A Numerical Study of Geomorphic and Oceanographic Controls on Wave-Driven Runup on Fringing Reefs with Shore-Normal Channels

Many populated, tropical coastlines fronted by fringing coral reefs are exposed to wave-driven marine flooding that is exacerbated sea-level rise. Most not alongshore uniform, but bisected shore-normal channels; however, little known about the influence of such channels on variations runup and adjacent coastline. We conducted a parametric study using numeric model XBeach demonstrates channel results in substantial waves, water levels, resulting runup. Depending geometry forcing, greater either coastline terminus or at locations near extent channel. The impact increases for higher incident lower wave steepness, wider channels, narrower reef, shorter spacing. Alongshore variation infragravity waves predominantly responsible large-scale outside channel, whereas setup, sea-swell very-low frequency mainly increase inside These provide insight into which coastal most vulnerable high events, only widely available data as reef offshore conditions.