Have you ever wondered how much water is on Earth? How much water is not on the surface, and how much of it is actually drinkable?
We’ll share these and similar facts about water with you below. Let’s dive in!
How Much Water is on Earth?
According to NASA, the percentage of land and water on Earth is approximately 25% and 75%, though some sources claim the percentage of water is closer to 71%. The total volume of the world’s water is 332.5 million cubic miles.
Throughout the years, the total mass of water doesn’t change. Still, the amount of available freshwater decreased, and currently, 1 in 10 people in the world lack drinkable water.
(USGS.gov, 2019, Water.org, 2021, NASA, 2010)
There are about 326 quintillion gallons of water in the world.
(USGS.gov, 2019, EarthHow, 2022, WaterServicesSite, 2022)
If you convert them to liters, you’ll get 1,233.91 quintillion. Interestingly, 96.64% of that water is concentrated in the seas, oceans, and bays.
On top of that, it’s interesting to know that the total amount of water on Earth stays the same at all times, only the form changes.
Only 3% of all water on Earth is fresh and drinkable.
(US Bureau of Reclamation, 2020, WorldBank, 2019)
Around 97% of the water on Earth is considered salty, while the drinkable and freshwater percent is only about 3%.
However, 79% of that freshwater is trapped inside glaciers and ice caps. Moreover, 20% of our freshwater is stored underground. This leaves us with less than 1% of accessible fresh water on Earth.
Despite this small number, 80% of the world’s wastewater is released back into the environment, further polluting the little freshwater we do have.
There are 321 million cubic miles of water in the world’s oceans.
(NOAA National Service Agency, 2021, Lisbdnet.2021)
According to NOAA, more than 70 percent of the Earth is covered by oceans. For illustration, only the Pacific Ocean covers more than 63 million square miles or more than 187 quintillion gallons of water.
There are four main theories about the formation of water on Earth.
(Harvard, 2021, Harvard, 2021, NOAA’s National Service, 2020)
The history of water is shrouded in mystery, and that’s why scientists developed 4 hypotheses — volcanic activities, extraplanetary sources, hydration of minerals, and planetary cooling.
One of them suggests that the water may have been here 3 to 4 billion years ago, and oceans, or more precisely, the world’s basin, formed approximately 3,8 billion years ago.
By 2025, almost 1.8 billion people will live in areas suffering from absolute freshwater scarcity.
(ScienceDaily, 2014, UNWater, 2018)
Additionally, scientists say that by 2040, the whole world will experience an extreme shortage of fresh water and water needed to produce energy.
The thing is, power plants need water for cooling and thus, are the biggest water consumers. So, if no changes are made, soon, there won’t be enough water for both consumption and electricity production.
There are 4 major water storages on Earth.
(Tutor2u.net, 2021, USGS.gov, 2018, USBR.gov, 2020)
The distribution of water on Earth happens in 4 main reservoirs:
- hydrosphere (the liquid water storage)
- atmosphere (the moisture storage)
- lithosphere (the bedrock storage)
- cryosphere (the ice water reserves)
What’s even more interesting is that 0.26% of Earth’s water is contained in us and other living organisms. So, for example, the eye is 95% water, and the whole body is approximately 75% water, the same percent as the Earth’s surface.
The water cycle consists of 5 major states, and it’s responsible for the different distribution of Earth’s water.
(Britannica, 2020, Britannica, 2020, UCAR, 2022)
The Earth’s water cycle goes through many phases, the most important of which are evaporation, transpiration, constipation, precipitation, and runoff.
Global warming disrupts and speeds up some phases of the cycle. This can cause coastal regions to become wetter, while the middle continental regions might become much drier.
Unfortunately, despite the water being the basis of all life, many people today take it for granted.
So, if you’ve ever asked yourself how much water is on Earth, we hope the answers above have given you a much clearer picture of the importance of preserving freshwater.
- Britannica, 2020
- Britannica, 2020
- EarthHow, 2022
- Harvard, 2021
- Harvard, 2021
- NASA, 2010
- NOAA National Service Agency, 2021
- NOAA’s National Service, 2020
- ScienceDaily, 2021
- Tutor2u.net, 202
- UCAR, 2022
- UNWater, 2018
- US Bureau of Reclamation, 2020
- USBR.gov, 2020
- USGS.gov, 2018
- USGS.gov, 2019
- WaterServicesSite, 2022How Much Water Is on Earth