GODAE is sponsored by
3.3 Ocean State Estimation for Climate Research
Lead author: Tony Lee (JPL/NASA)
Author/co-authors: Tony Lee1, Toshiyuki Awaji2, Magdalena Balmaseda3, Eric Greiner4, Detlef Stammer5
1JPL, NASA, USA
2 Kyoto University, Japan
3 ECMWF, UK
4 MERCATOR, Toulouse, France
5 ZMAW, Germany
Abstract
Spurred by the development of satellite and in-situ observing systems, Ocean state estimation geared towards climate research has flourished in the past decade as part of GODAE's effort. A decade ago, no product was available to describe the time-evolving, three-dimensional state of the global ocean. Today, a suite of such products have been generated and being applied to studies of a wide range of subjects such as physical oceanography and climate, biogeochemical cycles, and geodesy. This presentation will review recent achievements of ocean state estimation and highlight the applications of these products to investigate sea level variability and changes, upper-ocean heat and salt contents, meridional overturning circulation and heat transport. The suitability of the ocean synthesis products to provide information about climate variability is evaluated. In particular, the sensitivity of the detected climate signals to the ocean observing system is addressed with the help of observing system experiments. Examples of such applications will be presented. Many assimilation groups from different countries have participated in a CLIVAR/GODAE global ocean reanalysis evaluation effort in which intercomparison was performed for a suite of diagnostic quantities and indices (among estimation products as well as with observations when available). Some of intercomparison will be discussed to highlight the consistency and fidelity of the estimation products, to define the requirement of observational accuracy necessary to better constrain/distinguish these products, and to identify the potential areas of improvement needed for the estimation systems. The presentation will also describe future technical and resources challenges.
(Last Updated: 13-10-2008)