INTERNAL SOLITARY WAVES IN THE RED SEA AN UNFOLDING MYSTERY

• Type: Article in International Scientific Journal
• Date: 2012

Authors

Jose C B da Silva (Author) FCUP; Jorge M Magalhaes (Author) Other; Theo Gerkema (Author) Other; Leo R M Maas (Author) Other

Journal

Title: Oceanography

Vol. 25

Pages: 96-107

ISSN: 1042-8275

Publisher: Oceanography Society

Indexing

ISI Web of Knowledge - 21 Citations

Scopus - 24 Citations

Scientific classification

FOS: Natural sciences > Earth and related Environmental sciences

Other information

Authenticus ID: P-002-95Y

DOI: 10.5670/oceanog.2012.45

Abstract (EN): The off-shelf region between 16.0 degrees and 16.5 degrees N in the southern Red Sea is identified as a new hotspot for the occurrence of oceanic internal solitary waves. Satellite observations reveal trains of solitons that, surprisingly, appear to propagate from the center of the Red Sea, where it is deepest, toward the continental shelf, but they do not survive as coherent structures over the shelf. These solitons are characterized by coherent crest lengths exceeding 80 km and crest-to-crest distances of more than 2 km, compatible with signatures of large-amplitude solitary waves. Despite the fact that these Red Sea solitons have large amplitudes, they appear to be generated by very weak surface tides. Tidal current velocity is only about 5 cm s(-1) over the shelf, much weaker than over other ocean shelves where similar solitary waves have been reported. The appearance of these waves over this particular geographical stretch suggests generation by a locally amplified internal tide on the main pycnocline. We consider three possible explanations for soliton generation in the Red Sea: interfacial tide resonance, local generation by internal tidal beams generated at the shelf breaks, and local generation by internal tidal beams generated at the shelf breaks but first amplified by repeated focusing reflections.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 12