%0 Journal Article
%9 ACL : Articles dans des revues avec comité de lecture répertoriées par l'AERES
%A Conejero, C.
%A Renault, Lionel
%A Desbiolles, Fabien
%A Giordani, H.
%T Unveiling the influence of the daily oceanic (sub)mesoscale thermal feedback to the atmosphere
%D 2025
%L PAR00029879
%G ENG
%J Journal of Physical Oceanography
%@ 0022-3670
%K Mesoscale processes ; Frontogenesis/frontolysis ; Sea surface temperature ; Air-sea interaction ; Feedback ; Coupled models
%M ISI:001545703100001
%N 8
%P 1009-1032
%R 10.1175/jpo-d-24-0247.1
%U https://www.documentation.ird.fr/hor/PAR00029879
%V 55
%W Horizon (IRD)
%X Oceanic mesoscale [O(100) km] thermal feedback (TFB) can modify the marine atmospheric boundary layer through two main mechanisms: downward momentum mixing (DMM) and pressure adjustment (PA). In this study, we use ERA5 reanalysis, with the finest spatial resolution available (roughly 25 km globally), and a set of coupled ocean-atmosphere model experiments to investigate the extent to which the spatial resolution of oceanic fine-scale structures [O(10)-(100) km] influences the TFB mechanisms on a daily time scale in the northwestern tropical Atlantic. We show that the low-level wind magnitude response to sea surface temperature anomalies is controlled by large oceanic mesoscale structures (>100 km), whereas finer structures play a minor role. However, the TFB mechanisms vary considerably depending on whether the mesoscale structures are fully represented or not. The DMM and PA mechanisms are diminished by about 36% and 85%, respectively, when the full range of mesoscale structures in the ocean is resolved. This reduction is associated with both a stronger atmospheric frontogenesis mechanism induced by submesoscale [O(10) km] oceanic thermal structures and the divergence of submesoscale ocean currents, which is not the case at the large mesoscale. These processes have the potential to exert a destructive influence on the daily oceanic mesoscale TFB by inducing opposite low-level atmospheric vertical velocities, which is particularly enhanced in the case of the PA mechanism. Finally, our findings suggest that climate models must accurately represent fine-scale ocean thermal structures that directly influence TFB mechanisms and potentially affect cloud formation and precipitation patterns.
%$ 032 ; 020