Some of the World's Biggest Lakes Are Drying Up | Hacker News Reader

Some of the World's Biggest Lakes Are Drying Up

nationalgeographic.com

95 pointsprostoalex53 comments

Call me naive but I read the article as consequences of acute human expansion. Virtually every example was followed by explanations along the lines of “man made canals, irrigation, mining...”

I really think technology and better civil planning will be the way to fix these problems. Technology will cause the cost of renewable energy to trend towards zero while better civil planning will apply that energy to pump water from oceans to where it is needed by people. Eventually there will be success stories that will be copied around the world. Israel has had considerable success in water conservation and is considering replenishing the Dead Sea via canals.

If we can build oil pipelines from Canada to Texas eventually there will be a model that says we can build water pipelines from the pacific north west to Phoenix and Las Vegas. Governments around the world will either do something along these lines or they will not. Surely some will. Those that do will still be here long into the future, those that don’t will not.

China has invested billions in constructing mammoth aqueducts to do just this:

https://en.wikipedia.org/wiki/South%E2%80%93North_Water_Tran...

https://www.gokunming.com/en/blog/item/4038/china_considerin...

Meanwhile in Western Canada, we steadfastly refuse to sell water into the US, despite all of our fresh water running into the Pacific Ocean anyway...

> China has invested billions in constructing mammoth aqueducts to do just this

This is also the reason they invaded Tibet.

Maybe someone gave you water as a newly made up excuse for China taking Tibet?

But make no mistake about it, on October 7, 1950, the Chinese were not thinking about water. I'm fairly certain most historians would agree on that point.

What were they thinking about?

general access and control?

Here are two comments on r/askhistorians saying water was one of the reasons [1], along with natural resources in general [2].

Of course that's not the only reason; other answers make clear there were a lot of factors. Now though, Tibetan water is a huge issue, including for other countries downstream of Tibet including India and Pakistan [3]. There are no water treaties between these countries; China has been building a lot of dams and is planning a massive 600-mile pipeline to divert Tibetan water that would otherwise go to India [4].

Tibet is the third largest repository of fresh water after the two poles [5].

[1] https://www.reddit.com/r/AskHistorians/comments/35fuz5/leavi...

[2] https://www.reddit.com/r/AskHistorians/comments/2giaje/was_t...

[3] https://www.equaltimes.org/china-s-water-grab-in-tibet-risks

[4] https://qz.com/1114843/chinas-grand-plan-for-the-brahmaputra...

[5] https://www.theglobalist.com/tibet-and-21st-century-water-wa...

Anyone else feel like [3-5] should be a bigger issue? Desertification is scary as hell already but this is even more immediate.

In Canada there exists a widespread belief that if you start selling water, you have to sell it.

I am not sure this is correct, but it is widespread, and probably affects willingness to sell anything.

http://www.cbc.ca/radio/the180/more-on-nafta-and-water-parti...

It's nonsense. Even if NAFTA somehow forced the provinces to sell water at market rates to anyone who wanted to buy it, the revenue would accrue to the provincial government. Nothing would stop the provincial government from deciding to distribute this income as a dividend to all citizens. The end result is that the citizens of the province could definitely out-bid foreigners for the water, since the money they pay comes right back to them.

You can look for causes all you want. They all lead to human population growth.

Talking about it could possibly lead to finding something to do about it, which would mean deliberately lowering the birth rate. How? I don't know, but the alternatives are 1) hoping we get lucky and don't overshoot Earth's carrying capacity or 2) letting nature lower our population for us.

Regarding option 1, everyone knows population growth rates in many places (not everywhere) are declining, but the rates have nothing to do with Earth's carrying capacity, so it would only be luck if we stabilized below the carrying capacity. If we've already overshot it, lowering rates won't prevent option 2.

Option 2 means people dying prematurely from disease, famine, war, pestilence, etc.

Are there meaningful third options? Going to space or Mars doesn't lower the population here, and it presupposes that people could manage population growth on the spacecraft and early colonies. If we can there, we can elsewhere.

So however challenging figuring out how to lower the birth rate is, it seems the best option of the three. It seems like talking to you kids about birth control. It's easier not to talk about it, but the parents who don't do it end up with grandchildren sooner than they expect, and less cohesive families since they were chosen by circumstance, not deliberate choice.

A third option is to increase Earth’s carrying capacity. I don’t know how, but the capacity depends on technology and resource use, so it should be possible.

We have been doing that. But one problem is that it's easy to fool ourselves: you can temporarily raise carrying capcity by eating capital.

So, we catch many more fish now, for example. But we are catching at faster than replacement rate, depleting the natural capital stock.

Carbon energy + space in the atmosphere for CO2 is another variety of capital stock which we have used for temporary carrying capacity gains.

There are also long run carrying capacity improvements in the mix. General efficiency improvements fall in this category.

I'm in the camp that says the earth's carrying capacity is much higher than anything we're likely to reach.

I also believe that fertility rates are strongly tied to development, so that this problem will sort itself out if global development continues (especially in sub-Saharan Africa -- see maps [1] and [2]).

[1] https://en.m.wikipedia.org/wiki/Total_fertility_rate

[2] https://en.m.wikipedia.org/wiki/List_of_countries_by_GDP_(PP...

I have to admit i know nothing about this, so i want to ask what feels like a dumb question: What stops water from evaporating into space? I feel like the answer is something simple like "gravity", or "condensation", but we seem to think Mars once had water, so where is it now, and will that happen here too?

Gravity and a magnetic field. Gravity keeps the atmosphere from floating away, and the magnetic field protects it from getting stripped by solar radiation. The problem on mars is he magnetic field.

Magnetic field, ah! Right so, interestingly does that mean a polar shift (that every now and again people rave about) might have larger implications than breaking electronics? Ie massive water loss? I feel like it would depend what the poles look like after the shift, is it likely the field could be weakened or would it just flip? I should probably try learn more about this.

There are tiny losses from the upper atmosphere, but not enough to matter.

If you look at the water cycle[0], you'll see that as the water vapour rises it condenses - it gets quite cold a few miles up. Clouds consist of tiny droplets of liquid water and ice, not vapour.

[0] https://en.wikipedia.org/wiki/Water_cycle

Right, that makes sense, and i should have considered the extreme cold of the upper atmosphere. Thanks!

Where is the water going, though? Isn't water a zero-sum game in the sense that Earth is a closed system?

Not exactly. Ocean water isn't usable without removing the salt and other solutes. When a lake or river dries up, it may lose its bedrock and therefore, even when it rains again, the river no longer holds water. So you end up with the water spread out over land, which is useless - because we don't have tree-like roots to just suck low density water out of the ground. We rely on large pools to be efficient.

See levels are rising

Yes, but it is only a small contribution. Most of Earth’s liquid water already is in oceans. https://en.wikipedia.org/wiki/Water_distribution_on_Earth#Di...:

  - Oceans              96,5%
  - Antarctic ice sheet  1,56%
  - Lakes                0,013%

https://en.wikipedia.org/wiki/Antarctic_ice_sheet:

“Approximately 61 percent of all fresh water on the Earth is held in the Antarctic ice sheet, an amount equivalent to about 58 m of sea-level rise.”

⇒ completely emptying all lakes in the world into the sea would rise sea levels by half a meter or so.

Just like energy and entropy, it becomes harder to harvest efficiently. There's still just as much water, it's just not easily accessible. The difference between the water in your glass and the water in the cubic foot of earth after you spill your glass on it. You can't drink from the latter.

The water cycle does the collection for us (lakes, rivers, aquifers) but we're draining them faster than they can recharge, particularly problematic are the melting glaciers (in the Himalayas) and the aquifers:

https://en.wikipedia.org/wiki/Aral_Sea

https://www.washingtonpost.com/news/energy-environment/wp/20...

http://lcluc.umd.edu/hotspot/glacial-retreat-himalayas

https://www.nasa.gov/feature/goddard/2017/11-percent-of-disa...

https://www.jpl.nasa.gov/news/news.php?feature=4626

Thank you.

Surprised no one has mentioned Cape Town yet:

http://www.independent.co.uk/environment/cape-town-drought-d...

You don't need to go to South America, Asia or middle East - it's happening in Europe and no one seems to notice.

Look at Portugal and Spain, it's becoming a desert - the day of the cold wave the south of Portugal and Spain had the same temperatures of some country's in Africa.

People notice, but they feel helpless to stop it. Nobody wants to dwell on their impending doom, which ironically hasten their doom in this case.

They don't understand how bad it is, specially the government. For example, I don't understand why water intensive cultures are still being allowed.

The smell that comes from animal farms is so bad because there are no more black water pools - they can't even illegally dump it to rivers because there are no rivers to carry it.

It's getting beyond serious, this coming summer will result in the death of animals and ecosystems.

> the south of Portugal and Spain had the same temperatures of some countries in Africa

Tropical Africa, or are you saying the temperature in the south of Spain was comparable to the temperature in Morocco fourteen kilometers away?

I'm saying it had the same temperature (o was warmer even) then some parts of the north of Africa - not just Morocco: http://images.meteociel.fr/im/8481/temp_eur2_crn3.png

Spain mainland is separated from Africa by a mere 14 km strait, so no wonder temperature is similar, not talking about Canary Islands that are like a thousand km further to the south.

Southwest mainland is becoming a desert indeed, but that's nothing new. Most classic spagetti westerns were filmed there.

It's Sahara crossing the sea and a good thing for "plastic sea" (greenhouses). Almería provides several vegetables harvests a year that our European neighbourgs appreciate very much.

Just 200km west, you have permanent snow and big woods.

Uh, neither Spain or Portugal has ever had the same climate has the north of Africa - not at least in the recorded history.

Here's an example of the 27th of February: http://images.meteociel.fr/im/8481/temp_eur2_crn3.png

Climate != weather.

I'm sure you can find plenty of examples in recorded history when those areas had roughly the same weather.

I know the difference - but when a pattern of similar weather is noticed in the past 5-10 years, it's more than just weather, I believe it's climate.

What worries the most isn't how warm or cold it guets, it's precisely how dry it is.

No, you don't know the difference when you talk about climates and then link to the weather for a single day as supporting evidence.

The day was an example among a period of years of extreme drought.

Drought is the outcome of years of low precipitation - it's not one day, one week,one month or one year. The recovery won't come in the same time period I said in the previous sentence. It will take years of rain to refill what was lost, not to mention there might be erosion already that have made some riverbeds/lakes permeable again, so water will not be held there.

The spring of the main river in the Iberian Peninsula has dried. Many other springs of secondary rivers have dried as well.

It's not weather. It's climate change.

I don't know who you're debating. Your original comment used a reference to the weather to argue a point about climate. You can't do that, as your follow up comments clearly explain.

I can do this: > You don't need to go to South America, Asia or middle East - it's happening in Europe and no one seems to notice.

First sentence commenting an article about drought in several continents, yet they didn't mention Europe. So I stated such thing is happening in Europe.

> Look at Portugal and Spain, it's becoming a desert - the day of the cold wave the south of Portugal and Spain had the same temperatures of some country's in Africa.

In this sentence I state the example of Portugal and Spain - and gave an example of a day of extreme cold, snow and rain in Europe and parts of that territory (the iberian peninsula) had a day with temperatures similar to parts of Africa.

Saying I can't use weather to argue about climate is the same thing as saying I can't talk about anything which is the outcome of something else.

I'm not saying that because of that specific weather event in that day (or days) it set the climate for that region - I say it has a point of data. I gave you more - which is a clear example of a long term effect resulting from climate change - the drought of the main river.

Do you want more data points?

Not only neighbours, a big part of Eastern Europe in winter too. But the greenhouses also need a lot of water and that is getting scarce there, or not?

Cádiz, the most southern province in the mainland gets also the most rain. It's the Strait: every west wind from the Atlantic Ocean leaves the rain in the mountains woods there.

When the wind comes from the east (less often), it's usually warm and dry.

How much of the missing water is actually due to higher temperatures, and how much is due to people siphoning water from the aquifers that feed the lake? This article mostly focuses on "climate change" hysterics, but also acknowledges the siphoning problem.

A HN comment [0] linked to a TucsonWeekly [1] piece about how Tucson used to be an oasis. Similarly, the Salt River used to run year-round through Phoenix. Las Vegas was an oasis too. Cattle and wells turned Tucson's river dry. The Salt River is blocked by dams, where most the water is used for plants and allowed to evaporate. Las Vegas' population vastly exceeds its natural water supply. I don't think the disappearance of these cities' oases can be blamed on "climate change".

[0] https://news.ycombinator.com/item?id=16118109

[1] https://www.tucsonweekly.com/tucson/a-river-ran-through-it/C...

The Israelis are experts in hydroponics, which uses a fraction of the water used for irrigation. This is a more responsible way to use water in an arid country.

If the problem causing these lakes to dry up is mostly "climate change", these people's predicaments are hopeless. But if the problem is mostly irresponsible use of the aquifers upstream from the lake, the problem is solvable.

>This article mostly focuses on "climate change" hysterics

So what is your view on climate change? Is it that the climate is not getting warmer, or it might be but we don't know if it is or it isn't, or it is getting warmer but it is all due to non-human causes, or it is getting warmer but it might be due in part to human causes but we don't know, or it is getting warmer but it is beneficial? And all the views I just listed you think are wrong, do you believe the people who hold them are irrational, and do you argue against them?

Or is it that you don't care what people think and why, as long as they are opposed to governmental actions like reducing carbon emissions and promoting renewables?

One can fully agree that climate change is an important issue that needs to be dealt with, yet still have a problem with it being waved around irresponsibly on unrelated issues.

Right, I mean I'm a pretty hard core supporter of wildlands conservation, and I think this overemphasis on and exaggeration about climate change is gonna really hurt the environmental movement in about a decade.

Just like what happened with The Population Bomb and to a lesser extent Limits to Growth.

Maybe it's all of the above, much like ocean life is on the decline for multiple reasons including excess heat and acidification from excess CO2, but also including overfishing, pollution, and algae blooms due to fertilizer runoff.

I am wondering if mass-scale manufacturing & construction can solve this problem. Imagine large greenhouse-alike setups which spur vaporization, siphoning fresh water off into a lake. The sun would passively vaporize incoming salty water. Reaching m³s/minute of freshwater throughput would without doubt require massive scale. Since freshwater demand is increasing and supply decreasing, the economics of such project become more interesting every month.

Will such plan work at all?

This sounds like it has the same problem as salinization does. In most places conservation is cheaper.

Not to mention that conservation doesn’t use a ton of energy, most of which will be from burning fossile fuels. It’s a bit counterproductive if your plan to save the world burns a ton of coal, oil, etc to build and maintain.

... in the sense that the costs can just be imposed on people who can't defend themselves. And at that point, cheaper, more expensive ... ah what's the difference ?

I mean, that's a slightly different wording of the argument you're making.

In other words: this needs an economically viable solution. We need an absurdly cheap way to refill the lakes. Conservation isn't that, but everybody proposing it knows where the costs will go.

I’m curious who do you think is suffering now as a result of drought and diminishing ecological resources? Who is going to suffer through famine and drought? Your point is valid, but only insofar as people who can’t defend themselves always suffer. Every course of action hurts the group you’re concerned about, but the most likely to succeed and least damaging is conservation.

Well the problem is the large cities taking up all capacity in the rivers and the people who suffer are the people on the coastlines of those lakes.

The capacity in the rivers, by and large, is not taken up by people on those coastlines.

And conservation, I bet, "somehow" misses this reality. So it attempts to protect things like tourism income at the further expense of the victims. But nobody, absolutely nobody is talking about denying cities the water they depend on (which will dry up anyway, but not for a while yet ...).

You see the problem is not global warming. The problem is those cities and countries that take away the resources these lakes depend on. If you calculate the resulting change in precipitation from the 1 degree or so of temperature change we've seen, that's not what's making the difference here. The difference is those cities.

But of course, we "need to conserve". And what do we mean by that, exactly ? Why, the victims of it, the people living on that coastline, those need to be forced to abandon their lives, because otherwise the tourism that the rest of country profits from (but not so much those people), could get hit ... first a bit, then a lot. That's what we mean by conservation.

You didn’t even come close to addressing my question. I pointed out that your concern for the helpless is an obvious canard in this context, and you took that as a opportunity to engage in more ideological chatter.

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