The spatial and temporal variability of the high individual wave heights, which pose a hazard in India’s shelf seas, has not been investigated. In this study, the spatial and temporal variation of hourly maximum individual wave height (H_max) in the Indian shelf seas is examined based on 40 years ERA5 Re-Analysis data from European Centre for Medium-Range Weather Forecasts. Waverider buoy data from five locations are used to assess ERA5 H_max. The variability of H_max in different temporal scales; daily, monthly and interannual and their linkages with major ocean-atmosphere coupled interaction in the Pacific and the Indian Ocean are presented. Wave climatology throughout India’s western shelf seas shows average H_max exceeding 2 m during most of the year. Maximum H_max in the western shelf seas is during May–July, whereas in the southern tip and the eastern shelf seas are during the tropical cyclones and are either in October–December or May. Maximum H_max is 17.94 m, and it occurred at the northern Bay of Bengal on 25 May 2009 during the passage of tropical cyclone Aila. Spatial variations in H_max between locations spaced at 1.5° latitude are less than 10% in the northwestern and southeastern shelf seas, but large variations (~ 28%) are in the southwestern and northeastern shelf seas. Annual mean H_max shows contrasting trends when data for 1979 to 2018 and 1992 to 2018 is considered. Indian Ocean Dipole influence on the H_max suggests negative correlations in the western shelf seas and positive correlations in the eastern shelf seas. The correlation with climate indices is similar for both significant wave height and H_max.

中文翻译：

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印度陆架海面的每小时最大个人波高-最近40年的时空变化

尚未研究高单个波浪高度的时空变化，这在印度的架子海中构成危险。在这项研究中，基于欧洲中距离天气预报中心的40年ERA5再分析数据，研究了印度陆架海面中每小时最大个体波高（H _max）的时空变化。来自五个位置的Waverider浮标数据用于评估ERA5 H _max。H _max在不同时间尺度上的变异性；介绍了每日，每月和每年一次，以及它们与太平洋和印度洋主要海洋-大气耦合相互作用的联系。印度西部大陆架海域的波浪气候显示平均H _max一年中的大部分时间超过2 m。西部陆架海的最大H _max在5月至7月期间，而在南端和东部陆架海的最大H _max在热带气旋期间，并且在10月至12月或5月。最大H _max为17.94 m，发生在2009年5月25日热带气旋Aila穿越孟加拉湾北部时。在西北和东南架子海中，以1.5°纬度隔开的位置之间的H _max的空间变化小于10％，但在西南和东北架子海中，Hmax的空间变化小于（〜28％）。当考虑1979年至2018年以及1992年至2018年的数据时，年平均_Hmax呈现出截然相反的趋势。印度洋偶极子对H _max的影响表明在西部架子海中负相关，而在东部架子海中正相关。对于重要的波高和H _max，与气候指数的相关性相似。