The vertical profiles of salinity show distinct water parcels that sink and/or rise as a response to the intense heat fluxes. In comparison to the open-ocean water column, wake waters are strongly stratified with respect to temperature although highly unstable. To characterize the convective layer (25-70m) developing within the oceanic wake, 200 vertical profiles of temperature, salinity and turbulence were considered, together with the computation of the Density Ratio and Turner-angle. This study considers in-situ, remote sensing, and ocean circulation model data, to investigate the effects of the warm wake in the vertical structure of the upper ocean. This phenomenon detectable from space can extend 100 km offshore of Madeira, where the sea surface temperature can be 4⁰C higher than the surrounding oceanic waters. As a consequence, a warm oceanic wake forms on the leeward side. In addition to weaker winds, the wake is also characterized by a clearing of clouds, resulting in intense solar radiation reaching the sea surface. The interaction between the incoming winds with high mountainous islands produces a wind-sheltered area in the leeward side, known as the atmospheric wake. This cycle is consistent with mesoscale wind conditions and local inversion height patterns. The analysis shows a pronounced annual cycle with an increasing vortex-shedding rate from April to August and a sudden decrease in September. The algorithm is based on a set of criteria and enabled us to develop a climatology of vortex shedding from Madeira Island for the 10-year simulation period. As part of the case study, we developed a vortex identification algorithm. Our results show a strong dependency of vortex shedding on local and synoptic-flow conditions, which are to a large extent governed by the location, shape and strength of the Azores high. The simulation compares well with satellite and aerial observations and with existing literature on idealised simulations. Basic properties of vortex streets were analysed and validated through a 6 d long case study in the lee of Madeira Island. Using the non-hydrostatic limited-area COSMO model driven by the ERA-Interim reanalysis, we conducted a 10-year-long simulation over a mesoscale domain covering the Madeira and Canary archipelagos at high spatial (grid spacing of 1 km) and temporal resolutions. Observational evidence comes from case studies and satellite imagery, but the climatology and annual cycle of vortex shedding are often poorly understood. Atmospheric vortex streets are a widely studied dynamical effect of isolated mountainous islands.
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