High-Frequency Radar observation of strong and contrasted currents: the Alderney race paradigm

التفاصيل البيبلوغرافية
العنوان: High-Frequency Radar observation of strong and contrasted currents: the Alderney race paradigm
المؤلفون: Dumas, Dylan, Bennis, Anne-Claire, Guérin, Charles-Antoine, Lopez, Guiomar, Benoit, Laurent
سنة النشر: 2024
المجموعة: Physics (Other)
مصطلحات موضوعية: Physics - Atmospheric and Oceanic Physics
الوصف: The Alderney Race has been identified as a future site for the development of tidal energy, due to its bidirectional strong current reaching 5 m/s during spring tides. This hydrodynamics is very difficult to measure by in situ or remote sensing means. High-frequency coastal radars can provide a synoptic and near-real-time view of such a complex circulation, but the classical processing algorithms are not adapted to the extreme situation of strongly sheared currents. We propose an improved high-resolution direction-finding technique for the azimuthal processing of such radar data. It uses phased-array systems and combines the advantages of the usual beam-forming technique to eliminate many problems related to the distortion of Doppler spectra by extreme currents. The method is evaluated with a unique data set of radar measurements at two radar frequencies (13 and 24.5 MHz) and three spatial resolutions (200, 750, and 1500 m). The radar-based surface currents are analyzed in the light of a high-resolution numerical model and also compared with in situ measurements. While high azimuthal resolution can be achieved in this way, it is shown that the typical range resolutions of 750 and 1500 m are insufficient to account for the strong spatial variations of the surface current at some specific times and locations.
Comment: 26 pages, 15 figures, 3 tables
نوع الوثيقة: Working Paper
URL الوصول: http://arxiv.org/abs/2407.03827
رقم الأكسشن: edsarx.2407.03827
قاعدة البيانات: arXiv