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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

#41

Post by XorNot »

phpisthebest wrote: post #17
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…

>>it's that is is staggeringly expensive to do so. Necessity is the mother of all invention, and with Necessity also comes scale, and with scale comes less cost... Desalination has been expensive because it is not necessary, the second it becomes necessary I bet you will see the costs drop.. If nestle had to use Sea water to fill their bottles I bet they would have a cheap way to do it right quick

> If nestle had to use Sea water to fill their bottles I bet they would have a cheap way to do it right quick

Why? Nestle just passes the cost on to the consumer, because where else are they gonna go?

Re: Satellites reveal widespread decline in global lake water storage

#42

Post by ericd »

vermilingua wrote: post #36
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.

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.

It also means a higher rate of evaporation from the oceans.

Re: Satellites reveal widespread decline in global lake water storage

#43

Post by vermilingua »

ericd wrote: post #42
vermilingua wrote: post #36

Earlier quoted context omitted.

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.

It also means a higher rate of evaporation from the oceans.

True, but oceans only evaporate from the surface while the air retains moisture by volume. There is considerably more low, warm air than there is ocean surface.

Re: Satellites reveal widespread decline in global lake water storage

#44

Post by RC_ITR »

linuxlizard wrote: post #34
pier25 wrote: post #26

We're going to need a lot of desalination plants powered by clean energy.

When water gets in short enough supply, we will burn coal, garbage, tires, anything to power desalination plants.

Or (at least in the US), we will simply stop doing things like growing alfalfa in the desert to feed cows being raised in Texas. Sure beef will be a little more expensive but…

You’re actually right. We’ll probably burn garbage and radio hosts will call people against burning garbage effeminate names.

Re: Satellites reveal widespread decline in global lake water storage

#45

Post by algoatecorn »

mistrial9 wrote: post #39
pier25 wrote: post #26

We're going to need a lot of desalination plants powered by clean energy.

there is a second side to this systems-diagram, which is roughly.. conservation, efficiency, waste-reduction

spoken like a true idealist

Re: Satellites reveal widespread decline in global lake water storage

#46

Post by mynameisvlad »

spenczar5 wrote: post #37
mynameisvlad wrote: post #27

Earlier quoted context omitted.

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.

And most of that rain is going to go into the ocean again. Or be distributed in a large area. Neither of which can really be captured in any sort of predictable and scalable manner.

You know, unless we build a massive “roof” of devices to capture all that rain. Literally covering the entire planet. At that point yeah it would dev a reasonable thing to bring up in the context of fresh water reserves falling.

So I very much stand by the point that while, sure, it happens all the time, that does nothing to actually help with the topic at hand.

Re: Satellites reveal widespread decline in global lake water storage

#47

Post by flavius29663 »

xen2xen1 wrote: post #32
makz wrote: post #28

Dumb question: where did the water go?

We're changing the weather with greenhouse gases and whatnot, and we regularly pump it out to go to our homes, or even use it to make electricity with dams.

Global warming means generally more water in the air and more rain, not less. Think of Jurassic Park, not Mad Max

Re: Satellites reveal widespread decline in global lake water storage

#48

Post by ajmurmann »

makz wrote: post #28

Dumb question: where did the water go?

It's about sweet water. If it "goes away" it typically ends up in the ocean.

Previously it was in lakes, groundwater it glaciers. Glaciers which ultimately kept rivers flowing all year around even when not much snow falls in a given winter. Once all the glaciers are melted, the rivers can dry up completely. The glacier water has already made it to the ocean and doesn't need to travel there anymore via river. With groundwater depleted, we cannot use that anymore to substitute and some sources of creeks will dry up.

Re: Satellites reveal widespread decline in global lake water storage

#49

Post by Dennip »

pier25 wrote: post #26

We're going to need a lot of desalination plants powered by clean energy.

IIRC These can have thier own host of problems because the 'brine' byproduct doesn't mix well back into the ocean and can settle/pool and create marine dead zones. Although suppose that will be less of a priority if people are thirsty.

Re: Satellites reveal widespread decline in global lake water storage

#50

Post by flavius29663 »

fpesce wrote: post #18
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.

Indeed, and it's interesting to note that this natural desalination process also incorporates long-term storage mechanisms. Historically, vast quantities of freshwater have been stored in the form of snow packs and glaciers. However, in our changing climate, this storage is not occurring at the same scale as it used to. This could potentially exacerbate future water scarcity issues, making man-made desalination techn…

on the other hand, global warming will pump much more water in the atmosphere, and we will have more precipitation. In fact, global warming would not be a problem at all if what I said above was not true. CO2 alone could only raise the temperature by 1C no matter how much we would put in the air (by year 2100). The water vapor creates a positive feedback loop that warms it far beyond what CO2 can do alone.
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