Originally Posted by
flyallnite
Because it was determined that the word 'Turbulence' causes a fear reaction in many people. Rough air sounds less threatening.
But don't we want the passengers to have some concern so that they stay in their seats with their belt fastened?
And over time, rough air will begin to have the same connotation as turbulence and a new term will need to be created. It reminds me of PC culture. If one term becomes offensive, a new term will have to be used that will eventually become offensive also.