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Comment on Thermodynamics, Kinetics and Microphysics of Clouds by Pekka Pirilä

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AK,
The Quantum Mechanical basis for the difference between bosons and fermions is that switching two identical bosons leaves the wave function unchanged while switching two identical fermions changes the sigh of the wave function.

When other properties of the state make such switching likely enough this property of the bosons adds to the likelihood of the combined state formed by having two bosons in the same state, because (1+1)^2 = 4 while 1^2+1^2 = 2. Having two fermions in the same state is forbidden, because (1-1)^2 = 0.

To have this enhancement for the bosons the two particles must be so closely in the same state that the effect adds up over the whole range, where the particles may move. Even slightly different momenta lead to incoherence, where the effect disappears.

In supeconductivity the situation is different, because the effective masses are very low. For that reason the coherence may be present even at relatively high temperatures. (The theory of superconducivity is rather complex. I haven’t gone trough it in full detail in spite of the fact that I have lectured from a book that spends much space for superconductivity, but that was many decades ago.)


Comment on Thermodynamics, Kinetics and Microphysics of Clouds by AK

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The chemical composition of ‘a particle’ changes when dissolved in water…

And again when it dries out. Not necessarily the same particle (depending on its composition), but potentially still a CCN.

And, of course, many particles aren’t completely soluble…

Comment on Thermodynamics, Kinetics and Microphysics of Clouds by niclewis

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Judith
Hearty congratulations to you and Professor Khvorostyanov! The book seems a very impressive achievement; I hope it gets the attention and recognition it deserves. Well done for writing it. The subject is absolutely central, inter alia, to the questions of how much effect aerosols have had and on how the climate will respond to increasing greenhouse gas concentrations.

Comment on Thermodynamics, Kinetics and Microphysics of Clouds by WebHubTelescope

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But no one abuses Bose-Einstein statistics in this way for ordinary matter. Sure they use it with photon statistics to derive the Rayleigh-Jeans law and then the Stefan-Boltzmann distribution, but for physical matter like this?
LOL!

They assume Maxwell-Boltzmann for thermal activation (fine) and then when they want to generate a different solution, they suddenly change it to Bose-Einstein because it gives them the answer they want?
LOL !

And they are doing all this strangeness without and kind of citation to back it up. LOL !

That is the problem with these textbooks. No one has enough time to review them for logical consistency. A paper, yes, but not something of this magnitude, likely not.

Comment on Thermodynamics, Kinetics and Microphysics of Clouds by mwgrant

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Kim wrote “the odd cow won’t follow the herd.”

We need even parity cows. scows?

Comment on Thermodynamics, Kinetics and Microphysics of Clouds by Wagathon

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Isn’t the presence of CCN the opposite of drying out?

Comment on Thermodynamics, Kinetics and Microphysics of Clouds by Wagathon

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The San Diego City Council badly wanted water: the people needed Cjarles M. Hatfield. Their recently finished reservoir had lain bone dry for three years; and, they agreed to pay Hatfield $10,000 to fill it up — no rain, no pay, no risk: what could go wrong? Hatfield took the job. If successful the fee would’ve been like receiving $230,000 today. With his little brother’s help he built a 20-foot tower where he mixed and burned a secret mixture of chemicals, shot off bombs into the skies and lo, Hatfield caused it to rain. The people wanted rain and it did.

For weeks it poured rain. It was the worst rain ever — worst flood in the county’s history. That was in 1916. Rivers rose, water topped and broke through dams, communities became islands, roads, bridges, rails and farm animals were washed away, houses floated down the river and out to sea, settlements disappeared and many people died in the “Hatfield Flood.”

Murder charges against Hatfield were considered. Lynching was threatened. Rather than receiving a fee — that he walked 60 miles over broken roads to collect — the ex-sewing machine salesman turned moisture enhancer, Hatfield was forced to flee. Years later he sued for his fee in court and lost. Apparently, all of that rain was due to natural causes and not the action of a man.

Comment on Thermodynamics, Kinetics and Microphysics of Clouds by ceresco kid

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I am actually feeling sorry for Web. Clearly out of his league.


Comment on Thermodynamics, Kinetics and Microphysics of Clouds by WebHubTelescope

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Pekka said:


The chapter 8.2.3 is not problematic anyway as it only mentions that Bose-Einstein statistics applies, in principle, while the rest of the book
is evidently based on Bolttzmann statistics.

In principle ???

Flip the page and they ASSERT that nucleation rates are proportional to kT when the Bose-Einstein statistics are applied — and this is in the high temperature limit compared to the activation energy!!

But the problem is that this then grows without bound; yet we know that real-world activation curves go like exp(-E/kT), which becomes proportionally less effective the higher the temperature.

I have never seen someone abuse Bose-Einstein statistics in this way, and then have nothing to back it up by way of citations.

Comment on Thermodynamics, Kinetics and Microphysics of Clouds by David L. Hagen

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Wagathon: Has anything changed besides the players and the scale? cf <a href="http://qz.com/138141/china-creates-55-billion-tons-of-artificial-rain-a-year-and-it-plans-to-quintuple-that/" / rel="nofollow">China creates 55 billion tons of artificial rain a year—and it plans to quintuple that</a> <blockquote>Last year, the head of the China Meteorological Administration (CMA) revealed that under its new “weather modification program” it would use cloud-seeding to boost precipitation by 254 billion tonnes (280 billion tons) . . . “[The Chinese government has] made some claims but there is no evaluation available that can substantiate their claims,” Roelof Bruintjes, a scientist at the US National Center for Atmospheric Research and a proponent of weather modification, </blockquote> <a href="http://english.caixin.com/2012-08-13/100423557.html?p0&_ga=1.262139213.1304456232.1408990461#page1" rel="nofollow">Stormy Weather on Cloud-seeding</a> <blockquote> in May, the head of the China Meteorological Administration (CMA) provided details on the new weather modification program, adding that the country would seek to increase precipitation by 3 to 5 percent in the next five years through cloud-seeding.</blockquote> OR <a href="http://www.tandfonline.com/doi/pdf/10.1080/17441730.2014.902159" rel="nofollow">Is this part of the essential effort to keep social stability?</a> <blockquote> China was then, and remains, the major contributor to this global problem, accounting for approximately 40 million of the more than 100 million missing women at the turn of the twenty-first century (Klasen & Wink, 2003) . . . For every ‘missing’ woman there is a ‘surplus’, ‘excess’ or ‘unmatched’ man, and future projections suggest that <b>by 2030 there could be close to thirty million Chinese men seeking a Chinese wife but unable to find one.</b></blockquote>

Comment on Thermodynamics, Kinetics and Microphysics of Clouds by WebHubTelescope

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ceresco kid | September 4, 2014 at 6:26 pm |

I am actually feeling sorry for Web. Clearly out of his league.

Yeah, too bad that I am competing against the minor leagues. It’s almost beneath my dignity.

But what can I say — the Harlem Globetrotters had to play the hapless Washington Generals.

Comment on Thermodynamics, Kinetics and Microphysics of Clouds by Pekka Pirilä

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WHUT,
I don’t have the book, I have seen only that part of the chapter that you included in your message.

That part of your argument seems to be correct that B-E statistics cannot be applied in the way the book appears to be doing. The energy differential must be calculated from a real effective minimum, not between two states at temperature far from the absolute zero. The possible states at a higher temperature are not nearly coherent enough to be significantly affected by the boson nature of water molecules.

As a side remark, for one issue the bosonic nature of H2O might have observable influence. That’s the case of dimers at high altitude, where collisions are not too frequent.

Comment on Thermodynamics, Kinetics and Microphysics of Clouds by David L. Hagen

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vukcevic re thanks for the perspective. PS Note: <a href="http://en.wikipedia.org/wiki/Monsoon_of_South_Asia" rel="nofollow">South Asia Monsoon</a> The SUMMER monsoon carries moisture from the Indian Ocean (especially the Bay of Bengal) to rain out over the Himalayas. The WINTER monsoon coming over Tibet carries little water.

Comment on Thermodynamics, Kinetics and Microphysics of Clouds by Tom Fuller

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Mind if I wait for the movie?

Comment on Trenberth’s science communication interview by Alexander Biggs

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WebHubTelescope (@WHUT: So another attack on Australians, why not say something constructive, like exactly why their theories won’t work.


Comment on Thermodynamics, Kinetics and Microphysics of Clouds by AK

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Sorry, I assumed you understood this stuff, and I was just reminding you.

A particle capable of becoming wet functions as a CCN. Thus, it’s in (roughly at the center of) a (cloud) droplet. Several things can happen to this droplet:

It can become caught up in a larger hailstone/droplet, ultimately falling as rain. Most of this rain will reach the surface, some will re-evaporate, producing a (usually) much larger particle made up of all the non-volatiles contained in all the original CCN’s.

It can get caught up in entrainment of some sort, mixing with dry air. Depending on circumstances, the resulting mixture may join a downdraft, or otherwise undergo (wet/pseudo-)adiabatic heating, wherein the water will evaporate and the particle dry out.

It can become involved in snow creation, where the vapor pressure over the (supercooled) water of the droplet is higher than that over ice, and most of the water evaporates and condenses as ice/snow. Depending on how hygroscopic the particle is, it may dry out, or remain wet with a bit of the droplet left, due to reduction in vapor pressure due to dissolved matter.

There may be other things that can happen to the droplet, that I haven’t remembered to include.

In two of the cases above, the particle can potentially be “recycled”, functioning more than once as a CCN. In addition, the mini-droplets surrounding hygroscopic CCN’s can also dry out once the source air mixes with dryer stratospheric air. The key question is: how often do all of these things happen; how much is the original aerosol load “multiplied” by such recycling?

Comment on Thermodynamics, Kinetics and Microphysics of Clouds by Rob Ellison

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I have found that cows are particularly fond of a trumpet solo. It seems to ring their bell.

Comment on Thermodynamics, Kinetics and Microphysics of Clouds by beththeserf

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So much cloudiness in climate. I must buy the book, fer even
a serf may learn – if assisted by a scientist nephew.

Comment on Thermodynamics, Kinetics and Microphysics of Clouds by Carrick

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AJ: <blockquote>For instance, the two electrons that work together to create a covalent bond are Fermions, but the union of those two electrons can, for some purposes, be considered a Boson. But not all purposes, or every atom would look like a helium or lithium atom.</blockquote> Well yes. There are many different physical properties that determine the behavior of a molecule besides whether it is a boson or fermion. H2O is obviously a much larger molecule than He2, it's melting point is much higher, etc. I'm not sold that Bose-Einstein statistics is a very useful description of the dynamics of water molecules, but it's not obviously wrong. On semi-classical physicals: One example where modeling the non-classical behavior of water vapor molecules is importan is the <a href="http://journals.ametsoc.org/doi/pdf/10.1175/1520-0469%281995%29052%3C1924%3AANLAHI%3E2.0.CO%3B2" rel="nofollow">ice nucleation on supercooled water droplets.</a> This was exampled at -40°C, so this apparently would have relevance to cloud formation physics. For supercooled water, it also appears that <a href="http://www.nature.com/srep/2013/130617/srep01980/full/srep01980.html" rel="nofollow">the bosonic nature of the molecule can matter.</a>

Comment on Thermodynamics, Kinetics and Microphysics of Clouds by WebHubTelescope

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I will classify the chapter 8.2.3 in this book as <a href="http://en.wikipedia.org/wiki/Not_even_wrong" rel="nofollow">"Not even wrong"</a> The problem with science that is "not even wrong" is that many times one can not even gauge what the fundamental premise of the proposer's argument is. I took a guess at what they are trying to do, but unless one can get in to their shoes and figure out exactly where or why they went south, we may never know. As it stands and IMO, they decided to pick Bose-Einstein statistics on a whim and then derived something without any experimental evidence or citation of previous work.
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