Water salinity, the measure of salt concentration in water, is affected by a balance of processes that either increase or decrease it.
Factors Increasing Salinity
These processes add salts to the water:
- Evaporation of Ocean Water: When ocean water evaporates, the water turns into vapor, leaving behind the dissolved salts. This increases the concentration of salt in the remaining water, as stated in the provided reference.
- Formation of Sea Ice: As seawater freezes to form sea ice, the salt is mostly excluded from the ice structure. The surrounding unfrozen water becomes saltier.
Factors Decreasing Salinity
These processes dilute the salt concentration in water:
- Input of Fresh Water from Rivers: Rivers carry fresh water from land into the oceans. This freshwater dilutes the salt concentration, reducing the salinity of ocean water.
- Precipitation of Rain and Snow: Rain and snow, which are fresh water, dilute the ocean's salt concentration when they fall directly onto the water or flow into it from land.
- Melting of Ice: When icebergs and glaciers melt, they release fresh water that dilutes the ocean's salinity.
Summary Table
| Process | Effect on Salinity |
|---|---|
| Evaporation of ocean water | Increases |
| Formation of sea ice | Increases |
| Input of fresh river water | Decreases |
| Precipitation (rain, snow) | Decreases |
| Melting of ice | Decreases |
In conclusion, water salinity is a dynamic property, influenced by multiple factors that constantly adjust the balance between salt concentration and dilution.
