More data requested on Tarim Basin hidden water

[studiot]

Does anyone have more up to date information on the  underground water system in the Tarim Basin China which is alleged to operate as a giant carbon sink ?

Quote

Huge hidden ocean under Xinjiang’s Tarim basin larger than all Great Lakes combined

The ocean acts as a major carbon sink, sucking up CO2 and preventing even greater climate change

Full 2015 article here

https://www.scmp.com/tech/science-research/article/1845192/huge-hidden-ocean-under-xinjiangs-tarim-basin-larger-all-great

Edited October 11, 2019 by studiot
spelling

[mistermack]

I'd like to know how it "sucks up" CO2.

" Around 10 years ago, Li’s team discovered large amounts of carbon dioxide disappearing in Tarim, with no explanation over where it could be going ."

How the hell did they discover that? It doesn't sound very likely. 

What it does sound like is the old phenomenon of scientists tacking on a global warming angle to their work, because that's where the research grant money is these days. 

[CharonY]

On 10/11/2019 at 3:39 PM, studiot said:

Does anyone have more up to date information on the  underground water system in the Tarim Basin China which is alleged to operate as a giant carbon sink ?

There is quite a bit work out there focusing on stable isotope work, but not specifically regarding carbon sinking (though one might find some with some digging). A good way to check whether there are updates on a given topic is to look at papers which have cited a study in question. Much of the papers are discussing the role of deserts and semi-arid regions for carbon sinking rather than the Tarim Basin specifically (e.g. Schlesinger Global Change Biology 2016).

 

 

On 10/12/2019 at 12:34 PM, mistermack said:

How the hell did they discover that? It doesn't sound very likely. 

What it does sound like is the old phenomenon of scientists tacking on a global warming angle to their work, because that's where the research grant money is these days. 

And this sounds like someone making assumptions without putting any thoughts into it. They obviously described their methodology in their paper.

[studiot]

11 hours ago, CharonY said:

There is quite a bit work out there focusing on stable isotope work, but not specifically regarding carbon sinking (though one might find some with some digging). A good way to check whether there are updates on a given topic is to look at papers which have cited a study in question. Much of the papers are discussing the role of deserts and semi-arid regions for carbon sinking rather than the Tarim Basin specifically (e.g. Schlesinger Global Change Biology 2016).

Thank you for this comment on my question, I will follow it up.

 

On 10/12/2019 at 7:34 PM, mistermack said:

I'd like to know how it "sucks up" CO2.

" Around 10 years ago, Li’s team discovered large amounts of carbon dioxide disappearing in Tarim, with no explanation over where it could be going ."

How the hell did they discover that? It doesn't sound very likely. 

What it does sound like is the old phenomenon of scientists tacking on a global warming angle to their work, because that's where the research grant money is these days. 

 

Before I came across the China article I had not given any consideration to the thought of getting carbon dioxide into groundwater but thinking about it I realise that it must happen and, more to the point, the uptake rate will likely increase in any water desert areas.

Carbon dioxide is mildly soluble in water, obviously more so in conditions where the resulting acid can be withdrawn eg by reaction with carbonate rocks.
The equilibrium is a dynamic one and over the open ocean the water (at the top at least) will be fully saturated with carbon so the net solution rate will be low.
The oceans remove so much CO2 simply because they are so vast and of course because of the photosynthesising life in them.

In the ground we have vadose water (vadose  = german for wandering) above the phreatic surface ( = water table)

https://www.google.com/search?q=vadose+water&ie=utf-8&oe=utf-8&client=firefox-b

In this region the saturated ground below the water table is in gaseous equilibrium with the air in the soil or rock pores.
So it will take up CO2.
Here is your mechanism.

I suppose that in desert areas there is a mostly dearth of groundwater, so if there is a large subsurface reservoir it will be working pretty hard extracting CO2.

 

Thank you for your reply, I am sorry that you received 2 downvotes as a result of answering my thread, perhaps your last line was too strident and perhps was taken to suggest they are all like this, though I am sure that some have chosen the easy route to obtain grant money on a bandwagon subject.
But certainly not all, there are definitely seriousnplayers out there as well.
So here is a +1 as partial compensation.

 

I would welcome any further conversation on the subject.

[CharonY]

5 hours ago, studiot said:

Thank you for your reply, I am sorry that you received 2 downvotes as a result of answering my thread, perhaps your last line was too strident and perhps was taken to suggest they are all like this, though I am sure that some have chosen the easy route to obtain grant money on a bandwagon subject.
But certainly not all, there are definitely seriousnplayers out there as well.

While I have not provided any negative reps, I want to clarify that there is no easy route to grant money. No proposal will be funded based on the topic alone. They all require rigorous review. The only "easier" route is if the PI in question has a strong reputation, as their suggestions to perform research will have more weight than a newcomer. I.e. regardless of the topic, the methodology has to be sound. You cannot just put cancer or global warming on your grant and expect money rolling in.

Moreover, the actual research once conducted will also undergo review, a system that is entirely independent of funding mechanisms. To suggest that there is an easy way to get funded and publish in a mainstream journal is laughable. Well, there are actually examples of something like that happening, but they were cases connected Koch industries who bankrolled researches to find evidence against global warming.

[studiot]

5 hours ago, studiot said:

I would welcome any further conversation on the subject.

 

The subject being the takeup of CO2 in desert conditions.
In fact I devoted 7 paragraphs in my last post to that as against the four lines to an aside, which I maintain offers a balanced view of that aside, before putting it fully aside.

[CharonY]

Fair enough,  though it is part of a larger movement to discredit science (i.e. that folks are just doing bandwagon science), which is an ongoing and rather disruptive trend and (IMO) needs at least to be noted when encountered. It also poses the dangers of the "both sides" discussion which as beset science in all kind of subjects, ranging from evolution to vaccination. It simply has no place here.

Now then:

A key to the Tarim basin seems to be salinity, which increased CO2 uptake by the water with  dissolution  of soil carbonate and subsequent storage. So at least for that particular system it may be somewhat explainable, though from what I can see (with limited expertise) is that it is a hypothetical at this point..  However, there is a body of literature out there indicating that carbon sink rates are found to be rather high in certain arid and semi-arid regions. So far, there does not seem to be a consensus on possible mechanisms, which include the applicability of certain techniques to desert systems. In other words, it is not entirely clear. 

6 hours ago, studiot said:

(vadose  = german for wandering)

Also to nitpick, vadose is not a German word. AFAIK it is derived from the Latin vadosus/a/um (shallow). It is probably also related to the Latin word vadere (wandering).

[studiot]

1 hour ago, CharonY said:

 

A key to the Tarim basin seems to be salinity, which increased CO2 uptake by the water with  dissolution  of soil carbonate and subsequent storage. So at least for that particular system it may be somewhat explainable, though from what I can see (with limited expertise) is that it is a hypothetical at this point..  However, there is a body of literature out there indicating that carbon sink rates are found to be rather high in certain arid and semi-arid regions. So far, there does not seem to be a consensus on possible mechanisms, which include the applicability of certain techniques to desert systems. In other words, it is not entirely clear. 

 

Thank you for this response.

Did you catch my point that in arid/semiarid regions there will be next to no vadose water and the phreatic surface will be a long way down in general?
Unless there are substantial underground waters as reported by the Chinese.

So here is a credible mechanism.

 

 

1 hour ago, CharonY said:

Fair enough,  though it is part of a larger movement to discredit science (i.e. that folks are just doing bandwagon science), which is an ongoing and rather disruptive trend and (IMO) needs at least to be noted when encountered. It also poses the dangers of the "both sides" discussion which as beset science in all kind of subjects, ranging from evolution to vaccination. It simply has no place here.

 

I prefer Eric Lerner's explanation that Science has discredited itself.

Advertiser no longer use HI Tech as a selling point because the general public have become disillusioned with Science, and many of the attempts by the scientific community to fix it have made matters worse, not better.
And that is even granted the resurgence of evangelical fundamentalism in the Bible Belt.

1 hour ago, CharonY said:

 

Also to nitpick, vadose is not a German word. AFAIK it is derived from the Latin vadosus/a/um (shallow). It is probably also related to the Latin word vadere (wandering).

Interesting.

My lecturer at the City of London University, all those years ago gave that derivation.
Certainly there is a German word wanderin and derivatives which means to roam and corresponds roughly to the English word wanderer.
But, of course the Germans pronounce w as we pronounce v.
However much of the German language come directly from Latin.
And my Oxford has vadose coming from the Latin vadosus = shallow.
So you may well be right. There is probably a common root here in the Latin.

Thank you for that correction.

 

 

[CharonY]

1 hour ago, studiot said:

Did you catch my point that in arid/semiarid regions there will be next to no vadose water and the phreatic surface will be a long way down in general?
Unless there are substantial underground waters as reported by the Chinese.

So here is a credible mechanism.

Well, the lit discusses a variety of pumping mechanisms and possible flaws in  the  models , but since they are not within my realm of expertise I am not really able to speculate much about that. It does get very technical very quickly and perhaps someone else with more background in geology and/or biogeochemistry could add something here.

 

1 hour ago, studiot said:

Certainly there is a German word wanderin

Just another nitpick, the word is "wandern" . There is also "waten" which translates to "wade" which probably are derived from the same Latin source.

 

Quote

I prefer Eric Lerner's explanation that Science has discredited itself.

Advertiser no longer use HI Tech as a selling point because the general public have become disillusioned with Science, and many of the attempts by the scientific community to fix it have made matters worse, not better.
And that is even granted the resurgence of evangelical fundamentalism in the Bible Belt.

I feel that is an important discussion in itself. With your permission I would like to split that off in a new thread and talk about that a bit.

[studiot]

11 minutes ago, CharonY said:

perhaps someone else with more background in geology and/or biogeochemistry could add something here.

hope so

12 minutes ago, CharonY said:

Just another nitpick, the word is "wandern" . There is also "waten" which translates to "wade" which probably are derived from the same Latin source.

You have me there.   You've spotted the spelling mistake. There is a spling mistake in every studiot post.

13 minutes ago, CharonY said:

I feel that is an important discussion in itself. With your permission I would like to split that off in a new thread and talk about that a bit.

Sounds good to me

[mistermack]

Still sounds like a highly dubious claim to me. Firstly, how does an underground lake "suck" CO2 out of the air? 

Yes, rain falls on the mountains, and it contains CO2 dissolved, as it always does. I don't call that "sucking", it's just normal rain. It happens all over the world. 

There seems to be large reserves of water under a lot of deserts worldwide. Gadafi spent a fortune building a pipeline to transfer fresh water from beneath the Sahara to the more populous coastal areas. Australia has huge quantities of slightly saline water under it's surface called the Great Artesian Basin, which I first learned about sixty years ago. 

 

[zapatos]

1 hour ago, mistermack said:

Still sounds like a highly dubious claim to me. Firstly, how does an underground lake "suck" CO2 out of the air? 

Yes, rain falls on the mountains, and it contains CO2 dissolved, as it always does. I don't call that "sucking", it's just normal rain. It happens all over the world. 

It's an analogy. No one is suggesting that a person is using their mouth to cause a partial vacuum thus drawing in the CO2. 

[studiot]

8 hours ago, mistermack said:

Still sounds like a highly dubious claim to me. Firstly, how does an underground lake "suck" CO2 out of the air? 

Yes, rain falls on the mountains, and it contains CO2 dissolved, as it always does. I don't call that "sucking", it's just normal rain. It happens all over the world. 

Nor do I.There is no such process as 'suction' in the known universe.
Suction is just a convenient fiction, like centrifugal force.
The proper desciption is usually best, IMHO.
 

In any case I was not referring to suction.

I am not sure you have caught the mechanism I was referring to.

In the diagram consider two vessels, both open to the atmosphere.
One contains a substantial amount of water.
The other has just a thin film of water on the bottom.

Which bowl of water will absorb the most carbon dioxide?

Now place a large bath sponge over each bowl, covering the water.

Again which bowl will absorb the most carbon dioxide?

 

Clearly the one with the most water in both instances.

 

Here is the mechanism I suggest.

 

[mistermack]

Studiot, you have a naiively simplistic view of what is happening. The CO2 falls with the rain. What is in your bowl really doesn't matter much. In the real world, the water has to go somewhere. If there is no sponge, it finds a new home. If this underground "lake" didn't exist, the rain water would still find somewhere to exist. In any case, the chances are that the lake is full, and what seeps in at one end is seeping out at the other end. 

From memory, I believe that there is more water in the rocks of the Earth than all the oceans and rivers combined, estimated from twice as much, to ten times as much, so this "lake" is not exactly earth shattering news. 

[studiot]

21 minutes ago, mistermack said:

Studiot, you have a naiively simplistic view of what is happening. The CO2 falls with the rain. What is in your bowl really doesn't matter much. In the real world, the water has to go somewhere. If there is no sponge, it finds a new home. If this underground "lake" didn't exist, the rain water would still find somewhere to exist. In any case, the chances are that the lake is full, and what seeps in at one end is seeping out at the other end. 

From memory, I believe that there is more water in the rocks of the Earth than all the oceans and rivers combined, estimated from twice as much, to ten times as much, so this "lake" is not exactly earth shattering news. 

 

Please, you started your involvement with this discussion so well, as I already noted.

So don't spoil it by drawing you 'Science' from illeterate Daily Mirror journalists.

Carbon dioxide does not fall with the rain.
Some aerial carbon dioxide does indeed dissolve in rainwater.
But then it is no longer carbon dioxide.
It is carbonic acid.

However we are talking about desert conditions.
And in my school a desert was a place where there is little or no rain or surface water in general.

The process I am offering is entirely separate from this and will not work well in say the gault clay in the London basin, despite the plentiful rain in that region.

As to the quantity of water contained within the rocks, this has been a matter of debate for more than a century.

As 2/3 of the surface of the Earth is covered with open ocean, to a depth of some miles in some places (google tells me the average depth is 3688 metres),
This leaves only 1/3 of the top surface of the Earth to hold both rock and water.
Clearly there is more water not in the rock in this bit.

So if, and it is a big if, there is any more water, that water is a very long way down and outside our discussion.
Furthermore none of such deep water will be in any sort of contact with atmospheric carbon dioxide.

 

 

[mistermack]

3 minutes ago, studiot said:

Carbon dioxide does not fall with the rain.
Some aerial carbon dioxide does indeed dissolve in rainwater.
But then it is no longer carbon dioxide.
It is carbonic acid.

When people start this kind of nit-picking about words, it signals to me that their hold on the argument is weak. 

I assumed that anyone reading this thread would already know the above. However, if it's that important to you to point it out, give yourself a brownie point. Even though the climate industry constantly refers to dissolved carbon or carbon dioxide. I hope you will trawl the literature and constantly put them all right.  😊

10 minutes ago, studiot said:

However we are talking about desert conditions.
And in my school a desert was a place where there is little or no rain or surface water in general.

So what? The great artesian basin is kept topped up by rain in the mountains. The Sahara water is fresh, so it fell as rain at some point. I don't see what point you are making. Calling water a carbon sink ( sorry, CARBONIC ACID sink 😕) is like calling it a water sink. Once it dissolves the CO2 in the air, it's just part of a natural cycle that's been happening for millions of years. 

What these people have really found is some porous rock. Nobody would normally be interested, so they mention CO2 and hey presto, it's a story.

If someone finds a cheap way to desalinate it, it might actually be important one day.

[dimreepr]

15 minutes ago, mistermack said:

When people start this kind of nit-picking about words, it signals to me that their hold on the argument is weak. 

I assumed that anyone reading this thread would already know the above. However, if it's that important to you to point it out, give yourself a brownie point. Even though the climate industry constantly refers to dissolved carbon or carbon dioxide. I hope you will trawl the literature and constantly put them all right.  😊

So what? The great artesian basin is kept topped up by rain in the mountains. The Sahara water is fresh, so it fell as rain at some point. I don't see what point you are making. Calling water a carbon sink ( sorry, CARBONIC ACID sink 😕) is like calling it a water sink. Once it dissolves the CO2 in the air, it's just part of a natural cycle that's been happening for millions of years. 

What these people have really found is some porous rock. Nobody would normally be interested, so they mention CO2 and hey presto, it's a story.

If someone finds a cheap way to desalinate it, it might actually be important one day.

Do you own/work in a coal mine/oil field, or other vested interest?

Otherwise, WTF are you so determined to discredit any attempt to highlight the fact of AGW?

[StringJunky]

13 hours ago, mistermack said:

Still sounds like a highly dubious claim to me. Firstly, how does an underground lake "suck" CO2 out of the air? 

Yes, rain falls on the mountains, and it contains CO2 dissolved, as it always does. I don't call that "sucking", it's just normal rain. It happens all over the world. 

There seems to be large reserves of water under a lot of deserts worldwide. Gadafi spent a fortune building a pipeline to transfer fresh water from beneath the Sahara to the more populous coastal areas. Australia has huge quantities of slightly saline water under it's surface called the Great Artesian Basin, which I first learned about sixty years ago. 

 

Some sort of disequilibrium favouring movement of carbon dioxide in that direction.

Edited October 20, 2019 by StringJunky

[mistermack]

45 minutes ago, dimreepr said:

WTF are you so determined to discredit any attempt to highlight the fact of AGW?

You love a derail.  I'm replying to the OP and the relevant replies to my post. 

If you want to debate AGW, start an AGW thread. I won't post, because it's like religion, and there's nobody here adult enough to debate it dispassionately. 

But for the record, I don't deny the fact of AGW.  But I certainly don't accept the claimed extent of it, or the claimed future extent of it. 

[dimreepr]

3 minutes ago, mistermack said:

But for the record, I don't deny the fact of AGW.  But I certainly don't accept the claimed extent of it, or the claimed future extent of it. 

That, once again, doesn't answer my question. But fair enough, I don't want to derail the thread; I'll leave that to you...

[studiot]

1 hour ago, mistermack said:

So what? The great artesian basin is kept topped up by rain in the mountains.

Indeed so what?

The great artesian basin is almost as far below sea level as the tarim basin is above, both distances simlar to the height of England's highest mountains.

But the difference is that there is surface water farming and so on in the GAB (google has lots of pics).
But the Tarim is a desert.
So no surface water, no farms, just sand dunes (again google has lots of pics)

1 hour ago, mistermack said:

Calling water a carbon sink

Carbon sink is really another journalistic term but has value as a general term that "carbon dioxide falling with rain does not".

Science is about appropriate accuracy.

But why are you arguing about minor issues whilst completely avoiding the main subject in this thread ?

Which was, to refresh your memory,

13 hours ago, mistermack said:

Still sounds like a highly dubious claim to me. Firstly, how does an underground lake "suck" CO2 out of the air?

 

Being dubious is fine and scientific,
But ignoring the answer provided to your specific question several times is not.

[mistermack]

On 10/20/2019 at 3:26 PM, studiot said:

Being dubious is fine and scientific,
But ignoring the answer provided to your specific question several times is not.

To be honest, I'm not aware of such an answer in this thread. The closest I've seen is this : 

On 10/15/2019 at 11:00 AM, studiot said:

In this region the saturated ground below the water table is in gaseous equilibrium with the air in the soil or rock pores.
So it will take up CO2.
Here is your mechanism.

I suppose that in desert areas there is a mostly dearth of groundwater, so if there is a large subsurface reservoir it will be working pretty hard extracting CO2.

But all it is is claims. Claims don't make an answer for me. You need to provide evidence of where the extra CO2 is coming from in the first place, and why. And what concentrations, and how they are different to the original concentration that soaked in as melt water. 

There's nothing in the linked article to any of that. It's just full of "could be"s. The first sentence starts with "there could be". The next has "could be equivalent". 

If any thread belongs in speculations, this is it. But some facts and figures "could" change all that.

[studiot]

43 minutes ago, mistermack said:

On 10/20/2019 at 3:26 PM, studiot said:

Being dubious is fine and scientific,
But ignoring the answer provided to your specific question several times is not.

To be honest, I'm not aware of such an answer in this thread. The closest I've seen is this : 

On 10/15/2019 at 11:00 AM, studiot said:

In this region the saturated ground below the water table is in gaseous equilibrium with the air in the soil or rock pores.
So it will take up CO2.
Here is your mechanism.

I suppose that in desert areas there is a mostly dearth of groundwater, so if there is a large subsurface reservoir it will be working pretty hard extracting CO2.

But all it is is claims. Claims don't make an answer for me. You need to provide evidence of where the extra CO2 is coming from in the first place, and why. And what concentrations, and how they are different to the original concentration that soaked in as melt water. 

There's nothing in the linked article to any of that. It's just full of "could be"s. The first sentence starts with "there could be". The next has "could be equivalent". 

If any thread belongs in speculations, this is it. But some facts and figures "could" change all that.

 

You asked and I answered.

At least you have identified my original description.

But if you did not understand it (as you clearly don't or won't)

Then why not just ask for greater detail instead of mocking ?

I am always happy to try to rephrase my words in a way that is comprehensible to the reader.

 

So let me try one last time.

If there is no water at all (zero water) How much CO2 will be dissolved?

If there is a small amount of water How much CO2 will be dissolved?

If there is a large amount of water How much CO2 will be dissolved?

 

 

[CharonY]

On 10/20/2019 at 8:26 AM, studiot said:

Carbon sink is really another journalistic term but has value as a general term that "carbon dioxide falling with rain does not".

Actually no, it a commonly used term in global cycles to describe reservoirs which accumulate and store a given compound (carbon in this case). Any sufficiently large body can act as a carbon sink (regardless of rain) as CO2 exchange with the atmosphere only happens at the surface. If the water is cold, more CO2 is dissolved than released, if it heats up again more CO2 is emitted (ignoring biological fixation for now). As such, deep cold bodies of water can act as a net carbon sink.

The paper by Li et al. (i.e. the one referenced by OP) have found that dissolved inorganic carbon also be sequestered into enodrheic basins. A important mechanism that was observed is that CO2 from soil is being dissolved in the highly saline (and alkaline) water into groundwater aquifers and transported to a terminal lake. The salinity is an important element here as the higher alkalinity allows increased CO2 solubility. They found that source water (i.e. rain snow melt etc.) were basically carbon free, but the groundwater was high in dissolved carbon. That showed that during the transport of water to the basins, they dissolved singificant amount of carbon along the way (i.e. we have mechanism often described as carbon pump into the mentioned carbon sink). Carbon dating experiments showed that the dissolved carbon most of it was fairly young, resulting from soil respiration.

Similar mechanisms have been proposed for other terminal lakes and I found a follow-up paper that escaped my notice earlier: Li et al. Nature Geoscience volume 10, pages501–506 (2017)

[studiot]

51 minutes ago, CharonY said:

Actually no, it a commonly used term in global cycles to describe reservoirs which accumulate and store a given compound (carbon in this case). Any sufficiently large body can act as a carbon sink (regardless of rain) as CO2 exchange with the atmosphere only happens at the surface. If the water is cold, more CO2 is dissolved than released, if it heats up again more CO2 is emitted (ignoring biological fixation for now). As such, deep cold bodies of water can act as a net carbon sink.

The paper by Li et al. (i.e. the one referenced by OP) have found that dissolved inorganic carbon also be sequestered into enodrheic basins. A important mechanism that was observed is that CO2 from soil is being dissolved in the highly saline (and alkaline) water into groundwater aquifers and transported to a terminal lake. The salinity is an important element here as the higher alkalinity allows increased CO2 solubility. They found that source water (i.e. rain snow melt etc.) were basically carbon free, but the groundwater was high in dissolved carbon. That showed that during the transport of water to the basins, they dissolved singificant amount of carbon along the way (i.e. we have mechanism often described as carbon pump into the mentioned carbon sink). Carbon dating experiments showed that the dissolved carbon most of it was fairly young, resulting from soil respiration.

Similar mechanisms have been proposed for other terminal lakes and I found a follow-up paper that escaped my notice earlier: Li et al. Nature Geoscience volume 10, pages501–506 (2017)

Thnaks for the detail, exactly the sort of thing I asked for. +1

 

@mistermack

So now you have two possible mechanisms, both compatible with each other and accepted known Science.