Procedure to derive wave period-dependent threshold NPP. (a) NPP distribution for (N = 600, Tsin = 45, Asin = 2, NCYC = 4); (b) PCf (green) and mean NPP (blue) for NCYC = 1 − 6 with (N = 600, Tsin = 45, Asin = 2); (c) Threshold NPP for Asin = 1 − 10 with (N = 600, Tsin = 45); (d) Asymptotic threshold NPP for Tsin = 25 − 100 with (N = 600). See text for details.!