What makes SOSE unique is that the initial conditions, the northern boundary condition, and the atmospheric state are solved for via the adjoint method (also known as 4D-Var). An atmospheric boundary layer scheme is used to determine fluxes of heat, freshwater (salt), and momentum via bulk formulae (Large and Yeager 2008). It has a sea ice model, and uses the KPP mixed layer parameterization. The model is configured at 1/6 ° resolution and 42 depth levels of varying thickness. Here we inform use of the state estimate. SOSE is a dynamically mapped product, and like other mapped products has weaknesses due primarily to model error and lack of constraints. This contribution to the Climate Data Guide is in keeping with the latter goal. The goal of the the SOSE effort it to provide a basis for analyzing the underlying physics controlling the circulation and to provide a quantitatively useful climate baseline. It is based on the setup described in Mazloff et al. The mean circulation is shown in Figure 1. The following was contributed by Matthew Mazloff, September, 2016:Ī 2005-2010 Southern Ocean state estimate (SOSE) has been produced and made available ( ). For climate model evaluation, SOSE provides advantages over other climatologies such as the World Ocean Atlas by providing a self-consistent state estimate that satisfies momentum, volume, heat and freshwater conservation. In light of these issues, numerous validations of SOSE have been conducted, and the major biases in SOSE are well documented, as described in the Expert Guidance section of this webpage. Misfits to observations can also arise due to errors in the assimilation procedure and model biases.
Caveats about the use of SOSE are broadly similar to issues with reanalyses, in that the SOSE is most reliable in regions and for variables with good observational coverage, and more uncertain in regions and for variables with fewer observational constraints. Observations used include Argo float profiles, shipboard CTD measurements, various mooring data, satellite measurements of sea surface height and sea ice, among others. SOSE is a gridded dataset at 1/6 ° horizontal resolution, available at timesteps from daily to annually. Technically, SOSE is a solution to the MITgcm.
As such, it provides a quantitatively useful climatology of the mean-state of the Southern Ocean. The Southern Ocean State Estimate (SOSE) is a model-generated best fit to Southern Ocean observations.