( ( Changes ( in ( solar radiation ) ) ) ( ( ( ( are natural ) and ) ( occur ( with ( the ( 11-year ( Sunspot cycle ) ) ) ) ) ) . ) )
(ROOT (S (NP (NP (NNS Changes)) (PP (IN in) (NP (JJ solar) (NN radiation)))) (VP (VP (VBP are) (ADJP (JJ natural))) (CC and) (VP (VBP occur) (PP (IN with) (NP (DT the) (JJ 11-year) (NNP Sunspot) (NN cycle))))) (. .)))
Changes in solar radiation are natural and occur with the 11-year Sunspot cycle.
(ROOT (S (NP (NNS Sunspots)) (VP (VBP occur) (PP (IN in) (NP (DT a) (CD 11) (NN year) (NN cycle)))) (. .)))