“…The ORA (Ocean Reanalysis) Intercomparison Project was initiated under CLIVAR GSOP and GODAE‐Oceanview and has produced a series of papers examining global ocean reanalyses and focusing on different aspects of the ocean state (e.g., steric sea level, air‐sea fluxes, ocean heat, and salt content among others). These were then brought together in a special issue of Climate Dynamics (Balmaseda et al, ; Chevallier et al, ; Karspeck et al, ; Palmer et al, ; Shi et al, ; Storto et al, ; Masina et al, ; Toyoda, Fujii, Kuragano, Kamachi, et al, ; Toyoda, Fujii, Kuragano, Kosugi, et al, ; Tietsche et al, ; Valdivieso et al, ). A further paper on the polar oceans was later added (Uotila et al, ).…”