earth science vs physiography

earth science

noun
  • Any of the sciences dealing with the planet Earth, such as geology and meteorology. 

physiography

noun
  • The subfield of geography that studies physical patterns and processes of the Earth. It aims to understand the forces that produce and change rocks, oceans, weather, and global flora and fauna patterns. 

  • The descriptive part of a natural science as distinguished from the explanatory or theoretical part. 

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