What are the main factors influencing ocean salinity?

Ocean salinity, the concentration of salts in seawater, is influenced by several key factors:

Evaporation

Evaporation is a significant factor contributing to ocean salinity. When water evaporates from the ocean surface, it leaves the salt behind, increasing the overall salt concentration in the remaining seawater.

Precipitation

Precipitation plays a role in reducing ocean salinity. When it rains, freshwater from precipitation dilutes the saltwater in the ocean, decreasing its overall salinity level.

River input

River input introduces freshwater into the oceans, which can lower salinity levels in coastal areas where rivers flow into the sea. This freshwater carries lower salt content compared to seawater.

Sea ice formation

During sea ice formation, salt is expelled into the surrounding seawater, increasing its salinity. This process is crucial in polar regions where sea ice plays a significant role in regulating ocean salinity.

These factors interact to create the complex patterns of ocean salinity observed worldwide. Understanding ocean salinity is essential for studying marine ecosystems, the water cycle, and oceanography. Changes in ocean salinity due to factors like climate change can have profound impacts on marine life and global climate systems, making it a critical area of study in environmental science.