@article{fdi:010046011,
  title = {{S}ensitivity of the {A}tlantic {O}cean circulation to a hydraulic overflow parameterisation in a coarse resolution model : response of the subpolar gyre},
  author = {{B}orn, {A}. and {L}evermann, {A}. and {M}ignot, {J}uliette},
  editor = {},
  language = {{ENG}},
  abstract = {{W}e investigate the sensitivity of a coarse resolution coupled climate model to the representation of the overflows over the {G}reenland-{S}cotland ridge. {T}his class of models suffers from a poor representation of the water mass exchange between the {N}ordic {S}eas and the {N}orth {A}tlantic, a crucial part of the large-scale oceanic circulation. {W}e revisit the explicit representation of the overflows using a parameterisation by hydraulic constraints and compare it with the enhancement of the overflow transport by artificially deepened passages over the {G}reenland-{S}cotland ridge, a common practice in coarse resolution models. {B}oth configurations increase deep water formation in the {N}ordic {S}eas and represent the large-scale dynamics of the {A}tlantic realistically in contrast to a third model version with realistic sill depths but without the explicit overflow transport. {T}he comparison of the hydrography suggests that for the unperturbed equilibrium the {N}ordic {S}eas are better represented with the parameterised overflows. {A}s in previous studies, we do not find a stabilising effect of the overflow parameterisation on the {A}tlantic meridional overturning circulation but merely on the overflow transport. {A}s a consequence the surface air temperature in the {N}ordic {S}eas is less sensitive to anomalous surface fresh water forcing. {S}pecial attention is paid to changes in the subpolar gyre circulation. {W}e find it sensitive to the overflow transport and the density of these water masses through baroclinic adjustments. {T}he analysis of the governing equations confirms the presence of positive feedbacks inherent to the subpolar gyre and allows us to isolate the influence of the overflows on its dynamics.},
  keywords = {},
  booktitle = {},
  journal = {{O}cean {M}odelling},
  volume = {27},
  numero = {3-4},
  pages = {130--142},
  ISSN = {1463-5003},
  year = {2009},
  DOI = {10.1016/j.ocemod.2008.11.006},
  URL = {https://www.documentation.ird.fr/hor/fdi:010046011},
}