What can salinity decrease from?

What can salinity decrease from?

Evaporation of ocean water and formation of sea ice both increase the salinity of the ocean. However these “salinity raising” factors are continually counterbalanced by processes that decrease salinity such as the continuous input of fresh water from rivers, precipitation of rain and snow, and melting of ice.

What are 2 ways you can decrease the salinity of the ocean?

rain, snow, melting ice, and fresh water from rivers lower the salinity of ocean water. Evaporation and the freezing of surface water increase salinity.

What causes low salinity in the oceans at high latitudes?

At high latitudes where sea ice forms seasonally and icebergs are often released into the open ocean, the salinity of the seawater is reduced when ice melts and is elevated during ice formation. This saltier water can then sink down into the deep ocean (see density current).

How can we reduce salinity in water?

Remember that excessive salinity (seawater or brackish water) can only be reduced by using the reverse osmosis or electro dialysis membrane techniques (see chapter separation by membranes) or by distillation (see chapter degasification, odour control, evaporation).

How can we prevent salinity?

Treatment

1. avoiding over-irrigation by monitoring soil moisture to work out water requirements.
2. good crop selection such as using deep-rooted plants to maximise water extraction.
3. minimising fallow periods using crop rotations and break crops.
4. avoiding deep ripping and overtillage to minimise infiltration of water.

What are factors affecting salinity of seawater?

Salinity of seawater is affected by evaporation, precipitation, ice formation, and ice melting. Evaporation increases the salinity of seawater because when seawater evaporates, the salts are left behind, thus increasing their concentration.

Does the decrease in salinity near the equator cause an increase or decrease in density?

Near the equator, the tropics receive the most rain on a consistent basis. As a result, the fresh water falling into the ocean helps decrease the salinity of the surface water in that region. As the temperature decreases to 40 °F (4 °C ) the molecules slow, water contracts and the density increases.

How do salinity vary with depth in the ocean?

Typically, the salinity decreases from the surface ocean to deep waters is very small, from about 36 g/L (ppt) at the surface to 35 g/L (ppt) in the deep water, thus there is a very small density decrease with depth given a constant temperature. The salinity of seawater also affects it’s freezing point temperature.

Is there a way to remove salt from seawater?

There are several ways to remove salt from water. Reverse osmosis and distillation are the most common ways to desalinate water. Reverse osmosis water treatment pushes water through small filters leaving salt behind. Distillation on a large scale involves boiling water and collecting water vapor during the process.

How does the salinity of the ocean affect ocean circulation?

Deep below the surface, however, ocean circulation is primarily driven by changes in seawater density, which is determined by salinity and temperature. In some regions such as the North Atlantic near Greenland, cooled high-salinity surface waters can become dense enough to sink to great depths.

Where is the lowest salinity in the ocean?

The ocean around Antarctica has a low salinity of just below 34ppt, and around the Arctic it is down to 30ppt in places. Thawing icebergs add freshwater – icebergs that have broken off ice sheets formed over land do not contain salt, and the freezing of seawater into ice floes removes more salt. The Baltic Sea,…

What is the salinity of the Mediterranean Sea?

The Mediterranean Sea in Europe has very high salinity – 38 ppt or more. It is almost closed from the main ocean, and there is more evaporation than there is rain or extra freshwater added from rivers.

How does weathering affect the salinity of the ocean?

The weathering of rocks delivers minerals, including salt, into the ocean. Evaporation of ocean water and formation of sea ice both increase the salinity of the ocean.