( This ( ( has ( ( biological consequences ) ( because ( ( ( the burning ) ( of ( these ( fossil fuels ) ) ) ) ( ( ( releases ( the CO2 ) ) back ) ( into ( ( the atmosphere ) ( where ( ( ( too much ) ( of it ) ) ( can ( cause ( global warming ) ) ) ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (DT This)) (VP (VBZ has) (NP (NP (JJ biological) (NNS consequences)) (SBAR (IN because) (S (NP (NP (DT the) (NN burning)) (PP (IN of) (NP (DT these) (JJ fossil) (NNS fuels)))) (VP (VBZ releases) (NP (DT the) (NN CO2)) (PRT (RP back)) (PP (IN into) (NP (NP (DT the) (NN atmosphere)) (SBAR (WHADVP (WRB where)) (S (NP (NP (RB too) (RB much)) (PP (IN of) (NP (PRP it)))) (VP (MD can) (VP (VB cause) (NP (JJ global) (NN warming))))))))))))) (. .)))
This has biological consequences because the burning of these fossil fuels releases the CO2 back into the atmosphere where too much of it can cause global warming.
(ROOT (S (NP (JJ Co2) (NN gas)) (VP (VBZ is) (VP (VBN released) (PP (IN into) (NP (NP (DT the) (NN atmosphere)) (SBAR (WHADVP (WRB when)) (S (NP (JJ fossil) (NNS fuels)) (VP (VBP are) (VP (VBN burned))))))))) (. .)))