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Abstract Beachface steepness is widely thought to modulate storm cut, long-term shoreline trend, and post-event recovery, but multi-decadal, transect-scale evidence is scarce. In this study, it was quantified how beachface slope relates to (i) event-scale shoreline retreat, (ii) recovery time, and (iii) net multi-decadal shoreline movement. Two sites (IDs aus0032 and aus0033) comprising 390 cross-shore transects and 194,867 shoreline positions from 1987 to 05–22 to 2025-05-06. Mean slopes: 0.053 (aus0032) and 0.051 (aus0033); slope ranges: 0.045–0.080 and 0.030–0.185. Long-term linear trends span 0.13 → 0.94 m yr −1 (all 87 transects accreting) at aus0032 and − 22.86 → +5.91 m yr −1 at aus0033 (210 accreting, 91 eroding, 2 near-zero). Time series were resampled monthly and quality-controlled. Erosive events were flagged when month-to-month shoreline change ≤ −5 m. Recovery time was the months required to return to within 1 m of the pre-event level (pre-event window = 3 months; search window = 24 months). Associations between slope and (a) retreat magnitude and (b) recovery time were tested using Spearman rank correlation and OLS with robust (HC1) errors; slope–trend associations were also evaluated. Steeper beachfaces experienced smaller typical monthly retreats. Spearman ρ for slope vs median negative monthly change was 0.25 ( p = 0.0206) at aus0032, 0.39 ( p = 2.7 × 10 −12 ) at aus0033, and 0.32 overall ( p = 8.3 × 10 −11 ). OLS effect sizes indicate that a 0.01 increase in slope reduced (made less negative) the median retreat by ~0.31 m (aus0032) and ~ 0.21 m (aus0033). Severe retreats (5th percentile) also weakened with slope: ~0.64 m and ~ 0.23 m per 0.01 slope at aus0032 and aus0033, respectively (both p 1.5 years. Management should treat slope as a short-term resilience indicator, while decadal shoreline change and recovery pace likely depend more on alongshore sediment supply, nearshore morphology, and forcing histories. • Found that beachface slope can be used for short-term risk, not long-term coastal planning. • Steeper beaches retreat less during storms. • Recovery time scales with event size, not slope; half recover in about 6 months. • Long-term shoreline change is largely independent of beachface slope. • Recovery from erosion is driven by event severity, not beach morphology.
Ahmet Durap (Sat,) studied this question.