Sea surface salinity (SSS) is the measure of the salt concentration in the uppermost layer of the ocean.
Understanding Sea Surface Salinity (SSS)
According to scientific definitions, surface salinity (SSS) is the salt concentration in seawater. This concentration is precisely defined as the number of grams of salt dissolved in 1000 grams of water. It's a crucial physical property of seawater, influencing its density, temperature, and circulation patterns.
Measurement Units
The salt concentration in seawater is typically expressed using specific units to provide a clear and standardized measurement. Based on this definition:
- One gram of salt per 1000 grams of water is equivalent to one unit.
These units are commonly known as:
- Practical Salinity Unit (PSU)
- Part Per Thousand (PPT)
Both PSU and PPT represent the same ratio: grams of salt per thousand grams of water. Understanding these units is key to interpreting oceanographic data related to salinity.
Salinity varies across the globe, influenced by factors like evaporation, precipitation, river discharge, and ice formation/melting. Higher evaporation and lower precipitation tend to increase salinity, while the opposite decreases it.
