Ngakala R. D., Alory G., Da-Allada C. Y., Kom O. E., Jouanno Julien, Rath W., Baloitcha E. (2023). Joint observation-model mixed-layer heat and salt budgets in the easterntropical Atlantic. Ocean Science, 19 (3), p. 535-558. ISSN 1812-0784.
Titre du document
Joint observation-model mixed-layer heat and salt budgets in the easterntropical Atlantic
Ngakala R. D., Alory G., Da-Allada C. Y., Kom O. E., Jouanno Julien, Rath W., Baloitcha E.
Source
Ocean Science, 2023,
19 (3), p. 535-558 ISSN 1812-0784
In this study, we use a joint observation-model approachto investigate the mixed-layer heat and salt annual mean as well as seasonalbudgets in the eastern tropical Atlantic. The regional PREFCLIM (PREFACE Climatology)observational climatology provides the budget terms with a relatively lowspatial and temporal resolution compared to the online NEMO (Nucleus for European Modelingof the Ocean; Madec, G., 2014) model, and thisis later resampled as in PREFCLIM climatology. In addition, advectionterms are recomputed offline from the model as PREFCLIM gridded advectioncomputation. In the Senegal, Angola, and Benguela regions, the seasonal cycle ofmixed-layer temperature is mainly governed by surface heat fluxes; however,it is essentially driven by vertical heat diffusion in the equatorial region.The seasonal cycle of mixed-layer salinity is largely controlled byfreshwater flux in the Senegal and Benguela regions; however, it follows thevariability of zonal and meridional salt advection in the equatorial and Angolaregions, respectively. Our results show that the time-averaged spatialdistribution of NEMO offline heat and salt advection terms compares much betterto PREFCLIM horizontal advection terms than the online heat and salt advectionterms. However, the seasonal cycle of horizontal advection in selectedregions shows that NEMO offline terms do not always compare well withPREFCLIM, sometimes less than online terms. Despite this difference, theseresults suggest the important role of small-scale variability in mixed-layerheat and salt budgets.
Plan de classement
Sciences fondamentales / Techniques d'analyse et de recherche [020]
;
Sciences du milieu [021]
;
Limnologie physique / Océanographie physique [032]
