( ( This ( diffused light ) ) ( ( is ( ( ( reflected back ) ( ( ( ( to ( the ( uniform ( cloud base ) ) ) ) and ) then ) ( to ( the surface ) ) ) ) again ) ) . ) )
(ROOT (S (NP (DT This) (JJ diffused) (NN light)) (VP (VBZ is) (VP (VBN reflected) (PRT (RP back)) (PP (PP (TO to) (NP (DT the) (JJ uniform) (NN cloud) (NN base))) (CC and) (RB then) (PP (TO to) (NP (DT the) (NN surface)))) (ADVP (RB again)))) (. .)))
This diffused light  is reflected back to the uniform cloud base and then to the surface again.
(ROOT (S (SBAR (WHADVP (WRB When)) (S (NP (NN light)) (VP (VBZ reflects) (PP (IN from) (NP (DT a) (JJ rough) (NN surface)))))) (, ,) (NP (PRP it)) (VP (VBZ gets) (ADJP (JJ diffused))) (. .)))