More than 97 percent of the earth’s water is salty sea water.
The ocean has a salinity of about 35 parts per thousand (ppt), or 3.5%.
All of the earth’s freshwater, water found in ice caps, lakes, rivers, and as groundwater, which is water found close to the surface, in wells and aquifers, accounts for the remaining 3 percent.
It is a common misconception is that the ocean is blue because the sky is blue.
In fact, the main reason why the ocean is blue is because water absorbs red light from the sun, and the very slight blue color we see in water can only be seen in large volumes.