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Satellites reveal widespread decline in global lake water storage

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Re: Satellites reveal widespread decline in global lake water storage

#31

Post by HPsquared »

XorNot wrote: post #14
smeej wrote: post #6

Earlier quoted context omitted.

I don't mean this to sound snarky. I'm genuinely curious where you think the water will go, if not to other places on earth.

Into the ocean. The ocean covers the majority of the Earth's surface. The ocean is full of salt. Water which rains out over the oceans is unusable as drinking or irrigation water without expensive processing (desalination). If historic rainfall patterns change, there is absolutely no requirement that the rain land anywhere useful for our existing infrastructure or human habitation. Yes, the water won't disappear, but…

Not staggeringly expensive, about 38 cents per day per person, apparently:

https://en.m.wikipedia.org/wiki/Desalination#Costs

Although that doesn't include irrigation..

EDIT: can even be economical for irrigation in some circumstances: https://www.fluencecorp.com/desalination-and-agriculture-les...

Re: Satellites reveal widespread decline in global lake water storage

#33

Post by paiute »

fahadkhan wrote: post #21
lostmsu wrote: post #19

Earlier quoted context omitted.

Can somebody explain why is this downvoted? If 53% decline, what do the other 47% do? How about total storage?

Probably because it's ignoring the start of very next sentence in an attempt at sarcastic wit. > The net volume loss in natural lakes...

... then they start talking about km^2 of lost surface area. Which if you read the paper they cite, it says "Between 1984 and 2015 permanent surface water has disappeared from an area of almost 90,000 square kilometres, roughly equivalent to that of Lake Superior, though new permanent bodies of surface water covering 184,000 square kilometres have formed elsewhere." On top of that, shallow lakes fluctuate wildly in surface area. The great Salt Lake for example. VS Lake Tahoe which can drop 10 ft and the surface area loss is tiny.

Re: Satellites reveal widespread decline in global lake water storage

#35

Post by aSockPuppeteer »

makz wrote: post #28

Dumb question: where did the water go?

Depends how close farmers are to water sources. They run high speed pumps at night or camouflage them in streams to get by water restrictions.

There’s the famous California telephone pole picture too. https://s3-us-west-1.amazonaws.com/themarinpost/emimg/1249/S...

Re: Satellites reveal widespread decline in global lake water storage

#36

Post by vermilingua »

smeej wrote: post #6
eimrine wrote: post #4

Earlier quoted context omitted.

> Earth is a closed system, so we should expect to see water storage decline in some areas and flooding increase in some areas. Of course, Earth is a closed system, but I am not sure it is that closed.

I don't mean this to sound snarky. I'm genuinely curious where you think the water will go, if not to other places on earth.

Higher global average temperatures means higher global average specific humidity. As the air warms it can hold more water vapour, which means less condensation. I don’t know how much difference this makes, but I expect it’s not insignificant.

Re: Satellites reveal widespread decline in global lake water storage

#37

Post by spenczar5 »

mynameisvlad wrote: post #27
helge9210 wrote: post #15

Earlier quoted context omitted.

> It is incredibly hard to create a fresh water from salty one. Fresh water is created from the salty water by evaporation all the time.

I mean, sure, but never in enough volumes to be actually usable by us. It’s not like we can capture every single evaporated water droplet before it cools to form fresh water. So while technically it happens all the time, practically it’s as if it isn’t happening at all when it comes to the concerns talked about here, specifically the quantity of available fresh water declining.

I think you are quite wrong about that. The evaporated ocean water becomes rain. Evaporated ocean water is the source of over 80% of all rain on earth.

Re: Satellites reveal widespread decline in global lake water storage

#38

Post by paiute »

_Microft wrote: post #24
lostmsu wrote: post #19

Earlier quoted context omitted.

Can somebody explain why is this downvoted? If 53% decline, what do the other 47% do? How about total storage?

I think this might be just because their comment is borderline useless - it is so condensed that one can hardly make any sense of it. So what did they want to say? Is it "Science, it works?" like in XKCD comic #54? Or are the quotes around science the actually important thing, casting doubt on it? It's hard to tell because they did not bother to spend a few seconds to actually write it out. Beside that there is more…

The intention was to get people to read the main thesis critically. That quote is sort of a tell about the quality of this paper, and the more I dig into this paper the more it confirms this is isn't good science.

Re: Satellites reveal widespread decline in global lake water storage

#40

Post by XorNot »

HPsquared wrote: post #31
XorNot wrote: post #14

Earlier quoted context omitted.

Into the ocean. The ocean covers the majority of the Earth's surface. The ocean is full of salt. Water which rains out over the oceans is unusable as drinking or irrigation water without expensive processing (desalination). If historic rainfall patterns change, there is absolutely no requirement that the rain land anywhere useful for our existing infrastructure or human habitation. Yes, the water won't disappear, but…

Not staggeringly expensive, about 38 cents per day per person, apparently: https://en.m.wikipedia.org/wiki/Desalination#Costs Although that doesn't include irrigation.. EDIT: can even be economical for irrigation in some circumstances: https://www.fluencecorp.com/desalination-and-agriculture-les...

Kind of leaving out the main point there. People don't use a lot of water. Industry and Farming do. We depend on both of those for...pretty much our entire society.
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