Why Is The Ocean Water Salty?

Water covers 70 percent of our planet’s surface. Out of this percentage, oceans are bodies of water that are most prominent and get a larger chunk out of that number. Yet, only 3 percent is potent and drinkable to every living creature, including us humans. Ninety-seven percent are saline but home to the most organism that thrives underwater. Unfortunately, the salinity doesn’t make it drinkable.

It’s just that how does this happen? Why are rivers that flow and meet the open sea not? Why is the ocean water salty? There are still more questions but lesser answers. That is the mystery of mother nature. But still, luckily for us, we have the answer to the last question based on the research and findings to seek the truth. Here’s how ocean water became the biggest and saltiest body of water.

It starts with the precipitation, the water cycle

As you know, one of the reasons why the ocean water is salty is because of the rain. But do you know how rain is created? To make us understand further, let’s discuss the water cycle first. 

The water cycle of the earth has 3 phases, evaporation, condensation, and precipitation. It starts first with the evaporation process, where the liquid’s surface is turned into a gas. Next, the water from the rivers, lakes, streams, etc., are turned into water vapor that is then transported to the hydrosphere. 

Next is the condensation process, where the gases collected from the surface are turned into liquid. As the water vapor cools down, it reaches the saturation limit of its dew point before continuing to the last phase. This point is heavily influenced by the air pressure that depends on how heavy the dew point in an area is.

Lastly is the precipitation. This is the part where solid or liquid water droplets are released in an area due to the earth’s condensation in the atmosphere. Thus, precipitation includes the rain, hail, or snow under this phase, continuing the cycle.

Soil erosion from the rain

Since the rain is released into the atmosphere, it brings a little bit of acidity to it. Now, this acidity makes the soil in the land erode, bringing some parts to the bodies of water, especially the rivers, and now to the open sea.   

The rain is slightly acidic due to the carbonic acid that is mixed with the liquid. This is from the carbon dioxide in the atmosphere dissolved in the air combined with the rain. Now, when they hit the ground and cause slight erosion of the soil, the water is mixed with the ions and minerals from the ground. 

So, these ions and minerals flowing from the river and streams are now washing to the open sea, leaving the latter the basin for the sediments collected. Then, the creatures within use these dissolved ions, although not all are contained in the water. The leftover runoffs increase over time; that’s why oceans are getting saltier.

Also, from vents in the sea floor

Another reason why the ocean water is salty is from the hydrothermal fluids released from the vents in the seafloor. They are recently discovered features peaks of oceanic ridges that contribute to the dissolved minerals released to the ocean.

Here, ocean water bleeds into the floor cracks and is heated by the earth’s core’s magma. Then, this heat causes a series of chemical reactions in the process. Thus, when the heated water is released through the vents, metals, minerals, and ions come with it.

Volcanic eruptions

As you would have known, there are also volcanoes underwater. Precisely, of course, some of them are active while some are dormant. So, like the volcanoes up in the land surface, they also have eruptions underneath. 

These very active volcanoes beneath the sea surface release magma into the ocean and its floor. Thus, these phenomena, just like the vents, release minerals directly and openly. As a result, the deposits are infused with magma discharges that indeed affect the salinity level of water. 

The salt domes

An additional answer to why the ocean water is salty is because of the salt domes. They are formed due to the underground salt’s buoyancy when mixed with other sediments on the ocean floor. Afterward, these combinations float upward to form domes, sheets, pillars, and other structures made of salt.

So, these formations largely contribute to the ocean’s saltiness levels. As an added knowledge, these domes form over geological timescales that can be found under the sea and underground around the world. For example, they can be found and are shared across the continental shelf of the northwestern part of the Gulf of Mexico.

The balance

Despite knowing that the sea and ocean are salty, their saltiness is not actually in uniformity. According to the discussion earlier, the ions and minerals deposited in the ocean and sea are being removed by animals and algae living there. Also, they are being deposited as sediments at the bottom of the ocean floor. So, the remaining salt is fused with the ocean itself.

Also, you should never forget that it is only natural that all seas and oceans do not have the same salinity. Places with warmer climates have saltier waters because evaporation occurs more in these areas than in the colder ones. So, the hotter the area, the more the water cycle repeats in a short period, the more minerals and ions are received.

Conclusion

We hope that you have learned something from this article. If ever you already knew this from before, we hope that your memory is refreshed on why the ocean water is salty. You should also remember that with climate change getting more evident as the years go by, the saline level and the density will change, especially in the future.

Here at ATOLEA, we are focused on giving back to the Ocean. Part of our profit from your purchase on our Ocean-inspired jewelry goes to Ocean conservation charities. 

So check out our Sea-inspired jewelry now and wear your love of the Ocean!