摘要
High-accuracy Sea level prediction is important for understanding marine environments and climate change.In this work,a deep convolutional neural network(CNN)combined with attention mechanism(ADNN)is established for sea level anomaly(SLA)prediction from historical satellite observations.Multi-year(1998-2020)radar altimetry observed SLA pattern samples in the South China Sea are used for model training and testing.Compared with existing deep learning models such as CNN and convolutional long short-term memory(ConvLSTM)network,ADNN demonstrates the highest accuracies of 94.0%,91.1%,88.4%and 86.2%for 1-d,3-d,5-d and 7-d SLA field predictions,with regional average root mean square errors(RMSE)of 0.27 cm,0.51 cm,0.80 cm and 1.09 cm,respectively.The integration of CNN and attention mechanism significantly improves the model performance,especially in estimating short-term sea level changes,with a 74.7%reduction in the RMSE for 1-d predictions compared to the baseline CNN model.Comparative experiments also show that the ADNN model performs well when the input data contains a certain degree of noise.Moreover,a multivariate ADNN(M-ADNN)model is designed to investigate the impacts of environmental variables such as sea surface temperature(SST)and wind on SLA prediction.The model yields a slightly higher accuracy but the results are quite similar to those of the ADNN model.The findings suggest that,although SST or wind can affect sea level changes,the ADNN model demonstrates the ability to identify and learn sufficient information about sea level changes solely from satellite altimetry measurements of SLA,especially for relatively long-term(≥5 d)predictions.This eliminates the need for additional input parameter data,thereby improving the SLA prediction efficiency.
基金
The National Natural Science Foundation of China under contract Nos T2261149752 and 42476172
the Open Funding of the Technology Innovation Center for South China Sea Remote Sensing,Surveying and Mapping Collaborative Application,Ministry of Natural Resources,P.R.China under contract No.RSSMCA-2024-B001。
