21 Mar 2023
 | 21 Mar 2023

Evaluation of the CMCC global eddying ocean model for the Ocean Model Intercomparison Project (OMIP2)

Doroteaciro Iovino, Pier Giuseppe Fogli, and Simona Masina

Abstract. This paper describes the global eddying ocean-sea ice simulation produced at the Euro-Mediterranean Center on Climate Change (CMCC) obtained following the experimental design of the Ocean Model Intercomparison Project phase 2 (OMIP2). The eddy-rich model is based on the NEMOv3.6 framework, with a global horizontal resolution of 1/16° and 98 vertical levels, and was originally designed for an operational short-term ocean forecasting system. Here, it is driven by one multi-decadal cycle of the prescribed JRA55-do atmospheric reanalysis and runoff dataset in order to perform a long-term benchmarking experiment.

To access the accuracy of simulated 3D ocean fields, and highlight the relative benefits of mesoscale activities, the GLOB16 performances are evaluated via a selection of key climate metrics against observational datasets and two other NEMO configurations at lower resolutions: an eddy-permitting resolution (ORCA025) and a non-eddying resolution (ORCA1) designed to form the ocean-sea ice component of the fully coupled CMCC climate model.

The well-known biases in the low-resolution simulations are significantly improved in the high-resolution model. The evolution and spatial pattern of large-scale features (such as sea surface temperature biases and winter mixed layer structure) in GLOB16 are generally better reproduced, and the large-scale circulation is remarkably improved compared to the low-resolution oceans. We find that eddying resolution is an advantage in resolving the structure of western boundary currents, the overturning cells, and flow through key passages. GLOB16 might be an appropriate tool for ocean climate modeling effort, even though the benefit of eddying resolution does not provide unambiguous advances for all ocean variables in all regions.

Doroteaciro Iovino et al.

Status: final response (author comments only)

Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor | : Report abuse
  • CC1: 'Comment on egusphere-2023-469', Alexander Shchepetkin, 23 Mar 2023
    • CC2: 'Reply on CC1', Doroteaciro Iovino, 05 Apr 2023
      • CC3: 'Reply on CC2', Alexander Shchepetkin, 05 Apr 2023
        • CC4: 'Reply on CC3', Doroteaciro Iovino, 15 May 2023
  • RC1: 'Comment on egusphere-2023-469', Anonymous Referee #1, 01 May 2023
  • RC2: 'Comment on egusphere-2023-469', Anonymous Referee #2, 19 May 2023

Doroteaciro Iovino et al.

Doroteaciro Iovino et al.


Total article views: 340 (including HTML, PDF, and XML)
HTML PDF XML Total BibTeX EndNote
250 78 12 340 3 1
  • HTML: 250
  • PDF: 78
  • XML: 12
  • Total: 340
  • BibTeX: 3
  • EndNote: 1
Views and downloads (calculated since 21 Mar 2023)
Cumulative views and downloads (calculated since 21 Mar 2023)

Viewed (geographical distribution)

Total article views: 351 (including HTML, PDF, and XML) Thereof 351 with geography defined and 0 with unknown origin.
Country # Views %
  • 1
Latest update: 04 Jun 2023
Short summary
The paper describes the model performance of three global ocean/sea ice configurations, from non-eddying (1°) to eddy-rich (1/16°) resolutions. Model simulations are obtained following the OMIP-2 protocol. We compare key global climate variables across the three models and against observations, emphasizing the relative advantages and disadvantages of running forced ocean–sea ice models at higher resolution.