Re-assessment and update of bulk longshore sediment transport formulas

Longshore sediment transport (LST) is one of the main drivers of beach morphology. Bulk LST formulas are routinely used in coastal management/engineering studies to assess LST rates and gradients. Over 50 years of research has resulted in several bulk LST formulas that have been tested with varying levels of rigor. In this study, the predictive skill of one of the most recent bulk LST formulas (Bayram et al., 2007) is evaluated. The calibration coefficients in the formula are improved using a least-squares optimization algorithm, resulting in a significant improvement in predictive skill. The generality of the improved formula is verified via the statistical methods of bootstrapping and cross-validation.