This study focuses on the impact of varying landfall timing in a tidal cycle (i.e., the spring-neap phase) and varying wind speeds (i.e., cyclone intensities) on the surge tides for the tropical cyclone Fani in the Bay of Bengal using a hydrodynamic finite element-based 2D (ADvanced CIRCulation) ADCIRC model setup. For atmospheric forcing, the Cyclostrophic Symmetric Holland wind Model (H80) and Generalized Asymmetric Holland Model (GAHM) model are used to estimate the wind fields from the IMD best track data. Comparisons with in-situ winds from moored buoys within the proximity of cyclone track showed that H80 simulated winds underestimate the observed winds in terms of magnitude followed by a mismatch in the wind directions as well. In contrast, the GAHM simulated wind fields, which are statistically better in terms of both magnitude and direction are used for different wind experiments. To understand the impact of the varying landfall timing and varying wind speeds on storm surges, a series of sensitivity experiments have been performed during a tidal cycle with modulated high and low winds along the cyclone track. The experiments considering varying landfall timing during a tidal cycle indicate the strongest surge tides (1.99 m) during the spring high tide phase, whereas the lowest surge tide of 0.94 m is observed during spring low tide. However, the surge tide at the actual time of landfall is 1.20 m which is during the transition from low tide to high tide. On the other hand, the combined impact of wind speeds and varying landfall timing indicated the strongest surge tides of 2.25 m during high wind conditions associated with spring high tides. In contrast, the surge tides decrease significantly during low tide and low wind conditions. This study confirms the importance of both winds and landfall timing on the storm surges, which will be crucial to forecast the storm surges associated with the tropical cyclones.

本研究的重点是潮汐周期中不同的登陆时间（即春季-小溪阶段）和不同的风速（即气旋强度）对孟加拉湾热带气旋 Fani 潮汐的影响，使用流体动力学基于有限元的 2D（高级 CIRCulation）ADCIRC 模型设置。对于大气强迫，使用回旋对称荷兰风模型 (H80) 和广义非对称荷兰模型 (GAHM) 模型从 IMD 最佳轨迹数据估计风场。与原位比较来自气旋轨道附近系泊浮标的风表明，H80 模拟风在强度方面低估了观测到的风，随后风向也不匹配。相比之下，GAHM 模拟的风场在大小和方向上都在统计上更好，用于不同的风实验。为了了解不同的登陆时间和不同的风速对风暴潮的影响，在潮汐周期中进行了一系列敏感性实验，其中沿气旋路径调整了强风和弱风。考虑到潮汐周期期间不同登陆时间的实验表明，春季高潮阶段的潮汐最强（1.99 m），而春季低潮阶段的最低潮汐为 0.94 m。然而，实际登陆时的涨潮为1.20 m，处于低潮到高潮的过渡期。另一方面，风速和不同登陆时间的综合影响表明，在与春季高潮相关的大风条件下，2.25 m 的最强潮汐。相比之下，潮汐在低潮和低风条件下显着减少。这项研究证实了风和登陆时间对风暴潮的重要性，这对于预测与热带气旋相关的风暴潮至关重要。相比之下，潮汐在低潮和低风条件下显着减少。这项研究证实了风和登陆时间对风暴潮的重要性，这对于预测与热带气旋相关的风暴潮至关重要。相比之下，潮汐在低潮和低风条件下显着减少。这项研究证实了风和登陆时间对风暴潮的重要性，这对于预测与热带气旋相关的风暴潮至关重要。