Barotropic Tides and Tidal Datums in Florida Coastal Waters

The present study simulates barotropic tides and currents in the Florida (FL) coastal waters and the Straits of Florida (SFL) using a high-resolution, two-dimensional version of the Advanced Circulation model (ADCIRC -2DDI). The model domain spans from eastern Gulf of Mexico (GOM) across the SFL to the entire Southern Atlantic Bight (SAB). The finite-element model grid consists of 353,718 nodes and 622,367 triangular elements, with a resolution ranging from 16 m to 41 km. A finely resolved spatial model resolution is an important factor to ensure realistic reproductions of tidal and current fields. The fields of tidal harmonics, current ellipses, tidal datums, energy fluxes, and the bottom friction dissipation rates are derived from the modeled water level and current time series. The results indicate favorable model-data agreement. In addition to reproducing tidal and current fields, this study focuses on examining the tidal dynamics and energetics over the SFL and its adjacent waters. This study reveals an amphidromic point of the principle solar constituent (K₁) centered around the Bimini Island. It is located offshore the southeast Florid Shelf; its formation is attributed to superposition of tides propagating in opposite directions. This study identifies that energy in the SFL originates from the SAB. The energy flux is attributed predominantly to the principle lunar semidiurnal constituent (M₂). It propagates into the Straits through three pathways: along the east FL shelf (EFS); a deep channel between islands in the northern Bahamas; and the northeast coast of Cuba. Across the Straits the energy flux progresses from east to west. Once into the eastern GOM, it turns rapidly to a northward direction, then finally turning eastward onto the west FL shelf (WFS). The shallow, nearshore regions display the strongest energy dissipation rate of the entire domain. The areas of less than 10 m water depth dissipates about 5 GW energy, accounting for over 75 percent of the total tidal energy loss over the entire model domain. Of the rest 25 percent energy loss, waters between 10–50 m depths make 24 percent and even deeper waters cause the remaining 1 percent.