Objective array design for three-dimensional temperature and salinity observation: Application to the South China Sea

• Published in: Acta oceanologica Sinica Vol. 41; no. 7; pp. 65 - 77
• Main Authors: Qu, Mengxue, Wei, Zexun, Wang, Yanfeng, Wang, Yonggang, Xu, Tengfei
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.07.2022; Springer Nature B.V; Shandong Key Laboratory of Marine Science and Numerical Modeling,Qingdao 266061,China%First Institute of Oceanography,and Key Laboratory of Marine Science and Numerical Modeling,Ministry of Natural Resources,Qingdao 266061,China; First Institute of Oceanography,and Key Laboratory of Marine Science and Numerical Modeling,Ministry of Natural Resources,Qingdao 266061,China; Laboratory for Regional Oceanography and Numerical Modeling,Pilot National Laboratory for Marine Science and Technology(Qingdao),Qingdao 266237,China
• Subjects: Algorithms; Arrays; Climatology; Clustering; Consolidation; Design; Earth and Environmental Science; Earth Sciences; Ecology; Engineering Fluid Dynamics; Environmental Chemistry; Marine & Freshwater Sciences; Mathematical analysis; Mesoscale processes; Mooring; Oceanography; Optimization; Orthogonal functions; Salinity; Salinity effects; Temperature; Temperature variations; The South China Sea Annual Meeting 2020; South China Sea; South China Sea; center clustering; observation system simulation experiment; optimal array design; empirical orthogonal function; K-center clustering
• ISSN: 0253-505X; 1869-1099
• DOI: 10.1007/s13131-021-1975-z

In this study, a moored array optimization tool (MAOT) was developed and applied to the South China Sea (SCS) with a focus on three-dimensional temperature and salinity observations. Application of the MAOT involves two steps: (1) deriving a set of optimal arrays that are independent of each other for different variables at different depths based on an empirical orthogonal function method, and (2) consolidating these arrays using a K -center clustering algorithm. Compared with the assumed initial array consisting of 17 mooring sites located on a 3°×3° horizontal grid, the consolidated array improved the observing ability for three-dimensional temperature and salinity in the SCS with optimization efficiencies of 19.03% and 21.38%, respectively. Experiments with an increased number of moored sites showed that the most cost-effective option is a total of 20 moorings, improving the observing ability with optimization efficiencies up to 26.54% for temperature and 27.25% for salinity. The design of an objective array relies on the ocean phenomenon of interest and its spatial and temporal scales. In this study, we focus on basin-scale variations in temperature and salinity in the SCS, and thus our consolidated array may not well resolve mesoscale processes. The MAOT can be extended to include other variables and multi-scale variability and can be applied to other regions.