Anthropogenic factors continue to warm the oceans by storing sufficient memory of past accumulated effects resulting in higher Sea surface temperature (SST) and Ocean heat content (OHC) invigorating tropical cyclogenesis and tropical cyclone intensity. Prior studies indicate that an increase in accumulated tropical cyclone heat potential, a measure of OHC is directly related to high intense storms of longer durations. The present study is an attempt to understand the role of OHC in tropical cyclogenesis for the Bay of Bengal (BoB). Unlike the other global ocean basins, the BoB is a semi-marginal sea in the North Indian Ocean (NIO) having differential water mass characteristics attributed due to tremendous influx from riverine discharges, seasonal reversing monsoonal wind system and complex ocean circulation features. This study provides a detailed assessment on SST and OHC distributions during the pre- and post-monsoon seasons covering a period of 21 years (1991–2016) over four identified sub-domains, the potential locations for tropical cyclogenesis. The daily ERA-Interim, ORAS4, ORAS5 and 3-h RAMA buoy datasets were used in the present study. The spatial distribution and variations of SST and OHC anomalies during pre- and post-monsoon seasons in the BoB were also examined. Differential nature of inter-annual SST variability was noticed in the study region. Highest variability in SST is evidenced during both pre- and post-monsoon seasons for the northern Bay region showing a warming bias of ∼ 1.7 °C in the past 2 decades. Contrasting variability is also noticed for the eastern Bay during pre-monsoon that is almost three times higher as compared to the post-monsoon season. Maximum OHC variability is found for the southern and central-eastern Bay regions. It is seen that OHC variability has a strong tele-connection with Oceanic Niño Index associated with El Niño/La Niña events in the Pacific basin with their amplitudes found to increase from northern to southern regions of the Bay.

通过储存对过去累积影响的足够记忆，人为因素继续使海洋变暖，从而导致更高的海表温度（SST）和海洋热量（OHC）激发热带气旋和热带气旋强度。先前的研究表明，热带气旋的累积热潜能的增加（一种OHC的量度）与持续时间较长的强风暴直接相关。本研究试图了解OHC在孟加拉湾（BoB）的热带气旋发生中的作用。与其他全球海洋盆地不同，BoB是北印度洋（NIO）的半边际海域，其水质特征各不相同，这归因于河流排放物，季节性季风逆风和大量海洋环流特征的大量涌入。这项研究对季风前后前后21年（1991-2016年）的SST和OHC分布进行了详细评估，涵盖四个已确定的子域，即热带气旋的潜在位置。本研究使用每日ERA-Interim，ORAS4，ORAS5和3-h RAMA浮标数据集。在BoB的季风前后，SST和OHC异常的空间分布和变化也得到了检查。在研究区域中注意到年际SST变异性的差异性。在北部湾地区的季风前后前后，SST的变化最大，在过去的20年中显示出约1.7°C的升温偏向。季风发生前东部海湾的变化也很明显，比季风后季节高出近三倍。发现南部和中东部海湾地区的最大OHC变异性。可以看出，OHC变异性与太平洋盆地ElNiño/ LaNiña事件相关的大洋Niño指数具有很强的遥相关性，并且发现其振幅从海湾的北部到南部增加。