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Satellite remote sensing techniques offer a wealth of optical, infrared (IR), and radar images of the ocean surface, where we can observe numerous elongated vortex structures known as filaments. These filaments become readily visible in the imagery due to the presence of surfactant films and/or floating algae clusters on the sea’s surface. Given their elongated form, automated vortex identification methods do not readily distinguish filaments from vortices. Nevertheless, both filaments and vortices exhibit notable characteristics such as high relative vorticity and kinetic energy. The process by which vortices transform into filaments is a result of their interaction with spatially non-uniform background currents. In this study, we apply the theoretical principles regarding the stretching of mesoscale ocean vortices to real ocean conditions, inferred from altimeter data. The primary objective of this research is to assess the proportion of mesoscale ocean vortices that undergo stretching to become filaments, consequently facilitating the redistribution of energy from the mesoscale to the submesoscale. We provide a total assessment of the portion of the World Ocean’s surface where mesoscale vortices undergo significant stretching. We present maps that indicate the geographical distribution of regions where vortex stretching is not restricted and offer an interpretation of the findings. The reduction in the inherent energy of vortices due to the stretching induced by the background flow is explained as a potential mechanism for energy transfer from the vortex to the flow, possibly leading to the manifestation of the negative viscosity effect within this system.
Translated title of the contributionТрансформация мезомасштабных океанических вихрей в филаменты: анализ данных альтиметрии
Original languageEnglish
Pages (from-to)8-31
JournalФУНДАМЕНТАЛЬНАЯ И ПРИКЛАДНАЯ ГИДРОФИЗИКА
Volume17
Issue number4
DOIs
StatePublished - 8 Jan 2025

ID: 129368280