Today we are going to talk about Salinity in ocean water. Rocks on land are known to be the main source of salt dissolved in seawater. When rainwater falls on the ground it is slightly acidic and causes it to erode the rocks. And rocks release ions that are carried in streams and rivers that eventually feed into the ocean. Many of these dissolved ions are used by marine organisms and their concentration increases over time as they move away from the water.
The salt in our oceans comes from two main sources and such as flowing from the land and being exposed to the coast. Another source of salt in the ocean is the hydrothermal fluid, which comes from coastal vents. When ocean water enters the coastal cracks, it is heated by magma from the main part of the earth and that heat causes a series of chemical reactions.
The concentration of salt in seawater varies with time with temperature, evaporation and precipitation. The salinity in the ocean is usually lower at the equator and at the poles. It’s also high at mid-latitudes. The average salinity rate in the ocean is about 35 parts per thousand. And about 3.5% of seawater's weight comes from dissolved salt.
Places Of Lower Salinity In Ocean Water
Some parts of the oceans receive heavy rainfall. And that rain mixes seawater with freshwater added to the surface of the ocean causing a decrease in salinity. Antarctica has salinity just below 34ppt around the ocean. And locations around the Arctic Ocean are below 30ppt. Icebergs on such oceans break up ice sheets formed on land and contain no salt resulting in more salt being removed by cooling seawater in the bottom of the ice.
Places Of Higher Salinity In Ocean Water
Let me tell you that there are some parts of the ocean where there is very little rainfall and because of that hot dry winds in the oceans cause a lot of evaporation. This evaporation removes freshwater and when water vapor rises in the atmosphere it leaves the salt behind and this increases the salinity of the sea water. And the rain is not too much. In addition, the Mediterranean waters in Europe are very saline.
Variation In Salinity On Ocean Water
The salinity of ocean water varies from place to place. The salinity of most oceans in the world is between 34 ppt and 36 ppt.
What Happens When Salinity Changes In Ocean Water
The difference between 34 ppt and 36 ppt salinity is sufficient to know the salinity of seawater and to differentiate its density. Slightly moist ocean water also sinks under less dense water. So when the freshwater in the ocean cools, the effect is greater because the salinity temperature has a greater effect on the density. The combination of high salinity and low salinity temperature makes the sea water so dense that it sinks to the bottom of the ocean and a deep no and slow flow flows from the sea shore.
In earlier times the global understanding of sea surface salinity was very difficult as sampling by ships, bays, drifters and moorings was extremely limited at sea. The challenge in the world's oceans was to systematically measure the salinity, temperature and density of its water during the 1870s by H.M.S morning scientists. Techniques to measure such properties of seawater have long changed dramatically in method and accuracy.
Launched on June 10, 2011, the Aquarius on the Argentine spacecraft Aquarius is NASA's first satellite device specifically designed to study the saltwater content of surface water. The salinity variability of sea water is one of the main drivers of ocean circulation and is closely linked to freshwater cycling around the planet.
The salinity sensor invented by NASA detects microwave emissivity of 1 to 2 centimeters above sea level. And that sensor is a physical property that varies depending on temperature and salt. This type of instrument collects data every seven days in a 386 km-wide orbit designed for a complete survey of global salinity of ice-free seas.