Articles | Volume 18, issue 4
Technical note
19 Jul 2022
Technical note |  | 19 Jul 2022

Technical note: On seasonal variability of the M2 tide

Richard D. Ray

Data sets

Saint-Malo tide-gauge data SHOM

Short summary
Seasonal variability of the M2 ocean tide can be detected at many ports. The physical mechanisms underlying seasonality, in the broadest terms, are astronomical, frictional–advective interactions, and climate processes. Some of these induce annual modulations, some semiannual, in amplitude, phase, or both. This note reviews how this occurs and gives an example from each broad category. Phase conventions and their relationship with causal mechanisms, as well as nomenclature, are also addressed.