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Level of Salinity in The Ocean Will Make You Shocked

by Rini

The definition of salinity is the level of salinity or the level of salt dissolved in water. Salinity can also refer to the salt content in the soil. The salt content in most seawater, lakes, rivers, and natural waterways is so small that the water in this place is categorized as fresh water. The actual salt content in seawater, by definition, is less than 0.05%. Above that, water is categorized as brackish water or becomes saline if the concentration is 3 to 5%. More than 5%, it is called brine. The most complete eight characteristics of the Pacific Ocean.

Natural seawater is saline water with a salt content of around 3.5%. Some salt lakes on land and some oceans have a higher salinity than most seawater. For example, the Dead Sea contains salt around 30%. Although most seawater in the world has a salt content of around 3.5%, seawater also varies in salt content. To find out more clearly about the level of salinity in the ocean, here is an explanation:

Theory Regarding the Origins of Salt in the Sea

At first, it was estimated that the chemicals that cause salty seawater originated from land carried by rivers flowing into the sea, whether from erosion of terrestrial rocks, from landslides, from rainwater or from other natural phenomena, which is carried by river water to the sea. If this is true; of course, the chemistry of river water will not be different from the chemical makeup of seawater. The effects of natural disasters on the Ocean that can cause harm.

In theory, the salt substances originated from the bottom of the sea through an outgassing process, namely seepage from the earth’s skin on the seabed in the form of gas to the surface of the sea floor. Together with these gases, the dissolution of the earth’s crust is dissolved and together these salts also seep water, all in a constant ratio so that salt is formed in the sea. This salt content has remained unchanged throughout the period, meaning that sea water is increasingly salty.

Dissolved substances that form salts, whose levels are measured in terms of salinity can be divided into four groups, namely:

1. The main constituents: Cl, Na, SO4, and Mg.

2. Dissolved gases: CO2, N2, and O2.

3. Nutrient Elements: Si, N, and P.

4. Runout elements: I, Fe, Mn, Pb, and Hg.

Distribution of Salinity in the Sea 

Next, the level of salinity in the ocean is the spread. Salinity distribution in the sea is influenced by various factors such as water circulation patterns, evaporation, rainfall, river flow. Estuary waters or areas around Kuala can have complex salinity structures, because in addition to being a meeting between relatively lighter fresh water and heavier sea water, also water stirring is crucial. Hence the effects of ocean noise pollution on marine animals you should know.

  • The first is that waters with very strong salinity stratification occur where fresh water is a thin layer on the surface while underneath there is sea water. This can be found in front of the river mouth where the flow is strong while the tidal influences are small.
  • Second, are waters with moderate stratification. This occurs because of the tidal motion that causes stirring in the water column until a vertical water exchange occurs. On the surface, water tends to flow out while seawater creeps in from below. Between the two occurring mixing, the result is that the line of isohaline lines connecting the same salinity have an inclined direction. Such conditions can also be found in several estuary glasses of water in Sumatra.
  • Third, salinity in the subpolar region is the area above the subtropical region to approach the lower pole on the surface and increase in a fixed (monotonous) depth. Meanwhile, in the tropics, the surface salinity is lower than in-depth due to high precipitation or rainfall.

Determination of salinity value

To find out about the level of salinity in the ocean, here is the determination of the value of salinity. The most distinctive feature of seawater that is known to everyone is its salty taste. This is because, in dissolved seawater various kinds of salt, the most important is Sodium chloride (NaCl) which is often also called salt. The effects of Ocean acidification on Aquatic organisms.

In addition to Sodium chloride, in seawater, there are also magnesium salts, calcium, potassium and so on. In the oceanology literature, it is known as salinity (often called salinity or salinity), which means the amount of weight of all salts (in salt) dissolved in one liter of water, usually expressed in units of 0/00 (per mile, grams per liter).

Chemically to determine the salinity value is done by calculating the amount of chlorine in seawater samples. This is done because it is very difficult to determine the salinity of the whole dissolved compound. Therefore only a review of the largest component is chloride (Cl).

Seawater has an average level of 35 ppt but can range between 30-40 ppt. This occurs because of differences in evaporation, rainfall, freezing, and runoff of fresh water from the land in different latitudes and locations. Seawater salinity also varies with water depth because the density of water and pressure increases with depth. Water with salinity above 50 ppt is salt water, although not many organisms can survive in high salt concentrations. Finding the differences between sea wave and ocean flow.

The impact of salinity on the lives of marine animals and so on is some plants and animals that are able to control their body’s salt levels, while others change with water. However, because wind can bring salt to the ground, salinity is also an important factor for land plants and animals in coastal areas. Salinity not only determines where you will find certain organisms but also affects the overall ocean currents of the earth and weather patterns.

Factors that affect salinity 

  • Evaporation, the greater the rate of evaporation of sea water in an area, the higher the salinity and vice versa in areas with low levels of seawater evaporation, then the area is low in salt.
  • Rainfall, the greater or a lot of rainfall in an area of the sea, the salinity of the sea water will be low and vice versa the less or less rainfall that will decrease salinity will be high.
Water Salinity Based on Percentage of Dissolved Salt
Freshwater Brackish water Saline Water Brine
< 0.05 % 0.05 – 3 % 3 – 5 % > 5 %

Soluble substances include inorganic salts, organic compounds derived from living organisms, and dissolved gases. The main salts found in seawater are 55.04% chloride, 30.61% sodium, 7.68% sulfate, 3.69% magnesium, 1.16% calcium, potassium (1.10%) and the rest (less than 1%) consists of bicarbonate, bromide, boric acid, strontium, and fluoride. The causes of subsurface ocean currents you must know.

Natural seawater is saline water with a salt content of around 3.5%. Some salt lakes on land and some oceans have a higher salinity than most seawater. For example, the Dead Sea has a salt content of around 30%. Although most seawater in the world has a salt content of around 3.5%, seawater also varies in salt content.

The most unsatisfactory ones are in the eastern Gulf of Finland and in the north of the Gulf of Bothnia, both parts of the Baltic Sea. The salty one is in the Red Sea, where high temperatures and limited circulation make high evaporation and little input of water from rivers.

Thus the explanation of the level of salinity in the ocean. Hopefully, it can be a recommendation for new knowledge for you about marine.

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