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Abstract
The present inability of coastal models is the incompetence prediction of changes in coastal sediment processes. As well as the beach response to longer term changes in sea level and wave climate, including beach recovery processes. A numerical model (NSBEACH) is developed based on some of the existing modules within SBEACH (Strom-induced BEAch CHange) model. The cross-shore transport only limitation in the model is acknowledged as a simplification to full 3-dimentional capability. An advantage is high efficiency in simulating the relative long-term coastal process in the developed model. The significant modification has been made to SBEACH to overcome the previous limitation in simulating beach recovery. The new model NSBEACH (New SBEACH) includes a new modification of parameters determining the onshore transport and beach accretion, an advanced numerical method for mid-term simulation (up to 1 year with hourly input data), and a variable swash zone boundary, as well as post-processing methodologies. The new NSBEACH model has been successfully compared with SUPERTANK experiment data, Bilinga Beach data at Gold Coast, Dewey Beach data from Delaware and Collaroy-Narrabeen Beach data from NSW. The modeled results are rigorously and objectively analysed with skill scores.The major coastal processes simulated are combined with multiple storm and accretion events within the surf zone and swash zone. Model performance evaluation method such as Root Mean Square Error, Residual Error, Brier Skill Scores and visual spatial displacement plot are applied to model result analysis to assess the accuracy of the new model. In conclusion, the NSBEACH model was successfully developed to simulate both beach erosion and accretion cycles within an economical running time. Moreover, NSBEACH is also capable of predicting the onshore recruitment of sand from a shoreface nourishment scheme. The NSBEACH model provides one of the few models which could effectively simulate beach erosion and recovery process.