Latent Heat: An Alternative Explanation

In summary, the conversation discusses the concept of "latent heat" and its role in the heat budget of the global free atmosphere. It is believed that during the condensation process, energy is released by water vapor molecules and absorbed by the remaining humid air, causing a temperature increase. However, the lack of direct observation of this energy release has led to speculation that it may not exist. The conversation also includes an analogy to explain the selective removal of the least energetic molecules during condensation, resulting in a paradoxical increase in temperature. The conversation ends with a reminder to follow forum rules and the closure of the thread.
  • #1
klimatos
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1. In studies of the heat budget of the global free atmosphere, the concept of “latent heat” (now known as “enthalpy of condensation”) plays an important role[1].

2. Both observation and experiment confirm that when humid air condenses the temperature of the remaining air increases[2].

3. This temperature increase is believed to be caused by the release of energy by the water vapor molecules during the condensation process and its contemporaneous absorption by the remaining humid air[3].

4. Yet, to the best of my admittedly limited knowledge, no such release has ever been actually observed!

5. I suggest that the reason for this lack of observation is because no such energy as described in (3) exists. The very real temperature increase described in (2) is a simple statistical anomaly.

6. When condensation occurs, I maintain that the condensation process is selective. That is, the least energetic molecules are the most likely to be attracted to the hygroscopic condensation nuclei or to the hygroscopic proto-droplet. These least energetic molecules are, by the definition of temperature, the coolest molecules.

7. By selectively removing the coolest molecules, the mean temperature of the remaining molecules increases.

8. Let me offer an analogy. Imagine a large room containing a considerable number of people. Each individual has a certain amount of money on their person. The total amount of money in the room is analogous to the enthalpy content of a mass of humid air. The average amount per person is analogous to the temperature of our mass of humid air. We request that every individual with less than a certain amount of money step out of the room and into the lobby (analogous to condensation). After they leave, the total amount of money in the room is diminished, but the average has gone up.

9. So it is with condensation. You remove heat and the temperature goes up. A rather nice paradox. [1] Kiehl, J. T. and Trenberth, K. E., 1997: “Earth’s Annual Global Mean Energy Budget”, Bulletin of the American Meteorology Society, Vol. 78, No. 2, February 1997.
[2] R. R. Rogers and M. K. Yau, A Short Course in Cloud Physics, Butterworth & Heinemann, 1988.
[3] Ibid.
 
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  • #2
Is this new? How is this different than the Maxwell Demon?

Zz.
 
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  • #3
klimatos said:
2. Both observation and experiment confirm that when humid air condenses the temperature of the remaining air increases[2].
...
4. Yet, to the best of my admittedly limited knowledge, no such release has ever been actually observed!
Your 2 contradicts your 4. The experiments mentioned in 2 are the observation of energy release. Every person who has been treated for burns from steam can also attest to having observed this quite viscerally. Second degree steam burns are simply not explainable by statistically “cold” molecules preferentially sticking to skin with no energy transfer. Also temperature and energy of phase changes are directly measured with common devices like differential scanning calorimeters. Far from being unobserved, this is routinely observed with relatively inexpensive precision equipment.

The entire rest of your post is based on a completely false premise.

Additionally, I remind you of the forum rules and recommend that you check them before further posting.
 
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  • #4
Dale said:
Additionally, I remind you of the forum rules and recommend that you check them before further posting.
I have reread the forum rules and concede that I am in violation of them in posting a speculation. My apologies to all.
 
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  • #5
Thank you for checking @klimatos

I will go ahead and close this thread.
 

Related to Latent Heat: An Alternative Explanation

1. What is latent heat?

Latent heat is a type of energy that is absorbed or released during a phase change of a substance, such as from solid to liquid or liquid to gas. It is the energy required to change the state of a substance without changing its temperature.

2. How is latent heat different from specific heat?

Specific heat is the amount of energy required to raise the temperature of a substance by one degree, while latent heat is the energy required to change the state of a substance without changing its temperature. Specific heat is a property of a substance, while latent heat is a property of a phase change.

3. What are some examples of latent heat?

Some examples of latent heat include the energy absorbed when ice melts into water, or the energy released when water vapor condenses into liquid water. It is also involved in processes such as evaporation, sublimation, and deposition.

4. How is latent heat important in our daily lives?

Latent heat plays a crucial role in many everyday processes, such as cooking, refrigeration, and weather patterns. It is also a key factor in the Earth's climate, as the energy absorbed or released during phase changes affects the distribution of heat in the atmosphere and ocean.

5. Can latent heat be harnessed as a source of energy?

Yes, latent heat can be harnessed as a source of energy through processes such as steam power generation and geothermal energy. However, the amount of energy that can be obtained from latent heat is limited and highly dependent on the specific substance and phase change involved.

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