merisuolapitoisuus

Merisuolapitoisuus, or salinity, refers to the concentration of dissolved salts in seawater. It is typically measured in parts per thousand (ppt) or practical salinity units (psu). The average salinity of the world's oceans is about 35 ppt, meaning that for every kilogram of seawater, there are approximately 35 grams of dissolved salts.

The primary components of sea salt are sodium chloride (NaCl), but other ions such as sulfate, magnesium, calcium, and potassium are also present in significant amounts. Salinity is not uniform across the globe. It varies due to factors like evaporation, precipitation, riverine input, and the melting of ice. Higher evaporation rates, such as in subtropical regions, lead to increased salinity, while areas with high rainfall or significant freshwater inflow from rivers tend to have lower salinity.

Salinity plays a crucial role in oceanographic processes. It affects seawater density, which in turn drives ocean currents through thermohaline circulation. Higher salinity leads to denser water, causing it to sink. This density difference is a fundamental driver of the global ocean conveyor belt, influencing heat distribution and climate patterns worldwide. Additionally, marine organisms are adapted to specific salinity ranges, and changes in salinity can significantly impact marine ecosystems and biodiversity. Scientific measurements of salinity are essential for understanding ocean health and climate change.