Apparently a bouy near the African coast registered a 2000 metre drop. This is what you'd see if a huge wave was approaching, as the water gets sucked out rapidly. I was thinking of equipment malfunction until I saw that confirmation.
What with the recent eclipse and big trouble in Brazil, Gaza and Ukraine, it reminds me of this biblical quote:
25 And there shall be signs in the sun, and in the moon, and in the stars; and upon the earth distress of nations, with perplexity; the sea and the waves roaring;
