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Post by icefisher on Oct 17, 2016 6:02:57 GMT
Perhaps you can clarify today what your position is on latent heat, and the rate of BTU release, where you told me at the beginning of this thread when water freezes the higher release rate of the BTU's is what causes the temperature to halt during the phase change? explain what andrew? seems quite clear to me that the rate of release is as variable as need be to 1) to prevent the water/ice from cooling and 2) slow enough so that the ice that is freezing does not melt. so the actual release rate you would estimate based upon the various convective and radiant heat transfer rates depending upon temperatures of the environment and its chemical composition and wind speed along with a few other variables such as orientation and texture of surfaces, nearby structures or other plants, quantity of water applied etc. so one should not have a single position as you have asked for
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Post by sigurdur on Oct 20, 2016 14:13:06 GMT
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Post by missouriboy on Oct 20, 2016 18:48:46 GMT
Thank you Sig. I've never visit this web site before, but I'll be back. You suppose that anybody has taken a shot at estimating what the totality of such vents, over time, matter to the atmosphere. Are concentrations a flyspeck in an dinosaur pile ... or are they worse than that?
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Post by nautonnier on Oct 20, 2016 22:59:58 GMT
The kinetic energy of the molecules being lost/transferred due to collision is 'standard' conduction. The vibrational/rotational energy of the molecule is less simple to explain. All the papers state that it is 'released' on phase change on condensation or freezing but none explain that release at the molecular level. Yes it is released as a jet of steam at 100C will do far more damage than a jet of dry air at 100C, and sprayed apples do not freeze I just do not understand why you are suggesting there is something mysterious about water vapour having a terrible burning capacity when contacting colder human skin when it undergoes the phase change compared to a similar gas of similar heat capacity of the same temperature that does not undergo a phase change. Nearly all of your posts are alluding to something incredibly remarkable about the release of latent heat during the water phase change. Likewise this comment about sprayed apples not freezing. What you are doing is a bit weird and it is beyond me to make sense of what you doing. Well I know you will not believe anything I say so here are two of many descriptions of the release of latent heat of condensation. www.reference.com/health/steam-burns-severe-66303cc5b07d6a6d" A steam burn can cause more damage than boiling water of the same temperature. When boiling water makes contact with the skin, it decreases in temperature but does not undergo a phase change like steam, states the University of British Columbia. Steam decreases in temperature as it hits the skin, condensing into liquid and undergoing a phase change. This change releases energy quickly enough to damage skin cells more severely than boiling water, even when the water is the same temperature as the steam."c21.phas.ubc.ca/article/steam-burns "We will compare the amount of thermal energy transferred to your skin for the case of steam at 100 deg C versus an equivalent mass of boiling water at 100 degC.
When boiling water at intial temperature Ti = 100 degC hits your skin and cools to a final temperature of Tf = 25 degC the amount of energy, Q, transferred from the water to your skin is given by
$ Q = Mc\Delta T $
where M is the mass of the water, c = 4190 J kg-1K-1 is the specific heat of water 1, and $ \Delta T = T_{f} - T_{i} $. Taking M = 1 g the total heat transfer to your skin would be 314 J.
When 1 g of steam hits your skin at Ti = 100 degC it must first condense to liquid water undergoing a phase change before it will drop in temperature. The thermal energy released from the steam to your skin when condensing is given by M Lv, where Lv is the heat of vaporization and is 22.6 * 105 J kg-1 for water 1 and M is the mass of the steam in contact with your skin. For 1g of steam this gives M Lv = 2260 J. Once the steam has turned to liquid water additional thermal energy is transferred to the skin when the condensed water goes from Ti = 100 degC to Tf = 25 degC as calculated above. This means the steam lost an additional 2260 J of energy. This heat released due to condensation partially accounts for the severity of steam burns."
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Post by nonentropic on Oct 21, 2016 2:49:19 GMT
Naut please stop, for your sanity.
From what you have posted I think you have an engineering background and this stuff is central to your thinking but not to all on this site.
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Post by Andrew on Oct 21, 2016 6:58:12 GMT
I just do not understand why you are suggesting there is something mysterious about water vapour having a terrible burning capacity when contacting colder human skin when it undergoes the phase change compared to a similar gas of similar heat capacity of the same temperature that does not undergo a phase change. Nearly all of your posts are alluding to something incredibly remarkable about the release of latent heat during the water phase change. Likewise this comment about sprayed apples not freezing. What you are doing is a bit weird and it is beyond me to make sense of what you doing. Well I know you will not believe anything I say so here are two of many descriptions of the release of latent heat of condensation. www.reference.com/health/steam-burns-severe-66303cc5b07d6a6d" A steam burn can cause more damage than boiling water of the same temperature. When boiling water makes contact with the skin, it decreases in temperature but does not undergo a phase change like steam, states the University of British Columbia. Steam decreases in temperature as it hits the skin, condensing into liquid and undergoing a phase change. This change releases energy quickly enough to damage skin cells more severely than boiling water, even when the water is the same temperature as the steam."c21.phas.ubc.ca/article/steam-burns "We will compare the amount of thermal energy transferred to your skin for the case of steam at 100 deg C versus an equivalent mass of boiling water at 100 degC.
When boiling water at intial temperature Ti = 100 degC hits your skin and cools to a final temperature of Tf = 25 degC the amount of energy, Q, transferred from the water to your skin is given by
$ Q = Mc\Delta T $
where M is the mass of the water, c = 4190 J kg-1K-1 is the specific heat of water 1, and $ \Delta T = T_{f} - T_{i} $. Taking M = 1 g the total heat transfer to your skin would be 314 J.
When 1 g of steam hits your skin at Ti = 100 degC it must first condense to liquid water undergoing a phase change before it will drop in temperature. The thermal energy released from the steam to your skin when condensing is given by M Lv, where Lv is the heat of vaporization and is 22.6 * 105 J kg-1 for water 1 and M is the mass of the steam in contact with your skin. For 1g of steam this gives M Lv = 2260 J. Once the steam has turned to liquid water additional thermal energy is transferred to the skin when the condensed water goes from Ti = 100 degC to Tf = 25 degC as calculated above. This means the steam lost an additional 2260 J of energy. This heat released due to condensation partially accounts for the severity of steam burns."If you and Nonentropic are unable to read we might as well just end right here. I have neither the time or the energy to read your mind to find out what that text is supposed to be telling me where there is nothing mysterious about steam burning human skin whatsoever. Likewise barycenters where there is nothing strange about what Svalgaard has said at all and yet you keep claiming there is and nobody can reason with you. I just do not understand why you are suggesting there is something mysterious about water vapour having a terrible burning capacity when contacting colder human skin when it undergoes the phase change compared to a similar gas of similar heat capacity of the same temperature that does not undergo a phase change. Nearly all of your posts are alluding to something incredibly remarkable about the release of latent heat during the water phase change. Likewise this comment about sprayed apples not freezing. What you are doing is a bit weird and it is beyond me to make sense of what you doing.
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Post by nautonnier on Oct 21, 2016 11:11:52 GMT
Naut please stop, for your sanity. From what you have posted I think you have an engineering background and this stuff is central to your thinking but not to all on this site. Correct - and from the response, correct on both counts. Time to desist again.
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Post by Andrew on Oct 21, 2016 12:45:49 GMT
Naut please stop, for your sanity. From what you have posted I think you have an engineering background and this stuff is central to your thinking but not to all on this site. Correct - and from the response, correct on both counts. Time to desist again. Just too funny. Obviously Nonentropic does not realise he is siding with the phreakophysics side of the argument.
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Post by duwayne on Mar 13, 2017 22:24:14 GMT
I started this thread last year so I could better understand Nautonnier's and others' basis for claiming that CO2 isn't a greenhouse gas.
If you read through the thread, Nautonnier accepts that the CO2 radiation which strikes the land does cause some warming but he claims that the radiation which strikes the ocean results in no overall warming.
His case is based on the claim that the CO2 radiation which strikes the ocean passes from the ocean as latent heat in water vapor and upon condensation the latent heat is released as radiation which then passes into space without heating the atmosphere.
I agree with the first part that much of the energy from the CO2 radiation striking the ocean ends up as latent heat in water vapor, but when the water vapor condenses the latent heat is released as sensible heat (not radiation but heat you can sense or feel)into the atmosphere. It therefore significantly warms the atmosphere.
There is strong evidence for my claim that we all can see. Sensible heat from water vapor condensation is the fuel for thunderstorms and hurricanes. The heat release into the atmosphere causes an upward draft which lifts water vapor into a cooler environment which results in more condensation and more heat release and more upward drafts and so on as long as there is water vapor available.
This example shows why it is called latent heat rather than latent energy.
Everyone is free to come to their own conclusion, but so far I haven't seen any scientific source which supports Nautonnier's claim that latent heat is released directly as radiation energy.
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Post by nautonnier on Mar 14, 2017 1:11:18 GMT
I started this thread last year so I could better understand Nautonnier's and others' basis for claiming that CO2 isn't a greenhouse gas. If you read through the thread, Nautonnier accepts that the CO2 radiation which strikes the land does cause some warming but he claims that the radiation which strikes the ocean results in no overall warming. His case is based on the claim that the CO2 radiation which strikes the ocean passes from the ocean as latent heat in water vapor and upon condensation the latent heat is released as radiation which then passes into space without heating the atmosphere. I agree with the first part that much of the energy from the CO2 radiation striking the ocean ends up as latent heat in water vapor, but when the water vapor condenses the latent heat is released as sensible heat (not radiation but heat you can sense or feel)into the atmosphere. It therefore significantly warms the atmosphere. There is strong evidence for my claim that we all can see. Sensible heat from water vapor condensation is the fuel for thunderstorms and hurricanes. The heat release into the atmosphere causes an upward draft which lifts water vapor into a cooler environment which results in more condensation and more heat release and more upward drafts and so on as long as there is water vapor available. This example shows why it is called latent heat rather than latent energy. Everyone is free to come to their own conclusion, but so far I haven't seen any scientific source which supports Nautonnier's claim that latent heat is released directly as radiation energy. Well here is a satellite that records infrared output from weather systems. You can see the infrared matching the positions of the upwelling air at fronts. www.ssd.noaa.gov/goes/east/natl/flash-rb.htmlWhen a water molecule gives up the latent heat of evaporation (always the same amount regardless of ambient temperature) then that radiates away as photons. Sensible heat transfer would need to take place by collision at precisely the same time as the molecule enters a liquid or frozen state which is so unlikely it is improbable. You can see the radiation in the satellite imagery.
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Post by icefisher on Mar 14, 2017 9:39:12 GMT
I started this thread last year so I could better understand Nautonnier's and others' basis for claiming that CO2 isn't a greenhouse gas. If you read through the thread, Nautonnier accepts that the CO2 radiation which strikes the land does cause some warming but he claims that the radiation which strikes the ocean results in no overall warming. His case is based on the claim that the CO2 radiation which strikes the ocean passes from the ocean as latent heat in water vapor and upon condensation the latent heat is released as radiation which then passes into space without heating the atmosphere. I agree with the first part that much of the energy from the CO2 radiation striking the ocean ends up as latent heat in water vapor, but when the water vapor condenses the latent heat is released as sensible heat (not radiation but heat you can sense or feel)into the atmosphere. It therefore significantly warms the atmosphere. There is strong evidence for my claim that we all can see. Sensible heat from water vapor condensation is the fuel for thunderstorms and hurricanes. The heat release into the atmosphere causes an upward draft which lifts water vapor into a cooler environment which results in more condensation and more heat release and more upward drafts and so on as long as there is water vapor available. This example shows why it is called latent heat rather than latent energy. Everyone is free to come to their own conclusion, but so far I haven't seen any scientific source which supports Nautonnier's claim that latent heat is released directly as radiation energy. Well here is a satellite that records infrared output from weather systems. You can see the infrared matching the positions of the upwelling air at fronts. www.ssd.noaa.gov/goes/east/natl/flash-rb.htmlWhen a water molecule gives up the latent heat of evaporation (always the same amount regardless of ambient temperature) then that radiates away as photons. Sensible heat transfer would need to take place by collision at precisely the same time as the molecule enters a liquid or frozen state which is so unlikely it is improbable. You can see the radiation in the satellite imagery. i am a little confused. you stated the devastating effects of steam burns an obvious effect of latent heat being converted to sensible heat and conducting. why would that be an unlikely event in the atmosphere?
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Post by nautonnier on Mar 14, 2017 10:32:20 GMT
A steam burn occurs when the steam at ~100C hits a solid surface usually in a contained stream and many many molecules condense on that surface releasing infrared photons which are then absorbed by that surface. In the atmosphere things are very significantly more diffuse. To obtain sensible heat a molecule of N 2 or O 2 would need to be in contact with the H 2O at the moment of condensation. I am not even sure if latent heat that is held in the molecule as rotational and vibrational energy _ can_ be transferred and be mediated/conducted to kinetic energy of molecules of N 2 or O 2. If it is radiated out molecules of N 2 or O 2 will not be affected as they are not radiative gases however, other water molecules in the volume of air can absorb the radiated infrared. This is why they are so apparent on the satellite imagery because they are escaping I shall look for references on the transfer of energy released on state change. EDITJust adding this for some clarity of thought: Energy Energy is the ability or capacity to do work on some form of matter. There are several forms of energy, including the following: Potential energy is the energy which a body possesses as a consequence of its position in a gravitational field (e.g., water behind a dam). Kinetic energy is the energy which a body possesses as a consequence of its motion (e.g., wind blowing across a wind generator). It is dependent upon an object's mass and velocity (e.g., moving water versus moving air). Internal energy is the total energy (potential and kinetic) stored in molecules. Heat (or thermal) energy is kinetic energy due to motion of atoms and molecules. It is energy that is in the process of being transferred from one object to another because of their temperature difference. Radiant energy is the energy that propagates through space or through material media in the form of electromagnetic radiation. The First Law of Thermodynamics states that energy lost during one process must equal the energy gained during another. Methods of Heat Transfer Conduction- energy is transferred by the direct contact of molecules, not by the movement of the material Example: putting your hand on a stove burner. The amount of energy transferred depends on how conductive the material is. Metals are good conductors, so they are used to transfer energy from the stove to the food in pots and pans. Air is the best insulator, so good insulating products try to trap air and not allow it to move. Convection- energy is transferred by the mass motion of groups of molecules resulting in transport and mixing of properties Example: holding your hand over a stove burner. In meteorology, we speak of convection predominantly as that caused by rising currents of warm air. We refer to all other mass motions of air as advection. Radiation- energy is transferred by electromagnetic radiation Example: heat felt when standing away from a large fire on a calm night. Everything that has a temperature above absolute zero radiates energy. Radiation is not "felt" until it is absorbed by a substance. It does not require a medium to transfer energy through as do conduction and convection. okfirst.mesonet.org/train/meteorology/HeatTransfer.htmlAs Heat is conduction (as in sensible heat) I see no other way for the 'latent heat' of condensation to be released apart from infrared radiation.
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Post by duwayne on Mar 14, 2017 17:10:58 GMT
I started this thread last year so I could better understand Nautonnier's and others' basis for claiming that CO2 isn't a greenhouse gas. If you read through the thread, Nautonnier accepts that the CO2 radiation which strikes the land does cause some warming but he claims that the radiation which strikes the ocean results in no overall warming. His case is based on the claim that the CO2 radiation which strikes the ocean passes from the ocean as latent heat in water vapor and upon condensation the latent heat is released as radiation which then passes into space without heating the atmosphere. I agree with the first part that much of the energy from the CO2 radiation striking the ocean ends up as latent heat in water vapor, but when the water vapor condenses the latent heat is released as sensible heat (not radiation but heat you can sense or feel)into the atmosphere. It therefore significantly warms the atmosphere. There is strong evidence for my claim that we all can see. Sensible heat from water vapor condensation is the fuel for thunderstorms and hurricanes. The heat release into the atmosphere causes an upward draft which lifts water vapor into a cooler environment which results in more condensation and more heat release and more upward drafts and so on as long as there is water vapor available. This example shows why it is called latent heat rather than latent energy. Everyone is free to come to their own conclusion, but so far I haven't seen any scientific source which supports Nautonnier's claim that latent heat is released directly as radiation energy. Well here is a satellite that records infrared output from weather systems. You can see the infrared matching the positions of the upwelling air at fronts. www.ssd.noaa.gov/goes/east/natl/flash-rb.htmlWhen a water molecule gives up the latent heat of evaporation (always the same amount regardless of ambient temperature) then that radiates away as photons. Sensible heat transfer would need to take place by collision at precisely the same time as the molecule enters a liquid or frozen state which is so unlikely it is improbable. You can see the radiation in the satellite imagery. Nautonnier, the source of the IR in the graph you link to above was discussed earlier in this thread. It's not from latent heat release from the condensation of water vapor. On your second point, there are something like 200 billion stars in our galaxy. There are something like 200 billion galaxies in our universe. So there are maybe 40,000 billion billion stars in our universe give or take a few billion billion. It's about the same as the number of molecules of gas contained in a volume the size of a basketball at sea level. The molecules are constantly on "bouncing off" one another. So the number of molecular collisions is astronomical even when the air is thinner at higher elevations. It's not improbable that a water vapor molecule would collide and exchange sensible heat with another molecule every so often.
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Post by icefisher on Mar 14, 2017 17:52:19 GMT
A steam burn occurs when the steam at ~100C hits a solid surface usually in a contained stream and many many molecules condense on that surface releasing infrared photons which are then absorbed by that surface. In the atmosphere things are very significantly more diffuse. To obtain sensible heat a molecule of N 2 or O 2 would need to be in contact with the H 2O at the moment of condensation. I am not even sure if latent heat that is held in the molecule as rotational and vibrational energy _ can_ be transferred and be mediated/conducted to kinetic energy of molecules of N 2 or O 2. If it is radiated out molecules of N 2 or O 2 will not be affected as they are not radiative gases however, other water molecules in the volume of air can absorb the radiated infrared. This is why they are so apparent on the satellite imagery because they are escaping I shall look for references on the transfer of energy released on state change. EDITJust adding this for some clarity of thought: Energy Energy is the ability or capacity to do work on some form of matter. There are several forms of energy, including the following: Potential energy is the energy which a body possesses as a consequence of its position in a gravitational field (e.g., water behind a dam). Kinetic energy is the energy which a body possesses as a consequence of its motion (e.g., wind blowing across a wind generator). It is dependent upon an object's mass and velocity (e.g., moving water versus moving air). Internal energy is the total energy (potential and kinetic) stored in molecules. Heat (or thermal) energy is kinetic energy due to motion of atoms and molecules. It is energy that is in the process of being transferred from one object to another because of their temperature difference. Radiant energy is the energy that propagates through space or through material media in the form of electromagnetic radiation. The First Law of Thermodynamics states that energy lost during one process must equal the energy gained during another. Methods of Heat Transfer Conduction- energy is transferred by the direct contact of molecules, not by the movement of the material Example: putting your hand on a stove burner. The amount of energy transferred depends on how conductive the material is. Metals are good conductors, so they are used to transfer energy from the stove to the food in pots and pans. Air is the best insulator, so good insulating products try to trap air and not allow it to move. Convection- energy is transferred by the mass motion of groups of molecules resulting in transport and mixing of properties Example: holding your hand over a stove burner. In meteorology, we speak of convection predominantly as that caused by rising currents of warm air. We refer to all other mass motions of air as advection. Radiation- energy is transferred by electromagnetic radiation Example: heat felt when standing away from a large fire on a calm night. Everything that has a temperature above absolute zero radiates energy. Radiation is not "felt" until it is absorbed by a substance. It does not require a medium to transfer energy through as do conduction and convection. okfirst.mesonet.org/train/meteorology/HeatTransfer.htmlAs Heat is conduction (as in sensible heat) I see no other way for the 'latent heat' of condensation to be released apart from infrared radiation. Well there are a lot of papers on conduction rates in gases and it has a relationship to temperature and pressures of the gas. More highly pressurized gases have higher conduction rates. Conduction between two gases is no doubt far less understood but first of all diffusion rates are quite rapid and collisions are going to occur. Looking at conduction rates of gases against solid surfaces conduction with essentially only molecule motion (no convection, or wind forcing) heat conduction is roughly equal to the radiation rate of heat transfer. That suggests that the heat loss of the gas is being controlled by the diffusion rate of the otherwise still gas. Add in other induced motions like wind at 2 meters/sec the conduction rate accelerates to roughly 7 times that of the radiation rate (source European window glass heat transfer standards). Now looking at water vs steam the conductivity rate of water is about 30 times that of water vapor/steam and water is about 20 times more conductive than oxygen. So I would think some simple math would suggest that in a convecting and diffusing gas where the motion is a lot faster than 2 meters per second into another gas the collision/conductive transfer rate would not be negligible, I think one could theorize it a lot less than radiation but would be dependent upon convection speed and the fact you have a gas diffusing freely into another gas with instead of bouncing off a solid surface that their is a lot of collisions going on. It would only appear to be zero in a static sense but in the real dynamic world it would be a very large number of collisions.
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Post by icefisher on Mar 14, 2017 18:04:22 GMT
Well here is a satellite that records infrared output from weather systems. You can see the infrared matching the positions of the upwelling air at fronts. www.ssd.noaa.gov/goes/east/natl/flash-rb.htmlWhen a water molecule gives up the latent heat of evaporation (always the same amount regardless of ambient temperature) then that radiates away as photons. Sensible heat transfer would need to take place by collision at precisely the same time as the molecule enters a liquid or frozen state which is so unlikely it is improbable. You can see the radiation in the satellite imagery. Nautonnier, the source of the IR in the graph you link to above was discussed earlier in this thread. It's not from latent heat release from the condensation of water vapor. On your second point, there are something like 200 billion stars in our galaxy. There are something like 200 billion galaxies in our universe. So there are maybe 40,000 billion billion stars in our universe give or take a few billion billion. It's about the same as the number of molecules of gas contained in a volume the size of a basketball at sea level. The molecules are constantly on "bouncing off" one another. So the number of molecular collisions is astronomical even when the air is thinner at higher elevations. It's not improbable that a water vapor molecule would collide and exchange sensible heat with another molecule every so often. Here we go again. The IR seen in the graph includes IR from the release of latent heat. Thats because the release of latent heat sustains the temperature of the radiating gas so that it doesn't cool and radiate less. All the confusion occurs over this relatively simple concept. IR from cooler CO2 doesn't warm anything it just slows the cooling rate so it warms a "statistic" of the temperature called mean temperature. Then the same proponent of this idea, whose name shall not be uttered, then denies the exact same thing when somebody suggests that by sequestering heat from the latent heat for the purpose of raising mean temperature can not be used to keep anything warmer on average. Climate itself is effected both by actual warming and statistical warming but we have only been measuring it by statistical warming because the actual warming is not occurring. Actual warming occurs as the globe rotates and clouds disappear as the only way to actually warm something is via exposure to a warmer object.
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