A Multi-Spatial Scale Ocean Sound Speed Prediction Method Based on Deep Learning

• Published in: Journal of marine science and engineering 2024-11, Vol.12 (11), p.1943
• Main Authors: Liu, Yu, Ma, Benjun, Qin, Zhiliang, Wang, Cheng, Guo, Chao, Yang, Siyu, Zhao, Jixiang, Cai, Yimeng, Li, Mingzhe
• Format: Article
• Language: English
• Subjects: Accuracy; Acoustic properties; Acoustics; Algorithms; Analysis; Coupling; Deep learning; Dimensional analysis; Efficiency; Error analysis; Forecasting; Investigations; K-nearest neighbors algorithm; Long short-term memory; long short-term memory neural networks; Machine learning; Methods; Neural networks; Ocean; Ocean temperature; Predictions; Root-mean-square errors; Salinity; Salinity data; sound speed prediction; Sound velocity; Spatial analysis; Spatial data; Spatial discrimination learning; Spatial memory; spatiotemporal attention mechanisms; Spatiotemporal data; Statistical methods; Time series; Underwater acoustics
• ISSN: 2077-1312; 2077-1312
• DOI: 10.3390/jmse12111943

As sound speed is a fundamental parameter of ocean acoustic characteristics, its prediction is a central focus of underwater acoustics research. Traditional numerical and statistical forecasting methods often exhibit suboptimal performance under complex conditions, whereas deep learning approaches demonstrate promising results. However, these methodologies fall short in adequately addressing multi-spatial coupling effects and spatiotemporal weighting, particularly in scenarios characterized by limited data availability. To investigate the interactions across multiple spatial scales and to achieve accurate predictions, we propose the STA-ConvLSTM framework that integrates spatiotemporal attention mechanisms with convolutional long short-term memory neural networks (ConvLSTM). The core concept involves accounting for the coupling effects among various spatial scales while extracting temporal and spatial information from the data and assigning appropriate weights to different spatiotemporal entities. Furthermore, we introduce an interpolation method for ocean temperature and salinity data based on the KNN algorithm to enhance dataset resolution. Experimental results indicate that STA-ConvLSTM provides precise predictions of sound speed. Specifically, relative to the measured data, it achieved a root mean square error (RMSE) of approximately 0.57 m/s and a mean absolute error (MAE) of about 0.29 m/s. Additionally, when compared to single-dimensional spatial analysis, incorporating multi-spatial scale considerations yielded superior predictive performance.