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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

#131

Post by bombcar »

RC_ITR wrote: post #128
bombcar wrote: post #110

Earlier quoted context omitted.

If handling waste and burying it costs X carbon, and burning it creates Y carbon, and Y is less than X, then burning is better than burying. You'd have to do the math, it's not manifestly obvious that it's not the case (especially once you consider all the transportation involved in sending waste around the country and across the ocean).

On first principles, there's no reason that the cost of transporting trash to the incinerator is any less carbon intensive than transporting trash to a landfill. Maybe people prefer incinerators in their community over landfills in their community (unclear), but if that's the case, that's a policy decision and not one that seeks to minimize carbon emissions.

Lots of recycling (has) been transported across the ocean to China.

It's likely that landfill are the way to go in many cases, but people don't like them.

Re: Satellites reveal widespread decline in global lake water storage

#132

Post by Scarblac »

sangnoir wrote: post #91
peteradio wrote: post #88

Earlier quoted context omitted.

Isn't Netherlands bound to flood as ocean levels rise?

The Netherlands been claiming land from the sea for centuries and some areas are already well below sea level - I don't think they'll neglect their dykes any time soon.

But we're also a river delta, we will run into problems long term because we'd have to pump entire rivers over the dykes.

Also salification and other problems with only pumping out all the time.

Re: Satellites reveal widespread decline in global lake water storage

#133

Post by mrguyorama »

flavius29663 wrote: post #50
fpesce wrote: post #18

Earlier quoted context omitted.

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.

But that's not actually helpful. Occasional massive rains don't refill aquifers very well. There needs to be a buffer to allow water to slowly make it's way into the system in a manageable way. Currently that is mountain snow melting over the warm season.

Re: Satellites reveal widespread decline in global lake water storage

#135

Post by briantakita »

ajmurmann wrote: post #48
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 gro…

Are there any studies on waterflow to/from underground oceans? It's difficult to understand how comprehensive a claim is without knowing the entire system.

> The subducting slabs also carry deep-sea sediments piggyback into the Earth’s interior. These sediments can hold large quantities of water and CO2. But until now it was unclear just how much enters the transition zone in the form of more stable, hydrous minerals and carbonates – and it was therefore also unclear whether large quantities of water really are stored there.

> The answer has now been provided by an international study. The research team analyzed a diamond from Botswana, Africa. It originated at a depth of 660 kilometers, directly at the interface between the transition zone and the lower mantle, where the dominant mineral is ringwoodite. Diamonds from this location are very rare, even among the extremely rare diamonds of super-deep origin, which account for just 1% of all diamonds. The studies found that the stone had a high water content due to the presence of many ringwoodite inclusions. The study team was also able to establish the chemical composition of the stone.

https://scitechdaily.com/an-underground-ocean-scientists-dis...

Re: Satellites reveal widespread decline in global lake water storage

#136

Post by mrguyorama »

HPsquared wrote: post #51
XorNot wrote: post #40

Earlier quoted context omitted.

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.

Water-intensive industrial processes can move to where the water is. Farming is more of a challenge but some crops need more water than others; there's a lot of scope for substitution.

Yeah maybe someday we can stop growing all our produce in the damn desert just because the weather was slightly more profitable.

Re: Satellites reveal widespread decline in global lake water storage

#137

Post by goatlover »

abracadaniel wrote: post #117
ooz16 wrote: post #106

Genuine question here. What would be the expected change over the same period? The abstract says 53% of lakes saw declines...does that mean 47% saw no change or gains? If so, that seems pretty close to net stable to me globally. Or frankly what we would expect to see (some gains, some losses) Also, this is stated later in the doc: "Between 1984 and 2015, a loss of 90,000 km2 of permanent water area was observed by sa…

That sounds reasonable. The water would have to go somewhere, but that alone could be catastrophic regionally. Cities are built around water sources, so having them move on timescales of human lifespans is worth worrying about.

True, but we're rather capable of building long pipelines to ship liquids across large distances.

Re: Satellites reveal widespread decline in global lake water storage

#138

Post by PeterisP »

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...

Something like 600 million people live below the poverty line, which with current inflation is at $2.15 per day; so for them a 38 cent per day rate means diverting almost 20% of their income just on water. For comparison, that's a much larger share than what USA residents spend on food (~13% of their income).

Re: Satellites reveal widespread decline in global lake water storage

#139

Post by MattGaiser »

explaininjs wrote: post #126
ooz16 wrote: post #106

Genuine question here. What would be the expected change over the same period? The abstract says 53% of lakes saw declines...does that mean 47% saw no change or gains? If so, that seems pretty close to net stable to me globally. Or frankly what we would expect to see (some gains, some losses) Also, this is stated later in the doc: "Between 1984 and 2015, a loss of 90,000 km2 of permanent water area was observed by sa…

The article also states “climate change and human activities increasingly threaten lakes that store 87% of Earth’s liquid surface fresh water”, but neglects to mention that only 0.3% of freshwater is liquid surface water in the first place. All in all a giant nothing burger, as with so many climate change alarmist “science” nowadays. https://www.usgs.gov/special-topics/water-science-school/sci...

> but neglects to mention that only 0.3% of freshwater is liquid surface water in the first place.

But what percentage of the water we can actually use? The Arctic and Antarctic are far away from most of us, and groundwater is limited and probably spread out quite a bit. Water vapour is hard to extract from the air.

You are trivializing it by saying it is just a tiny percentage of freshwater, but it is actually where most of our used water currently comes from.

Re: Satellites reveal widespread decline in global lake water storage

#140

Post by MattGaiser »

goatlover wrote: post #137
abracadaniel wrote: post #117

Earlier quoted context omitted.

That sounds reasonable. The water would have to go somewhere, but that alone could be catastrophic regionally. Cities are built around water sources, so having them move on timescales of human lifespans is worth worrying about.

True, but we're rather capable of building long pipelines to ship liquids across large distances.

It would require a lot of expansion for the required volume.

A barrel of oil has about 159 litres in it. The Keystone Pipeline would have transported 1.1 million barrels if it were fully expanded. 174,900,000 million litres per day. The City of Phoenix by itself uses about 1 billion litres per day.

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