%0 Journal Article
%9 ACL : Articles dans des revues avec comité de lecture répertoriées par l'AERES
%A Vincent, E. M.
%A Emanuel, K. A.
%A Lengaigne, Matthieu
%A Vialard, Jérôme
%A Madec, G.
%T Influence of upper ocean stratification interannual variability on tropical cyclones
%D 2014
%L fdi:010062682
%G ENG
%J Journal of Advances in Modeling Earth Systems
%@ 1942-2466
%K ZONE TROPICALE
%M ISI:000344387900012
%N 3
%P 680-699
%R 10.1002/2014ms000327
%U https://www.documentation.ird.fr/hor/fdi:010062682
%> https://www.documentation.ird.fr/intranet/publi/2014/12/010062682.pdf
%V 6
%W Horizon (IRD)
%X Climate modes, such as the El Nino Southern Oscillation (ENSO), influence Tropical Cyclones (TCs) interannual activity through their effect on large-scale atmospheric environment. These climate modes also induce interannual variations of subsurface oceanic stratification, which may also influence TCs. Changes in oceanic stratification indeed modulate the amplitude of TCs-induced cooling, and hence the negative feedback of air-sea interactions on the TC intensity. Here we use a dynamical downscaling approach that couples an axisymmetric TC model to a simple ocean model to quantify this interannual oceanic control on TC activity. We perform twin experiments with contrasted oceanic stratifications representative of interannual variability in each TC-prone region. While subsurface oceanic variations do not significantly affect the number of moderate (Category 3 or less) TCs, they do induce a 30% change of Category 5 TC-days globally, and a 70% change for TCs exceeding 85 m s(-1). TCs in the western Pacific and the southwestern Indian Ocean are most sensitive to oceanic interannual variability (with a similar to 10 m s(-1) modulation of the intensity of strongest storms at low latitude), owing to large upper ocean variations in response to ENSO. These results imply that a representation of ocean stratification variability should benefit operational forecasts of intense TCs and the understanding of their climatic variability.
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