Ocean Dynamics

, Volume 59, Issue 4, pp 539–549 | Cite as

Effects of the air–sea coupling time frequency on the ocean response during Mediterranean intense events

  • Cindy Lebeaupin Brossier
  • Véronique Ducrocq
  • Hervé Giordani


The near-sea surface meteorological conditions associated with the Mediterranean heavy precipitation events constitute, on a short time scale, a strong forcing on the ocean mixed layer. This study addresses the question of the optimal time frequency of the atmospheric forcing to drive an ocean model in order to make it able to capture the fine scale ocean mixed layer response to severe meteorological conditions. The coupling time frequency should allow the ocean model to reproduce the formation of internal low-salty boundary layers due to sudden input of intense precipitation, as well as the cooling and deepening of the ocean mixed layer through large latent heat fluxes and stress under the intense low-level jet associated with these events. In this study, the one-dimensional ocean model is driven by 2.4-km atmospheric simulated fields on a case of Mediterranean heavy precipitation, varying the time resolution of the atmospheric forcing. The results show that using a finer temporal resolution than 1 h for the atmospheric forcing is not necessary, but a coarser temporal resolution (3 or 6 h) modifies the event course and intensity perceived by the ocean. Consequently, when using a too coarse temporal resolution forcing, typically 6 h, the ocean model fails to reproduce the ocean mixed layer fine scale response under the heavy rainfall pulses and the strong wind gusts.


Air-sea coupling Mediterranean Sea Mesoscale modeling Temporal resolution 



This work has been sponsored by the “CYclogénèse et PRécipitations Intenses en Méditerranée” (CYPRIM) project of the program ACI-FNS “Aléas et Changements Globaux” of the French research ministry. The authors would like to thank the two anonymous journal reviewers for their constructive comments.


  1. Alexander MA, Scott JD, Deser C (2000) Processes that influence sea surface temperature and ocean mixed layer depth variability in a coupled model. J Geophys Res 105(C7):16823–16842CrossRefGoogle Scholar
  2. Ayoub N, Lucas M, Barnier B, Penduff T, Valladeau G, De Mey P (2006) A study of model errors in surface layers due to uncertainties in the atmospheric fields. Mercator Ocean Q Newsl 22:29–38Google Scholar
  3. Bahurel P, Dombrowsky E, Lellouche J-M, and the Mercator project team (2004) Mercator ocean monitoring and forecasting system, near-realtime assimilation of satellite and in-situ data in different operational ocean models. In: 36th international Liège Colloquium on ocean dynamics, Liège, April 2004 (preprints)Google Scholar
  4. Barnier B, Brodeau L, Penduff T (2006) News: ocean surface forcing and surface fields. Mercator Ocean Q Newsl 22:4–7Google Scholar
  5. Bernie DJ, Woolnough SJ, Slingo JM, Guilyardi E (2005) Modeling diurnal and intraseasonal variability of the Ocean Mixed Layer. J Clim 18:1190–1202CrossRefGoogle Scholar
  6. Blanke B, Delecluse P (1993) Variability of the tropical Atlantic ocean simulated by a general circulation model with two different mixed-layer physics. J Phys Oceanogr 23:1363–1388CrossRefGoogle Scholar
  7. Brainerd KE, Gregg MC (1995) Surface mixed and mixing layer depths. Deep-sea Res Part I 42:1521–1543CrossRefGoogle Scholar
  8. Brandt P, Funk A, Czeschel L, Eden C, Boning CW (2007) Ventilation and transformation of labrador sea water and its rapid export in the deep Labrador current. J Phys Oceanogr 37:946–961CrossRefGoogle Scholar
  9. Ducrocq V, Ricard D, Lafore J-P, Orain F (2002) Storm-scale numerical rainfall prediction for five precipitating events over France: on the importance of the initial humidity field. Weather Forecast 17(6):1236–1256CrossRefGoogle Scholar
  10. Ekman VW (1905) On the influence of the Earth’s rotation on ocean currents. Ark Mat Astron Fys 2:1–53Google Scholar
  11. Estournel C, Durrieu de Madron X, Marsaleix P, Auclair F, Julliand C, Vehil R (2003) Observation and modelling of the winter coastal oceanic circulation in the Gulf of Lion under wind conditions influenced by the continental orography (FETCH experiment). J Geophys Res 108(C3):8059. doi: 10.1029/2001JC000825.CrossRefGoogle Scholar
  12. Fairall CW, Bradley EF, Hare JE, Grachev AA, Edson JB (2003) Bulk parameterization of air-sea fluxes : updates and verification for the COARE algorithm. J Climate 16:571–591CrossRefGoogle Scholar
  13. Gaspar P, Grégoris Y, Lefevre J-M (1990) A simple Eddy Kinetic Energy model for simulations of the oceanic vertical mixing: tests at station papa and long-term upper ocean study site. J Geophys Res 95(C9):16179–16193CrossRefGoogle Scholar
  14. Giordani H, Caniaux G, Prieur L, Paci A, Giraud S (2005) A 1 year mesoscale simulation of the northeast Atlantic: mixed layer heat and mass budgets during the POMME experiment. J Geophys Res 110:C07S08. doi: 10.1029/2004JC002765.CrossRefGoogle Scholar
  15. Giordani H, Prieur L, Caniaux G (2006) Advanced insights into sources of vertical velocity in the ocean. Ocean Dyn 56:513–524CrossRefGoogle Scholar
  16. Herrmann M, Somot S (2008) Relevance of ERA40 dynamical downscaling for modeling deep convection in the North-Western Mediterranean Sea. Geophys Res Lett 35:L04607. doi: 10.1029/2007GL032442.CrossRefGoogle Scholar
  17. Hontarrède M, Jourdan R, Vaysse F, Valantin P-Y (2004) Tempête dans le golfe du lion. Metmar 203:6–9Google Scholar
  18. Lafore J-P, Stein J, Asencio N, Bougeault P, Ducrocq V, Duron J, Fischer C, Héreil P, Mascart P, Masson V, Pinty J-P, Redelsperger J-L, Richard E, Vilà-Guerau de Arellano J (1998) The Meso-NH atmospheric simulation system. Part I: adiabatic formulation and control simulations. Scientific objectives and experimental design. Ann Geophys 16(1):90–109CrossRefGoogle Scholar
  19. Lebeaupin C, Ducrocq V, Giordani H (2006) Sensitivity of Mediterranean torrential rain events to the sea surface temperature based on high-resolution numerical forecasts. J Geophys Res 111:D12110. doi: 10.1029/2005JD006541.CrossRefGoogle Scholar
  20. Lebeaupin Brossier C, Ducrocq V, Giordani H (2008) Sensitivity of three Mediterranean heavy rain events to two different sea surface fluxes parameterizations in high-resolution numerical modeling. J Geophys Res 113:D21109. doi: 10.1029/2007JD009613.CrossRefGoogle Scholar
  21. Lebeaupin Brossier C, Ducrocq V, Giordani H (2009) Two-way one-dimensional high-resolution air–sea coupled modelling applied to Mediterranean heavy rain events. Q J R Meteorol Soc 135:187–204CrossRefGoogle Scholar
  22. Li L, Bozec A, Somot S, Béranger K, Bouruet-Aubertot P, Sevault F, Crépon M (2006) Regional atmospheric, marine processes and climate modelling. In: Lionello P, Malanotte-Rizzoli P, Boscolo R (eds) Mediterranean climate variability and predictability. Elsevier, Amsterdam, pp 373–397Google Scholar
  23. Mlawer EJ, Taubman SJ, Brown PD, Iacono MJ, Clough SA (1997) A validated correlated-k model for the longwave. J Geophys Res 102:16663–16682CrossRefGoogle Scholar
  24. Nuissier O, Ducrocq V, Ricard D, Lebeaupin C, Anquetin S (2008) A numerical study of three catastrophic precipitating events over Western Mediterranean region (Southern France). Part I: numerical framework and synoptic ingredients. Q J R Meteorol Soc 134:111–130CrossRefGoogle Scholar
  25. Paci A, Caniaux G, Gavart M, Giordani H, Lévy M, Prieur L, Reverdin G (2005) A high-resolution simulation of the ocean during the POMME experiment: simulation results and comparison with observations. J Geophys Res 110:C07S09. doi: 10.1029/2004JC002712 CrossRefGoogle Scholar
  26. Paci A, Caniaux G, Giordani H, Lévy M, Prieur L, Reverdin G (2007) A high-resolution simulation of the ocean during the POMME experiment: mesoscale variability and near surface processes. J Geophys Res 112:C04007. doi: 10.1029/2005JC003389 CrossRefGoogle Scholar
  27. Pinty J-P, Jabouille P (1998) A mixed-phase cloud parameterization for use in a mesoscale non-hydrostatic model: simulations of a squall line of orographic precipitation. In: Conference on cloud physics. American Meteorological Society, Everett, pp 217–220Google Scholar
  28. Xing J, Davies AM, Fraunié P (2004) Model studies of near-inertial motion on the continental shelf off norteast Spain: a three-dimensional/two-dimensional/one-dimensional model comparison study. J Geophys Res 109:C01017. doi: 10.1029/2003JC001822 CrossRefGoogle Scholar

Copyright information

© Springer-Verlag 2009

Authors and Affiliations

  • Cindy Lebeaupin Brossier
    • 1
  • Véronique Ducrocq
    • 1
  • Hervé Giordani
    • 1
  1. 1.Centre National de Recherches Météorologiques/Groupe d’étude de l’Atmosphère MétéorologiquE (Météo-France/CNRS)Toulouse cedexFrance

Personalised recommendations