title: Ocean Data Assimilation in Support of Climate Applications: Status and Perspectives.
abstract: Ocean data assimilation brings together observations with known dynamics encapsulated in a circulation model to describe the time-varying ocean circulation. Its applications are manifold, ranging from marine and ecosystem forecasting to climate prediction and studies of the carbon cycle. Here, we address only climate applications, which range from improving our understanding of ocean circulation to estimating initial or boundary conditions and model parameters for ocean and climate forecasts. Because of differences in underlying methodologies, data assimilation products must be used judiciously and selected according to the specific purpose, as not all related inferences would be equally reliable. Further advances are expected from improved models and methods for estimating and representing error information in data assimilation systems. Ultimately, data assimilation into coupled climate system components is needed to support ocean and climate services. However, maintaining the infrastructure and expertise for sustained data assimilation remains challenging.
authors.affiliation: Centrum für Erdsystemforschung und Nachhaltigkeit (CEN), Universität Hamburg, 20148 Hamburg, Germany; email: detlef.stammer@uni-hamburg.de.
authors.forename: D
authors.initials: D
authors.lastname: Stammer
authors.affiliation: European Centre for Medium-Range Weather Forecasts, RG2 9AX Reading, United Kingdom.
authors.forename: M
authors.initials: M
authors.lastname: Balmaseda
authors.affiliation: Institute for Computational Engineering and Sciences and Jackson School of Geosciences, The University of Texas at Austin, Austin, Texas 78712.|Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139.
authors.forename: P
authors.initials: P
authors.lastname: Heimbach
authors.affiliation: Centrum für Erdsystemforschung und Nachhaltigkeit (CEN), Universität Hamburg, 20148 Hamburg, Germany; email: detlef.stammer@uni-hamburg.de.
authors.forename: A
authors.initials: A
authors.lastname: Köhl
authors.affiliation: Centre Européen de Recherche et de Formation Avancée en Calcul Scientifique (CERFACS), SUC URA, CNRS 1875, 31100 Toulouse, France.
authors.forename: A
authors.initials: A
authors.lastname: Weaver
mesh_terms: D057231:Climate Change; D017753:Ecosystem; D008962:Models, Theoretical; D009791:Oceanography / Q000639:trends*; D012623:Seawater / Q000737:chemistry*
keywords: climate predictions; data assimilation; data synthesis; modeling; observing system; ocean circulation