Modeling results of an upwelling in an idealized submarine canyon under different stratified conditions

submarine canyons along the coast play a major role in upwelling dynamics. on the one hand, various numerical studies and observations have suggested a depth origin of upwelling in submarine canyons between 100 and 400 m deep. on the other hand, recent observations in the cassidaigne canyon, northwest of the mediterranean sea, show wind-driven transient upwelling of water at depths of over 1600 m.the potential impact of interior stratification on upwelling depths in submarine canyons is investigated using croco numerical simulations. a 6-day alongshore upwelling-favorable wind is considered. the dataset gathers the results of three idealized simulations: a coastal shelf slope without any canyon under non-stratified condition; a coastal slope with a canyon under non-stratified condition (analog to the particular case of the mediterranean sea); a coastal slope with a canyon under stratified condition (comparable to the stratification in most oceanic areas).the results highlight a control of the upwelling flow and depth with the stratification. a non-stratified water column leads to upwelling over the entire water column, from the deep sea to the mixed layer depth. a stronger stratification results in a tilting of the isopycnals at the canyon head as a response of free surface elevation. this adjusment eliminates pressure gradients in the canyon body, essential for generating upwellings in canyons, and then limits deep currents.the numerical code configuration (croco) is provided.

沿岸海底峡谷在上升流动力学中扮演着举足轻重的角色。一方面，众多数值模拟与观测研究均表明，海底峡谷中上升流的起源深度介于100至400米之间。另一方面，近期对位于地中海西北部的卡西迪安峡谷的观测显示，在超过1600米的深度处出现了由风驱动的暂时性上升流。本研究利用克罗科数值模拟方法，探讨了内部层结对海底峡谷上升流深度的潜在影响。考虑了持续6天的沿岸上升流有利风向。数据集汇集了三次理想化模拟的结果：无峡谷的沿岸大陆架斜坡在非层结条件下的情况；具有峡谷的沿岸大陆架斜坡在非层结条件下的情况（类似于地中海的特定案例）；具有峡谷的沿岸大陆架斜坡在层结条件下的情况（与大多数海洋区域的层结相似）。结果显示，层结对上升流流动和深度的控制作用显著。非层结的水柱会导致从深海至混合层深度的整个水柱发生上升流。更强的层结会导致峡谷头部等深线发生倾斜，这是对自由水面高程响应的结果。这种调整消除了峡谷体内的压力梯度，这对于在峡谷中产生上升流至关重要，并随后限制了深层水流。提供了数值代码配置（克罗科）。