( ( Explain ( why ( ( the temperature ) ( increases ( as ( the altitude ) ) ) ) ) ) ( ( increases ( in ( the stratosphere ) ) ) . ) )
(ROOT (S (NP (NP (NNP Explain)) (SBAR (WHADVP (WRB why)) (S (NP (DT the) (NN temperature)) (VP (VBZ increases) (PP (IN as) (NP (DT the) (NN altitude))))))) (VP (VBZ increases) (PP (IN in) (NP (DT the) (NN stratosphere)))) (. .)))
Explain why the temperature increases as the altitude increases in the stratosphere.
(ROOT (S (PP (IN As) (NP (NN altitude) (NNS rises))) (, ,) (NP (DT the) (NN temperature)) (VP (VBZ increases) (PP (IN in) (NP (DT the) (NN thermosphere)))) (. .)))