( ( ( The region ) ( above ( 90 km ) ) ) ( ( is ( ( the ( Earth 's ) ) ( thermosphere ( where ( ( ( the absorption ) ( of ( ( extreme ( ultraviolet radiation ) ) ( from ( the Sun ) ) ) ) ) ( ( results ( in ( ( a ( ( very rapid ) increase ) ) ( in temperature ) ) ) ) ( with altitude ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NP (DT The) (NN region)) (PP (IN above) (NP (CD 90) (NN km)))) (VP (VBZ is) (NP (NP (DT the) (NN Earth) (POS 's)) (NN thermosphere) (SBAR (WHADVP (WRB where)) (S (NP (NP (DT the) (NN absorption)) (PP (IN of) (NP (NP (JJ extreme) (JJ ultraviolet) (NN radiation)) (PP (IN from) (NP (DT the) (NNP Sun)))))) (VP (VBZ results) (PP (IN in) (NP (NP (DT a) (ADJP (RB very) (JJ rapid)) (NN increase)) (PP (IN in) (NP (NN temperature))))) (PP (IN with) (NP (NN altitude)))))))) (. .)))
The region above 90 km is the Earth's thermosphere where the absorption of extreme ultraviolet radiation from the Sun results in a very rapid increase in temperature with 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)))) (. .)))