hibernal vs snowy

hibernal

adj
  • Of or pertaining to winter; brumal or hiemal 

snowy

adj
  • Covered with snow, snow-covered, besnowed. 

  • Snow-white in color, white as snow. 

  • Marked by snow, characterized by snow. 

noun
  • Synonym of snowy owl 

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