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<https://gcmd.earthdata.nasa.gov/kms/concept/ba7cc1c1-c5ef-43ff-9a2e-84629f0a94fa>
  ns0:altLabel [ ] ;
  skos:broader <https://gcmd.earthdata.nasa.gov/kms/concept/4eb1894b-35b4-406b-8864-944a42bc7702> ;
  skos:prefLabel "TOPAZ"@en ;
  skos:inScheme <https://gcmd.earthdata.nasa.gov/kms/concepts/concept_scheme/projects> ;
  skos:definition """Following the encouraging results of the DIADEM  MAST-III project, TOPAZ aims
at providing real-time forecasts for both the physics and ecology of the North
Atlantic ocean. 

As its predecessor, TOPAZ develops advanced data assimilation systems for a
coupled primitive equation ocean circulation and marine ecosystem model for the
North Atlantic and the Nordic Seas with enhanced resolution in the European
coastal zones, assimilating satellite data available for real time operational
use.

TOPAZ keeps improving the results obtained in DIADEM, partly thanks to the
increased computer resources recently available. Our strategy is to take
advantage of the newly available CPU and memory space for upgrading both the
circulation and the ecological models and for increasing their resolution.
Besides, the efficiency of the various data assimilation schemes is improved. 

Features of the new model system are the following :
-------------------------------------------
* The Miami Isopycnic Coordinate Ocean Model (MICOM) is replaced by the Hybrid
Coordinate Ocean Model (HYCOM). It adds a fixed vertical coordinate to the
original isopycnic coordinate and allows for a better description of the
vertical movements of water masses.
* The original ecological model by Fasham, Ducklow and Mc Kelvie (FDM model) is
improved so that the phytoplankton can adapt to changes in the physical and
biogeochemical environment. In particular, the new model allows variable carbon
to nitrogen (C:N) and carbon to chlorphyll ratios (C:N-REcoM= C:N Regulated
Ecosystem Model).
* An ice model is coupled to the physical model HYCOM, and measurements of ice
concentration and ice thickness are assimilated.
* The model grid resolution is increased (18 to 35 km), and a common
discretization for both the physics and biology is now possible, which
simplifies their coupling.

The data assimilation schemes used in the TOPAZ project are:
---------------------------------------------------
    * The Ensemble Kalman Filter (EnKF, used in the real-time experiment).
    * The Singular Evolutive Extended Kalman Filter (SEEK).
    * The Ensemble Optimal Interpolation (EnOI) scheme.

The observations used are satellite observed Sea Level Anomaly (SLA), Sea
Surface Temperature (SST), Sea-ice concentrations from SSMI and - soon -
Coriolis in-situ data.

The major outcomes in terms of products are short term forecasts issued weekly,
open for public access and end users.

TOPAZ data in the North Atlantic Ocean are freely available from the MERSEA LAS
server:  "http://www.mersea.eu.org"

TOPAZ Website:  "http://topaz.nersc.no/\""""@en ;
  a skos:Concept .

<https://gcmd.earthdata.nasa.gov/kms/concept/4eb1894b-35b4-406b-8864-944a42bc7702>
  skos:prefLabel "S - U"@en ;
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