NASA EXPLAINS DUST BOWL DROUGHT. NASA scientists have an explanation for one of the worst climatic events in the history of the United States, the Dust Bowl drought, which devastated the Great Plains and all but dried up an already depressed American economy in the 1930's.
The short run [in economics] is a period of time in which the quantity of at least one input is fixed and the quantities of the other inputs can be varied. The long run is a period of time in which the quantities of all inputs can be varied.
In later macroeconomic usage, the long run is the period in which the price level for the overall economy is completely flexible as to shifts in aggregate demand and aggregate supply. In addition there is full mobility of labor and capital between sectors of the economy and full capital mobility between nations.