Question: You study the internal waves in the equatorial Atlantic sea because they are especially strong there. But are they not strong also at the other geographical latitudes- e.g in the tropics, at the other polar circle etc.?

  1. Hi kisi19chan,
    yes internal waves are present at all latitudes, however at each latitude only some “frequencies” can survive (I do not know if you know what the frequency of a wave is, in short is how fast it oscillates, however, just ask if you want to understand it better, or maybe you already studied that in class?).
    At the Equator, the largest set of frequencies survives, and this is the reason why they are thought to play a special role at the low latitudes, and not, for example, at the Poles.
    Why at the low latitudes the surviving frequencies are more than at the Pole?
    This has to do with the location of the Equator and the Poles with respect to the rotation axis of the Earth. In fact if you stand at the north pole, gravity is pointing from your head to your feet, and is parallel to the rotation axis of the Earth. However, if you stand right at the Equator, gravity is still pointing down from your head to your feet, but now is perpendicular to the rotation axis!
    Waves “feel” this difference much more than us, and for this reason, a larger range of frequencies for internal waves can survive at the Equator, but not at the Poles!
    Moreover, at the Equator we do observe strong currents for which we do not have yet a clear explanation, so I am trying to figure out if internal wave presence and strong currents are somehow related.
    I hope this answers your question, although I must say that this is a very though on, so if you want to know more or understand better, do not hesitate to ask more! thanks!