óceánvíz

Óceánvíz refers to the saltwater that makes up the Earth's oceans. It covers approximately 71% of the planet's surface and is a critical component of the Earth's climate system. The composition of óceánvíz is primarily water (H2O), but it also contains dissolved salts, gases, and organic matter. The most abundant dissolved salt is sodium chloride, commonly known as table salt. Other significant ions include magnesium, sulfate, calcium, and potassium. The salinity of óceánvíz, which is the total amount of dissolved salts, varies geographically but averages around 35 parts per thousand (ppt).

Ocean currents, driven by a combination of wind, temperature, and salinity differences, distribute heat and nutrients globally, influencing weather patterns and supporting marine ecosystems. The oceans are home to an immense diversity of life, from microscopic plankton to the largest whales, forming complex food webs. Óceánvíz plays a vital role in the carbon cycle, absorbing and storing significant amounts of atmospheric carbon dioxide. It is also a source of resources for humans, including food, minerals, and energy, and serves as a major transportation route. The health of óceánvíz is increasingly a concern due to issues like pollution, overfishing, and climate change, which lead to phenomena such as ocean acidification and sea-level rise.