Quantifying Anomalous Coastal Processes with Fractional Calculus-Based Models

[Extract] The emerging mathematical methods developed from fractional calculus are worth immediate attention in marine and coastal sciences. The term “anomalous diffusion” refers to the mechanisms described by a fractional differential equation (FDE) or fractional partial differential equation (FPDE) compared to the processes described by the classic diffusion equation which is regarded as the “normal” diffusion [10, 16]. The recent advances in many fields have demonstrated that the anomalous process is universal, which implies that coastal processes are also anomalous.