How much salt water is on earth?

In this brief article, we are going to answer the question “how much salt water is on earth?”. We will also discuss whether or not humans can drink it and what are the risks of drinking it. In the end, we will discuss how to desalinate salt water.

How much salt water is on earth?

Over 97 percent of the Earth’s water is found in the oceans as salt water, and only about 2.5 percent of the water on Earth is freshwater. 

Most of the Earth’s water is salty seawater, with freshwater making up less than 1% of the planet’s total water.

The saline water has an average salinity of 35% (or 3.5%, or 34 grams of salts per kilogram of seawater), though this varies slightly based on drainage from adjacent land.

Almost 97% of Earth’s water originates from oceans, marginal seas, saline aquifers, and saltwater closed lakes, however no closed lake stores a geographically substantial amount.

The remaining water on Earth is the planet’s freshwater reserve. Fresh water has a salinity below 0.35 or 1% of the seas. .

On Earth, salt water is 50 times more abundant than fresh water. The distribution of fresh water in the world is also highly uneven. The vast majority of freshwater resides as ice, glaciers, aquifers, and soil moisture; barely 0.3% is liquid at the surface.

Lakes contain 87 percent of the liquid fresh surface water, wetlands include 11 percent, and rivers contain only 2 percent of the total surface water. In addition, little quantities of water exist in the air and living beings.

Freshwater resources, such as rainwater that flows into streams, rivers, lakes, and groundwater, provide humans with the water they need to survive every day.  However, the unseen water beneath our feet is also vital to life. 

Humans are pleased with this development because we utilize both types of water. Although surface water is utilized more for supplying drinking water and irrigating crops, groundwater is essential because it not only helps to maintain rivers and lakes full but also provides water to locations where surface water is rare, such as desert communities.

Can humans drink salt water?

No, humans can’t drink water as it is fatal to human life.

Salt is found in seawater. When humans consume seawater, their cells ingest both water and salt. Although it is acceptable for humans to consume tiny amounts of salt, the salt concentration in saltwater exceeds what the human body can handle.

 In addition to consuming salt as part of our everyday diets, we also consume liquids, diluting the salt and maintaining a healthy level.

 Living cells depend on sodium chloride (salt) to sustain chemical balances and reactions within the body; yet, an excess of sodium can be fatal. It also affects the human brain.

The urine produced by human kidneys is always less salty than salt water. You must urinate more water than you consume to eliminate extra salt from consuming seawater. You eventually expire from dehydration as your thirst increases.

What are the risks of drinking salt water?

On an empty stomach, drinking salt water may induce nausea and vomiting. Additionally, you may encounter cramping, bloating, and dehydration. The quick loss of salt and water during colon cleansing may result in metabolic acidosis.

This may result in:

  • Muscle spasms,
  • Weakness,
  • Dizziness,
  • Fatigue,
  • Dry-mouth,
  • Heart palpitations,
  •  Convulsions,
  •  Hypertension.

How to desalinate salt water?

Humans cannot consume saline water, but it can be converted into freshwater, which has a variety of applications. 

The procedure is known as “desalination,” and it is increasingly employed to give critical freshwater to people throughout the world.  

There are two fundamental ways of dissolving saltwater bonds: 

heat distillation and membrane separation.

Thermal distillation is dependent on heat. When water is heated to a boil, it evaporates into vapor, but the salt remains behind. This vapor can then be collected, cooled, and condensed back into the water.

The most popular method of membrane separation is known as reverse osmosis. By forcing seawater over a semipermeable membrane, salt is separated from the water.

In the simplest terms, water containing dissolved salt molecules is forced through a semipermeable membrane (basically a filter), where the bigger salt molecules are prevented from passing through the membrane holes while the smaller water molecules pass through.

Reverse osmosis is an excellent way for desalinating salty water, but it is more costly than other techniques.

Other FAQs about Salt that you may be interested in.

Does salt water taffy go bad?

Does sea salt expire?

How long do you smoke salt?


In this brief article, we answered the question “how much salt water is on earth?”. We also discussed whether or not humans can drink it and what are the risks of drinking it. In the end, we discussed how to desalinate salt water.


Was this helpful?

Thanks for your feedback!