Runaway warming on Venus?

[nick c]

Everybody misses the main point about the concept of a "runaway greenhouse effect" on Venus; they need to think in terms of a practical experiment.

- Build a greenhouse, with only Venus level light and see how hot it actually gets.

If anybody can get the temperature up to 800 degrees then they have solved the energy crisis because we can run steam off an 800 degree source. I'm not holding my breath.

In other words, people arguing for the "runaway greenhouse effect" have never actually built a greenhouse.

Exactly! This same point is made by Scott in The Electric Sky, p20:

But if sunlight entrapment in a mixture off gases can indeed cause the temperature to rise to 800 or 900 degrees F, then it should be possible to build an actual greenhouse here on Earth, fill it with a gaseous mixture identical to Venus' atmosphere, and sit back and watch the temperature rise. This would be a marvelously non-polluting energy source.
This experiment was never undertaken. But experiments did reveal that the actual cause of heat retention in a greenhouse is the glass roof and walls that prevent convection transfer of heat energy. If radiation is blocked, hot gases will rise. If there is no physical barrier to restrain them, they will rise until radiant losses to space cool them. Venus's atmosphere has no such glass ceiling. Neither does Earth's.

[Lucy Skywalker]

Nick, thanks for input here.

I get confused by the greenhouse arguments. This is why I am trying to stay off those and simply look at net "income and expenditure" of planetary energy for Venus.

I get confused by greenhouse arguments for Earth for these reasons:

Everyone in climate science, warmists and skeptics alike, say the earth would be 33 degrees cooler without the "greenhouse effect" of CO2. Climate skeptics say (this makes sense to me) that the reason that increases in current CO2 levels makes no difference is because once "opaqueness" has been reached regarding reflecting earth-origin radiation, one cannot really get any opaquer - or rather, the effect dies off logarithmically. All this says nothing about convection, but it's said anyway.

I take this much on trust since I have no means to hand of proving or disproving it and actually it doesn't matter. What matters is that we've seen no unusual warming and certainly nothing that can be "unequivocally" be attributed to CO2, that the correlation between temperature and CO2 is much weaker than temperature and sun (particularly if ocean is also factored in), that historically CO2 has lagged temperature not preceded it, and that even the CO2 rise can be explained in terms of the slow outgassing of the ocean (when the CO2-rich thermohaline current that sank in polar regions resurfaces in the tropics). There are other quirks that also disprove temperatures being driven by CO2. But that's more to get my sore head around. Try to stay with Occam's Razor and simplicity.

Of course the whole thing to me is "obviously" nonsense, even to think of CO2 having a serious warming effect at increasing concentrations. But in my situation I need facts people cannot duck. Not thought experiments that make sense to me.

I get confused by greenhouse arguments for Venus by some people talking about "adiabatic" warming because of the immense pressure of Venus atmosphere. Even though that supposedly supports hot Venus, it doesn't feel right to me because here too there has to be an overall balance of effects where adiabatic warming and cooling balance each other out in the total circulation of atmosphere. Again, I'd rather stay with net input and output as measured at the surface "just under" the albedo effect. I'd really rather have stayed with total solar irradiation and total output including reflection from albedo, as seen from outside. But Venus measurements as set out include albedo and therefore refer to the interior. It seems I have to just accept this. It seems that the upward and downward fluxes are being measured at a hypothetical non-point just under this "homogeneous reflecting surface".

Re. constructing a greenhouse with Venus conditions, this does speak to me as a reasonable experiment! Actually, total simulation of Venus atmosphere. There are two essential factors: the same high pressure, and the same quantity of CO2 per square cm. You'd have to make a horizontal pressurized tube, and bend the sunlight into it at one end. So - "Earthbound experiment utilizes a pressurized container filled with CO2 to simulate Venus". It seems obvious to me that the net cumulative heating effect would be very little, just as at the bottom of the oceans. What strikes me as most interesting about this experiment is that it hasn't been done!

Moreover, surely it should be incredibly easy to measure Venus' emitted flux from space - much easier than measuring from inside Venus' atmosphnere - and thus put to rest the arguments about output exceeding input. Again, the apparent non-existence of such measurements speaks to me since I'd expect them to be trumpeted.

[jjohnson]

Hi and a warm welcome, Lucy S,

If you haven't read Svensmark's The Chilling Stars, do so; it's a great forensic adventure into paleontology, geology, astronomy and physics to discover a plausible set of causes for Earth's climate. He's also at http://www.thecloudmystery.com

Charles Chandler, who posted here last year or so, has a new topic in the New Insights and Mad Ideas area, titled The Sun: Nuclear Fusion & Electric Reconnection. He's always fun to read and discuss things with, and he's into weather in a big way. Kudos to him - he knows how to think. That doesn't necessarily make him right (or wrong) - all that comes out in the wash eventually, but he can make things sound plausible enough that they merit some critical thought.

Glad to have another intelligently skeptical participant. This must be one of the most interesting, most fun forums on the web. You probably like reading in Cocktail Physics, too, speaking of fun! I know I have seen your posts somewhere else before - the "fits like Cinderella's slipper" remark rings a bell.

Cheers from the NW USA

Jim

[allynh]

Okay, I kept googling and found this awesome page.

The Real 'Inconvenient Truth'
http://www.junkscience.com/Greenhouse/

This article hits on all of the main points and offers some help on Venus as well.

Near the start of the page is this section talking about temperature of the Earth that should let you compute the temperature that Venus should be.

How much does the so-called 'greenhouse effect' warm the Earth?

It's estimated that the Earth's surface would be about -18 °C (0 °F, 255 K) with atmosphere and clouds but without the greenhouse effect and that the (we'll call it "natural") greenhouse effect raises the Earth's temperature by ~33 °C (59 °F).

We should note that devoid of atmosphere Earth would actually be a less-cold -1 °C (272 K) because the first calculation strangely includes 31% reflection of solar radiation by clouds (which obviously could not occur without an atmosphere) while ignoring that clouds add significantly to the greenhouse effect. Granted it's kind of a bizarre to include clouds in one half the calculation and not the other but that is the way it's commonly done, so, for simplicity, just stick with ~33 °C.

The workings: thermal equilibrium for an Earth without an atmosphere:

The sun behaves approximately like a black body of radius rs=6.599 x 105 Km, at a temperature of Ts=5,783 K. The radiative flux at the sun's surface is given by the expression σTs4, where σ is the Stefan-Boltzmann Constant (5.6704 x 10-8 Wm2K4). Flux refers to radiation per unit area. Thus, at the Earth's distance from the sun, res=1.496 x 108 Km, this flux is reduced by the factor (rs/res)2. The Earth's disk has a cross section, acs=πre2, where re is the Earth's radius (6.378 x 103 Km), and thus intercepts acsσTs4(rs/res)2 radiation from the sun. In order to balance this intercepted radiation, the Earth would warm to a temperature Te, where σTe44πre2 = acsσTs4(rs/res)2. This leads to a solution Te=272 K.

Clouds, which obviously require an atmosphere, and other features of the Earth reflect 31% of the incident radiation. Taking this into account reduces Te to 255 K.

Theoretically, if the planet's surface cooled by radiation alone, then the greenhouse-induced surface temperature would be much warmer, about 350 K (77 °C). Atmospheric motion (convective towers carrying latent and sensible heat upwards and large scale circulation carrying it both upwards and polewards) circumvent much of the greenhouse effect and significantly increase the "escape" of energy to space, leaving Earth's surface more than 60 °C cooler than a static atmosphere would do.

Additionally, greenhouse gases are only able to absorb radiation in very specific electromagnetic frequencies and Earth does not radiate limitless amounts of energy in the appropriate bandwidths. This means there is 'competition' for available energy and significant greenhouse potential is unrealized (carbon dioxide could absorb more than 3 times the energy it currently does in the atmosphere were it not for competition from clouds and water vapor, clouds alone could absorb 50% of available energy but manage to capture just 14% and so on...).

So, despite there being far more greenhouse gas in the atmosphere than required to achieve the current greenhouse effect, something which has been true since before humans discovered fire, evapo-transpiration and thermals transport heat higher in the atmosphere where radiation to space is increased. This is why Earth remains about 15 °C (288 K) rather than about 77 °C (350 K).

This is the main equation:

σTe44πre2 = acsσTs4(rs/res)2

This equation simplifies down to:

Te = 1/4 root of ( 0.25 (Ts4(rs/res)2))

Go to the webpage to see the formula clearly and then plug in the numbers for Earth and Venus from Wiki:

Earth
http://en.wikipedia.org/wiki/Earth

Earth Numbers
Semi-major axis 149,598,261 km
~ res = 1.496 x 108 Km

Albedo - 0.367 (geometric)
0.306 (Bond)<---------I think that they are using this number.

Venus
http://en.wikipedia.org/wiki/Venus

Venus numbers
Semi-major axis 108,208,930 km
~ rvs = 1.082 x 108 Km

Albedo - 0.67 (geometric)
0.90 (Bond)<---------Venus has an albedo of 0.90! That means that most of the light hitting Venus is reflected away! Looking at the Wiki page, a value of 0.90 is the same albedo as "Fresh snow".

Albedo
http://en.wikipedia.org/wiki/Albedo

So whatever the Tv for Venus is it will be that much cooler.

Earth (To check the example given above.)

Te = 1/4 root of ( 0.25 (5,783 K)4(6.599 x 105 Km / 1.496 x 108 Km)2)) = 272 K

I don't see how the albedo of 0.306 fits into the equation to get their value of Te = 255 K, but at least my number without atmosphere matches theirs.

Now here's Venus

Tv = 1/4 root of ( 0.25 (5,783 K)4(6.599 x 105 Km / 1.082 x 108 Km)2)) = 318 K

Notice that the distance of Venus from the Sun is not much less than the Earth. As I mentioned up thread, Pre Space Age Venus was well within the "life zone", and with the albedo making the planet as reflective as "fresh snow" the actual temperature of Venus should have been only a bit more than Earth.

Like I've mentioned, I've lost my ability to do simple Math, so please check my numbers. If you see how to work the albedo into the equation, let me know. Thanks...

[davesmith_au]

I'd like to echo the warm welcome Lucy, I'm sure you'll have much to offer and some to learn, and that's why we're all here (well, most of us anyhow...).

I've split the AGW arguments out from this thread to keep it on the original topic.

AGW or not? (split from - Runaway warming on Venus?)

Whilst we don't interfere much with topic wandering on this forum, it seemed like the original topic was getting swamped by the AGW debate. The latest post by you Lucy, went over there as some of it was addressing PersianPaladin's post, and I cannot split an individual post into two. Sorry about that, you may want to re-post half of it here.

Anyhow, carry on, I've enjoyed reading the relevant posts in this thread.

Cheers, Dave.

[Lucy Skywalker]

First, thanks Dave for splitting the thread. Nuisance getting derailed like that.

Second, And thanks to everyone, my question in the title of the thread has been answered for my needs for the mo. Dusty Devil gave me the vital clues in the New Scientist reference and the other. But it would be good to have access to more trustworthy info - I've found a paper on Venus that is done by a Velikovsky supporter, whose figures re input and output I can now understand - and I wonder what people here think about it? http://www.firmament-chaos.com/papers/fvenuspaper.pdf I've not noticed either here or on Ackerman's website, much sign of interaction with the EU folk here, who seem to represent the real global discussion forum. Does anyone know this paper?

I realize that although I love the EU concept re. current state of the Universe, I'm just not sure about the reliability of "origins" hypotheses either here or in Ackerman's paper - as yet. I'm also ignorant - but my copy of Thunderbolts of the Gods has just arrived so I can see what is actually being said and suggested.

An amazing world is opening up for me right now. I'm rather busy reading, in addition to keeping up in Climate Science material. Transmutation of elements (Kervran, and some very interesting-but-watch-your-step-like-a-hawk material just surfacing on LENR) Physics background to the Philadelphia Experiment (part of understanding the power of electro-magnetics). UFO material (suspect it's behind reverse-engineering for our laptops). Plus the basics here. I think this is all science we need for the future, and it needs to be as it were, Open Source and freed from destructive /dogmatic attitudes. Amazing what's happening, but none too soon either.

DON'T COMMENT ON EITHER OF THE LAST TWO PARAGRAPHS!! START A NEW THREAD IF YOU MUST. STAY WITH VENUS HERE and Ackerman's paper she's still cuddly

[Lloyd]

VENUS HEAT LOSS

Allyn said: Venus has an albedo of 0.90! That means that most of the light hitting Venus is reflected away! Looking at the Wiki page, a value of 0.90 is the same albedo as "Fresh snow".

* Yeah, facts like that are what had scientists expecting Venus to be very cold, before satellites landed on it.
* Here's something about Venus losing heat.
http://www.mikamar.biz/symposium/thrnhill.txt
Slide 27. Finally, a word about the high surface temperature of Venus. It is the remnant internal heat from Venus' birth producing the hellish surface conditions. It is not due to an atmospheric greenhouse effect, which has been equated to expecting a well insulated oven to be able to melt lead with only the pilot light switched on. I think Charles Ginenthal effectively wiped out the greenhouse theory yesterday. What's more, and it wasn't mentioned yesterday, the atmosphere " breathes" every 4 days indicating a build-up of heat beneath the clouds followed by some form of energy release and relaxation back to the beginning of the cycle. The energy required to raise the planet's atmosphere through several kilometers every 4 days is considerable. The four day rise and fall was also confirmed when the Magellan orbiter was dropped low enough to start atmospheric braking.
* This thread, Solar plasma Induces Breathing of Earth’s Atmosphere, at http://www.thunderbolts.info/forum/phpB ... =15#p25179 discussed related matters.

[nick c]

Lloyd quoted Wal Thornhill: "I think Charles Ginenthal effectively wiped out the [Venus] greenhouse theory yesterday."

The presentation to which Wal is referring is available in 5 parts on You Tube, here:

http://www.youtube.com/watch?v=nCDS7JmUhl8

http://www.youtube.com/watch?v=SeO17fBKdEQ

http://www.youtube.com/watch?v=rsA-Q6t8DuA

http://www.youtube.com/watch?v=5uFJK4wbWMg

http://www.youtube.com/watch?v=jSChap64n40


The text:
http://www.mikamar.biz/symposium/ginenthl.txt


Nick

[allynh]

I stumbled across:

Encyclopædia Britannica Eleventh Edition
http://en.wikipedia.org/wiki/Encycloped ... th_Edition

I was hoping to find something like this online. The old texts show what little we knew, and seem a bit more honest in their ignorance. There are links to multiple sources of the scanned pages.

One of the Wiki guys has the whole thing up at:

http://en.wikisource.org/wiki/User:Tim_ ... t_PNG_demo

The two pages for the Venus entry are at:

page 1013

http://en.wikisource.org/w/index.php?ti ... ge=ED7B040

page 1014

http://en.wikisource.org/w/index.php?ti ... ge=ED7B041

The word Galaxy isn't even listed, nor Universe, everything was still Nebula. The entry for Nebula starts at page 332:

http://en.wikisource.org/w/index.php?ti ... ge=EC9A348

Just keep clicking "next" to move through the pages.

Look at Nebular Theory, page 333, as the first, hesitant, description of how the Solar System was formed.

http://en.wikisource.org/w/index.php?ti ... ge=EC9A351

This is how the entry begins and ends.

They clearly state that it is all speculation, with no proof.

The past 100 years of Science has merely frozen what was once hopeful speculation into what is now carved-in-stone dogma; still with no proof. Ha!

This is exactly the type of book/set I hoped to find. The B&W versions from the Internet Archive are best for what I need.

This is gold!

[Lucy Skywalker]

Aaaaaagh -= just realized, from reading above posts more carefully, that the figure I've been using for albedo as per Dust Devil's references (80%) is NOT the albedo stated above, and as at Wikipedia currently (90%). That upsets my certainties again. Too tired to deal with this tonight.

[Lucy Skywalker]

Nick, thanks a lot for the U-tubes Ginenthal presentation plus text.

Ginenthal, from Part 4 @ 6 mins thru Part 5, does the level of proof I need very well, in conjunction with the New Scientist 1980 quote. It seems that at present I cannot trust Ted Holden or even John Ackerman so long as both quote the 80% albedo figure without either them or myself explaining the discrepancy with the 90% albedo figure allynh and wikipedia now quote. But with Ginenthal, the albedo doesn't matter, he's gone to the heart of the matter.

Scientists repeatedly "adjusting" their figures until the figures give what their "Runaway Venus Greenhouse" theory tells them they should have.

This is exactly what ex-NASA astrophysicist James Hansen has done to our global GISS temperatures. Ex-post-adjustments, shamelessly serially scandalous.

But now I know with help from friends

[Lloyd]

[I thought I posted this here, but it ended up at the other thread.]

Lucy said: Second, I've found a paper on Venus that is done by a Velikovsky supporter, whose figures re input and output I can now understand - and I wonder what people here think about it? http://www.firmament-chaos.com/papers/fvenuspaper.pdf I've not noticed either here or on Ackerman's website, much sign of interaction with the EU folk here, who seem to represent the real global discussion forum. Does anyone know this paper? Already I realize that although I love the EU concept re. current state of the Universe, I'm just not sure about the reliability of "origins" hypotheses either here or in Ackerman's paper - as yet. I'm also ignorant - am waiting for my copy of Thunderbolts of the Gods so I can see what is actually being said and suggested.

* This thread tries to explain how EU theory developed: http://thunderbolts.info/forum/phpBB3/v ... =10&t=4156.
* This one is mostly Cardona's explanation of his Saturn Theory [my favorite]: http://thunderbolts.info/forum/phpBB3/v ... =10&t=3824.
* I hadn't heard of Ackerman until you mentioned him recently. So I checked out his site. I see that he adheres to Velikovsky's dating of the near-collisions with Venus and Mars, which most of the myth researchers have not done. So his dating needs to be corrected. Also, he accepts a modified Nebular Hypothesis, which EU theorists reject, in favor of electrical formation of planets, moons, stars, quasars and galaxies. However, he seems to have excellent info on the present conditions on Venus etc. I really like his explanation of the contents of Venus' lower atmosphere in contrast to its upper atmosphere. He says the lower is mostly sulphur compounds, while the upper is mostly CO2. I also like his suggestion that the sulphur, which is outgassing from the molten interior, is cooling down and that outgassing will stop when the surface cools down some more in a few centuries or so, meaning humans will be able to land there. He explains that the CO2 part of the atmosphere is not what makes the lower atmosphere so dense, but only the sulphur does so. So, when the sulphur stops erupting, the lower atmosphere will no longer be so dense. I think humans should take a small icy asteroid to Venus and dump it there to cool Venus off, so we can colonize it almost pronto.

[davesmith_au]

[I thought I posted this here, but it ended up at the other thread.]

Sorry Lloyd, it wasn't intentional, splitting threads is never an easy task, and I often seem to jigger it up for someone... At least you have the sense to realize the error and correct it without raising a fuss, thanks.

Cheers, Dave.

[Jarvamundo]

Nick, thanks a lot for the U-tubes Ginenthal presentation plus text.

+1 mate, thanks