flaring vs flickering

flaring

noun
  • The act of something that flares. 

  • The deliberate open-air burning of natural gas that is generated as a by-product of various petrochemical processes, especially oil extraction; gas flaring. 

flickering

noun
  • A short, uncertain burst. 

adj
  • shining unsteadily or varying rapidly in brightness (referring to a light or a source of light) 

How often have the words flaring and flickering occurred in a corpus of books? (source: Google Ngram Viewer )