An assessment of the Indian Ocean mean state and seasonal cycle in a suite of interannual CORE-II simulations
We present an analysis of annual and seasonal mean characteristics of the Indian Ocean circulation and water masses from 16 global ocean-sea-ice model simulations that follow the Coordinated Ocean-ice Reference Experiments (CORE) interannual protocol (CORE-II). All simulations show a similar large-s...
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ftncar:oai:drupal-site.org:articles_23040 2023-09-05T13:23:05+02:00 An assessment of the Indian Ocean mean state and seasonal cycle in a suite of interannual CORE-II simulations Rahaman, H. (author) Srinivasu, U. (author) Panickal, S. (author) Durgadoo, J.V. (author) Griffies, S.M. (author) Ravichandran, M. (author) Bozec, A. (author) Cherchi, A. (author) Voldoire, A. (author) Sidorenko, D . (author) Chassignet, E.P. (author) Danabasoglu, Gokhan (author) Tsujino, H. (author) Getzlaff, K. (author) Ilicak, M. (author) Bentsen, M. (author) Long, Mathew (author) Fogli, P.G. (author) Farneti, R. (author) Danilov, S. (author) Marsland, S.J. (author) Valcke, S. (author) Yeager, Stephen (author) Wang, Q. (author) 2020-01-01 https://doi.org/10.1016/j.ocemod.2019.101503 en eng Ocean Modelling--Ocean Modelling--14635003 articles:23040 ark:/85065/d7222xzx doi:10.1016/j.ocemod.2019.101503 Copyright 2019 Author(s). This work is licensed under a Creative Commons Attribution 4.0 International license. article Text 2020 ftncar https://doi.org/10.1016/j.ocemod.2019.101503 2023-08-14T18:50:41Z We present an analysis of annual and seasonal mean characteristics of the Indian Ocean circulation and water masses from 16 global ocean-sea-ice model simulations that follow the Coordinated Ocean-ice Reference Experiments (CORE) interannual protocol (CORE-II). All simulations show a similar large-scale tropical current system, but with differences in the Equatorial Undercurrent. Most CORE-II models simulate the structure of the Cross Equatorial Cell (CEC) in the Indian Ocean. We uncover a previously unidentified secondary pathway of northward cross-equatorial transport along 75 degrees E, thus complementing the pathway near the Somali Coast. This secondary pathway is most prominent in the models which represent topography realistically, thus suggesting a need for realistic bathymetry in climate models. When probing the water mass structure in the upper ocean, we find that the salinity profiles are closer to observations in geopotential (level) models than in isopycnal models. More generally, we find that biases are model dependent, thus suggesting a grouping into model lineage, formulation of the surface boundary, vertical coordinate and surface salinity restoring. Refinement in model horizontal resolution (one degree versus 1/4 degree) does not significantly improve simulations, though there are some marginal improvements in the salinity and barrier layer results. The results in turn suggest that a focus on improving physical parameterizations (e.g. boundary layer processes) may offer more near-term advances in Indian Ocean simulations than refined grid resolution. 1852977 Article in Journal/Newspaper Sea ice OpenSky (NCAR/UCAR - National Center for Atmospheric Research/University Corporation for Atmospheric Research) Indian Ocean Modelling 145 101503 |
institution |
Open Polar |
collection |
OpenSky (NCAR/UCAR - National Center for Atmospheric Research/University Corporation for Atmospheric Research) |
op_collection_id |
ftncar |
language |
English |
description |
We present an analysis of annual and seasonal mean characteristics of the Indian Ocean circulation and water masses from 16 global ocean-sea-ice model simulations that follow the Coordinated Ocean-ice Reference Experiments (CORE) interannual protocol (CORE-II). All simulations show a similar large-scale tropical current system, but with differences in the Equatorial Undercurrent. Most CORE-II models simulate the structure of the Cross Equatorial Cell (CEC) in the Indian Ocean. We uncover a previously unidentified secondary pathway of northward cross-equatorial transport along 75 degrees E, thus complementing the pathway near the Somali Coast. This secondary pathway is most prominent in the models which represent topography realistically, thus suggesting a need for realistic bathymetry in climate models. When probing the water mass structure in the upper ocean, we find that the salinity profiles are closer to observations in geopotential (level) models than in isopycnal models. More generally, we find that biases are model dependent, thus suggesting a grouping into model lineage, formulation of the surface boundary, vertical coordinate and surface salinity restoring. Refinement in model horizontal resolution (one degree versus 1/4 degree) does not significantly improve simulations, though there are some marginal improvements in the salinity and barrier layer results. The results in turn suggest that a focus on improving physical parameterizations (e.g. boundary layer processes) may offer more near-term advances in Indian Ocean simulations than refined grid resolution. 1852977 |
author2 |
Rahaman, H. (author) Srinivasu, U. (author) Panickal, S. (author) Durgadoo, J.V. (author) Griffies, S.M. (author) Ravichandran, M. (author) Bozec, A. (author) Cherchi, A. (author) Voldoire, A. (author) Sidorenko, D . (author) Chassignet, E.P. (author) Danabasoglu, Gokhan (author) Tsujino, H. (author) Getzlaff, K. (author) Ilicak, M. (author) Bentsen, M. (author) Long, Mathew (author) Fogli, P.G. (author) Farneti, R. (author) Danilov, S. (author) Marsland, S.J. (author) Valcke, S. (author) Yeager, Stephen (author) Wang, Q. (author) |
format |
Article in Journal/Newspaper |
title |
An assessment of the Indian Ocean mean state and seasonal cycle in a suite of interannual CORE-II simulations |
spellingShingle |
An assessment of the Indian Ocean mean state and seasonal cycle in a suite of interannual CORE-II simulations |
title_short |
An assessment of the Indian Ocean mean state and seasonal cycle in a suite of interannual CORE-II simulations |
title_full |
An assessment of the Indian Ocean mean state and seasonal cycle in a suite of interannual CORE-II simulations |
title_fullStr |
An assessment of the Indian Ocean mean state and seasonal cycle in a suite of interannual CORE-II simulations |
title_full_unstemmed |
An assessment of the Indian Ocean mean state and seasonal cycle in a suite of interannual CORE-II simulations |
title_sort |
assessment of the indian ocean mean state and seasonal cycle in a suite of interannual core-ii simulations |
publishDate |
2020 |
url |
https://doi.org/10.1016/j.ocemod.2019.101503 |
geographic |
Indian |
geographic_facet |
Indian |
genre |
Sea ice |
genre_facet |
Sea ice |
op_relation |
Ocean Modelling--Ocean Modelling--14635003 articles:23040 ark:/85065/d7222xzx doi:10.1016/j.ocemod.2019.101503 |
op_rights |
Copyright 2019 Author(s). This work is licensed under a Creative Commons Attribution 4.0 International license. |
op_doi |
https://doi.org/10.1016/j.ocemod.2019.101503 |
container_title |
Ocean Modelling |
container_volume |
145 |
container_start_page |
101503 |
_version_ |
1776203671235723264 |