Research Commons

Observations of alongshore variability of swash motions on an intermediate beach

Research Commons

Show simple item record Guedes, Rafael Marcondes Carvalho Bryan, Karin R. Coco, Giovanni 2012-11-07T23:05:36Z 2012-11-07T23:05:36Z 2012-10 2012
dc.identifier.citation Guedes, R.M.C. & Clarkson, B. D. (2012). Observations of alongshore variability of swash motions on an intermediate beach. Continental Shelf Research, 48(1), 61-74. en_NZ
dc.identifier.issn 0278-4343
dc.description.abstract Alongshore variability in swash motions - shoreline oscillations about the mean water level on the beach face - were investigated using video images and a high-resolution morphology survey on an intermediate beach. Under mild, swell-dominated offshore wave conditions, alongshore variation of up to 78$ in significant runup height . Rs (defined as 4 times the standard deviation of the swash time series) was observed. This variation was predominantly driven by energy at the incident (>0.05. Hz) frequencies (where most of the swash energy was observed), and, consistent with previous observations, was mainly controlled by changes in the slope of the beach face (measured at the mean swash location). However, alongshore patterning in wave breaking over the sandbar caused variation in the degree of wave dissipation along the beach and also resulted in alongshore changes to swash motions. Although alongshore changes in beach slope and wave breaking patterning over the bar were observed to be typically correlated, both were needed in a regression model to provide the best explaination of alongshore changes in . Rs. At infragravity frequencies (<0.05. Hz), alongshore variability was not well associated either with changes in beach slope or wave breaking patterning. Low-mode edge waves were observed in the swash measurements and their contribution to the total energy spectrum was greatest near the location where a shoal was observed, suggesting this shoal may play a role in forcing. The edge waves may have contributed to the swash variability observed at infragravity frequencies. However, in these reflective conditions, the infragravity band plays a secondary role in controlling alongshore variations to swash motions. en_NZ
dc.language.iso en
dc.publisher Elsevier Ltd en_NZ
dc.relation.ispartof Continental Shelf Research
dc.subject Alongshore variability en_NZ
dc.subject Beach slope en_NZ
dc.subject Edge waves en_NZ
dc.subject Sandbar en_NZ
dc.subject Swash en_NZ
dc.subject Wave breaking en_NZ
dc.title Observations of alongshore variability of swash motions on an intermediate beach en_NZ
dc.type Journal Article en_NZ
dc.identifier.doi 10.1016/j.csr.2012.08.022 en_NZ

Full-text options:

This item appears in the following Collection(s)

Show simple item record


Advanced Search



About Research Commons

My Account

Usage Statistics


  • Bookmark and Share