Salinity is also known to be a significant factor for deciding several characteristics of the chemistry of natural waters and biological processes. Along with that it also has its influence on the composition and movement of the sea: water and the distribution of fish and other marine resources.
Distribution of Salinity are in two ways :
Salinity of Ocean Regional Distribution
- Indian Ocean: The Indian Ocean has an average salinity of 35 parts per thousand. The low salinity in the Bay of Bengal is caused by the influx of river water from the Ganga.
- Arabian Sea: The Arabian Sea, on the other hand, has a higher salinity due to high evaporation and a low freshwater influx.
- Pacific Ocean: The Pacific Ocean’s salinity variation is primarily due to its shape and larger area extent.
The salinity of the Atlantic Ocean varies from 20 to 37 parts per thousand depending on location. - At equator: Near the equator, for example, there is heavy rainfall, high relative humidity, cloudiness, and the calm air of the doldrums.
- At polar regions: The polar regions, on the other hand, experience very little evaporation and receive large amounts of freshwater from ice melting. This results in low salinity levels ranging between 20 and 32 parts per thousand.
- At higher latitude: Despite its higher latitude, the North Sea has higher salinity due to more saline water brought by the North Atlantic Drift.
High evaporation: Due to high evaporation, the Mediterranean Sea has a higher salinity. This sea’s surface waters average around 38 parts per thousand. - Baltic Sea : The Baltic Sea has a low salinity due to a large influx of river waters, averaging around 35 parts per thousand.
- Black Sea: The Black Sea’s salinity is very low due to the massive freshwater influx from rivers, averaging around 13-23 parts per thousand.
FAQs Related with Regional Distribution Of Water Salinity Across The Oceans
Ques 1. What are the major regions with high salinity in the global ocean?
Ans. The global ocean exhibits regional variations in water salinity. Some major regions with high salinity include the subtropical regions, such as the subtropical North Atlantic and subtropical South Pacific. These areas experience high rates of evaporation, resulting in increased salinity levels.
Ques 2. Which regions of the ocean have lower salinity values?
Ans. Certain regions of the ocean display lower salinity values compared to others. These regions often coincide with areas influenced by significant freshwater inputs, such as river outflows or melting ice. Examples include the coastal regions near river mouths, such as the Amazon River in South America or the Ganges-Brahmaputra in the Bay of Bengal.
Ques 3. How do ocean currents contribute to the regional distribution of water salinity?
Ans. Ocean currents play a significant role in shaping the regional distribution of water salinity. They can transport water masses with varying salinity levels over long distances, influencing the salinity patterns in different regions. For instance, warm surface currents flowing towards high latitudes can bring relatively higher salinity water from the subtropical regions into polar areas, impacting the salinity distribution in those regions. Conversely, cold currents or upwelling zones can bring colder and less saline water to coastal areas, affecting the local salinity values.
Read Also : Why Is Salinity Important in the Ocean?