Climate change acts as the primary driver of global and regional variations in sea surface properties, such as sea level rise (SLR), sea surface salinity (SSS), sea surface temperature (SST), and wind speed (WS). The Bay of Bengal (BoB) stands out due to its geographical location, complex climate patterns, diverse coastal and marine environment, and oceanographic processes. This study provides a new perspective on changes in multiple sea surface characteristics of the BoB through a comprehensive analysis of the high-resolution, long-term (1958–2022) Ocean Reanalysis System 5 (ORAS5) dataset using a modified Mann-Kendall (MMK) approach, capable of identifying unidirectional changes in sea surface characteristics by eliminating the influence of natural variability. The mean and maximum annual trends of SLR exhibit a range from 1.2 to 2.4 mm/year and 0.6 to 2.4 mm/year, respectively, with consistent SLR trends of 1.8 to 3.0 mm/year during both winter and monsoon seasons, indicating steady changes over the study period. Additionally, the study reveals decreasing maximum annual and seasonal trends of SSS in the northeast (-0.01 to -0.03 PSU/year) and increasing trends in the southern coastal area of Bangladesh (0.02 to 0.04 PSU/year). Most of the BoB shows mean annual and seasonal increases in SST ranging from 0.005 to 0.012 °C/year, with maximum increases of 0.012 to 0.026 °C/year adjacent to the Bay of Bengal. The mean annual WS trend ranges from 0.0001 to 0.0003 m/s/year, with no significant change in many areas but notable decreases of -0.009 to -0.003 m/s/year in the southeast part of the BoB during pre-monsoon and monsoon seasons. These findings contribute to a deeper understanding of the dynamics of the BoB under the influence of global climate change. Not applicable.
Alamgir et al. (Fri,) studied this question.