Could the ocean ever become too salty for life to exist?
It may taste good on crisps, but too much sea salt can be harmful to fish and plants.
Asked by: Martin Simpson, Huddersfield
In the open ocean, whatever water evaporates must eventually return. Rivers continually wash more salt in from the land, but the sea has reached equilibrium now, and extra salt just precipitates out of solution onto the ocean floor.
The concentration of salt in the Dead Sea is almost 10 times higher than the average for the rest of the oceans. This is far too salty for fish and plants, but even here there are some bacteria and fungi that can survive. The Dead Sea’s high salinity is because the water is evaporating much faster than fresh water flows in.
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Authors
Luis trained as a zoologist, but now works as a science and technology educator. In his spare time he builds 3D-printed robots, in the hope that he will be spared when the revolution inevitably comes.
