The correct representation of the 18.61‐year nodal tide is essential for an interpretation of the evolution of mean sea level, as errors cause misleading bias. The nodal tide is currently estimated by applying correction factors in harmonic analysis, which are derived from the equilibrium tide. From the equilibrium tide, correction values f for amplitude and u for phase are determined, which alter lunar tidal constituents, depending on the nodal cycle. This approach has proven to be valid for many tide gauges, even though the impact of the nodal tide in shelf seas has been shown to differ from their theoretical correction value. Hence, tidal constituents from tide records in the North Atlantic shelf region were analyzed for their nodal amplitude and phase lag with a new multiple, nonlinear regression approach, which is able to approximate the nodal modulation quantitatively and its agreement to the theoretical equilibrium tide. Results show an overestimation of the lunar M₂ and N₂ constituents by the equilibrium of more than 2.7% in the Wadden Sea, while O₁ and K₂ are underestimated by 1–4.6%, which would produce an error of 2–5 cm for example, in the German Wadden Sea. Additionally, a process‐based model of the North Sea was applied at the diurnal minimum and maximum of the nodal cycle to calculate a spatial distribution of f and u. Results confirm the spatially varying nodal satellite modulation in friction dominated, shallow water regions.

中文翻译：

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评估北海潮汐调制的组合建模与测量方法

由于误差会引起误解，因此正确解释18.61年的潮汐对解释平均海平面的变化至关重要。当前，通过在谐波分析中应用校正因子来估算节点潮汐，这些校正因子是从平衡潮汐推导出来的。从平衡潮中，振幅和u的校正值f确定相位，根据节点周期改变月潮成分。尽管已经证明了潮汐在架子海中的影响与其理论校正值不同，但该方法已被证明对许多潮位计都是有效的。因此，使用一种新的多元非线性回归方法，分析了北大西洋大陆架区域潮汐记录中的潮汐成分的波幅和相位滞后，该方法能够定量地逼近潮汐调制及其与理论平衡潮汐的一致性。结果表明，瓦登海中的月球M ₂和N ₂成分被平衡超过2.7％，而O ₁和K则高估了月球M ₂和N _2的成分。₂被低估了1-4.6％，例如，在德国瓦登海，这将产生2-5 cm的误差。此外，在节点周期的昼夜最小值和最大值处应用了基于北海的基于过程的模型，以计算f和u的空间分布。结果证实了在摩擦为主的浅水区域中空间卫星节点调制的空间变化。