## 5 Conclusions  
This study evaluated the impacts of absorption coefficients on MBES backscatter data calibration in the East Sea of Korea, integrating historical CTD datasets from the KODC and in situ SVP measurements. By calculating absorption coefficients and incorporating site-specific water column parameters, the calibration process reduced discrepancies in backscatter intensity, with differences of up to 2.1 dB observed. These results demonstrate the feasibility of re-processing legacy MBES datasets to better align with measured oceanographic conditions. The findings suggest the importance of understanding spatiotemporal variations in absorption parameters for MBES calibration. The influences of other environmental factors, such as turbidity and suspended particles, in regions such as the South and West Seas could be considered in future research, which may provide additional insights for the improvement of calibration methodologies.  
**Supplementary Materials:** The following supporting information can be downloaded at [[https://www.mdpi.com/article/10.3390/app15031131/s1](https://www.mdpi.com/article/10.3390/app15031131/s1)]([https://www.mdpi.com/article/10.3390/app15031131/s1](https://www.mdpi.com/article/10.3390/app15031131/s1)), Figure S1: Seasonal average and standard deviation of water temperature; Figure S2: Seasonal average and standard deviation of salinity; Figure S3: Seasonal average and standard deviation of sound velocity; Figure S4: Overview of the developed GUI; Figure S5: The interpolation of KODC data; Figure S5: Comparison between interpolated KODC standard depth data and 1 m interval raw measured; Figure S6. Standard deviation of total absorption at the 15 selected points in the southern coastal region of the East Sea season represented in April; Figure S7. Standard deviation of total absorption at the 15 selected points in the southern coastal region of the East Sea season represented in October; Figure S8. Standard deviation of total absorption at the 15 selected points in the southern coastal region of the East Sea season represented in December.  
**Author Contributions:** Conceptualization, S.-U.I. and D.-G.P.; methodology, S.-U.I., C.K. and D.-G.P.; software, S.-U.I. and C.-A.L.; validation, S.-U.I., C.K. and D.-G.P.; formal analysis, S.-U.I.; investigation, S.-U.I.; resources, S.-U.I. and M.L.; data curation, S.-U.I.; writing--original draft preparation, S.-U.I.; writing--review and editing, S.-U.I., C.K. and D.-G.P.; visualization, S.-U.I.; supervision, D.-G.P.; project administration, C.K.; funding acquisition, D.-G.P. All authors have read and agreed to the published version of the manuscript.  
**Funding:** This research was supported by the Korea Institute of Marine Science & Technology Promotion (KIMST) funded by the Ministry of Oceans and Fisheries (RS-2022-KS221578, RS-2023-00256122).  
Data Availability Statement: Publicly available datasets were analyzed in this study. This data can be found in [[https://www.nifs.go.kr/kodc/soo_list.kodc](https://www.nifs.go.kr/kodc/soo_list.kodc)]([https://www.nifs.go.kr/kodc/soo_list.kodc](https://www.nifs.go.kr/kodc/soo_list.kodc)).  
The authors thank [PERSON] for their assistance in preparing the manuscript.  
Author [PERSON] was employed by the company MarineResearch Co. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.