Formulation of a new explicit tidal scheme in revised LICOM2.0

Tides play an important role in ocean energy transfer and mixing, and provide major energy for maintaining thermohaline circulation. This study proposes a new explicit tidal scheme and assesses its performance in a global ocean model. Instead of using empirical specifications of tidal amplitudes and...

Full description

Bibliographic Details
Published in:Geoscientific Model Development
Main Authors: Jin, Jiangbo, Guo, Run, Zhang, Minghua, Zhou, Guangqing, Zeng, Qingcun
Format: Article in Journal/Newspaper
Language:English
Published: Copernicus Publications 2022
Subjects:
Online Access:https://doi.org/10.5194/gmd-15-4259-2022
https://noa.gwlb.de/receive/cop_mods_00061232
https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00060721/gmd-15-4259-2022.pdf
https://gmd.copernicus.org/articles/15/4259/2022/gmd-15-4259-2022.pdf
Description
Summary:Tides play an important role in ocean energy transfer and mixing, and provide major energy for maintaining thermohaline circulation. This study proposes a new explicit tidal scheme and assesses its performance in a global ocean model. Instead of using empirical specifications of tidal amplitudes and frequencies, the new scheme directly uses the positions of the moon and sun in a global ocean model to incorporate tides. Compared with the traditional method that has specified tidal constituents, the new scheme can better simulate the diurnal and spatial characteristics of the tidal potential of spring and neap tides as well as the spatial patterns and magnitudes of major tidal constituents (K1 and M2). It significantly reduces the total errors of eight tidal constituents (with the exception of N2 and Q1) in the traditional explicit tidal scheme, in which the total errors of K1 and M2 are reduced by 21.85 % and 32.13 %, respectively. Relative to the control simulation without tides, both the new and traditional tidal schemes can lead to better dynamic sea level (DSL) simulation in the North Atlantic, reducing significant negative biases in this region. The new tidal scheme also shows smaller positive bias than the traditional scheme in the Southern Ocean. The new scheme is suited to calculate regional distributions of sea level height in addition to tidal mixing.