@article{fdi:010084274,
  title = {{C}ompetition between baroclinic instability and {E}kman transport under varying buoyancy forcings in upwelling systems : an idealized analog to the {S}outhern {O}cean},
  author = {{T}homsen, {S}. and {C}apet, {X}. and {E}chevin, {V}incent},
  editor = {},
  language = {{ENG}},
  abstract = {{C}oastal upwelling rates are classically determined by the intensity of the upper-ocean offshore {E}kman transport. {B}ut (sub)mesoscale turbulence modulates offshore transport, hence the net upwelling rate. {E}ddy effects generally oppose the {E}kman circulation, resulting in so-called "eddy cancellation," a process well studied in the {S}outhern {O}cean. {H}ere we investigate how air-sea heat/buoyancy fluxes modulate eddy cancellation in an idealized upwelling model. {W}e run {CROCO} simulations with constant winds but varying heat fluxes with and without submesoscale-rich turbulence. {E}ddy cancellation is consistently evaluated with three different methods that all account for the quasi-isopycnal nature of ocean circulation away from the surface. {F}or zero heat fluxes the release of available potential energy by baroclinic instabilities is strongest and leads, near the coast, to nearly full cancellation of the {E}kman cross-shore circulation by eddy effects, i.e., zero net mean upwelling flow. {W}ith increasing heat fluxes eddy cancellation is reduced and the transverse flow progressively approaches the classical {E}kman circulation. {S}ensitivity of the eddy circulation to synoptic changes in air-sea heat fluxes is felt down to 125-m depth despite short experiments of tens of days. {M}esoscale dynamics dominate the cancellation effect in our simulations which might also hold for the real ocean as the relevant processes act below the surface boundary layer. {A}lthough the idealized setting overemphasizes the role of eddies and thus studies with more realistic settings should follow, our findings have important implications for the overall understanding of upwelling system dynamics.},
  keywords = {{E}kman pumping/transport ; {E}ddies ; {U}pwelling/downwelling ; {T}urbulence ; {V}ertical motion ; {B}aroclinic flows ; {B}uoyancy ; {I}dealized models ; {OCEAN} {AUSTRAL}},
  booktitle = {},
  journal = {{J}ournal of {P}hysical {O}ceanography},
  volume = {51},
  numero = {11},
  pages = {3347--3364},
  ISSN = {0022-3670},
  year = {2021},
  DOI = {10.1175/jpo-d-20-0294.1},
  URL = {https://www.documentation.ird.fr/hor/fdi:010084274},
}