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Author Topic:   Some water measurements for the Flood
NoNukes
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Posts: 9651
From: Central NC USA
Joined: 08-13-2010
Member Rating: 3.1


Message 271 of 276 (730256)
06-26-2014 6:08 AM
Reply to: Message 263 by Faith
06-25-2014 3:10 PM


Re: Scripture
I just took a look through three commentaries at Blue Letter Bible and all of them refer to the firmament as just another word for the heavens or sky, one calling it "poetic."

The text says the firmament is heaven. No problem there.

But then there is a vault of the sky that separates the waters in heaven from the waters on earth. Which means that your look at the commentaries does not resolve the issue.

Then the text indicates that on day four lights separating day and night and indicating the seasons were placed in vault of the sky.


Under a government which imprisons any unjustly, the true place for a just man is also in prison. Thoreau: Civil Disobedience (1846)

I have never met a man so ignorant that I couldn't learn something from him. Galileo Galilei

If there is no struggle, there is no progress. Those who profess to favor freedom, and deprecate agitation, are men who want crops without plowing up the ground, they want rain without thunder and lightning. Frederick Douglass


This message is a reply to:
 Message 263 by Faith, posted 06-25-2014 3:10 PM Faith has not yet responded

    
JonF
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Posts: 3650
Joined: 06-23-2003
Member Rating: 3.6


Message 272 of 276 (730258)
06-26-2014 6:56 AM
Reply to: Message 261 by herebedragons
06-25-2014 1:26 PM


Re: Working with real data
Jon, I was fooling around with your spreadsheet and I tried to figure out what the smallest amount of water that could be plugged in and get a livable temperature. Even at very, very low numbers (10^-24) the temperature still needs to 100C

I'll check, but I think you are taking it outside the valid range. But the calculations are correct. I'll put a more complete answer together, hopefully today.

{ABE} I started on the full explanation, and figured out where you are going wrong. See the first word in cell B12. The pressure under consideration is normal atmospheric pressure (assumed due solely to oxygen and nitrogen and argon and a few trace gasses) *plus* the pressure due to water vapor in the atmosphere. (Actually it could be partly liquid, clouds, above the Earth's surface without affecting the result as long as it's all vapor at the Earth's surface).

The boiling point of water at 15 psi is 100 C. The boiling point of water at (15 + ε ) psi, where ε is small compared to 15 is 100 C within the precision we need here.

And we are looking at pure vapor. Vapor can obviously exist at temperatures lower than 100 C and pressure 15 psi, since humidity exists, but water can also exist; it depends on other factors. But for just vapor no matter what other factors you have to be in the vapor area.

A Pascal (Pa) is 6,895 psi and a Kelvin (K) (not degrees K, just K) is C + 273.15. The red dots are "critical points". The brownish area to the right of the liquid area is "supercritical fluid", both liquid-ish and vapor-ish. The point where all three phases touch is a "triple point" where the three phases are indistinguishable. The little blue X is standard temperature and pressure. If you move right from the blue X you get to the vapor/liquid line at (surprise) 373 K or 100 C.

It's clearer on a pressure-enthalpy diagram with lines of constant temperature, from STEAM P-H DIAGRAM:

The purple-bounded "bell" area is mixed liquid and vapor. To the left of the bell is liquid, to the right of the bell is vapor. The triple point is at the top of the bell Note that the lines of constant temperature are horizontal within the "bell". When a system is mixed water and steam, somewhere along one of those horizontal lines, the percentage of how far along that line it is is the "quality" of the steam. My spreadsheet is calculating the temperature where a line of constant pressure intersects the right edge of the "bell". That's the minimum temperature at which you can have pure vapor. Increase the temperature by the eentsiest bit or more and you must have pure vapor.

Clear as mud?

{ABE2}Cells A12, A13, and A14 should be set to display two figures to the right of the decimal point.

{ABE3} The C to F conversions are correct, multiplication and division take precedence over addition. See the online calculator at http://www.onlineconversion.com/temperature.htm.

Edited by JonF, : No reason given.

Edited by JonF, : No reason given.

Edited by JonF, : No reason given.

Edited by JonF, : No reason given.


This message is a reply to:
 Message 261 by herebedragons, posted 06-25-2014 1:26 PM herebedragons has responded

Replies to this message:
 Message 273 by herebedragons, posted 06-27-2014 7:03 PM JonF has responded

  
herebedragons
Member
Posts: 1328
From: Michigan
Joined: 11-22-2009
Member Rating: 5.9


Message 273 of 276 (730384)
06-27-2014 7:03 PM
Reply to: Message 272 by JonF
06-26-2014 6:56 AM


Re: Working with real data
Clear as mud?

Sure. I understand how phase diagrams work; that is not the issue I was objecting to. What I was saying is that your spread sheet says that for there to be ANY vapor in the atmosphere, the temperature would need to be 100oC. We know that is not the case as there is water vapor in the atmosphere at normal temperatures.

So I am not overly convinced of the “Temperature required to maintain that water as vapor” calculations. I suppose that once water vapor exceeds the saturation point (past equilibrium point), it would require temperatures over 100oC to maintain that high level of water vapor.

The C to F conversions are correct, multiplication and division take precedence over addition.

Yes, they are correct if you are converting absolute temperatures from oC to oF. However , in cell A20, you are converting a change in oC to a change in oF. For this conversion, the formula is [delta]oC * 1.8 = [delta]oF.

For example, a 10oC change in temp converted to oF, say from 10oC to 20oC.

10oC = 50oF
20oC = 68oF

68oF - 50oF = 18oF

So, a 10oC change in temp is an 18oF change, not 50o that you would get if you converted using a standard (oC * 9/5)+32 conversion.

Anyway, I tried a slightly different approach to this problem. I calculated the total volume of the atmosphere and calculated the total amount of water that could be vapor in the atmosphere if the entire troposphere was at 4.25% saturation. At saturation levels greater than 4.25%, water begins to condense and precipitate out.

The volume of the troposphere is about 3.0e20 ft3 so, 4.25% yields 1.28e19 ft3 of water vapor which converts to 1.03e16 ft3 of liquid water. This is enough to cover the surface of the earth to a depth of 2 feet! Using your spreadsheet calculation, this would raise the temperature of the earth 105oC (189oF).

I also found this source The USGS Water Science School that says:

quote:
One estimate of the volume of water in the atmosphere at any one time is about 3,100 cubic miles (mi3) or 12,900 cubic kilometers (km3). That may sound like a lot, but it is only about 0.001 percent of the total Earth's water volume of about 332,500,000 mi3 (1,385,000,000 km3), as shown in the table below. If all of the water in the atmosphere rained down at once, it would only cover the globe to a depth of 2.5 centimeters, about 1 inch.

My calculations above are 23 times the actual estimated volume according to the USGS and still can’t come even close to covering anything close to a mountain.

HBD

Edited by herebedragons, : No reason given.


Whoever calls me ignorant shares my own opinion. Sorrowfully and tacitly I recognize my ignorance, when I consider how much I lack of what my mind in its craving for knowledge is sighing for... I console myself with the consideration that this belongs to our common nature. - Francesco Petrarca

"Nothing is easier than to persuade people who want to be persuaded and already believe." - another Petrarca gem.

Ignorance is a most formidable opponent rivaled only by arrogance; but when the two join forces, one is all but invincible.


This message is a reply to:
 Message 272 by JonF, posted 06-26-2014 6:56 AM JonF has responded

Replies to this message:
 Message 274 by JonF, posted 06-28-2014 11:11 AM herebedragons has responded

  
JonF
Member
Posts: 3650
Joined: 06-23-2003
Member Rating: 3.6


Message 274 of 276 (730465)
06-28-2014 11:11 AM
Reply to: Message 273 by herebedragons
06-27-2014 7:03 PM


Re: Working with real data
I'll go into this more, but my spreadsheet is not saying that it must be 100 C to have any water vapor in the atmosphere. It must be 100C for liquid water to not exist in the atmosphere. The initial condition was solely vapor in the atmosphere.
This message is a reply to:
 Message 273 by herebedragons, posted 06-27-2014 7:03 PM herebedragons has responded

Replies to this message:
 Message 275 by herebedragons, posted 06-28-2014 5:06 PM JonF has responded

  
herebedragons
Member
Posts: 1328
From: Michigan
Joined: 11-22-2009
Member Rating: 5.9


Message 275 of 276 (730508)
06-28-2014 5:06 PM
Reply to: Message 274 by JonF
06-28-2014 11:11 AM


Re: Working with real data
my spreadsheet is not saying that it must be 100 C to have any water vapor in the atmosphere. It must be 100C for liquid water to not exist in the atmosphere.

Yeah, that's what I gathered after figuring how much vapor could actually exist in the atmosphere under normal conditions. When you are calculating the water vapor to produce 60 - 4000 feet of rain, the water vapor that is in the atmosphere initially is insignificant.

I'll go into this more

No need. It makes sense to me.

HBD


Whoever calls me ignorant shares my own opinion. Sorrowfully and tacitly I recognize my ignorance, when I consider how much I lack of what my mind in its craving for knowledge is sighing for... I console myself with the consideration that this belongs to our common nature. - Francesco Petrarca

"Nothing is easier than to persuade people who want to be persuaded and already believe." - another Petrarca gem.

Ignorance is a most formidable opponent rivaled only by arrogance; but when the two join forces, one is all but invincible.


This message is a reply to:
 Message 274 by JonF, posted 06-28-2014 11:11 AM JonF has responded

Replies to this message:
 Message 276 by JonF, posted 06-29-2014 10:54 AM herebedragons has not yet responded

  
JonF
Member
Posts: 3650
Joined: 06-23-2003
Member Rating: 3.6


(1)
Message 276 of 276 (730584)
06-29-2014 10:54 AM
Reply to: Message 275 by herebedragons
06-28-2014 5:06 PM


OK.

You are correct about the delta T conversions, I've fixed it and updated the online copy.


This message is a reply to:
 Message 275 by herebedragons, posted 06-28-2014 5:06 PM herebedragons has not yet responded

  
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