Assimilation of ARGO data into ECMWF models: operational impacts and diagnostics of ocean transports

Gregory C. Smith, .Keith Haines, Arthur Vidard, David Anderson, Magdalena Balmaseda, Chunlei Liu, Alberto Troccoli

Environmental Systems Science Centre
University of Reading
3 Earley Gate, Reading, RG6 6AL, UK

ARGO data is now part of operational seasonal forecasting system 3 at ECMWF. The impact of improved coverage of ocean temperatures and the availability of coincident ocean salinity data are examined. In particular, the influence of salinity data is demonstrated through a new S(T) assimilation scheme. Assimilation diagnostics show that the ocean model forecasts of all quantities, including currents, have improved. The ocean model is then used to assess ocean transports and water mass variability. It is shown that salinity measurements have a big impact on these transport products, and it is argued that ARGO data is an excellent tool for monitoring the impact and the role of the ocean in climate variability.