[HN Gopher] Satellites reveal widespread decline in global lake ...
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Satellites reveal widespread decline in global lake water storage
Author : _Microft
Score : 253 points
Date : 2023-05-19 08:56 UTC (14 hours ago)
(HTM) web link (www.science.org)
(TXT) w3m dump (www.science.org)
| seventytwo wrote:
| If weather patterns shift, the infrastructure built to store
| water will have to shift as well.
|
| Earth is a closed system, so we should expect to see water
| storage decline in some areas and flooding increase in some
| areas.
|
| It's all climate change stuff.
| eimrine wrote:
| > 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.
| [deleted]
| smeej wrote:
| 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.
| __MatrixMan__ wrote:
| It's easy to overlook the effects of transpiration, which
| is a result of photosynthesis, which is impacted by
| biodiversity loss. It short circuits water's path back to
| the ocean and puts it back into the air above land where it
| can precipitate into lakes a second time.
|
| Without it, snowmelt-fed rivers dry out earlier.
|
| As more ice melts there might be more liquid water
| available, but the ecosystems that would process that water
| into vapor are struggling. So you end up with a situation
| where the only source of water vapor in the air is the
| oceans.
|
| As temperatures increase that'll again be a net increase in
| ocean-driven evaporation, but it'll be less evenly
| distributed than evaporation+transpiration was.
|
| So the concern is that the only available water will be too
| salty to drink, or too destructive to capture.
| SkyPuncher wrote:
| The earth as a whole is roughly a closed system, but
| "usable water" is not.
|
| Most resource problems are not about the quantity of some
| thing changing as a percentage of earth's matter. Most
| resources are about density and composition.
|
| If all of the (non-ice) freshwater on earth was suddenly
| dumped into the ocean, we'd have the same amount of overall
| water - but little to no drinkable water.
|
| Likewise, we're not really creating new carbon by burning
| fossil fuels. We're moving and re-distributing it. Compared
| to being deep underground, the form we create by burning
| captures much more heat, causing many problems.
| eimrine wrote:
| > where you think the water will go, if not to other places
| on earth
|
| I afraid that a lot of fresh water is going to become an
| ocean water. Flooding theory creates the impression of
| transferring fresh water from one place to another where it
| will remain just as fresh. It is incredibly hard to create
| a fresh water from salty one.
| helge9210 wrote:
| > 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.
| fpesce wrote:
| 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 techniques even more
| crucial. As challenging as creating freshwater from
| saltwater may be, it's a puzzle we need to solve with
| urgency.
| flavius29663 wrote:
| 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.
| mrguyorama wrote:
| 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.
| mynameisvlad wrote:
| 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.
| NotYourLawyer wrote:
| This is where essentially all freshwater comes from.
| mynameisvlad wrote:
| That's great and all but how does that help with the
| issue of that freshwater being depleted? _Which is the
| topic at hand._
| NotYourLawyer wrote:
| I was responding to the "never in enough volumes to be
| actually usable by us" comment. Which is just completely
| wrong.
| mynameisvlad wrote:
| It's far from "completely wrong". Sure technically you
| are correct in that the rain _sometimes might_ land in a
| place that is usable by people, but practically speaking
| it 's nowhere near predictable or scalable enough to
| actually rely on, which is, once again, what is really
| being discussed here.
|
| As I said in another comment, talking about farmers using
| rainwater for their crops:
|
| > Rain is not predictable at the scale of a crop season.
| Rain is not scalable, it's extremely localized.
|
| > Rain happens, and when it does your crops get watered,
| but you can't in any way shape or form rely on that.
|
| So, congrats on being pedantic enough to miss the forest
| for the trees, I guess.
| NotYourLawyer wrote:
| >say something that's obviously false
|
| >someone points it out
|
| >"you're a pedant!"
| spenczar5 wrote:
| 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.
| mynameisvlad wrote:
| 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.
| 1234letshaveatw wrote:
| The rain can be captured by farms.
| mynameisvlad wrote:
| > in any sort of predictable and scalable manner.
|
| How?
|
| Rain is not predictable at the scale of a crop season.
| Rain is not scalable, it's extremely localized.
|
| Rain happens, and when it does your crops get watered,
| but you can't in any way shape or form rely on that.
| NineStarPoint wrote:
| About 80% of that rain happens back over the ocean, and
| then about 25% of the rain that happens over land
| actually gets captured as ground water. Even that isn't
| the main point though, the issue is we're currently using
| water faster than rain replenishes it in many places. At
| worst as I understand it, in some places they've
| collapsed their aquifers by over-pulling from them, and
| that means less of the rainfall in those areas will be
| recoverable in the future. At some point we have to enter
| a mode where we only pull water in a way that is
| sustainable or we'll suddenly find that we do indeed need
| desalinization to keep up with our use.
| vermilingua wrote:
| 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.
| ericd wrote:
| It also means a higher rate of evaporation from the
| oceans.
| vermilingua wrote:
| 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.
| XorNot wrote:
| 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 if the effect is
| rainfall hits the ocean, or say, flood-prone regions even
| harder then it normally does, it's still going to be coming
| down somewhere not useful to us.
|
| The problem is not that we _can 't_ solve these problems,
| it's that is is _staggeringly expensive_ to do so.
| HPsquared wrote:
| 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...
| PeterisP wrote:
| 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).
| HPsquared wrote:
| The figures assume a US citizen level of water
| consumption, someone on $2 a day would use much less than
| this.
| XorNot wrote:
| 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.
| bombcar wrote:
| People use water directly and indirectly. And water is
| "used" and "used" - it's not as simple as measuring a
| pipe, you need to know where it goes.
| HPsquared wrote:
| 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.
| mrguyorama wrote:
| Yeah maybe someday we can stop growing all our produce in
| the damn desert just because the weather was slightly
| more profitable.
| phpisthebest wrote:
| >>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
| nathan_compton wrote:
| I think many of us working in software can be
| overconfident about how easy it is to scale things,
| probably because of the peculiar progress in the
| improvement of integrated circuits and the commensurate
| increased availability of raw compute for not that much
| more energy. But many processes (including
| desalinization, as far as I understand it) are energy
| bound. It is really hard to make exponential progress
| when a process is bound by how much energy you can muster
| up to put into it. That is why rockets haven't had an
| exponential increase in the amount of weight they can get
| into orbit in the last 100 years. With gravity you must
| pay the piper.
|
| I doubt scaling desalinization is as hard as hurling
| stuff into space, but it may not be easy to scale either.
| There are plenty of places on earth which are very dry,
| adjacent to salt water, and extremely rich and yet no
| great desalinization technologies have come from them.
| MandieD wrote:
| _I think many of us working in software can be
| overconfident about how easy it is to scale things,
| probably because of the peculiar progress in the
| improvement of integrated circuits and the commensurate
| increased availability of raw compute for not that much
| more energy._
|
| You may have neatly (and politely) pinned down why we
| computer folks are so arrogant about how easy problems
| outside our direct field would be to solve, if only we
| were the ones "allowed" to solve them.
| excalibur wrote:
| > If nestle had to use Sea water to fill their bottles I
| bet they would have a cheap way to do it right quick
|
| Make it so.
| dghlsakjg wrote:
| There's the rules of physics to consider.
|
| There are more than a few places where desalination is
| necessary, and we still haven't come up with a way to
| make it cheap.
|
| The current issue is that there is just no way that we
| know of to reliably desalinate that isn't super energy
| intensive, so it comes down to trading energy for water.
| That's why desalination is expensive.
| XorNot wrote:
| > 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?
| xwdv wrote:
| We lose atmosphere to space everyday.
| seventytwo wrote:
| I'm sorry my model didn't account for your 8th order
| effects. You're technically correct.
| chmod775 wrote:
| And we also gain water from space through meteorites
| every day.
| neom wrote:
| The mesosphere has very little water in it.
|
| http://scienceline.ucsb.edu/getkey.php?key=2
|
| https://www.sciencedirect.com/topics/earth-and-planetary-
| sci...
| gonzo41 wrote:
| Earth isn't a closed system, we take in energy from the sun.
| jakswa wrote:
| Also we slowly lose upper atmosphere to the solar winds, when
| the magnetic fields fail to deflect it enough.
| _Microft wrote:
| That's not a problem. Closed systems can do that. If they
| additionally do not exchange energy with their environment
| they are called _isolated systems_.
|
| https://en.wikipedia.org/wiki/Closed_system
|
| https://en.wikipedia.org/wiki/Isolated_system
| neom wrote:
| https://www.unicef.org/emergencies/devastating-floods-pakist...
|
| https://en.wikipedia.org/wiki/2022_Pakistan_floods
|
| "in the recorded history [of the area] that we have since 1918,
| we have never had this much rain."
| paiute wrote:
| [flagged]
| lostmsu wrote:
| Can somebody explain why is this downvoted? If 53% decline,
| what do the other 47% do? How about total storage?
| fahadkhan wrote:
| Probably because it's ignoring the start of very next
| sentence in an attempt at sarcastic wit. >
| The net volume loss in natural lakes...
| paiute wrote:
| ... 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.
| dahart wrote:
| Yes of course the relationship between volume and area
| depends on the lake depth, are you suggesting the paper
| implied anything else? The Great Salt Lake has dropped
| rather dramatically in the last ten years, so much so
| that it has already changed pretty much all recreation
| and commercial activity on the lake - the primary boat
| dock closed because the marina was completely dry and by
| last year the shores had moved inward, by kilometers in
| some cases. Unusual precipitation this year has brought
| levels up a little, but this might only be a blip in the
| downward trend. The known reasons include drought
| conditions, unusually high temperatures, and greater
| upstream use. The Great Salt Lake's recent history very
| much backs up the claims of this paper, no?
| [deleted]
| _Microft wrote:
| 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 to papers than just their abstract.
| If you are curious, you can check section "Global LWS trends
| and drivers" for the answers to your questions.
| paiute wrote:
| 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.
| anigbrowl wrote:
| Maybe if you had articulated your objections up front
| instead of posturing, your subthread wouldn't now be
| sitting at the bottom of the page.
| dahart wrote:
| Your comments seem more skeptical than critical. Are you
| saying you believe lakes aren't losing volume?
| showdeadplease wrote:
| [dead]
| paiute wrote:
| This, and why 1992-2020? How many of these large lakes are
| distributed in say, Midwest America/Canada. What were the
| precipitation levels in that region just a few years prior?
| Why did they need to involve climate models when we have
| observable data?
| sjsdaiuasgdia wrote:
| Given the significant use of satellite data, I imagine the
| start point was chosen based on when some classes of data
| became available from recently launched satellites. An
| earlier time may not have sufficiently comparable data.
|
| There's a map linked in the paper if you want to see where
| the lakes are: https://www.science.org/cms/10.1126/science.
| abo2812/asset/ab...
| bjornlouser wrote:
| They used a technique for water segmentation described in
| an earlier paper [1]. The validation dataset for that
| method goes back to 1992...
|
| "All applied images have 30-m spatial resolution and were
| acquired during October 1, 1992 to October 31, 2018. The
| period was set with regard to the availability of the
| validation dataset"
|
| [1] Yao, J. Wang, C. Wang, J.-F. Cretaux, Constructing
| long-term high-frequency time series of global lake and
| reservoir areas using Landsat imagery. Remote Sens.
| Environ.232, 111210 (2019).
| Mbioguy wrote:
| History may not repeat but it does rhyme. Harappan civ thought to
| have declined due to less water. Petra once thrived due to a
| system of dams, cisterns, and water conduits, but never-repaired
| damage after an earthquake and increasing aridity meant it less
| and less supported urbanism and so declined. The Soviets
| overexploited the Aral Sea which has yet to (and will likely
| never) recover. It is now spoiling the surrounding region with
| dust storms carrying with them pollutants from industry that
| settled in the drying lakebed. Owens Lake in California once fed
| LA, but when it dried up it too caused polluting dust storms.
| Gov't has not learned from this history. The western US's water
| rights are outdated to the point of creating utterly backwards
| incentives. For example, Utah has use-it-or-lose-it water rights
| and the lion's share of water in the Great Salt Lake's watershed
| gets used to grow alfalfa. Alfalfa itself isn't necessarily a bad
| choice if you're going to grow stuff in an arid region, the issue
| is more how much of it is grown and in a wasteful way (little to
| no drip irrigation and no incentive to start using it, instead
| farmers are incentivized to flood areas during times of heavy
| rainfall or risk losing water rights). However even city and
| residential water use (a much smaller %) is still per capita
| wasteful compared to nearby Vegas which has done a much better
| job of becoming efficient in its water use. Utah got lucky this
| year in its snowpack, potentially buying some time to change, but
| is that gonna happen? No, they're praying for moisture and
| thinking their prayers got answered. Any guesses how long it'll
| be before the Great Salt Lake becomes the US/capitalism's Aral
| Sea? 5 years, 10, 15? Any techies wanting to move out here might
| think twice, homes without water and with seasonal arsenic-laden
| dust clouds probably won't have much resale value.
| juujian wrote:
| Damn, and that is with all the glaciers melting, which fills
| water reservoirs. Once they are completely gone, it is going to
| get so much worse.
| nathancahill wrote:
| Dam indeed.
| briantakita wrote:
| Where did the water go? The air? The biosphere? Lost to space?
| Underground oceans?
| wombarly wrote:
| Here in the Netherlands they decided to increase the water level
| of our lakes by 5cm to handle the drought season this year. Since
| the amount of snowfall in the Alps was lower than normal.
|
| https://www.rijkswaterstaat.nl/nieuws/archief/2023/04/hoger-...
| hbarka wrote:
| Do you have any news how Swiss lakes are affected?
| wombarly wrote:
| No, I only really know this because it was in the local news
| a while ago and though it was interesting / related to the
| OP.
| mywittyname wrote:
| It must be nice to live in a country that manages their natural
| resources with an eye towards long-term sustainability.
| TremendousJudge wrote:
| I live in a country with one of the richest water tables in
| the world. Due to (a forecasted!) drought and lack of
| planning we're literally running out of water to drink. It's
| like Saudi Arabia running out of oil, absolutely shameful.
| peteradio wrote:
| Isn't Netherlands bound to flood as ocean levels rise?
| hollander wrote:
| Maybe next century, but not anywhere soon.
| sangnoir wrote:
| 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.
| Scarblac wrote:
| 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.
| ethbr0 wrote:
| Since the 1400s; ref polder:
| https://en.m.wikipedia.org/wiki/Polder and https://en.m.w
| ikipedia.org/wiki/Land_reclamation_in_the_Neth...
| avisser wrote:
| The Afsluitdijk just got heightened and reinforced. As
| someone who's biked across it, I'm psyched because now
| you can bike on the North Sea side - previously, there
| was only 1 bike path on the Zuiderzee side.
|
| https://theafsluitdijk.com/projects/dike-
| reinforcement/how/
| 908B64B197 wrote:
| It's a conscious choice the citizens made every day for the
| last century, just like America chose freedom.
|
| What's the other countries excuses?
| avgcorrection wrote:
| Freedom from what? Britain?
| kyralis wrote:
| Freedom from facts.
| lovemenot wrote:
| Freedom Fries
| davidktr wrote:
| If they wouldn't, the Netherlands would literally not exist.
| Not only are large parts of the country below sea level,
| there is also the constant threat of flooding via Maas
| (Meuse) and Rhine. Raising levees is not enough, water
| management in the Netherlands must always look at the whole
| country.
| throw_pm23 wrote:
| With all due respect, the Netherlands is perhaps the furthest
| a place can be from long-term sustainability. The place is a
| mix of monoculture + concrete.
| gymbeaux wrote:
| It won't be nice when the country is invaded by another
| country for its water reserves. See: the Middle East
| pier25 wrote:
| We're going to need a lot of desalination plants powered by clean
| energy.
| wahnfrieden wrote:
| Like saying we need to recycle more to fix the landfill
| problem. Recycling fixes nothing with over consumption.
| linuxlizard wrote:
| When water gets in short enough supply, we will burn coal,
| garbage, tires, anything to power desalination plants.
| tppiotrowski wrote:
| Desalination cones should work in tropical climates.
|
| [1] http://www.watercone.com/product.html
| pier25 wrote:
| This is brilliant.
|
| The same designer made this Terracooler which is also a
| fascinating idea.
|
| http://www.terracooler.org/
| timerol wrote:
| Does this exist? The product page mentions that the planned
| price is "below EUR 20", but the news page doesn't have
| anything newer than 2007
| RC_ITR wrote:
| 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.
| bombcar wrote:
| Burning garbage may be one of the best things you can do
| with garbage -
| https://www.nytimes.com/2018/09/21/climate/sweden-garbage-
| us...
|
| As you can set it up to burn very hot and have all sorts of
| scrubbers on the outcomes.
| RC_ITR wrote:
| Burning _anything_ is never the right answer in a world
| of climate change.
|
| We are scrambling to find ways to capture atmospheric
| carbon and store it underground and burning garbage is
| literally the opposite of that.
| bombcar wrote:
| 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).
| RC_ITR wrote:
| 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.
| bombcar wrote:
| 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.
| [deleted]
| kzrdude wrote:
| That's a damn good argument for making sure we don't go into
| overpopulation.
| time_to_smile wrote:
| Problem is that _everything_ needs X powered by clean energy,
| which means we need both _a lot_ more clean energy and, if we
| want to slow /stop climate change, to massively reduce our use
| of fossil fuels... which requires _a lot_ more clean energy.
|
| We also, so far, globally have not shown any evidence of
| replacing fossil fuels with green energy, only supplementing
| them.
| acidburnNSA wrote:
| Direct carbon capture, electric vehicles, electric building
| heat, electric industrial process heat, and desalination are
| all massive new sectors that need to be powered that are
| barely on the radar of the existing electric grid.
|
| And we need more power to let emerging economies rise out of
| poverty, where having electric pumps and washing are truely
| life-changing from a quality of life perspective.
|
| So we need about 5x more total energy while also shifting
| from 80% fossil to 0% fossil.
|
| This is why I advocate for nuclear while most people advocate
| for wind and solar. We need advocates for all clean energy.
| Nuclear can actually use its own direct low-carbon heat to
| help with buildings (district heat) and industry, and that
| heat can also help in desal in some cases, though RO is the
| preference these days and doesn't really need that much heat
| input.
| anigbrowl wrote:
| Tidal power is a thing. Tidal power for ocean desalination
| eliminates the need for transmission infrastructure.
| Desalination has so many obvious upsides that I'm
| increasingly suspicious of the people insisting it's too
| difficult to contemplate, none of whom contribute anything of
| value to the discussion.
| Dennip wrote:
| 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.
| otikik wrote:
| That always looked like a no-problem to me. Can't the brine
| be put in a pool and let evaporate instead? You get drinking
| water from the desalination plant and salt.
| fshbbdssbbgdd wrote:
| The ocean is way too big for removing some drinking water
| (which is going to end up back in the ocean anyway) to have a
| material effect on the salt concentration.
|
| The problem is strictly local: if the brine produced by the
| plant is dumped in an area with low flow, it can hang around
| and affect sea life.
|
| If you use a big discharge pipe and put it a decent distance
| offshore in a current where it can mix effectively, there's
| very little effect.
|
| This is not a reason to shoot down desalination plants as a
| concept, it's a design constraint to take into account when
| building them.
| adgjlsfhk1 wrote:
| the hard part is what water of different salinity doesn't
| mix the way you think it should
| [deleted]
| dylan604 wrote:
| Instead of pumping the brine into a pool, pump it into a
| ship. As the ship sails, it slowly releases the brine at a
| rate much more tolerable. When the tanks are 50% empty, turn
| around and come home. lather rinse repeat.
|
| of course, a renewable powered ship
| RajT88 wrote:
| There are commercial salt harvesting operations which use
| such brine. No need to flush it back in the ocean.
|
| If you have ever flown into SFO you have seen the reddish
| pools. (By the way the red color comes from Brine Shrimp,
| which presumably there is also use for)
|
| https://www.atlasobscura.com/places/salt-ponds-san-francisco
| blacksmith_tb wrote:
| Which is good, but may not potentially scale up - if we
| were desalinating 5X, 10X as much seawater, it seems
| unlikely we could make use of that much salt, and would
| have to bury it or dispose of it some other way.
| RajT88 wrote:
| People are considering using salt as a building material
| now:
|
| https://www.archdaily.com/994769/could-salt-be-a-
| material-of...
|
| When you have a practically free resource which is waste
| from a large scale industrial process, cottage industries
| to make use of the free waste sometimes pop up. It's a
| solvable problem.
| Izikiel43 wrote:
| Then your house melts with the rain
| RajT88 wrote:
| Article talks about that kinda. You have to read at least
| halfway through it.
| p1mrx wrote:
| Look what you've done! I'm dissolving, dissolving! Ohh,
| what a world.
| wasm123 wrote:
| We had the same problem with power plants dumping hot
| untreated water back in the environment. This is why cooling
| towers are synonymous with nuclear power plants. This is an
| easy solution to fix, but like all engineering it costs
| extra. For power plants it was fixed through legislation. You
| literally have an entire oceans worth of water to
| reconstitute the brine. This was more problematic of older
| system using distillation.
| gonzo41 wrote:
| We pump brine inland to a large flat expendabe plain and
| flood it to allow the water to evaporate off and the salt to
| sette. 20-50 years later, pod racing on the salt flat.
| Dennip wrote:
| I think this causes its own host of issues as there are a
| load of other nasties such as arsenic etc in seawater which
| would build up there.
| djbusby wrote:
| Arsenic in Pod fuel too.
| _puk wrote:
| How does that work for e.g. small scale salt farming in
| many European countries that flood areas with sea water,
| then harvest the salt after the water has evaporated [0]?
|
| Is it just a case of the scale making it safe?
|
| 0: https://www.timeout.com/croatia/things-to-do/ston-
| salt-works
| aziaziazi wrote:
| I think so, yes. One person salt consumption seems wayyy
| less than the brime that would be created by desalination
| of the freshwater he needs.
| aziaziazi wrote:
| The desalination plan provide water when the groundwater
| reservoirs are too low to fulfill freshwater demand.
|
| The brine slowly go down through geological layers. After 5
| years it reaches groundwater reservoir.
|
| 20-50 years later, the regions become famous for its fun
| pod racing and for its numerous ghost cities around the old
| plain.
| piyh wrote:
| Put them down stream of farm runoff so everything is already
| dead
| dghlsakjg wrote:
| Farm runoff normally has the opposite effect, providing too
| many nutrients causing things like algal blooms.
| TeMPOraL wrote:
| So the brine and the farm runoff will cancel out and the
| result will be just right for nature. Right? _Right?_
| EvanAnderson wrote:
| Always a good time for[0]:
|
| Skinner: Well, I was wrong; the lizards are a godsend.
|
| Lisa: But isn't that a bit short-sighted? What happens
| when we're overrun by lizards?
|
| Skinner: No problem. We simply release wave after wave of
| Chinese needle snakes. They'll wipe out the lizards.
|
| Lisa: But aren't the snakes even worse?
|
| Skinner: Yes, but we're prepared for that. We've lined up
| a fabulous type of gorilla that thrives on snake meat.
|
| Lisa: But then we're stuck with gorillas!
|
| Skinner: No, that's the beautiful part. When wintertime
| rolls around, the gorillas simply freeze to death.
|
| [0] https://youtube.com/watch?v=P9yruQM1ggc
| swayvil wrote:
| Build cities from stabilized salt. Bricks, grout, pourable
| slabs.
| mistrial9 wrote:
| there is a second side to this systems-diagram, which is
| roughly.. conservation, efficiency, waste-reduction
| pier25 wrote:
| Yes but when glaciers melt completely and water deposits are
| empty we will struggle even with extremely efficient water
| systems.
| mattwest wrote:
| spoken like a true idealist
| jms703 wrote:
| Almond farmers. Am I right?
|
| /s
| Slava_Propanei wrote:
| [dead]
| hsuduebc2 wrote:
| It fascinates me how things have obvious consequences but human
| race just ignore them till literally everything is burning. As it
| is with water shortages, climate change or Hitler.
| mrtesthah wrote:
| A sizable majority (including in the US) recognize the danger
| of global warming, but are politically blocked from taking
| action by the actions of a small group of extremely wealthy
| individuals and corporations working to maintain the status quo
| to their benefit.
| myshpa wrote:
| The vital role of vegetation is often overlooked - we've
| significantly reduced forest cover over the past centuries.
|
| Global forest cover loss between 1990 and 2020 was estimated to
| be around 178 million hectares, representing a reduction of
| approximately 10% in the total global forest area.
|
| To restore water resources we should prioritize aforestation.
|
| https://ourworldindata.org/land-use#how-has-global-land-use-...
|
| 1700 ... 1 billion ha for agriculture
|
| 1800 ... 1.35 billion ha
|
| 1900 ... 2.54 billion ha
|
| 2016 ... 4.93 billion ha (=cca 50% of all habitable lands)
|
| https://ourworldindata.org/land-use
|
| Animal agriculture taking 75% of that.
|
| https://ourworldindata.org/land-use-diets
|
| "Beef is the leading driver of deforestation"
|
| https://ourworldindata.org/drivers-of-deforestation
|
| As Ernst Gotsch says: water is planted ('Agua se planta!')
|
| https://en.wikipedia.org/wiki/Ernst_G%C3%B6tsch
|
| https://en.wikipedia.org/wiki/Biotic_pump
|
| - Evapotranspiration: Vegetation influences the water cycle by
| releasing moisture into the atmosphere through transpiration,
| affecting cloud formation and regional rainfall patterns.
|
| - Surface runoff and infiltration: Vegetation intercepts
| rainfall, slowing down surface runoff and promoting better water
| infiltration into the soil, which helps mitigate drought
| conditions.
|
| - Shade and temperature regulation: Vegetation provides shade,
| lowers surface temperatures, and reduces evaporation rates,
| potentially alleviating drought intensity.
|
| - Feedback loops: Healthy vegetation enhances soil moisture
| levels, maintains humidity, and supports water resources, while
| stressed or absent vegetation can worsen drought conditions.
|
| - Forests and rainfall patterns: Forests contribute to local and
| regional rainfall by releasing moisture through transpiration,
| and their removal or degradation can disrupt precipitation,
| potentially contributing to drought.
| ooz16 wrote:
| 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 satellites--an area equivalent to the
| surface of Lake Superior, whereas 184,000 km2 of new water
| bodies, primarily reservoirs, were formed elsewhere (14)"
|
| My first impression was that this means there has been a growth
| in total permanent water area from 1984-2015. Am I just reading
| this wrong?
| neves wrote:
| I just think that if it was the case, Science Magazine would
| have changed the headline.
| explaininjs wrote:
| 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...
| MattGaiser wrote:
| > 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.
| explaininjs wrote:
| > But what percentage of the water we can actually use?
|
| What percentage of lake water could we use prior to literal
| millennia of engineering effort was put into moving it
| where we need?
|
| > most of our used water currently comes from
|
| This is technically true today, but barely. Nationwide
| roughly twice as much water comes from surface as the
| ground, but it varies dramatically by region. If you live
| in NY, 90% of your water already comes from the ground.
| It's certainly not the case that we're "locked in" to
| lakes, rather we are very capable of adapting to local
| conditions.
| ClumsyPilot wrote:
| > What percentage of lake water could we use prior to
| literal millennia of engineering effort was put into
| moving it where we need
|
| All of it, people built settlements on lakes and rivers
| for this very reason
|
| > It's certainly not the case that we're "locked in" to
| lakes, rather we are very capable of adapting to local
| conditions.
|
| No, we are locked in to rivers and lakes because thats
| the only big source of renewable fresh water. The
| underground aquifiers under midwest and under much of
| middle east will be gone in 50 years and will never
| return
|
| You should not incorrect people here without basic facts
| at your disposal
| explaininjs wrote:
| And yet they built aqueducts and wells too. Local surface
| water has been insufficient for civilization for at least
| 2000 years.
|
| > The underground aquifiers under midwest and under much
| of middle east will be gone in 50 years and will never
| return
|
| > You should not incorrect people here without basic
| facts at your disposal
|
| Nothing quite as HN as someone making bold alarmist
| unsupported assertions about the future of climate for
| all of time, then following it up with a sentence
| demanding an appreciation for "basic facts".
| wittenbunk wrote:
| Because obviously the amount of surface water is completely
| independent of the amount of subsurface water in aquifers. /s
| explaininjs wrote:
| What do you think the "obvious" correlation coefficient is
| between the two? Or even its sign? I suppose it'd be far
| too much to ask for the R value too.
|
| Science is supposed to answer these questions, instead this
| article carefully withholds information to make molehills
| into mountains.
| throwaway290 wrote:
| it sounds like new water bodies are man-made reservoirs, not
| permanent, e.g. the thing goes out into the ocean when the dam
| breaks.
| [deleted]
| abracadaniel wrote:
| 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.
| goatlover wrote:
| True, but we're rather capable of building long pipelines to
| ship liquids across large distances.
| MattGaiser wrote:
| 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.
| adhesive_wombat wrote:
| I was going to say "but that probably double-counts
| recycled water" and then I looked it up and recycled
| water is only 8% of Phoenix's water usage, and it's 10%
| nationally in the US.
| _3u10 wrote:
| Water isn't toxic though, aqueducts aren't built to
| anywhere near the standards of oil pipelines.
| LesZedCB wrote:
| > Globally, natural lake volume declined at a net rate of
| -26.38 +- 1.59 Gt year
|
| the phrase you read said "Over half (53 +- 2%) of the large
| lakes experienced _significant_ water losses " (emphasis mine)
| onlyrealcuzzo wrote:
| Is 26.38 Gt a lot?
|
| There's 91k cubic kilometers of fresh water in lakes
| according to: https://www.usgs.gov/special-topics/water-
| science-school/sci...
|
| And a cubic kilometer is basically a Gt, right? .98 Gt?
|
| So 26 / 91,000 = ~0.02% ?
|
| Is that a lot? If it's really 0.02% - wouldn't you expect
| _something_ to be random noise? How do we know it 's not
| random noise?
| time_to_smile wrote:
| > How do we know it's not random noise?
|
| A great place to start answering this question is _the
| article itself_. And if that doesn 't satisfy you, then the
| article also links to citations for all the claims it
| makes.
|
| It's great to not just blindly accept the claims of even
| experts in an area, but this reads more like someone who is
| working to not believe what they are being told.
| lovemenot wrote:
| I didn't read the parent's comment as you did. To me it
| looked like someone just trying to get a handle on the
| relative amounts and variability. They provided some
| relevant data and appeared open-minded.
|
| Your response to that added little to the discussion. You
| might have selected the parts of the article that
| answered those questions, but instead opted to shut down
| further discussion on a valid question. Which, may or may
| not be addressed in the sources.
| PM_me_your_math wrote:
| So we should have 100% faith in what we're being told in
| the article? If the author was trying to deceive then
| they wouldn't cite data that provided contradiction.
| Seems more like a religious approach than a logical one.
| There are papers, that were well cited, claiming there
| would be no sea ice by 2010, which never occurred.
| makz wrote:
| Dumb question: where did the water go?
| swayvil wrote:
| Global warming. Warmer air holds more water.
| djfobbz wrote:
| Midwest still holding winter temps in May...where's the
| warming part? Please refrain from posting "fact checker"
| links as we all know nothing comes free and they have their
| own vested interest in fact-checking.
| ROTMetro wrote:
| So you point to a change in your local normal climate as
| showing there isn't... climate change? Just trying to
| clarify what you are trying to say here?
| djfobbz wrote:
| Climate has always changed...it's a feature of the earth,
| not a bug...you being born is part of the climate change.
| When you decompose, that will also be part of the climate
| change. The magnitude of your so called calculations is
| minuscule compared to the life of earth and merely
| speculation just like stocks on Wall Street. Don't try to
| control something you did not invent. You're welcome!
| xen2xen1 wrote:
| 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.
| flavius29663 wrote:
| Global warming means generally more water in the air and more
| rain, not less. Think of Jurassic Park, not Mad Max
| ajmurmann wrote:
| Yes, more total rain. A steady steam from the mountains is
| a much better source of water though to keep lakes, rivers
| and our water supply going. The rain isn't evenly
| distributed through both space and time. We might get a
| drought for years and then torrential rainfalls. We are
| already seeing this. It's happened in California and
| Germany. Both places I'm most tide to. So maybe it's
| sampling bias. At my parent's in Germany, most fir trees
| are dead from the multi-year drought and then in June 2021
| half the village was destroyed by a flood.
| edu wrote:
| All over Europe, for sure.
| https://apnews.com/article/italy-floods-
| drought-59db3225a5d4...
| dghlsakjg wrote:
| I think it's pretty likely that the main cause is it's being
| diverted for agricultural use.
|
| Things like diversions into cities will also contribute, but
| generally gets dwarfed by agricultural use.
|
| The Colorado river flow for example is 80% agricultural. 20%
| for all other uses, including the bare trickle that actually
| makes it to the ocean
| aSockPuppeteer wrote:
| 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...
| peteradio wrote:
| I don't understand that telephone pole picture, the ground
| did not move around the telephone pole surely. I don't
| understand the graphics either. 1ft/year generally, but
| slower than that in the most extreme?
| croes wrote:
| They pump ground water that keads to sinking land, 1 foot
| per year.
|
| The pole is from 1977 or later but shows the historical
| land level of 1955 and 1925
| voakbasda wrote:
| When you remove the water from the ground, the drained soil
| compacts. The topmost sign on the pole pole shows where the
| ground level was 50 years earlier, caused by excessive
| taking of groundwater.
| [deleted]
| ajmurmann wrote:
| 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.
| briantakita wrote:
| 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...
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