The tranquil sea

Abstract

Let us now engage in a fairly general overview of the seas and oceans, which we shall attempt to demystify by interjecting some anecdotes from their history—a history that is closely linked to that of Earth itself. As we did with the atmosphere, we start by examining the state of this immense mass of water, more or less salted depending on the particular region of the globe and sufficiently dense to prevent light from reaching its great depths, thereby retaining a part of their mystery. To observe these seas they must be navigated, which brings to our attention the remarkable stability of surface ships compared with submarines. We give a panorama synopsis of the gigantic thermohaline circulation, whose best-known part is theGulf Stream in the North Atlantic. Slowly but surely, with its power and inertia, this large marine loop drains the five oceans and constitutes the main current about which agitate multiple secondary currents that operate on the scales of the individual seas. We start by observing this global circulation and leave for the next chapter the fluctuations that ceaselessly perturb it throughout its course.

The sea is the vast reservoir of Nature. The globe began with sea, so to speak; and who knows if it will not end with it? In it is supreme tranquillity.

(Jules Verne, Twenty Thousand Leagues under the Sea)