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, The resulting algorithm has a slightly enlarged stability range and is less dissipative at the price of a slightly higher phase error

, 16), right, green) is, as expected

, 281105, ? given by (B.4) and ? given by (B.2) is formally first order in time with (as required) second order damping (|?| = 1 ? ?µ 2 + O(µ 4 )) with a range of stability and a phase error closed to the original ROMS scheme