Semidiurnal inner shelf flow in the Southern California Bight

Semidiurnal variability of alongshore currents on the inner shelf of the Southern California Bight is investigated using a 7 year velocity and pressure time series. Analysis reveals that the M2-frequency alongshore current varies significantly over spatial scales of O(10km), inconsistent with the expected progressive surface tide. Instead, the observed variability is attributed to the influence of a northward-propagating, superinertial coastal trapped wave (CTW) that generates a quasi-barotropic (QBT) flow, defined as the portion of the depth-averaged alongshore current that is out of phase with the surface tide. A superinertial CTW model, forced by realistic bathymetry and stratification conditions, suggests that the dominant mode of variability is likely a mode-1 CTW with a wavelength of approximately 50km. The observations and model also reveal that seasonal changes in stratification modulate the wavelength and phase speed of the CTW, leading to a s..., , , # Data from: Semidiurnal inner shelf flow in the Southern California Bight

[https://doi.org/10.5061/dryad.x3ffbg7tk](https://doi.org/10.5061/dryad.x3ffbg7tk)

This dataset accompanies research investigating semidiurnal current variability on the inner shelf of the Southern California Bight. The observational data spans seven years (August 2011 to September 2018), collected at three monitoring sites along the 33m isobath off Southern California. The dataset integrates field measurements with numerical modeling results to examine coastal trapped wave dynamics and their influence on inner shelf circulation.

## Dataset Organization and Specifications

### Observational Data (SD\_IT\_Current\_Data.mat)

This MATLAB file contains the primary acoustic Doppler current profiler (ADCP) measurements, with variables stored in a structured array format. The data encompasses:

Velocity measurements (m/s):

* Depth-averaged alongshore and cross-shore components
* Filtered within the semidiurnal band...,