CMCC Global Ocean Reanalysis System (C-GLORS)

The following was contributed by Dr. Andrea Storto (CMCC, Italy), October, 2014:

"Summary: The CMCC Global Ocean Physical Reanalysis System (C-GLORS) is used at CMCC to simulate the state of the ocean in the last decades. It consists of a variational data assimilation system (OceanVar), capable of assimilating all in-situ observations along with altimetry data, and a forecast step performed by the ocean model NEMO coupled with the LIM2 sea-ice model.

Key Strengths:

-Data dissemination is provided for a very large number of ocean parameters

-An extensive validation has been conducted and is freely available, confirming the good quality of the dataset

-The reanalysis is performed at high resolution (1/4 degree) and spans the last 30 years, covering the entire era of meteorological satellites

Key Limitations:

-Quality may be discontinuos and depend on observation coverage

-Uncertainty estimates are simply derived through verification skill scores

-Net surface heat flux seems underestimated at high latitudes

C-GLORS provides a 3D picture of the state of the ocean at 1/4 degree resolution for the meteorological satellite era (1982-2012).

It can be used for a wide range of applications, from climate monitoring to ocean dynamics studies, to models validation and comparisons, and downstream application (e.g. fisheries, biogeochemistry, etc.).

While climate signals are generally well reproduced, users should pay attention to the period where changes in observing system are present (mostly when altimetric missions start, October 1992, or when Argo data come in the system, 2001-2004)."##