cloud cover vs elements

cloud cover

noun
  • The percentage or fraction of the sky obscured by clouds. 

elements

noun
  • The weather, such as wind or rain. 

  • The basic tenets of an area of knowledge, basics, fundamentals. 

  • The bread and wine of the Eucharist. 

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