enforcement vs flash flood

enforcement

noun
  • The act of enforcing; compulsion. 

  • A giving force to; a putting in execution. 

  • That which enforces, constraints, gives force, authority, or effect to; constraint; force applied. 

flash flood

noun
  • A sudden, rapid flood, usually of short duration and local impact. 

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