Development of small vessel advisory and forecast services system for safe navigation and operations at sea by N.D. Aditya, K.G. Sandhya, R. Harikumar and T.M. Balakrishnan

First, the discussers wish to compliment the authors, Aditya et al. (2022) (hereafter referred to as A22), on their results involving the development of a small vessel advisory and forecast services system for safe navigation and operation at sea for the Indian Ocean regime. These comments and discussion focus on the steepness index parameter (Is) used within the Small Vessel Advisory Services (SVAS) system (see Figure 3 in A22) and point out that regional wave statistics can be used to determine and review the properties of Is in relation to significant wave height, allowing a robust method for determining and quantifying warning thresholds. A22 used the steepness index as one of the three indices in the boat safety index (see Equation (6) in A22). The steepness index is given as