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Post by Andrew on Jan 28, 2014 7:30:11 GMT
Since the latent heat discussion is rolling endlessly onwards and has been going for 7 months and the same link that was provided 7 months ago has been raised yet again to say freezing causes temperature to be higher in orchards i wrote to the University of Florida Institute of Food and Agricultural Sciences to ask them to clarify what they are talking about. ------------------------------- Re: edis.ifas.ufl.edu/ch182Microsprinkler Irrigation for Cold Protection of Florida Citrus1 L. R. Parsons and B. J. Boman Hi, This article appears to be making the claim that when water freezes - as temperatures fall in an orchard - the freezing process is somehow able to raise temperatures in the orchard. Freezing cannot do that. All freezing can do is maintain the temperature of the ice and water mixture at 0C where when the water was 0.0001C the water provided more heating for the orchard than the freezing mixture can do. However if a drop of water is on a delicate part of a plant and ice is forming, the plant is protected becaus without latent heat the cooling part would immediately become less than 0C once 0C was reached during cooling. Latent heat therefore gives an opportunity for heating of the plant to be maintained at 0C until all of the water has frozen, where because of the latent heat of freezing, it takes a considerable extra amount of cooling before the ice is fully formed and sub zero temperatures are possible. I have been discussing these issues with a North Dakota farmer and i have been totally unable to explain to him the processes involved, so any help you can give me by clarifying the meaning of that article would be greatly appreciated indeed. Best Regards Andrew
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Post by Andrew on Jan 28, 2014 13:50:51 GMT
Got a reply back to say both of the authors of the paper have been contacted for a response
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I've contacted both Dr. Parsons and Dr. Boman regarding your question hopefully you hear a response back from one or both of them shortly. Please let me know if I can do anything else. Best regards,
UF/IFAS Citrus Research and Education Center 700 Experiment Station Rd. Lake Alfred, FL 33850 (863) 956-5890
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Post by Andrew on Jan 29, 2014 5:18:08 GMT
I am conscious that the authors of this paper might be very resistant to what i am saying, particularly if their thinking has been part of their professional presentations over many years where almost certainly along the way somebody has challenged what they are saying.
To help clarify what I am talking about I sent the following today.
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Thanks for passing on my message to the authors of the document.
To help them with the point i am raising I notice their text reads:
>>"Heat of fusion >>The heat that is released when liquid water freezes to solid ice is called the heat of fusion"
Water does not have a heat of fusion but rather has a Latent heat of fusion. Fusion actually means melting, so really we are talking here about the positive amount of energy involved in the latent heat of freezing. However this hidden heat is not able to be released externally from the ice other than via an internal heat transfer which keeps the water and ice mixture at 32F, which can then in turn provide heating for say a plant at 31F. Therefore the text that reads:
>>The heat that is released when liquid water freezes to solid ice is called the heat of fusion
Is better written something like the following so that the text is unambiguous as to what the words mean.
"When an amount of water begins freezing there is a large amount of hidden heating available to maintain the temperature of the mixture at 0C for much longer than would be possible if there was no hidden heat available. This hidden heat is called the latent heat of freezing. (When water melts the large amount of additional hidden heating required to melt ice is called the latent heat of fusion)"
Unfortunately there are no easy ways to explain this topic in a few words so that confusions do not arise.
Best Regards
Andrew
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Post by icefisher on Feb 1, 2014 20:12:31 GMT
I am conscious that the authors of this paper might be very resistant to what i am saying, particularly if their thinking has been part of their professional presentations over many years where almost certainly along the way somebody has challenged what they are saying. To help clarify what I am talking about I sent the following today. --------------------------------------- Thanks for passing on my message to the authors of the document. To help them with the point i am raising I notice their text reads: >>"Heat of fusion >>The heat that is released when liquid water freezes to solid ice is called the heat of fusion" Water does not have a heat of fusion but rather has a Latent heat of fusion. Fusion actually means melting, so really we are talking here about the positive amount of energy involved in the latent heat of freezing. However this hidden heat is not able to be released externally from the ice other than via an internal heat transfer which keeps the water and ice mixture at 32F, which can then in turn provide heating for say a plant at 31F. Therefore the text that reads: >>The heat that is released when liquid water freezes to solid ice is called the heat of fusion Is better written something like the following so that the text is unambiguous as to what the words mean. "When an amount of water begins freezing there is a large amount of hidden heating available to maintain the temperature of the mixture at 0C for much longer than would be possible if there was no hidden heat available. This hidden heat is called the latent heat of freezing. (When water melts the large amount of additional hidden heating required to melt ice is called the latent heat of fusion)" Unfortunately there are no easy ways to explain this topic in a few words so that confusions do not arise. Best Regards Andrew -------------------------------- Mental masturbation!!! Pure and simple!! You are making nondistinctions here, basically brow beating folks simply because you imagine confusion as if the confusion you sow is any less confusing. hyperphysics.phy-astr.gsu.edu/hbase/thermo/phase2.htmlheat of fusion is commonly used as can be seen as referenced above. Your distiction of "latent heat of fusion" is actually a redundancy and adds nothing whatsoever to the conversation. Its like a pleonasm where when you remove the word "latent" you have not changed anything so why apply the word? Maybe you can browbeat somebody into this kind of redundancy but its you mentally masturbating yourself, nothing more. "However this hidden heat is not able to be released externally from the ice other than via an internal heat transfer"Here it is not clear if you have any scientific proof of a unique physical event. Does an internal transfer of energy actually take place separate from the release of heat to the environment? It seems to me that logically for that to occur it must involve supercooling. If so, then your argument it does not warm the water goes out the window Andrew! If the surface freezes first then the release of heat will be to the environment and it will become sensible. If not the ice could not freeze as the release of latent heat cannot transfer to the warmer adjacent water. The heat will be coming from the water through the ice to the environment and the heat of fusion is not being deposited internally. If the water freezes from the inside first then the water must be supercooled or the water could not cool internally to freeze. So in summary for the latent heat to be deposited internally the water has to be supercooled and you become wrong again in claiming the temperature is maintained with no change. Your argument seems illogical. Since on the surface its illogical it would be nice if you actually provided these people, and us, with some reference material that clearly shows your process is logical.
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Post by Andrew on Feb 1, 2014 20:17:24 GMT
I am conscious that the authors of this paper might be very resistant to what i am saying, particularly if their thinking has been part of their professional presentations over many years where almost certainly along the way somebody has challenged what they are saying. To help clarify what I am talking about I sent the following today. --------------------------------------- Thanks for passing on my message to the authors of the document. To help them with the point i am raising I notice their text reads: >>"Heat of fusion >>The heat that is released when liquid water freezes to solid ice is called the heat of fusion" Water does not have a heat of fusion but rather has a Latent heat of fusion. Fusion actually means melting, so really we are talking here about the positive amount of energy involved in the latent heat of freezing. However this hidden heat is not able to be released externally from the ice other than via an internal heat transfer which keeps the water and ice mixture at 32F, which can then in turn provide heating for say a plant at 31F. Therefore the text that reads: >>The heat that is released when liquid water freezes to solid ice is called the heat of fusion Is better written something like the following so that the text is unambiguous as to what the words mean. "When an amount of water begins freezing there is a large amount of hidden heating available to maintain the temperature of the mixture at 0C for much longer than would be possible if there was no hidden heat available. This hidden heat is called the latent heat of freezing. (When water melts the large amount of additional hidden heating required to melt ice is called the latent heat of fusion)" Unfortunately there are no easy ways to explain this topic in a few words so that confusions do not arise. Best Regards Andrew -------------------------------- Mental masturbation!!! Pure and simple!! You are making nondistinctions here, basically brow beating folks simply because you imagine confusion as if the confusion you sow is any less confusing. hyperphysics.phy-astr.gsu.edu/hbase/thermo/phase2.htmlheat of fusion is commonly used as can be seen as referenced above. Your distiction of "latent heat of fusion" is actually a redundancy and adds nothing whatsoever to the conversation. Its like a pleonasm where when you remove the word "latent" you have not changed anything so why apply the word? Maybe you can browbeat somebody into this kind of redundancy but its you mentally masturbating yourself, nothing more. The word latent makes a massive difference. If water released all of the latent heat of freezing once it reached 0C it would warm to 80C!
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Post by sigurdur on Feb 1, 2014 20:18:09 GMT
Icefisher: Andrew has a temporary mental block. No sense beating a dead horse, nor picking up a shovel to dig the grave deeper.
He is a bright feller, give him some time to grasp the actual concept. He has a bad case of Skeptical Science Syndrome right now, but he is too smart to not get over that illness.
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Post by Andrew on Feb 1, 2014 20:22:10 GMT
Icefisher: Andrew has a temporary mental block. No sense beating a dead horse, nor picking up a shovel to dig the grave deeper. He is a bright feller, give him some time to grasp the actual concept. He has a bad case of Skeptical Science Syndrome right now, but he is too smart to not get over that illness. Idiot! What kind of moron thinks if you freeze water it creates higher temperatures in a previously cooling orchard?
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Post by sigurdur on Feb 1, 2014 20:26:30 GMT
Andrew: I and others have tried to demonstrate real world observations to you.
Enough of the name calling.
IF you can't be a gentleman...go somewhere else.
Thank you.
I come to this board to share thoughts/papers with folks who can think out of the box of AGW....I don't come to be insulted.
I would hope you share my sentiment.
Thank you.
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Post by Andrew on Feb 1, 2014 20:46:21 GMT
Andrew: I and others have tried to demonstrate real world observations to you. Enough of the name calling. IF you can't be a gentleman...go somewhere else. Thank you. I come to this board to share thoughts/papers with folks who can think out of the box of AGW....I don't come to be insulted. I would hope you share my sentiment. Thank you. I have tried to explain to you dozens of times in dozens of ways why you are wrong. Your position is totally illogical. Freezing water produces fewer btu's per second than warmer water, so it cannot possibly heat the cooling orchard to a higher temperature than the water can do. All you ever do is quote latent heat theory but you never interact with my explanation of why you are wrong. You have to do more than just get a book out and quote passages about latent heat Why do you refuse to interact with my points? Freezing water produces fewer btu's per second than warmer water. If the temps are falling with more BTus per second there is no way on gods earth that fewer btus for all of eternity can create higher temperatures. Are you ever going to interact with that text??
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Post by sigurdur on Feb 1, 2014 21:00:29 GMT
Andrew: The phase change of water to ice releases MORE BTU per second than cooling water. That is why it can HALT the temp drop, which cooling water can't do.
It not only halts the temp drop on a plant, the phase change can warm the orchard as demonstrated in Florida.
This works worldwide by the way. Should even work in Finland as physics doesn't recognize boundaries.
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Post by Andrew on Feb 1, 2014 21:06:48 GMT
Andrew: The phase change of water to ice releases MORE BTU per second than cooling water. That is where you are going wrong and it should be easy for you to check that. Hotter substances have a greater heating ability than colder substances. A hotter furnace produces more BTUS than when it is colder. The total phase change releases an enormous number of BTUS but they are released more slowly than from the warmer water.
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Post by sigurdur on Feb 1, 2014 21:47:27 GMT
Andrew: The phase change is actually very rapid.
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Post by Andrew on Feb 1, 2014 21:57:39 GMT
Andrew: The phase change is actually very rapid. Sorry, you are wrong again, it is the slowness of the phase change at the constant temperature that protects the plants. Water does not freeze rapidly and neither does it melt rapidly because of the required latent heat transfer.
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Post by icefisher on Feb 1, 2014 21:58:35 GMT
Freezing water produces fewer btu's per second than warmer water. If the temps are fallign with more BTus per second there is no way on gods earth that fewer btus for all of eternity can create higher temperatures. Are you ever going to interact with that text?? Seems to me the goal posts have moved from no external release of heat from the release of the heat of fusion to a completely different proposition that the rate of external release of the heat of fusion is less than warmer water. Does that mean you have conceded that the heat of fusion is released externally? Nobody ever said the rate of heat release of the heat of fusion is greater than the rate of heat release of warmer water. The entire discussion started with Numeruno and yourself Andrew disputing that the energy of the heat of fusion is ever released externally. I have pointed out repeatedly that you have never owned up to this despite your consistent attempts to move past it. As to the irrigation strategy: The reason why it works is the combined BTUs from the freezing water and the water spray is what warms the orchard. 1C water has a slightly higher heat release rate than freezing water but the freezing slows the cooling, and dripping to the ground, and seepage of the water into the ground and its more effective than the airborne spray and drip because of lesser evaporation. As a result more BTUs are are available for warming the air than if freezing did not occur. So if you do not want to move the goal posts stop trying to dissect the process and make unnetted comparisons between pieces of the irrigation strategy.
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Post by sigurdur on Feb 1, 2014 22:03:55 GMT
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