base camp vs camping

base camp

noun
  • An encampment used temporarily for storing supplies and preparing for a larger activity, such as mountain climbing or hunting. 

camping

noun
  • The recreational activity of temporarily living in a tent or similar accommodation, usually in the wilderness. 

  • The act of setting up a camp. 

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