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Author Topic:   Cambrian Explosion and Hydrosphere-Spending Hypothesis
jar
Member
Posts: 33957
From: Texas!!
Joined: 04-20-2004
Member Rating: 2.3


Message 16 of 28 (235288)
08-21-2005 4:44 PM
Reply to: Message 15 by benllinliu
08-21-2005 4:37 PM


Re: Language
I'm glad you came by to visit. However I don't think I'm qualified to add more about your concept than I have so far.


Aslan is not a Tame Lion

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benllinliu
Inactive Member


Message 17 of 28 (255587)
10-30-2005 4:01 AM
Reply to: Message 1 by benllinliu
07-01-2005 10:16 PM


the oxygen is absorbed in the process of some burst of volcano
A old news: a volcano on Salvador bursted out on Oct. 1,2005, it contains many burning lapis.

I think, for the "burning lapis", some oxygen must be absorbed.

I would like some detail analysis for the problem, as the first step, I would like some person provide some detsil for the volcano on Salvador.

I want to know:

1, how much oxygen has been absorbed in a such volcano burst?

2, is there some process to recruit the oxygen? besides from "hydrosphere spending process" according to "hydrosphere spending hypothesis" proposed in the post.

3, if it is true that the oxygen is absorbed with process of valcano burst, why we do not notice such an important topic for lang time?

This message has been edited by benllinliu, 10-30-2005 04:35 AM


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roxrkool
Member (Idle past 266 days)
Posts: 1497
From: Nevada
Joined: 03-23-2003


Message 18 of 28 (255958)
11-01-2005 8:12 AM
Reply to: Message 17 by benllinliu
10-30-2005 4:01 AM


Re: the oxygen is absorbed in the process of some burst of volcano
I'm sorry ben, but I'm not sure what you mean. Are you referring to lapilli, rather than lapis?

As for absorption of oxygen, do you mean oxygen in the form of O2 or any form such as in H2O?


This message is a reply to:
 Message 17 by benllinliu, posted 10-30-2005 4:01 AM benllinliu has replied

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benllinliu
Inactive Member


Message 19 of 28 (255973)
11-01-2005 9:33 AM
Reply to: Message 18 by roxrkool
11-01-2005 8:12 AM


Re: the oxygen is absorbed in the process of some burst of volcano
thank you for your post.

I want to say, some matter was burning surrund the volcano, the oxygen would be absorbed from atmosphere with the substance from inner of the earth.

I do not understand the meaning of the word "lap???". As my understanding, it probably mean "hot stone" arround the volcano.

This message has been edited by benllinliu, 11-01-2005 09:40 AM


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benllinliu
Inactive Member


Message 20 of 28 (256101)
11-01-2005 8:37 PM


the topic is also dicussed on science forum
the topic is also dicussed on science forum these days.

http://www.thescienceforum.com/viewtopic.php?t=625&start=15


Replies to this message:
 Message 21 by bernd, posted 11-05-2005 5:35 PM benllinliu has replied

  
bernd
Member (Idle past 3258 days)
Posts: 95
From: Munich,Germany
Joined: 07-10-2005


Message 21 of 28 (257118)
11-05-2005 5:35 PM
Reply to: Message 20 by benllinliu
11-01-2005 8:37 PM


Re: the topic is also dicussed on science forum
Hello benllinliu,

I have some remarks concerning the “hydrosphere spending hypothesis”, specially about the supposed mechanism of decomposition of methane in the exosphere and the escape of the resulting hydrogen atoms into outer space. In the link you provided[1], which covers the hypothesis in some detail, an alternative to this mechanism is described and dismissed as “not validated strictly”:


Bates et al in 1950 proposed that the methane would be oxidized gradually by hydroxyl[10]. However, the hydroxyl oxidizing process was not validated strictly, and academic cycle often considered that whereabouts of the methane in the atmosphere is still a misty with necessary of further research[11], though the explanation of the methane oxidized gradually by hydroxyl is popular in the world now

Please note, the conclusion, that more research is needed, is based on an article from 1980. When we compare the quoted paragraph with the following survey from 2001 [2], which sums up the current knowledge about the methane cycle - including a table (4.2) detailing the methane budget based on three relatively recent studies (1991, 1997,1998) - we find that methane loss in the atmosphere is mainly caused by its reaction with OH in the troposphere, expressed by:


OH + CH4 -> CH3 + H2O

Minor losses are reported for the stratosphere by reactions with OH, Cl, and O(1D). Losses in the exosphere are not mentioned.

Any comments?

-Bernd


References

[1] http://www.thescienceforum.com/viewtopic.php?t=625&start=3
[2] http://www.grida.no/climate/ipcc_tar/wg1/134.htm#4211


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benllinliu
Inactive Member


Message 22 of 28 (257141)
11-05-2005 7:08 PM
Reply to: Message 21 by bernd
11-05-2005 5:35 PM


Re: the topic is also dicussed on science forum
I am glad for reading your expert post.

In general, as I considered, the methane prodused from biosphere is much more than 600 M (600,000,000)tons each year, so some further and rapid decomposing methane channel must be introduced.

I shall further read your articles refered, then give another post in detail.


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benllinliu
Inactive Member


Message 23 of 28 (257223)
11-06-2005 2:27 AM
Reply to: Message 21 by bernd
11-05-2005 5:35 PM


the evidence of methane being decomposed in upper atmosphere
Thank you for your post.

I have read the article [2], It said first:

"
“Methane’s globally averaged atmospheric surface abundance in 1998 was 1,745 ppb (see Figure 4.1), corresponding to a total burden of about 4,850 Tg(CH4). The uncertainty in the burden is small (±5%) because the spatial and temporal distributions of tropospheric and stratospheric CH4 have been determined by extensive high-precision measurements and the tropospheric variability is relatively small. For example, the Northern Hemisphere CH4 abundances average about 5% higher than those in the Southern Hemisphere. Seasonal variations, with a minimum in late summer, are observed with peak-to-peak amplitudes of about 2% at mid-latitudes. The average vertical gradient in the troposphere is negligible, ***but CH4 abundances in the stratosphere decrease rapidly with altitude, *** e.g., to 1,400 ppb at 30 km altitude in the tropics and to 500 ppb at 30 km in high latitude northern winter.
"

I think, follow remark
"
***CH4 abundances in the stratosphere decrease rapidly with altitude, *** e.g., to 1,400 ppb at 30 km altitude in the tropics and to 500 ppb at 30 km in high latitude northern winter.
”

is very important, and it should be considered carefully.

There are two possible cause and corresponding treating manner:

1, the methane cannot get up to the upper atmosphere at all, so its abundance is fewer than that in the troposphere naturally, and this mean that the methane loss process in upper atmosphere should also fewer than that in troposphere, and it can be neglected at last;

2, the methane can get up to the upper atmosphere from the troposphere, and it is decomposed quickly in the upper atmosphere, so its abundance in the upper atmosphere is fewer than that in troposphere. In this case, the methane loss process in upper atmosphere should be an important channel for the methane loss.

I would like to choose the second one since no reason to choose the first one. I think, so much as, the fact of that “1,400 ppb at 30 km altitude in the tropics and to 500 ppb at 30 km in high latitude northern winter” , can be considered as an evidence for that the methane can be destroyed quickly in upper atmosphere: the gas( containing oxygen,nitrogen etc. ) is with ordinary abundance of methane when it just get up to upper atmosphere in the tropic, then the methane is decomposed by sunlight, so its abundance get fewer and fewer before the gas return to troposphere in high latitude. This means that a lot of methane is decomposed in upper atmosphere, and all related detail should be reconsidered!

As I know from a book named “carbon cycle of the earth system”(by Banqin Chen et,al, in Chinese) the pure carbon equivalence of total organic matter produced in the world each year is about 60,000 Tg(C)/yr, contains about 21,000 Tg(C)/yr from forest, 3,200 Tg(C)/yr from wetland, 6,800 Tg(C)/yr. I think, the total methane gross per year, 600 Tg(CH4)/yr, is only about 1% of organic matter to change as methane and other 99% will be changed to carbon dioxide, this seems too few to the total for the methane. Perhaps, it is wetland that the gross of the methane should be about 600 Tg(CH4)/yr, where the carbon equivalence of organic matter produced is about 3,200 Tg(C)/yr, if 20% gross of the organic matter turns into methane.

At last, instead 1% of organic matter turn into methane, we would probably validate within next 10 years that about 10% of organic matter produced every year in the earth turn into methane which means other way for the loss of methane. If so, the research work will enriches our knowledge on our earth.

This is a large and interesting research work, a lots of details should be deliberated. I would like you and other people to take part in the work, combine for the possible discovery.

This message has been edited by benllinliu, 11-06-2005 03:06 AM

This message has been edited by benllinliu, 01-29-2006 09:22 AM


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 Message 21 by bernd, posted 11-05-2005 5:35 PM bernd has replied

Replies to this message:
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benllinliu
Inactive Member


Message 24 of 28 (257228)
11-06-2005 2:54 AM
Reply to: Message 21 by bernd
11-05-2005 5:35 PM


Re: the topic is also dicussed on science forum
Some further reply will be made.

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bernd
Member (Idle past 3258 days)
Posts: 95
From: Munich,Germany
Joined: 07-10-2005


Message 25 of 28 (257267)
11-06-2005 9:57 AM
Reply to: Message 23 by benllinliu
11-06-2005 2:27 AM


Re: the evidence of methane being decomposed in upper atmosphere
Hello benllinliu,

Thank you for your interesting answer. First a question, I‘m not sure what you exactly mean with upper atmosphere, the layers above the mesopause? Please clarify! Besides that, I have some additional remarks.


  • When I understand your model for hydrogen escape correctly, you are assuming temperatures of 1000° K of the hydrogen atom (deduced from this post [1] ). I agree that at this temperature a considerable part of the atoms would escape into outer space. But a quick look at this link[2] shows that such temperatures are only reached in the thermosphere at about 300 km altitude, temperatures in the stratosphere are much lower, less than 300 °K. In other words to defend your hypothesized mechanism you would have to demonstrate a substantial methane flux from the stratosphere at least to the thermosphere.

  • When we accept the budget data that was presented in [3], only 20-40 Tg/yr are candidates for the above mentioned flux. Could this amount produce the effect you are predicting, that is a reduction of the original mass of the ocean by a factor of 20? Let‘s do a quick calculation. When we assume that all methane is generated by methane producing bacteria and that life on earth exists for less than 4*109 years, when we further assume that to produce one molecule methane we need one water molecule, then we can conclude that we loose about 4*109 * 40 Tg methane, which would roughly correspondent to 1.6 * 1011 Tg water. The present day ocean on the other hand contains 1.4*1012 Tg water.

  • When we further consider that your model assumes that the first land masses appeared only in the Cambrium, we have to reduce the estimated methane loss even more, with an ocean to atmosphere flux of 0.4 Tg (see [4] ), we get 3.5*109 *0.4 Tg + 0.5*109*40 Tg, that is 2.14 * 1010 Tg, which amounts to 1.5 % of the mass of the current ocean.


-Bernd


References
[1] http://www.thescienceforum.com/viewtopic.php?t=625&start=19
[2] http://spacescience.nrl.navy.mil/introupatmsci.html
[3] http://www.grida.no/climate/ipcc_tar/wg1/134.htm#4211
[4] http://saga.pmel.noaa.gov/gas_program.html

This message has been edited by bernd, 06-Nov-2005 04:46 PM

This message has been edited by bernd, 06-Nov-2005 04:50 PM


This message is a reply to:
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benllinliu
Inactive Member


Message 26 of 28 (257564)
11-07-2005 6:31 PM
Reply to: Message 25 by bernd
11-06-2005 9:57 AM


the discussion on the process of hydrosphere spending
Dear Bernd:

Thank you for your earnest post, I shall give a simple reply first.

You wrote:
"First a question, I‘m not sure what you exactly mean with upper atmosphere, the layers above the mesopause? "

In general, the words “upper atmosphere” in my posts means the layers above the troposphere.

You wrote:
"When I understand your model for hydrogen escape correctly, you are assuming temperatures of 1000° K of the hydrogen atom (deduced from this post [1] ). I agree that at this temperature a considerable part of the atoms would escape into outer space. But a quick look at this link[2] shows that such temperatures are only reached in the thermosphere at about 300 km altitude, temperatures in the stratosphere are much lower, less than 300 K. In other words to defend your hypothesized mechanism you would have to demonstrate a substantial methane flux from the stratosphere at least to the thermosphere."

Before the escape process of the hydrogen according to the “hydrosphere spending hypothesis”is discussed, I would like to refer the atmospheric concept of “uneven layer”, with which I understand well in Chinese, however, I cannot confirm the corresponding term in English for the concept. It is said by the concept of “uneven layer”, which contains thermosphere and mesosphere, the rate of hydrogen in the layer is much higher than that in troposphere.

I would like to point out, the escape process of the hydrogen contains several steps, and it needs not the methane to reach thermosphere where the hydrogen escapes.

As I considered, as the first step, the methane reaches the stratosphere in the night, when there is no sunlight, so temperature of stratosphere would drop, and the boundary between the troposphere and stratosphere would become faint in some degree. The methane also can be considered to climb up to upper atmosphere in day, however, as we considered, it should occur mainly in night, and, as referred in previous post, it should climb mainly at the tropics.

As the second step, the methane will be decomposed. It is obviously, the methane should decomposed in the day with sunlight. And, I suppose, the decomposing process would occur around ozonosphere, where is not very high.

The decomposed carbon from the methane will combine with oxygen to form dioxide carbon, which remains in the atmosphere, then it returns probably to biosphere again. As for the decomposed hydrogen atoms, some of them would get higher and higher to thermosphere in the “uneven layer”. Certainly, some of them would combine with oxygen to form water molecules, some of which would return to hydrosphere, and other would also be decomposed to hydrogen atoms.

As I considered, the escape process of the hydrogen atoms should take place in thermosphere, where the trmpersture is higher than of 1000°K . It would be worthy to point out in some detail, the escape of the hydrogen can not disperse at all direction(s) sccording to "hydrosphere spending hypothesis". It cannot go to the sun, because of the pressure of the sunlight, it cannot also go out in the night, because there is no sunlight, so there is no thermal dynamics. It cannot also go out on the morning. I would like to point out, the hydrogen only could escape out with setting sun!

The escape process is taken place in thermosphere, if the altitude is about 300-1500-km, and if the latitude is around of the earth about from 30° to +30°, which corresponds to 7000-km length. Furthermore, combining the altitude and latitude, it means an area of the escape section:

(1500-300) * 7000= 1200 * 7000 = 9,400,000 (km*km)

This is would be a certain and large channel. If flux of escaping hydrogen todays is about 10 tons per second (about 300 Tg(h)/yr, corresponding to 3 cubic km water ) with a velocity of 10,000 m/s, the density of escaping hydrogen can be reckoned as follows:

10,000,000g/100,000,000 cubic km, =0.1g/cubic km.

the beam of escaping hydrogen is like a tippet for the earth, and it should be observed with modern space science, though it is quite subtle.

You wrote:
"When we accept the budget data that was presented in [3], only 20-40 Tg/yr are candidates for the above mentioned flux. Could this amount produce the effect you are predicting, that is a reduction of the original mass of the ocean by a factor of 20? Let‘s do a quick calculation. When we assume that all methane is generated by methane producing bacteria and that life on earth exists for less than 4*109 years, when we further assume that to produce one molecule methane we need one water molecule, then we can conclude that we loose about 4*109 * 40 Tg methane, which would roughly correspondent to 1.6 * 1011 Tg water. The present day ocean on the other hand contains 1.4*1012 Tg water.

When we further consider that your model assumes that the first land masses appeared only in the Cambrium, we have to reduce the estimated methane loss even more, with an ocean to atmosphere flux of 0.4 Tg (see [4] ), we get 3.5*109 *0.4 Tg + 0.5*109*40 Tg, that is 2.14 * 1010 Tg, which amounts to 1.5 % of the mass of the current ocean. "

As I considered, the budget data and some other data should deliberated in future. However, I would like to point out, the rate of the hydrosphere spending is changing in the geological ages, which should be positive corresponding to the active degree of the biosphere. I guess, the rate of the hydrosphere spending in Carboniferous would be 4 – 7 times of that now, and the rate of the hydrosphere spending in Jurassic would be 6 – 9 times of that now, when the oxygen, methane in the atmosphere is also several times more than that now.

Thank you for your referances.

Some further details will be discussed in future.

Benlin Liu

This message has been edited by benllinliu, 11-08-2005 05:16 AM


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benllinliu
Inactive Member


Message 27 of 28 (290825)
02-27-2006 8:51 AM


important discovery: plant produce methane
http://www.eurekalert.org/pub_releases/2006-01/m-tfm011006.php

original title: The forgotten methane source

In the last few years, more and more research has focused on the biosphere; particularly, on how gases which influence the climate are exchanged between the biosphere and atmosphere. Researchers from the Max Planck Institute for Nuclear Physics have now carefully analysed which organic gases are emitted from plants. They made the surprising discovery that plants release methane, a greenhouse gas - and this goes against all previous assumptions. Equally surprising was that methane formation is not hindered by the presence of oxygen. This discovery is important not just for plant researchers but also for understanding the connection between global warming and increased greenhouse gas production (Nature, January 12, 2006).

Methane is the greenhouse gas which has the second greatest effect on climate, after carbon dioxide. The concentration of methane in the atmosphere has almost tripled in the last 150 years. Methane is best known as natural gas, currently an important energy source. Nonetheless, only part of the methane uptake in the atmosphere is due to industrial activities connected to energy production and use. More important for the increase of methane in the atmosphere is the increase in so-called "biogenic" sources, e.g., rice cultivation or domestic ruminants related to the rise in the world's population. Nowadays, methane in the atmosphere in fact is largely of biogenic origin.

Until now, it has been assumed that biogenic methane is formed anaerobically, that is, via micro-organisms and in the absence of oxygen. In this way, acetate or hydrogen and carbon dioxide are transformed into methane; they themselves are created in the anaerobic decomposition of organic materials. The largest anoxic sources of methane are wetlands and rice fields, as well as the digestion of ruminants and termites, waste disposal sites, and the gas produced by sewage treatment plants. According to previous estimates, these sources make up two-thirds of the 600 million tonnes worldwide annual methane production.

Scientists from the Max Planck Institute for Nuclear Physics have now discovered that plants themselves produce methane and emit it into the atmosphere, even in completely normal, oxygen-rich surroundings. The researchers made the surprising discovery during an investigation of which gases are emitted by dead and fresh leaves. Then, in the laboratory and in the wild, the scientists looked at the release of gases from living plants like maize and ryegrass (see image 1). In this investigation, it turned out that living plants let out some 10 to 1000 times more methane than dead plant material. The researchers then were able to show that the rate of methane production grew drastically when the plants were exposed to the sun.

Although the scientists have some first indications, it is still unclear what processes are responsible for the formation of methane in plants. The researchers from Heidelberg assume that there is an unknown, hidden reaction mechanism, which current knowledge about plants cannot explain - in other words, a new area of research for biochemistry and plant physiology.

In terms of total amount of production worldwide, the scientists' first guesses are between 60 and 240 million tonnes of methane per year. That means that about 10 to 30 percent of present annual methane production comes from plants. The largest portion of that - about two-thirds - originates from tropical areas, because that is where the most biomass is located. The evidence of direct methane emissions from plants also explains the unexpectedly high methane concentrations over tropical forests, measured only recently via satellite by a research group from the University of Heidelberg.

But why would such a seemingly obvious discovery only come about now, 20 years after hundreds of scientists around the globe started investigating the global methane cycle? "Methane could not really be created that way," says Dr. Frank Keppler. "Until now all the textbooks have said that biogenic methane can only be produced in the absence of oxygen. For that simple reason, nobody looked closely at this."

The fact is that, in order to determine the quantity of emissions, scientists indeed have to make very careful measurements. The researchers from Heidelberg conducted most of their experiments in methane-free air, in order to factor out the high natural background of methane. Furthermore they used isotope analysis to show beyond doubt that this was an undiscovered process of methane production. By "looking closely" - despite established opinion - they made a discovery that will require textbooks to have their passages about methane production rewritten.

Following up on this discovery, the scientists now will continue laboratory work, as well as field and remote sensing studies, to better quantify the strength of these methane emissions. A related exciting question is which role the biosphere has played in methane production in the history of the earth, and what kind of influence rising global temperatures and carbon dioxide concentration have on the production of methane from plants. Answers to these questions are important for understanding the feedback mechanisms between climate change and greenhouse gas production.


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benllinliu
Inactive Member


Message 28 of 28 (290830)
02-27-2006 9:00 AM
Reply to: Message 27 by benllinliu
02-27-2006 8:51 AM


Re: important discovery: plant produce methane
I think, the new source means new sink to be needed.

As I considered, the old source of the methane should be much more than 600 million tons per year.

And, the methane in the atmosphere has been about 1700-1800 ppb for long time, is not increased for long time. I have find some date 25 years ago, and I shall show these work.


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