"The specification of a physical process by the phrase due_to_process means that the quantity named is a single term in a sum of terms which together compose the general quantity named by omitting the phrase. \"Eastward\" indicates a vector component which is positive when directed eastward (negative westward). Atmosphere_Xward_stress is a stress which tends to accelerate the atmosphere in direction X." . . "Climate and Forecast (CF)" . "atmosphere eastward stress due to gravity wave drag" . . . .