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Groups > sci.physics > #594033
| From | Thomas 'PointedEars' Lahn <PointedEars@web.de> |
|---|---|
| Newsgroups | sci.physics |
| Subject | Re: Convection is fiction |
| Date | 2016-08-21 17:57 +0200 |
| Organization | PointedEars Software (PES) |
| Message-ID | <23764527.rf7BzDKH0Z@PointedEars.de> (permalink) |
| References | <e5b8b178-c782-4768-ac07-0cf0b4f62c15@googlegroups.com> <upq9rb9itah8fb03u990e1ppt12tsbr004@4ax.com> |
Michael J. Strickland wrote: > Thunderheads go to 50-60 thousand feet and they must have some > moisture. Nonsense. 50'000 to 60'000 ft equal 15.24 to 18.29 km. The troposhere only extends up to ca. 12 km altitude from sea level. The adjacent higher atmospheric layer of Terra is the stratosphere (from ca. 12 km to ca. 50 km) where there are occasionally clouds, but none that (could) contribute to precipitation (directly). > I don't think hail can form only 1000 meters up in hot summer air. Correct. But hailstones form when upwinds push water droplets (ca. 200 µm in diameter, too small to see individually, therefore clouds) further up the cloud, where, due to the low temperatures, they freeze to ice pellets (between 200 µm and 5 mm). Being too heavy to be held in suspension by upwinds, they fall down again, where more water can condense on them, and they are pushed up again, where that water freezes on. And so on until the pellets are too heavy even in the lower parts of the cloud (or the upwinds slow down due to insufficient convection), when they finally fall out of the cloud. While hailstones do form in cumulonimbus clouds that extend up to 12 km altitude, you are neglecting the basic physical fact that the air does not stay “hot” at higher altitudes: as it rises, it cools. In 3 km altitude and above, so in the *lower* part of a cumulonimbus already, the air temperature is already below 0 °C – low enough for water to freeze – even in summer. <https://upload.wikimedia.org/wikipedia/commons/9/9d/Comparison_US_standard_atmosphere_1962.svg> > Water vapor rises because water (H2O at 18 grams/mole) is less dense > than air which is predominately nitrogen (N2 at 28 grams/mole). When > mixed with regular air (non-moist), this brings the air's > average/overall density down and causes it to rise above non-moist > air. Nonsense. Air contains about 1 % of water which is gaseous (water vapour) under standard conditions. It is not the water vapour in the air alone that rises, but warm air with water vapour in it. When it cools, only the water in the air condenses (on condensation nuclei, small dust particles in the air, ca. 0.2 µm in size) and freezes; more water condenses and freezes on that, to form ice crystals and eventually ice pellets. It does that because the boiling and melting point of water is significantly higher (100 °C and 0 °C under standard conditions, respectively) than that of the other constituents of air – given the same atmospheric pressure that is decreasing approximately exponentially with altitude within the higher troposphere: p ≈ p₀ exp(−g M h∕(R T₀)) where p – atmospheric pressure p₀ – standard atmospheric pressure at sea level (101'326 Pa) g – Earth-surface gravitational acceleration (ca. 9.81 m∕s²) M – molar mass of dry air (ca. 0.03 kg∕mol) h – altitude R – universal gas constant (ca. 8.31 J mol⁻¹ K⁻¹) T₀ – standard temperature at sea level (288.15 K = 15 °C) -- PointedEars Twitter: @PointedEars2 Please do not cc me. / Bitte keine Kopien per E-Mail.
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Convection is fiction Claudius Denk <claudiusdenk@gmail.com> - 2016-08-13 09:44 -0700
Re: Convection is fiction James McGinn <jimmcginn9@gmail.com> - 2016-08-13 15:14 -0700
Re: Convection is fiction Michael J. Strickland <michael06582@comcast.net> - 2016-08-17 19:01 -0400
Re: Convection is fiction James McGinn <jimmcginn9@gmail.com> - 2016-08-17 16:28 -0700
Re: Convection is fiction James McGinn <jimmcginn9@gmail.com> - 2016-08-17 22:20 -0700
Re: Convection is fiction Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-08-21 17:57 +0200
Re: Convection is fiction Poutnik <poutnik4nntp@gmail.com> - 2016-08-21 18:16 +0200
Re: Convection is fiction Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-08-21 18:46 +0200
Re: Convection is fiction Poutnik <poutnik4nntp@gmail.com> - 2016-08-21 18:56 +0200
Re: Convection is fiction Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-08-21 19:09 +0200
Re: Convection is fiction Poutnik <poutnik4nntp@gmail.com> - 2016-08-21 19:27 +0200
Re: Convection is fiction Poutnik <poutnik4nntp@gmail.com> - 2016-08-22 07:39 +0200
Re: Convection is fiction James McGinn <jimmcginn9@gmail.com> - 2016-08-22 19:58 -0700
Re: Convection is fiction Poutnik <poutnik4nntp@gmail.com> - 2016-08-22 17:17 +0200
Re: Convection is fiction James McGinn <jimmcginn9@gmail.com> - 2016-08-22 20:02 -0700
Re: Convection is fiction James McGinn <jimmcginn9@gmail.com> - 2016-08-21 12:38 -0700
Re: Convection is fiction Claudius Denk <claudiusdenk@gmail.com> - 2016-08-21 17:11 -0700
Re: Convection is fiction James McGinn <jimmcginn9@gmail.com> - 2016-08-21 19:59 -0700
Re: Re: Convection is fiction Michael J. Strickland <michael06582@comcast.net> - 2016-08-21 22:34 -0400
Re: Convection is fiction Poutnik <poutnik4nntp@gmail.com> - 2016-08-22 06:52 +0200
Re: Re: Convection is fiction Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-08-22 19:02 +0200
Re: Convection is fiction Poutnik <poutnik4nntp@gmail.com> - 2016-08-22 19:17 +0200
Re: Convection is fiction James McGinn <jimmcginn9@gmail.com> - 2016-08-22 20:05 -0700
Re: Convection is fiction Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-08-24 01:16 +0200
Re: Convection is fiction Poutnik <poutnik4nntp@gmail.com> - 2016-08-24 05:53 +0200
Re: Convection is fiction Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-08-24 18:47 +0200
Re: Convection is fiction Poutnik <poutnik4nntp@gmail.com> - 2016-08-24 21:04 +0200
Re: Convection is fiction Poutnik <poutnik4nntp@gmail.com> - 2016-08-24 06:09 +0200
Re: Convection is fiction Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-08-24 19:03 +0200
Re: Convection is fiction Sergio <invalid@invalid.com> - 2016-08-24 12:16 -0500
Re: Convection is fiction James McGinn <jimmcginn9@gmail.com> - 2016-08-24 11:11 -0700
Re: Convection is fiction Poutnik <poutnik4nntp@gmail.com> - 2016-08-24 21:36 +0200
Re: Convection is fiction Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-08-25 06:20 +0200
Re: Convection is fiction Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-08-25 08:13 +0200
Re: Convection is fiction Sergio <invalid@invalid.com> - 2016-08-25 09:40 -0500
Re: Convection is fiction James McGinn <jimmcginn9@gmail.com> - 2016-08-21 12:14 -0700
Re: Convection is fiction Poutnik <poutnik4nntp@gmail.com> - 2016-08-22 17:45 +0200
Re: Convection is fiction Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-08-22 18:56 +0200
Re: Convection is fiction Poutnik <poutnik4nntp@gmail.com> - 2016-08-22 19:14 +0200
Re: Convection is fiction Poutnik <poutnik4nntp@gmail.com> - 2016-08-22 20:54 +0200
Re: Convection is fiction Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-08-24 01:56 +0200
Re: Convection is fiction Poutnik <poutnik4nntp@gmail.com> - 2016-08-24 06:02 +0200
Re: Convection is fiction Poutnik <poutnik4nntp@gmail.com> - 2016-08-24 06:14 +0200
Re: Convection is fiction Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-08-24 19:07 +0200
Re: Convection is fiction Poutnik <poutnik4nntp@gmail.com> - 2016-08-24 21:15 +0200
Re: Convection is fiction Poutnik <poutnik4nntp@gmail.com> - 2016-08-24 06:31 +0200
Re: Convection is fiction Poutnik <poutnik4nntp@gmail.com> - 2016-08-24 06:54 +0200
Re: Convection is fiction Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-08-24 01:10 +0200
Re: Convection is fiction Poutnik <poutnik4nntp@gmail.com> - 2016-08-24 05:53 +0200
Re: Convection is fiction Poutnik <poutnik4nntp@gmail.com> - 2016-08-24 07:32 +0200
Re: Convection is fiction Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-08-24 19:15 +0200
Re: Convection is fiction Poutnik <poutnik4nntp@gmail.com> - 2016-08-24 21:11 +0200
Re: Convection is fiction Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-08-24 21:26 +0200
Re: Convection is fiction Sergio <invalid@invalid.com> - 2016-08-24 15:07 -0500
Re: Convection is fiction James McGinn <jimmcginn9@gmail.com> - 2016-08-22 20:04 -0700
Re: Convection is fiction Claudius Denk <claudiusdenk@gmail.com> - 2016-08-21 19:31 -0700
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