https://ogma.newcastle.edu.au/vital/access/ /manager/Index ${session.getAttribute("locale")} 5 https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:32930 Tue 11 Oct 2022 08:56:03 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:18293 Sat 24 Mar 2018 08:04:26 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:42243  0.85) at the outer reef flat and small γs values (γs < 0.1) at the inner reef flat. This indicates that there is an increase in wave energy dissipation in shallow water, most likely due to increased breaker and bed frictional dissipation. The measured wave energy dissipation across the entire reef flat could, on average, be modelled accurately; however, this required location specific calibration of the free parameters, the wave friction factor (fw) and γ, and further suggests that there is no value for either parameter that is universally applicable to coral reef flats. Despite model calibration inaccuracies were still observed, primarily at the outer reef flat. These inaccuracies reflected the observed cross-reef variation of γ on the reef flat and potentially the limitations of random wave breaker dissipation models in complex surf zones. Our results have implications for the use of wave energy dissipation models in predicting breaker dissipation and subsequent benthic community change on coral reef flats, and suggest that careful consideration of the free parameters in such models (such as fw and γ) is required.]]> Fri 19 Aug 2022 11:56:44 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:34017 b) is a fundamental variable in parametric wave height transformation models. It plays a key role in quantifying how much energy dissipation occurs due to wave breaking. Several authors have used different parameterisations to account for Q_b; however, to the authors' knowledge, very few studies have experimentally obtained a value for the fraction of broken waves across the surf zone using field data. This paper addresses this issue by describing a methodology to quantify Q_b using a combination measured pressure transducer data and remotely sensed data collected at the northern end of Seven Mile Beach, Gerroa, NSW. Pixel intensity timeseries were extracted from a timestack at the exact locations where the pressure transducers were deployed. These timeseries are compared to individual waves identified in the pressure record and the waves are classified as broken if a strong pixel peak matches a wave crest. When compared to visually identified waves, the broken wave classification algorithm was found to be correct 94.25% of the time. Results indicate that Q_b is inversely proportional to water depth but highly variable at similar mean water depths. The variability in Q_b showed a degree of correlation with the variation in the ratio between short (seaswell) and long (infragravity) wave energy in the inner surf zone. Probability density functions for all waves and broken waves are calculated and results indicate that wave heights in the surf zone (broken and unbroken) are not Rayleigh distributed. In fact, wave height distributions were statistically different to the Rayleigh distribution for all cases analysed, whereas they are fully described by a normal distribution in 87.65% of the cases for broken waves and in 80.25% of the cases for all waves.]]> Fri 01 Feb 2019 10:37:09 AEDT ]]>