Salinity is directly positively related to seawater density.On an average, seawater density increases with increasing salinity and vice versa.E.g. Density of pure water is 1.00 g/cm3 and density of water with 35% salinity is 1.028 g/cm3.
The Stratosphere is the layer of the Earth’s atmosphere which lies beyond the troposphere. It extends up to an altitude of 50 kilometres from the earth’s surface. This layer is almost free from clouds and associated weather phenomenon. It therefore makes conditions most ideal for flying aeroplanes.