Intercomparisons of high‐resolution global ocean analyses: Evaluation of a new synthesis in tropical oceans

A new high‐resolution global analysis product is constructed from a fully coupled surface wave‐tide‐circulation Ocean Model developed by the First Institute of Oceanography Coupled Ocean Model (FIO‐COM). The performance of the FIO‐COM analysis data set is assessed based on comparisons with two other widely used high‐resolution global analysis products (Copernicus marine and environment monitoring service and HYbrid isopycnal‐sigma‐pressure coordinate ocean model), and observations in tropical oceans. Through comparison with observations, the FIO‐COM analysis is shown to be able to accurately capture the large‐scale mixed layer depth (MLD) structures in the tropical oceans during all seasons. Seasonal variations of MLDs can exceed ±80% in the southern and northern tropical oceans (10°‐25°S and 10°‐25°N) in both boreal winter and summer, as inferred from observations and FIO‐COM analysis data. Quantitative assessments of the 20°C isothermal depth, temperature at 5°m depth, and temperature and salinity profiles, among the analyses and in situ observations are also conducted. The capability of the FIO‐COM analysis to reflect the observed sea surface temperature variability during the 2015 El Niño episode is further investigated through comparisons with observations from 19 TAO buoys located in the Niño 3.4 region. All indicate the high quality of the new data set.