Friday, July 29, 2016

Jupiter's Giant Red Spot is red hot & explained by the gravito-thermal greenhouse effect

A new paper published in Nature finds Jupiter's Great Red Spot is red hot at about 2,420°F or 1,330°C (i.e. almost hot enough to melt steel at 1425°C) and that this observation, 
"could solve the mystery of the unusually high temperatures observed throughout Jupiter's upper atmosphere, which can't be explained by solar heating alone. [nor by a radiative greenhouse effect]"
"Previous heat-distribution models suggested that Jupiter's atmosphere should be much cooler, largely because the planet is about fives times further from the sun than Earth is. So, having ruled out solar heating from above, the authors of the new research found evidence suggesting this atmospheric heating is largely driven by a combination of gravity waves and acoustic waves generated by turbulences in the atmosphere below the Great Red Spot.
"Giant planets like Jupiter are measured to be hundreds of degrees warmer than current temperature models predict. Before now, the extremely warm temperatures observed in Jupiter's atmosphere have been difficult to explain, due to the lack of a known heat source."
In other words, the very hot atmospheric temperatures on Jupiter cannot be due to an Arrhenius radiative greenhouse effect. The atmosphere of Jupiter is mostly comprised of the non-greenhouse gases hydrogen and helium, but does contain small amounts of the IR-active 'greenhouse' gas water vapor. However, the Maxwell/Clausius/Carnot gravito-thermal greenhouse effect perfectly explains the observed atmospheric temperature profile of Jupiter, making Jupiter the ninth planet in our solar system to follow the simple Poisson relationship of atmospheric mass/gravity/pressure to temperature. The Poisson relationship was demonstrated in another recent paper:

Referring to fig. 1 of the paper, we find at 0.1 bar pressure on Jupiter, the corresponding temperature is~112°K, and at 11 bars pressure corresponds to 400°K or 260°F:

Fig 1 from the paper. The dotted line is the atmospheric temperature vs. pressure curve on Jupiter. At 11 bars pressure, the temperature is 400°K or 127°C or 260°F.  
This satisfies the Poisson Relation (which in turn is derived from the Ideal Gas Law) previously demonstrated on 6 8 other celestial bodies in our solar system:


T/To = (P/Po)^0.286 ~= 400°K/112°K = (11 bar/0.1 bar)^.286

where
T = temperature at 11 bars pressure =  400°K
To= temperature at top of atmosphere = 112°K
P = 11 bars
Po= pressure at top of atmosphere = 0.1 bar

and once again demonstrates that the catastrophic anthropogenic global warming (CAGW) theory is a myth, that atmospheric temperatures are controlled by mass/gravity/pressure and are independent of greenhouse gas concentrations on any of these 9 planets with atmospheres, including Earth. Adding additional CO2 plant food to the atmosphere will undoubtedly green the Earth, but Earth's climate sensitivity to CO2 is effectively zero. 

Related: How can Uranus have storms hot enough to melt steel? A runaway greenhouse effect?


Jupiter's Great Red Spot is Also Red Hot, Study Shows

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Jupiter's Great Red Spot is apparently also red hot: The highest temperatures ever observed on the planet were recently detected in the region above the ginormous storm.  
The Great Red Spot (GRS) is a massive storm about twice the diameter of Earth that lies in lowest layer of Jupiter's atmosphere. About 497 miles (800 kilometers) above this humongous storm, astronomers measured temperatures reaching about 700 degrees Fahrenheit (about 370 degrees Celsius) higher than normal, James O'Donoghue, lead author of the new study and a research scientist with Boston University's (BU) Center for Space Physics, told Space.com. 
The new finding could solve the mystery of the unusually high temperatures observed throughout Jupiter's upper atmosphere, which can't be explained by solar heating alone.[Jupiter's Great Red Spot: Photos of the Solar System's Biggest Storm
Generally, atmospheric temperatures on Jupiter are around 1,700 degrees F (around 930 degrees C), with the exception of areas above the planet's poles, which are heated by auroras. Above the Great Red Spot, however, the atmosphere is about 2,420 degrees F (about 1,330 degrees C), O'Donoghue said. 



Observations show that Jupiter's upper atmosphere — above the Great Red Spot — is hundreds of degrees hotter than anywhere else on the planet.
Observations show that Jupiter's upper atmosphere — above the Great Red Spot — is hundreds of degrees hotter than anywhere else on the planet.

Previous heat-distribution models suggested that Jupiter's atmosphere should be much cooler, largely because the planet is about fives times further from the sun than Earth is. So, having ruled out solar heating from above, the authors of the new research found evidence suggesting this atmospheric heating is largely driven by a combination of gravity waves and acoustic waves generated by turbulences in the atmosphere below the Great Red Spot. The new study was published today (July 27) in the journal Nature. 
Atmospheric gravity waves — not to be mistaken for gravitational waves — occur when pockets of air collide with things like mountains. The resulting effect is similar to when a pebble is dropped into a lake, and ripples then form on the surface of the water.  
Acoustic waves, on the other hand, are sound waves, which means they develop from compressions and refractions in the air and travel upward into the atmosphere. There, they encounter regions of lower density and break, much like ocean waves breaking on the shore. When this happens, the acoustic waves release stored kinetic energy and cause molecules and atoms in the air to move around more, which then raises the temperature, O'Donoghue said.  
"Changes in density around the Great Red Spot will shoot waves in all directions," O'Donoghue added. "We believe that acoustic waves are the majority of the heating cause, because gravity waves tend to ship their energy across the planet, rather than vertically up like acoustic waves." 



This illustration shows how a combination of gravity and acoustic waves transfers heat above the Great Red Spot to Jupiter's upper atmosphere.
This illustration shows how a combination of gravity and acoustic waves transfers heat above the Great Red Spot to Jupiter's upper atmosphere.
Credit: Art by Karen Teramura, UH IfA, James O'Donoghue

The GRS is a massive storm that rotates counterclockwise, colliding with the natural flow of molecules in the atmosphere, which are moving opposite the storm. These types of collisions create turbulence that creates acoustic and gravity waves, O'Donoghue said. 
Using data from the SpeX instrument on the NASA Infrared Telescope Facility (IRTF) on Mauna Kea mountain in Hawaii, the researchers were able to measure the temperature of Jupiter's atmosphere, specifically around the GRS.  
"The Great Red Spot is the largest storm in the solar system — it is bigger than Earth itself — so it generates a lot of turbulence that impedes the flow of air in the atmosphere," O'Donoghue said. "It is kind of like when you stir a cup of coffee and you turn the spoon around and go the opposite way. Suddenly, there is a lot of sloshing [turbulence] going on that generates sound waves, or compressions of air, upwards for you to hear."  
The heat generated from the acoustic and gravity waves has a localized effect, which suggests there is a coupling between low and high altitudes, as energy is transferred from the lower atmosphere to the upper atmosphere. Previously, the connection between low and high altitudes was thought to be pretty much impossible because the distance is so vast, O'Donoghue explained.
"This new result from Jupiter provides the first evidence of upward coupling of energy that finds its way from the lower atmosphere to the upper atmosphere," Michael Mendillo, a professor of astronomy at BU, who was not involved with the study, told Space.com. "It's a very interesting observation — even on Earth, this mechanism is not well-studied or understood. If this happens on Jupiter, it is possible that it happens on all planets." 
Giant planets like Jupiter are measured to be hundreds of degrees warmer than current temperature models predict. Before now, the extremely warm temperatures observed in Jupiter's atmosphere have been difficult to explain, due to the lack of a known heat source, Tom Stallard, co-author of the new study and an associate professor of astronomy at the University of Leicester in the United Kingdom, told Space.com. 
"Sometimes, ironically, it is easier to see these features on a planet far away [from Earth]," said Stallar, who advised O'Donoghue throughout his research. In other words, "It's much more difficult to step back and see these broadscale effects … on Earth, so it's interesting to use Jupiter as a 'proxy' for what might be happening on other planets, and that includes Earth."
With the Juno spacecraft orbiting Jupiter, the researchers hope to get an up-close view of the Great Red Spot and isolate where the heat observed in the planet's upper atmosphere comes from. They also plan to study the fine details of smaller storms like Red Spot Jr., to see if there is heating above them as well. 

13 comments:

  1. The gravito-thermal concept involving convective overturning which requires a permanent surface reservoir of kinetic energy to fuel it is the only plausible explanation for the heat that is observed over and above that supplied by the sun.
    Gravity waves and acoustic waves are only relevant in relation to the distribution of the atmosphere's convectively available potential energy ( CAPE in meteorology) some of which is apparently focused in the red spot but in kinetic form as a by product of the particular circulation pattern within Jupiter's atmosphere.

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    1. Thank you Stephen. Agreed.

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    2. Jupiter generates heat from gravitational contraction, as addressed by Lord Kelvin,

      https://en.wikipedia.org/wiki/Kelvin%E2%80%93Helmholtz_mechanism

      and radiates more energy than it receives from the sun. The greenhouse effect will result in a temperature lapse rate the higher in the atmosphere you go. With no greenhouse effect, you get no temperature lapse rate.

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  2. "With no greenhouse effect, you get no temperature lapse rate." is false.

    The lapse rate = -g/Cp and neither gravity (g) nor heat capacity (Cp) are dependent upon radiation or an Arrhenius radiative greenhouse effect. With just a gravito-thermal GHE and no greenhouse gases, convection would ensue and there would be a lapse rate.

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    1. No, the temperature would be the same throughout the atmosphere.
      The PRESSURE would drop off exponentially, but not the temperature.
      See

      https://wattsupwiththat.com/2012/01/24/refutation-of-stable-thermal-equilibrium-lapse-rates/

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    2. The convection would soon stop because the warm air higher in the atmosphere not lose heat without the greenhouse effect.

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    3. No, gravity will still create a Boltzmann distribution with a temperature gradient. This is explained by Feynman's lecture 40 on statistical mechanics of a pure N2 column:

      http://hockeyschtick.blogspot.com/2015/07/physicist-richard-feynman-proved.html

      http://hockeyschtick.blogspot.com/2014/11/why-greenhouse-gases-dont-affect.html

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  3. ren says:
    August 1, 2016 at 6:18 AM
    Tropopause rises and falls depending on the pressure gradient equilibrated by gravity.
    http://www.cpc.ncep.noaa.gov/products/stratosphere/strat-trop/gif_files/time_pres_TEMP_MEAN_ALL_NH_2015.png
    http://www.cpc.ncep.noaa.gov/products/stratosphere/strat-trop/gif_files/time_pres_TEMP_MEAN_ALL_EQ_2016.png

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    1. As the warm air rises, it will expand and cool. Since the air that rose previously through convection wouldn't lose heat and cool off, the warm air at the surface would NOT rise, expand and cool, since it would be no lighter than the air it was trying to replace.

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    2. The air at the surface is warmer due to higher pressure. This rises, expands and cools and then repeats the cycle by falling, compressing and warming. No radiation or greenhouse gases are required for these processes, as explained by Feynman in the link above for a pure N2 atmosphere.

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  4. I am not physicist, but I am good in logic. And I think many times over it may be more important to ask the right questions, rather than working through detailed answers to the wrong questions.

    My question is: what if we had gods hands and could simply do away with the clouds on Venus?
    All of a sudden, without weakening the atmosphere itself, or taking away CO2, the sun could shine directly onto the surface. And of course, the intense heat on the surface could deradiate right into space. Also the albedo of Venus would decrease significantly. What would happen?
    a) With the lower albedo now, and "green house gases" remaining constant, would temperatures go up even more?
    b) Would temperatures stay the same, as a gravito-thermal GHE suggests?
    c) or would temperatures actually fall off sharply, as my common sense suggests?

    When it comes to surface temperatures, we are very much discussing temperatures, but hardly the term "surface". As pointed out, it makes little sense considering the firm core of a gas giant "surface". Then why are we doing so with a "gas dwarf" like Venus?

    Climatic surface, from my point of view, should be the place where radiation exchange is actually taking place. If Venus for instance has an albedo of 0,75, it will absorb 25% of solar radiation. But only 2% of which make it to the firm surface. Which means 23% of the total will actually heat the atmosphere, most of it the upper cloud layers at roughly 50km altitude. The temperatures there are around 330°K. A perfect black body (pbb) in Venus' orbit should have 328°K. I do not think this is incidence.

    Overall there is one obvious confusion in the term surface. While clouds on earth are counted the surface with regard to albedo, they not part of the surface when it comes to determining average surface temperatures.

    Then .. clear sky albedo of earth is =< 0.1. A fact that tends to be denied, or exagerated respectively. But this animation reveals the truth:

    https://de.wikipedia.org/wiki/Mond#/media/File:Dscovrepicmoontransitfull.gif

    (take a snapshot, minimize colors, and you can directly compare the brightsness of moon and earth)

    Emissivity of earth again is around 0.9, which evens out with (1 - 0.1), so clear sky earth should indeed have the temperature of a pbb, of about 280°K. In other words 3/4 of the "green house effect" are due to the interpretation of the role that clouds play. And simple observation suggests, they have rather a neutral than a cooling effect. That is in strong opposition to IPCC claims, that clouds would decrease surface temperatures by 17-18°K by the albedo effect, while only contributing 3.5-4°K to the "green house effect".

    And I would argue, that the remaining quarter is also due to clouds. Like on Venus, they can virtually move the therodynamic "surface" upwards, giving way to elevated temperatures on the firm surface due to adiabatic effects.

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    Replies
    1. The pressure vs temperature curves of the overlapping portions on Earth & Venus are almost identical, proving temperatures are controlled by the gravito thermal greenhouse effect & alleged "heat trapping" by CO2 is a myth.

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  5. I do not oppose the concept of a gravito thermal GHE, and I also do agree that CO2 and green house gases are a myth. But I would strongly doubt that clouds would have a cooling effect.

    It is a trivial observation: when the night is overcast, nocturnal cooling is strongly reduced, easily to a third of what it would be otherwise. Clouds might be blocking sun light even more efficiently (than terrestial infrared), but a rate of 2/3 is hard to overcome, and even if, only by a slim margin.
    That alone strongly contradicts the overwhelming cooling effect clouds are supposed to have.

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