intertidal zone vs seaside

intertidal zone

noun
  • The part of a shore between high water and low water, especially the beach exposed at maximum ebb spring tides. 

seaside

noun
  • The area by and around the sea; including the beach, promenade or cliffs 

adj
  • Related to a seaside. 

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