However, there are many processes that affect recruitment variability of cod, and to isolate and study a single process is imposssible as processes act in a non-linear fashion. The figure shows the large interannual varibility of the numbers of recruits at age 3 years from 1946 to 2005.
	The max and minimums values occur only 4 years between, and are correlated to the sea water temperature and inflow of atlantic water  onto the Norwegian  shelf and Barents Sea.