1 Situation in which, over a given lapse of time, more air flows into a given region than flows out of it. It is commonly accompanied by confluence of the streamlines, but may be caused by differences of velocity, e.g. where the wind comes against a coast or a mountain wall. Surface friction can produce convergence. Compare divergence.
2 The point, line, or region where two oceanic water masses or surface currents meet. This leads to the denser water from one side sinking beneath the lighter water of the other side.