How Has the Earth’s Entire Water Supply Not Already Been Exhausted?

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There are currently about 7 billion people on the planet, all of which require water to survive. Even without the direct consumption of water, water is usually in most other beverages that people consume. Also, many of these billions of humans use massive amounts of water everyday to do laundry, bathe, wash dishes, and so forth. Many animals require water to survive as well.

Also, humans and animals requiring frequent water consumption has been a thing for billions of years. Obviosuly Earth’s water supply is not infinite. How have we not already exhausted all the water the Earth has to offer?

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7 Answers

Anonymous 0 Comments

A water cycle exists in which water evaporates from lakes, rivers, and oceans, but the water vapor in the atmosphere eventually condenses and falls as precipitation. This is constant, so there is always water flowing in rivers and lakes have relatively stable levels. Consumption of water by organisms is temporary, and water leaves the body by peeing, sweat, and vapor during respiration. So its residence inside organisms is temporary, and it eventually goes back into the water cycle. There are a few cases where humans have exhausted local water supplies, but the cycle is global.

Anonymous 0 Comments

You all are right, of course, but have missed perhaps a more convincing direction for explanation: We are small and the earth is big.

There is a lot of water in earth. See. https://science.howstuffworks.com/environmental/earth/geophysics/question157.htm, where the estimate is 326,000,000,000,000,000,000 gallons, (multiply by four for liters – 1.3 times 10 to the 21 liters. Dividing by the US figure of 1,200 kL per year one gets an extremely low calculation of approximately 1 times 10 to the 15 or 1,000,000,000,000,000 people-years of water.

Dividing this by the 7 billion people in the world figure, used already, one gets a bit over 10 billion years. So, it would take the current 7 billion people in the world about 10 billion years to consume the water in the world.

If one assumed that perhaps 100 billion people have been born, most died as infants, but perhaps having an average lifespan of 20 years, one still has humans consuming 1/5,000,000 of the water on the earth, unless I missed something.

Note, again, this calculation assumed the highest current water consumption for the entire world and over all time – a extremely gross overstatement.

Bottom line, even if water disappeared when people or people’s technology used water, we are insignificant, compared to the volume of water on earth.

Anonymous 0 Comments

Fantastic question. I love the logical reasoning in your question.

TLDR: (i) Not all countries consume water by the standards of handful of developed nations. (ii) The situation of fresh potable water consumption is dire. But not all consumption is of fresh water.

If one looked at only the consumption in the developed nations and project it on all of humanity, your question shall be valid. However, such projection shall be done with caution if not avoided entirely. Water is like electricity when it comes to consumption by countries based on the economic prosperity. People in developed countries consume a lot of water per person because higher standard of living is resource -expensive. By consuming water, I mean for all purposes including bathing, washing, etc. People in less developed nations need less. As fate would have it, there are fewer developed nations than less-developed nations. Further, the population in developed nations is significantly less than in less-developed nations. The combined effect is that a large population needs less water, and a very small population needs a lot of water.

Within the developed nations as well, the consumption of water differs widely. In America, the consumption is around 1200 Kilo-litres per annum per person, which is much more than the second highest consumption of 800 kilo-litres for Canada. Compare that with 400 for France or 140 for Israel.

Here is further motley reasons, not in any particular order that might help you understand the situation.

1. Not all humans have access to clean water. A very large portion of those 7 billion that you speak of consume less than clean water.

2. Not all humans consume water by the standards of developed nations. Doing the dishes, washing clothes etc are done on the ponds in villages in a large number of countries. This water is often not fit for drinking by the developed countries standards. Washing and bathing in water fit for drinking is a luxury for a large population.

3. The number of showers per week, the number of dishes to be done, the number of clothes to be done per week (and how, ie manually or by machine) differ significantly across countries and within society as well.

4. Not all consumption of water is through pure liquid water. We get a lot of our water from fruits, vegetables and other food items.

Anonymous 0 Comments

when you use water, you don’t make it ‘not water’. think of all the things you do with water.

you drink it, but at same time, you sweat it and you pee it. 1 water goes in, 1 water comes out.

you wash your clothes and dishes with it. 1 water goes in, 1 water comes out.

the big one that makes water into not water is growing plants/crops. plants take CO2 and water and split it apart in photosynthesis to make glucose (sugar) and oxygen and a little water out. 2 waters in, 1 water out. it’s a good thing that when we digest crops as food sugars, we take 1 glucose and oxygen and get CO2 and water and energy as output. completing the cycle

Anonymous 0 Comments

Matter is conserved. All the water we drink eventually is breathed out, peed out, or otherwise re-enters the environment, such as if you die and are either buried or cremated.

It’s possible to split water into oxygen and hydrogen by electrolysis, but this takes a huge amount of energy and organisms don’t do this naturally. Oxygen and hydrogen of course can be turned back into water, but since hydrogen is so light it rises up and some of it is lost to outer space.

This doesn’t destroy it for good (matter is still conserved), but it would make it very difficult to undo.

Anonymous 0 Comments

There is a water cycle. In the wild, waste water from urine or other bodily fluids can evaporate and come back down as rain. In developed countries, waste water goes into a treatment plant or septic tank before evaporating or being dumped into rivers. In developing countries, waste water may go directly into rivers or be treated in some other way. But all water we usr comes back out in some form or another, where it eventually evaporates and comes back down as rain.

Anonymous 0 Comments

We’re really good at recycling used water. And rains and river flows help fill up dams.

So eventually you do end up drinking toilet water.

(Sleep tight)😂