Bias correction of sea surface temperature retrospective forecasts in the South China Sea
Bias correction of sea surface temperature retrospective forecasts in the South China Sea作者机构:School of Marine Science and TechnologyTianjin UniversityTianjin 300072China Tianjin Key Laboratory for Oceanic MeteorologyTianjin 300074China
出 版 物:《Acta Oceanologica Sinica》 (海洋学报(英文版))
年 卷 期:2022年第41卷第2期
页 面:41-50页
核心收录:
基 金:The National Key Research and Development Program of China under contract No.2018YFC1406206 the National Natural Science Foundation of China under contract No.41876014
主 题:sea surface temperature retrospective forecasts bias correction backpropagation neural network empirical orthogonal function analysis South China Sea
摘 要:Offline bias correction of numerical marine forecast products is an effective post-processing means to improve forecast accuracy. Two offline bias correction methods for sea surface temperature(SST) forecasts have been developed in this study: a backpropagation neural network(BPNN) algorithm, and a hybrid algorithm of empirical orthogonal function(EOF) analysis and BPNN(named EOF-BPNN). The performances of these two methods are validated using bias correction experiments implemented in the South China Sea(SCS), in which the target dataset is a six-year(2003–2008) daily mean time series of SST retrospective forecasts for one-day in advance, obtained from a regional ocean forecast and analysis system called the China Ocean Reanalysis(CORA),and the reference time series is the gridded satellite-based SST. The bias-correction results show that the two methods have similar good skills;however, the EOF-BPNN method is more than five times faster than the BPNN method. Before applying the bias correction, the basin-wide climatological error of the daily mean CORA SST retrospective forecasts in the SCS is up to-3°C;now, it is minimized substantially, falling within the error range(±0.5°C) of the satellite SST data.