Notice is a type of Announcement. Notice is related to Detect. Detect is a synonym of Glimpse. Glimpse is a synonym of Ghost. 
Air is related to Necessary. Necessary is related to Have. Have is a synonym of Appear. Appear is a different concept from Vanish. 
Announcement <--IsA-- Notice <--RelatedTo--> Detect <--Synonym--> Glimpse <--Synonym--> Ghost 
Air <--RelatedTo--> Necessary <--RelatedTo--> Have <--Synonym--> Appear <--DistinctFrom--> Vanish 