climate) (NNS variations)) (PP (JJ such) (IN as) (NP (NP (NNP El) (NNP Ni) (NNP o)) (, ,) (NP (DT the) (NNP North) (NNP Atlantic) (NNP Oscillation)) (CC or) (NP (JJ long-term) (NNS trends))))) (VP (VBP influence))))) (NP (NP (DT the) (NN probability)) (PP (IN of) (NP (NP (NN occurrence)) (PP (IN of) (NP (JJ extreme) (NN weather) (NNS events)))))) (. .)))
Of particular importance is how climate variations such as El Ni o, the North Atlantic Oscillation or long-term trends influence the probability of occurrence of extreme weather events.
(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))))))) (. .)))