Does anyone know when a river reaches its mouth, why does its energy decrease? - what happens to its discharge

Answer 1

It is trying to push into another body of water that is not moving in its direction and which has inertia that resists that inflow. The waters of the river and its destination mix at the discharge but the river's flow is broken up from its earlier steady flow.

Answer 2

When flying over the English channel I have noticed what looks like rivers flowing in the sea. I believe this is the continuing outflow from rivers even though this continues several km from the coastline The effect is not a colour change more a difference in the wave patterns. I assume that the fresh water entering the sea having a different density to the sea water results in a different wave pattern which can be seen plainly.

Answer 3

Water runs downhill. When it reaches the bottom the terrain is flattened out and the flow is less channelized. This is called the delta of the river. Sometimes it mirrors the source, many streams making one river which diverts into many streams at the end of the journey. As always, there are exceptions to the rule. The power of the Congo, and the Amazon produce powerful turbidity currents which pump oxygen rich water into the ocean. Think of an injection. This, is one of the principle sources of oxygen on the planet.

Answer 4

Well I guess it's a gravity/potential energy issue: A river's source is generally high in the hills/mountains, so the mass of the water has potential energy due to the earth's gravitational pull. So the higher up the hill from sea level, the more energy it has. As the water flows down hill towards the sea it looses potential energy until it reaches sea level where its potential energy becomes zero... it cant flow any further down hill.
The loss or discharge of potential energy is due to the movement of the water in the first place, this being kinetic energy.

Answer 5

Its to do with its volume on reaching the open sea which has a greater volume of water, the rivers discharge rate into the sea increases, thats why you get the swirl of the water at the mouth of the river.

Answer 6

As rivers near the sea, the fall of the land decreases, rivers spread out and flow gently into the sea. In Antalya, Turkey, there is a river which plunges off a cliff-top straight into the sea. It's not a huge drop, but it's still impressive.