Are these estimates for average water usage correct?

[PB666]

I thought I would share this link with the group.

They claim that average water use per annum is 10700 cu kilometers. This sounds insanely high.

http://www.bbc.com/news/science-environment-35082422

I calculated this is equal to

1.07E13 cubic meters of water of 1.07E16 liters of water per year, per person this comes out to 1.5E6 liters per year or 4185 liters per day.

10700 = 1.07E4

A kilometer = 1000 (10^3) meters. A cubic kilometer is therefore 10^9 meters cubed. 10700 x 10^9 = 1.07E13. There are 1000 liters in a cubic meter so this translates to 1.07E16.

1.07E16 / 7E9 = 1.5E6. 1.5E6/365.25 = 4185.

So here I worrying about a 40 gallons water use a day, why exactly am I worrying, the water use that is out of my control exceeds the water use under my control by a factor of 20.

A single pound of beef takes 1800 gallons of water. Hmm since I don't eat beef, not a problem. Ok so I do eat buffalo (very little of it in fact, but I only eat small amounts of grass feed animals) but its forbidden here to feed them cultured crops so  . . . . .

http://www.gracelinks.org/1361/the-water-footprint-of-food

Here is a table: http://www.theguardian.com/news/datablog/2013/jan/10/how-much-water-food-production-waste

1 kilogram of rice needs 2500 liters of water, if we consider the energy by density that is about 10000 liters per gallon of cooking oil, if the oil was made from converted starch with no loss of energy during the transition, that about 0.8kg of fat on the body. 

Egg is a pretty good choice, its 196 liters of water. (57-60 grams per egg) = 3333 liters per kg of eggs. Better choice than beef, which is 15000 liters per kg. Better than chicken, pork, lamb  at 4333 per kg, 6000, 10000, respectively, liters of water used per kilo.

The worst choice is chocolate, its apparently 17000 liters per pound, its largely fat, so its about twice as water hoggy as rice.

Banana and potatoes are a better choice, but their water content is higher than rice.

Corn, uses 147 gallons (558.6 liters) per lb of corn, a lb is 0.45 kg so thats 1228.9 liters (compares to 1600 for wheat, barley and rye). Woohoo I score on this one, I eat lots of maize. Dried beans, another native american food crop is 2200 liters per dried kilogram. A quarter cup contains as much protein as an egg, though I think beans and corn both need supplimental sources, so that egg is still in the water budget.

None the less I still don't see where the 4185 liters/day is coming from, at least.

So this post is tangentially important here, lets say we cut this down to say 800 liters of water a day, this means for every person living in a mars colony if the food is sustainably grown, they are going to have to have something like 100 day supply of water for the crops they grow even if water is perfectly recycled, this means for every person they are going to need to find 80000 liters of water and a place to store maybe 30 percent (because water use shifts in the life of a crop). Things like having water for bathing is a triviality, The greenhouse where the crops are grown would need to be perfectly sealed, even from the bottom, a loss of 1% of the daily water need per day translates into 8 liters of water a day, if there are a dozen people in the colony you would need 100 liters of water generation per day just to keep up. This means something else, structures capable of retaining water (sill-plastic) will need to be brought from earth even if the materials to construct the rest of the greenhouse can be made on mars (aluminum, glass).In addition, prolly gonna needs some chickens, though the budge may not be as bad, since some of the crop waste can be used to feed chickens (ive even heard they eat waste from other animals, humans?). And pretty much if you raise chickens you cant tell the sex till there a certain age so at least some of the males and older females will be on the menu. That entails bringing chickens from earth to mars, you can incubate eggs part of the way, but at some point you are going to have little chicks floating around in space.

 

 

 

 

 

Edited December 17, 2015 by PB666

[YNM]

The figure is correct. As they also accounted for evapotranspiration in human realms (fields, artificial lake, canal, salt pan, anything), of course the number increases quite significantly. You don't get waste water from them though - you get water vapor. Anyway, what we need to also know is what's the effect of "overvolting" the natural water mechanism (which one intermediate step involves evaporation and condensation, then precipitation) because that's essentially the result of the phenomenon in the study you pointed out.

[micr0wave]

1 liter of table water needs 1.5 liters water

[PB666]

9 hours ago, YNM said:

The figure is correct. As they also accounted for evapotranspiration in human realms (fields, artificial lake, canal, salt pan, anything), of course the number increases quite significantly. You don't get waste water from them though - you get water vapor. Anyway, what we need to also know is what's the effect of "overvolting" the natural water mechanism (which one intermediate step involves evaporation and condensation, then precipitation) because that's essentially the result of the phenomenon in the study you pointed out.

By overvolting you mean alteration of local climates and hydrology as a result of increased transpiration. 

Two effects, first particulate emmision, notably coal smoke and chaff burning are going to lower pan evaporation rates, so rises in transpiration in asia due to rice farming may be offset by these particulate emmisions. 

The second is jet trails, these high altitude trails were once believed to block evaporation rates, however its now observed that over forest the diffuse light they produce allows photosynthesis deeper into the canopy for longer periods, since the upper leaves saturate with light, at the saturation limit transpiration begins to be modulated, howver the light that is redistributed by jet trails is permissive to more transpiration. 

The other metric is lakes for water storage versus oceans, fresh water has a higher evaporation rate. Much of that water is returned locally in the form of precipitation. Overuse for agriculture reduces and changes the pattern of soil hydration, droughts caused by climate change also alter this.  

Lakes Mead and Chad are examples of drought caused lowering, the aral sea is an example of overuse. In the case of greenland warming results in freshwater basins in the summer time. 

In a greenhouse i assume that the LED lighting system would be tuned to the exact frequency plants need and pulsed as to prevent photosynthetic saturation, thus minimizing the amount of transpiration. However plants grow bigger faster, low protein crops lose their advantage for things like C4 (corn), so then the specialization would be into things like legumes. Quinoa is somewhat advantageous because its high altitude growth means the greenhouse pressure can be lowered, other high altitude crops may be selected.

 

 

9 hours ago, micr0wave said:

1 liter of table water needs 1.5 liters water

Dont drink water at the table, lol.

[AngelLestat]

You can not guide based on those numbers. Because the water footprint statistics are intended to provide strategy information on what kind of entrepreneurship is advisable for a certain location.

This is the thing I have against some green advocates, they use those numbers (to scare or impress people) which are not designed to reflect real water consumption, then people believes that it does not matter to leave the tap open because if they eat a single beef will be much worst.

But that is not true, the only water consumption that you need to be worry, is the one you extract from the aquifers and does not go back (or go back with a big amount of pollutants). But the water footprint also counts rain water or other cycles (which in fact refill the aquifers), they also count all the water that needs to fall to the ground, so a small % of that is absorbed by the grass, then a % of that is absorbed by the cow (they dont count the water that returns to the ground by evaporation or by pee), and then, they use the same system to calculate transport and all process until it reach your table.

 

 

 

[YNM]

2 hours ago, PB666 said:

By overvolting you mean alteration of local climates and hydrology as a result of increased transpiration. 

Two effects, first particulate emmision...

The second is jet trails...

Hmm, are those jokes ? Hopefully they are.

17 minutes ago, AngelLestat said:

You can not guide based on those numbers. Because the water footprint statistics are intended to provide strategy information on what kind of entrepreneurship is advisable for a certain location.

...the only water consumption that you need to be worry, is the one you extract from the aquifers and does not go back (or go back with a big amount of pollutants).

Fully agree with you here. What matters is the pollution we create - water cycle are, AFAIK, a fully returning cycle (unless you count in very deep aquifer waters, which is really hard to return; What would you do to return water into the mantle, dropping water bombs into volcanoes ?), and the only thing we're really messing with it is the pollution level (not just sand, silt and clay anymore). Although, for aquifers, one have to admit that too much of them (pumps) and basically you're cavitating the ground below you. (pumps are more or less "vacuum" ?)

Edited December 18, 2015 by YNM

[PB666]

1 hour ago, AngelLestat said:

You can not guide based on those numbers. Because the water footprint statistics are intended to provide strategy information on what kind of entrepreneurship is advisable for a certain location.

This is the thing I have against some green advocates, they use those numbers (to scare or impress people) which are not designed to reflect real water consumption, then people believes that it does not matter to leave the tap open because if they eat a single beef will be much worst.

But that is not true, the only water consumption that you need to be worry, is the one you extract from the aquifers and does not go back (or go back with a big amount of pollutants). But the water footprint also counts rain water or other cycles (which in fact refill the aquifers), they also count all the water that needs to fall to the ground, so a small % of that is absorbed by the grass, then a % of that is absorbed by the cow (they dont count the water that returns to the ground by evaporation or by pee), and then, they use the same system to calculate transport and all process until it reach your table.

 

 

 

(Note: I tried to respond to this on my handheld once again complete failure).

I will give you an example. Lets take Medina lake which straddles the Edwards aquifer, the dam is owned by the local farming communities but the aquifer serves San Antonio. Water released from the dam is split and fed by irrigation canals where is used to grow corn and other vegetables, some of that is used to grow alfalfa and maize which is used to feed cattle, during a severe drought the dam can be closed and all the water goes into feed the aquifer. If the aquifer is high enough it feeds several streams as it used to, if it is low enough it will stop feeding the San Antonio river, which essentially becomes a treatment plant outlet. The spring feeds the San Antonio river provides water for Brakenbridge park recreational area and the San Antonio river walk, the park dry-out rarely or never happens.

IOW its not like you think, in a severe drought if the irrigation is blocked then the aquifer automatically fills these recreational areas, which is close to its natural water level in many areas , if the lake is emptied then water to recreational will stop without any human decisions to make, some area parks may spring water that has not produced in decades. If the lake is completely drained, then the cows, pigs, and chickens get the water along with crops for humans. Either way humans consume the water since it is difficult to separate natural from recreational. Very little of the water of the original Upper Medina river actually junctions with the San Antonio river south of San Antonio, except during severe floods water enters a decision loop. The same can be said of the Rio Grande river, if the US chooses to ration its use, Mexico will take what the US does not. The same can be said about the Western US's Colorado river.

1 hour ago, YNM said:

Hmm, are those jokes ? Hopefully they are.

 

Since it was difficult to understand your original point Im glad you find humour in it. Climate change is not just about global warming, there are many effects that humans have on climate, as the other threads have clearly pointed out with graphs. What constitutes evaporation and transpiration differs from place to place and at different times as the climate change. Humans have major impacts on these activities, if you really want to see how tragic effects are, as the man said, go to Africa, the have bore alot of the cost of climate change, not only do they have to deal with higher temperatures, but sea surface evaporation, which determines inland rainfall is govern by direct sunlight that strikes the sea surface. This is blocked by particulates that come from India, as a consequence their climate is not only hotter but also dryer.

[magnemoe]

2 hours ago, YNM said:

Fully agree with you here. What matters is the pollution we create - water cycle are, AFAIK, a fully returning cycle (unless you count in very deep aquifer waters, which is really hard to return; What would you do to return water into the mantle, dropping water bombs into volcanoes ?), and the only thing we're really messing with it is the pollution level (not just sand, silt and clay anymore). Although, for aquifers, one have to admit that too much of them (pumps) and basically you're cavitating the ground below you. (pumps are more or less "vacuum" ?)

Yes, if you use too much ground water the ground level will sink, this is the case many places, Venezia is most famous. 
In the north sea they had to lengthen the legs of oil platforms as the sea bottom sank after removing oil.
Another issue by removing ground water close to the shore is that its an salt water layer below the fresh water layer and removing fresh water will push salt water up. 

[YNM]

11 hours ago, PB666 said:

Since it was difficult to understand your original point Im glad you find humour in it. Climate change is not just about global warming, there are many effects that humans have on climate, as the other threads have clearly pointed out with graphs. What constitutes evaporation and transpiration differs from place to place and at different times as the climate change. Humans have major impacts on these activities, if you really want to see how tragic effects are, as the man said, go to Africa, the have bore alot of the cost of climate change, not only do they have to deal with higher temperatures, but sea surface evaporation, which determines inland rainfall is govern by direct sunlight that strikes the sea surface. This is blocked by particulates that come from India, as a consequence their climate is not only hotter but also dryer.

Indian particulates ? Is this like the "you know, your land is fertile because of fine dust from foreign desert far away lands on top of your crops every day" ? If that's the case, it's not just hilarious, that's amazing. We should really study more of our own planet, not just sending probes to prospect oil / ores in foreign celestial bodies.

[PB666]

On December 17, 2015 at 6:40:02 PM, YNM said:

 

YMN, do you have a problem with thevidea that particulates block sunlight or lower pan evaporation rates. i notice your location, is this a defensive posture based on national policies?  Go look through the other threads, it is quite clear in those graphs that anthropogenic particle emmisions are resposible for a cooling component, NASA has already published images showing the visible pollution streams coming off India and Southeast Asia, not to mention that a hefty percent of the worlds most polluted cites are in India.  

Coal smokes, firest burns, and wood burning lower pane evaporation rates, tis a fact, deal with it. 

 

 

 

[YNM]

22 hours ago, PB666 said:

YMN, do you have a problem with the idea that particulates block sunlight or lower pan evaporation rates. i notice your location, is this a defensive posture based on national policies?  Go look through the other threads, it is quite clear in those graphs that anthropogenic particle emissions are responsible for a cooling component, NASA has already published images showing the visible pollution streams coming off India and Southeast Asia, not to mention that a hefty percent of the worlds most polluted cites are in India.  

Coal smokes, forest burns, and wood burning lower pane evaporation rates, tis a fact, deal with it. 

Hmm... So, forest fires particulate are no different than volcano eruption particulate (in terms of cooling or heating effect) ? That's new to me, to be honest. No, it doesn't have anything to do with the land I sit in or the bunch of heads sit few tens of kilometers from me, just it haven't struck me that way. By the way, the idea is, hmm... scary... Increase in CO2-caused IR albedo is slightly countered by increase in visual albedo by particulates. We should engineer plants that basically produce enough particulate to offset the CO2.

Edited December 20, 2015 by YNM

[PB666]

4 hours ago, YNM said:

Hmm... So, forest fires particulate are no different than volcano eruption particulate (in terms of cooling or heating effect) ? That's new to me, to be honest. No, it doesn't have anything to do with the land I sit in or the bunch of heads sit few tens of kilometers from me, just it haven't struck me that way. By the way, the idea is, hmm... scary... Increase in CO2-caused IR albedo is slightly countered by increase in visual albedo by particulates. We should engineer plants that basically produce enough particulate to offset the CO2.

As i said that is why they changed the whole pardigm to climate change, it very complex, some areas fir some periods have actually cooled. For example there is a pocket of the northbpacific that has cooled because the particulates from china trend toward the north pcaidic. In north america this has had tragic consequences because when the water sets warm around oceania and cold in the north pavific la nian predominates producing severe droughts as has been seen in the American west, the loss of ground water raises temperatures because of evaporative cooling. The general rule is that particulates above oceanic bodies of water are big drought priduces on land, lower temperatures of a particular local but raise temperatures on adjacent downwind masses of land. 

[cantab]

The original estimates seem plausible. Here on Earth most water usage is in agriculture and industry, very little comes from our taps at home. And even at home you use far more for cleaning and bathing than for drinking.

But water is a renewable resource. In space or on Mars you will be recycling it, so what you need is a water treatment plant that can keep up, not a giant tank. Also the industrial use as applied to a space/Mars colony will have been used to make and launch the spaceship in the first place.

As far as Earth goes, it's not the whole story either. An important question is how much of that water is purified drinking water, and how much is not. In many countries the problem isn't so much not having water as not being able to purify it.

[AngelLestat]

On 18/12/2015 at 11:36 AM, PB666 said:

I will give you an example. Lets take Medina lake which straddles the Edwards aquifer, the dam is owned by the local farming communities but the aquifer serves San Antonio. Water released from the dam is split and fed by irrigation canals where is used to grow corn and other vegetables, some of that is used to grow alfalfa and maize which is used to feed cattle, during a severe drought the dam can be closed and all the water goes into feed the aquifer. If the aquifer is high enough it feeds several streams as it used to, if it is low enough it will stop feeding the San Antonio river, which essentially becomes a treatment plant outlet. The spring feeds the San Antonio river provides water for Brakenbridge park recreational area and the San Antonio river walk, the park dry-out rarely or never happens.

IOW its not like you think, in a severe drought if the irrigation is blocked then the aquifer automatically fills these recreational areas, which is close to its natural water level in many areas , if the lake is emptied then water to recreational will stop without any human decisions to make, some area parks may spring water that has not produced in decades. If the lake is completely drained, then the cows, pigs, and chickens get the water along with crops for humans. Either way humans consume the water since it is difficult to separate natural from recreational. Very little of the water of the original Upper Medina river actually junctions with the San Antonio river south of San Antonio, except during severe floods water enters a decision loop. The same can be said of the Rio Grande river, if the US chooses to ration its use, Mexico will take what the US does not. The same can be said about the Western US's Colorado river.

I dont understand your main point with all this? Is like I said before, you just need to be worry of the water you extract from the aquifer and does not go back, or go back polluted. If you used as irrigation, a great part of that water goes back (in X years depending your aquifer deep).  Some other part is evaporated and increase a bit the raining in the zone. (That is why jungle places get so much raining, because they absorb almost all the water in the ground and evaporates that to repeat the cycle).

In some places ok you need to be worry if you extract a lot of that aquifer water than it will end in some other place.
 

 

[PB666]

8 hours ago, AngelLestat said:

I dont understand your main point with all this? Is like I said before, you just need to be worry of the water you extract from the aquifer and does not go back, or go back polluted. If you used as irrigation, a great part of that water goes back (in X years depending your aquifer deep).  Some other part is evaporated and increase a bit the raining in the zone. (That is why jungle places get so much raining, because they absorb almost all the water in the ground and evaporates that to repeat the cycle).

In some places ok you need to be worry if you extract a lot of that aquifer water than it will end in some other place.
 

 

It does not if it is used for agriculture below the recharge zone. What i am saying is that it complicated, in all but the most wet years all the water is allocated, if i chose not then someone else choses. 

[AngelLestat]

That is a weird case, is not the rule in the rest of the world.

And what is your solution?
Waste water before someone else waste it for you? It does not have much sense.

What I am saying is that never is good to waste water, that is something everybody should learn since childhood. Then when they grow up they design, think and act according to that. Then the amount of water save it is a lot.  

[PB666]

No but how can you argue to someone that they shouldn't water their potted plant whike you are eating a beef steak that uses a thousand gallons of water, people who live in the city pay 100 times more for water than agriculture does, and this then gies to feed cows a process that is water wasteful, carbon wasteful, environemtally damaging, and unless you are starving is generally an unhealthy product.  They should rally be telling any person to conserve water unless they are willing to go after the worst offenders first.