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𝔴𝔢𝔟 𝔩𝔬𝔤


Its unique properties

There are a number of qualities that set seawater apart from fresh water. Seawater is more dense than fresh water, and it also has higher salinity and a slightly alkaline pH. (See page 8 of this document.)

The salinity of the ocean gives it some special properties - firstly, it is much more conductive than fresh water, with conductivity varying by region. The occurrence of salt in seawater also decreases its freezing point. Salt levels in the North Atlantic ocean cause polar water to freeze at about -1.8°C.
The shell of a pteropod dissolving over 45 days in a simulation of ocean conditions in the year 2100.

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When dissolved in water, CO2 becomes carbonic acid. Carbonic acid is a natural component of seawater, but increased carbon emissions due to industrialization have caused the levels of carbonic acid in seawater to increase significantly over time. The natural, alkaline pH of the ocean is something that marine life has adapted to over millions of years; as the pH decreases, ocean conditions become increasingly hostile to marine organisms that are not adapted to survive them. In one laboratory trial simulating the projected ocean conditions in the year 2100, the shell of a pteropod (a small marine mollusc) dissolved almost entirely over the course of 45 days. (See above)

While this sounds like quite a scary situation, there have been many solutions proposed to combat ocean acidification - for instance, the planting of seaweed. A group working in partnership with an oyster hatchery in California found that growing plots of native red seaweed helped to moderate carbon and nitrogen levels in the local area.