Several scenarios were considered because of uncertainty of future levels of ozone pollution.
1	Several	several	ADJ	JJ	Degree=Pos	2	amod	2:amod	Discourse=context-background:8->6:2|Entity=(39-event-new-cf3-2-sgl
2	scenarios	scenario	NOUN	NNS	Number=Plur	4	nsubj:pass	4:nsubj:pass	Entity=39)
3	were	be	AUX	VBD	Mood=Ind|Number=Plur|Person=3|Tense=Past|VerbForm=Fin	4	aux:pass	4:aux:pass	_
4	considered	consider	VERB	VBN	Tense=Past|VerbForm=Part|Voice=Pass	0	root	0:root	_
5	because	because	ADP	IN	_	7	case	7:case	Discourse=causal-cause:9->8:0
6	of	of	ADP	IN	_	5	fixed	5:fixed	_
7	uncertainty	uncertainty	NOUN	NN	Number=Sing	4	obl	4:obl:because_of	Entity=(40-abstract-new-cf4-1-sgl
8	of	of	ADP	IN	_	10	case	10:case	_
9	future	future	ADJ	JJ	Degree=Pos	10	amod	10:amod	Entity=(41-abstract-new-cf5-2-coref
10	levels	level	NOUN	NNS	Number=Plur	7	nmod	7:nmod:of	_
11	of	of	ADP	IN	_	13	case	13:case	_
12	ozone	ozone	NOUN	NN	Number=Sing	13	compound	13:compound	Entity=(19-abstract-giv:inact-cf1-2-coref(5-substance-giv:inact-cf2-1-coref)
13	pollution	pollution	NOUN	NN	Number=Sing	10	nmod	10:nmod:of	Entity=19)41)40)|SpaceAfter=No
14	.	.	PUNCT	.	_	4	punct	4:punct	_
