Why is the Ocean Salty?
The saltiness of the ocean comes from a lot of factors. We can outline these factors. We can first discuss the water cycle.
Solar energy evaporates water from the ocean, lakes and rivers. This evaporates and takes the form of gas. This is also called water vapor.
These water droplets in the atmosphere is cooled and formed into clouds. This becomes heavier and falls into the Earth. This falls in the form of rain or snow.
Rain water contains traces of carbon dioxide from the air. This turns the water acidic. The rain water that falls will pass through mountains, rocks and sands. This rain water will erode the rocks and soils.
The erosion allows rain water to carry chemical and mineral salts. This is in the form of ions. It will carry into the streams, lakes and rivers.
Some ions are used by organisms living in these smaller bodies of water. Other ions are kept for long periods of time to accumulate.
These waters eventually flows back into the greater or larger bodies of water; the oceans and seas. These oceans and seas tend to receive more ions because they are bigger and larger. These ions are come from overflows of smaller bodies of water. They are also carried from solid and gaseous elements. An example would be volcanoes or volcanic vents.
Suspended particles are swept into the ocean by winds. Materials dissolved from sediments deposited on the ocean floor also contribute to these factors.
The salt dissolved in the sea is left behind as the water from the ocean evaporates again. Only freshwater is evaporated into the atmosphere because salt is too heavy. The cycle goes on.
Some salt in the seas deposited into the ocean floor are sediments. The level of salt left in the seas is greater than the consumption. This would be the reason the seas become increasingly saline over time.