How The Moon Impacts Subsea Communication Cables

By Keith Cowing
Status Report
April 29, 2023
Filed under , ,
How The Moon Impacts Subsea Communication Cables
a) Measured Phase Difference (MPD) over 12 days relative to aggregated tide (AT, computed with GOT4.7). b) MPD-uncorrelated and small environmental temperature changes at setup. c) Wavelength drift of ECL recorded every 60s (dark) and averaged over 600s (light). d) Simple tide model: when all objects line up maximum (spring) tides with semidiurnal period result; with the Moon perpendicular to the Sun-Earth axis, the semidiurnal tide signature weakens. — physics.geo-ph

Here we report, for the first time, on cable length variations in the sub-meter range that depend on water pressure generated by tidal variations.

In contrast to the two aforementioned implementations, the cable is not impacted by any kind of abrupt sea floor motions. However, changes in local water pressure cause cable length changes that are detectable with an ultra-stable phase meter. In contrast to commonly held views, subsea cables diverge from the ‘loose tube’ model that suggests a forceless bearing on the fibers. Our observations indicate a strong coupling between the cable jacket and the sheathed fiber.

Lothar Moeller

Subjects: Signal Processing (eess.SP); Instrumentation and Methods for Astrophysics (astro-ph.IM); Atmospheric and Oceanic Physics (; Geophysics (physics.geo-ph)
Cite as: arXiv:2304.06905 [eess.SP](or arXiv:2304.06905v1 [eess.SP] for this version)
Submission history
From: Lothar Moeller
[v1] Fri, 14 Apr 2023 02:38:28 UTC (680 KB)

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