Climate change directly affects the quality of fresh water as well as marine water. The possibilities may be:

1. Increase in temperature (Global warming) may increase evaporation thus concentrating the salts in both types of water. The salt content in water may increase slowly and slowly.

2. The reduction in rainfall may decrease the net volume of terrestrial water reaching the oceans and resulting in concentration of salts in marine water.

3. The melting of ice (due to elevated temperature) can cause more good quality water reaching the oceans and proving useful in significant quality changes.

4. Frequent floods may disturb the situation by bringing unwanted soil and solid material to rivers and oceans thus deteriorating quality of both type of waters 

You can also check the attached documents for further references. 

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