( ( ( Characterized ( by ( ( a decrease ) ( in temperature ) ) ) ) ( with ( increasing altitude ) ) ) . )
(ROOT (S (VP (VBN Characterized) (PP (IN by) (NP (NP (DT a) (NN decrease)) (PP (IN in) (NP (NN temperature))))) (PP (IN with) (NP (VBG increasing) (NN altitude)))) (. .)))
Characterized by a decrease in temperature with increasing altitude.
(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)))) (. .)))