Why we live on Earth and not Venus

earth-venus-compareFrom the University of British Columbia:

Compared to its celestial neighbors Venus and Mars, Earth is a pretty habitable place. So how did we get so lucky? A new study sheds light on the improbable evolutionary path that enabled Earth to sustain life.

The research, published this week in Nature Geoscience, suggests that Earth’s first crust, which was rich in radioactive heat-producing elements such as uranium and potassium, was torn from the planet and lost to space when asteroids bombarded the planet early in its history. This phenomenon, known as impact erosion, helps explain a landmark discovery made over a decade ago about the Earth’s composition.

Researchers with the University of British Columbia and University of California, Santa Barbara say that the early loss of these two elements ultimately determined the evolution of Earth’s plate tectonics, magnetic field and climate.

“The events that define the early formation and bulk composition of Earth govern, in part, the subsequent tectonic, magnetic and climatic histories of our planet, all of which have to work together to create the Earth in which we live,” said Mark Jellinek, a professor in the Department of Earth, Ocean & Atmospheric Sciences at UBC. “It’s these events that potentially differentiate Earth from other planets.”

On Earth, shifting tectonic plates cause regular overturning of Earth’s surface, which steadily cools the underlying mantle, maintains the planet’s strong magnetic field and stimulates volcanic activity. Erupting volcanoes release greenhouse gases from deep inside the planet and regular eruptions help to maintain the habitable climate that distinguishes Earth from all other rocky planets.

Venus is the most similar planet to Earth in terms of size, mass, density, gravity and composition. While Earth has had a stable and habitable climate over geological time, Venus is in a climate catastrophe with a thick carbon dioxide atmosphere and surface temperatures reaching about 470 C. In this study, Jellinek and Matt Jackson, an associate professor at the University of California, explain why the two planets could have evolved so differently.

“Earth could have easily ended up like present day Venus,” said Jellinek. “A key difference that can tip the balance, however, may be differing extents of impact erosion.”

With less impact erosion, Venus would cool episodically with catastrophic swings in the intensity of volcanic activity driving dramatic and billion-year-long swings in climate.

“We played out this impact erosion story forward in time and we were able to show that the effect of the conditions governing the initial composition of a planet can have profound consequences for its evolution. It’s a very special set of circumstances that make Earth.”

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What – no warning that we are on our way to become Venus II if we don’t park our cars right now? What incompetent communication office botched this press release?

george e. smith

Well the primary reason we live on “Earth” and not “Venus”, is because that’s what they named the place.
What idiot would call their home planet MW_OA 2/3_M 4392_3 as if it was just some entry in a star catalogue.
And in any case if we did happen to live on that planet I mentioned above, we would be a life form that could evolve compatibly with the conditions on that planet.
We are here, because if the conditions were considerably different like they are most other places; something else would be here instead of us.
g

Auto

+ rather a lot.
Auto

James Bull

As Spike Milligan’s character in the Goons says “every ones got to be somewhere”.
James Bull

PaulH

The Earth is roughly 93,000,000 miles from the sun, and Venus is roughly 67,200,000 miles. When the Earth drifts 25,000,000 miles closer to the sun, I’ll start to worry.
Does CO2 cause orbital decay?
/snark

SMC

Of course CO2 causes orbital decay. CO2 is the magic molecule. I am disturbed by you lack of faith.

Me too.
Terribly disturbed.
Somebody call Lew and Cook.
Let’s get this fixed, asap.

joelobryan

The biggest question is why Jupiter didn’t wander inward and eject the inner rocky planets out of the solar system, gobble them up, crush them like the asteroid belt, or put them into freezing cold highly elliptical orbits.
The answer to that likely has to do with Saturn Uranus Neptune gravitationally restraining the much larger Jovian planet.
I subcribe to the Rare Earth postulate, whereby all of a large assortment of unlikely events came together 4.5-4.0 Gya that made Earth a relatively stable platform for the evolution of highly complex biological machines. Whether their is any real intelligence here on Earth remains open to debate.

Kelvin Vaughan

Yeah we can’t even get our spelling correct.

george e. smith

So what scientific evidence do you have that this large assortment of events isn’t the norm, so that similar life supportable planets are all over the place.
We currently have one single observation; we are here. You can’t do any sort of statistical analysis on a single observation, so you have no basis for claiming this is a rare circumstance.
By the way; just in case you misread me, I don’t think there is anything at all special about this place; but I also do believe it is the only such inhabited place in the entire universe; not that it matters a jot, if it isn’t. And no I also don’t believe that it didn’t just happen all by itself.
g

MarkW

george, the observational evidence is all the other planetary systems found to date.
They all have Jupiter or larger planets very close to their sun.

Expat

Consistent spelling is indicative of a lack of imagination.

Mikedep

Pretty sure Jupiter (and the other gas giants) developed closer to the Sun, then have slowly drifted out to their current positions.

Colin M

“And no I also don’t believe that it didn’t just happen all by itself.” – crystal clear, got it, thanks George.
And as for it not mattering a jot if Earth is or isn’t he only inhabited place in the entire universe? Seriously? In terms of science and humanity as a whole,what could possibly matter more than that? Other than reducing CO2 emissions of course…
I’m more and more in favour of the Rare Earth theory combined with the Great Filter (being behind us, thank goodness); it is incredibly unlikely for a planet to end up with conditions we have that allow it to be suitable for life, and it is incredibly unlikely for life to begin, and incredibly unlikely for life to make the jump from prokaryote to eukaryote, and the odds of all three things happening in the same place, well, that’s a once in a universe event. Even if there is multicellular life out there, somewhere, the odds of it being intelligent – tool making, communicating, space-faring intelligent, are virtually nil, and the odds of it being close enough to us for us to actually encounter them in any way are absolutely nil. We are alone.

Menicholas

I think life is inevitable, as it drifts among the planets and stars. But that is a purely speculative thought, based on the odds, and the age of the Earth relative to the age of the Universe, and considering the likelihood or spores some such surviving a trip on a space faring rock, as opposed to the odds of life arising spontaneously on a planetary surface in a relatively short span that it would have needed to have done.
It may be that more stable conditions exist in nebulae or some other non-gravitationally bound environment.
The existence of extremophiles here on Earth in everyplace we have looked, including inside of solid rock miles beneath the surface, along with the numerous observations that simple meteor impacts can and regularly do blast rocks from one planet into space which eventually land on other planets and moons, and the knowledge that other sorts of catastrophic events in long ago and far away star systems gave rise to the nucleogenesis which created the atoms in our bodies which subsequently disbursed, the re-agglomerated to be here when needed, makes me think that rocks with life spores of some sort could be free floating or imbedded in dust grains, or riding on larger rocks or in ice and making similar journeys. It need not be likely or quick to have plenty of chances and time to occur in a large galaxy over 14 billion years.
The large planetismal which impacted the Earth and led to the formation of the moon was highly influential on how the Earth turned out. It may well be the case that without this impact and all the unique changes it has brought about, both in chemical composition of the crust and atmosphere, and other more subtle ways, we would not be here.
As for the late heavy bombardment being responsible for changes on Earth which somehow did not affect our neighboring worlds, how is that logical? The bolides all hit one planet with a heavy bombardment, but missed the other ones nearby?
I doubt that is how it went down, although in the case of Mars, it was likely just random chance it survived, as the body which created the moon is thought to have been roughly Mars sized. If so, this would imply that multiple Mars sized bodies existed late in the formation process of the Solar System. Since this idea of the origin of the moon implies that they were in orbits with insufficient stability to prevent crossings of two such planet sized bodies, it may be the case that other bodies of similar size were ejected from the Solar System altogether.
Of course, any ideas I or anyone else has about speculative matters such as the origins of life, the universe, the solar system or, for that matter, complex multicellular life, or even consciousness itself, stands a high chance of being completely wrong.
Any ideas which wind up being a correct description, which were dreamed up using thin evidence, are correct only by random chance, IMO.
How many of the ideas that people had a few thousand years ago have stood the test of time? Sure, the Greeks speculated that there were atoms, but how many other ideas of the structure of matter came and went and held sway since then?
How likely was it that anyone could have guessed that fire was what it was, or than there were things all around us that we could not see but nonetheless held the power of life or death over us all?
The more things change, the more they stay the same, and people have always thought they had everything pretty much all figured out.

AnonyMoose

Of course most discovered planets around other stars are huge and close to their star. Those are the planets which are easiest to detect.

george e. smith

Well Mark W, I don’t believe I said there weren’t any other planets. Every star could have nine of them just like Sol does.
Yep we just discovered the other day that Sol has a ninth planet called Pluto. It’s not a rock; now that we’ve had a look at it.
g
PS The “Drake equation” that proves there’s an infinity of intelligent life containing planets out there; simply forgot to include the improbability of the likely (and necessary) sequence of chemical syntheses, (that so far we have NOT been able to duplicate), that had to happen in the correct order, in the correct environmental circumstances, to get to ANY life form on Earth, let alone any intelligent form. And to date, there has been no evidence, that ” intelligence ” conveys any greater likelihood of survival, than just being big and mean and ugly like the dinosaurs.
And no, that does not lead to any conclusion of ” intelligent design ” which to me is even more improbable, than it all just happening by itself.

Sturgis Hooper

IMO microbes are probably common in the universe, multicellular life less so and complex macroscopic organisms even less, requiring relatively stable environments for long ages. The central region of galaxies is however unlikely to be hospitable to living things.
Life may well have developed independently on earth or could have arrived here via meteorites, which in any case are loaded with organic chemical precursors of life, as indeed is the universe at large.
Advances in understanding the origin of life have recently been made, although science may never know for sure how it occurred with high certainty at every step. The overall picture is now pretty clear, however. Further development from the earliest archaea and bacteria is however better understood, ie, the evolution of eukaryotes and multicellular organisms.

BBReggie

I agree Paul. Proximity to the sun is the reason Venus is much hotter than Earth and why life evolved here.

Isn’t Venus hotter than Mercury, even though Mercury is closer to the sun than Venus?

Eustace Cranch

Amazing how they studiously ignore that very very obvious difference.

Arsten

Venus’ atmosphere is 92 bars of pressure (Earth Sea level = ~1 bar) at the surface and the overall composition is 96% CO2 and 3% Nitrogen. Mercury has an exospheric atmosphere at 10^-15 bars, which is 42% oxygen, 29% sodium, and 22% hydrogen.
It misleading to ask the question “Isn’t Venus hotter than Mercury, even though Mercury is closer to the sun than Venus?” because you are comparing a all-but barren rock to an atmospheric rocky world.
It’s also misleading to say that any one factor (CO2 or solar radiation) is the reason that Venus is so hot because pressure and density of the atmosphere are why Venus is so hot compared to other atmospheric rocky worlds. If our atmosphere was stripped of all CO2 and then densified to the extent that Venus’ is it would exhibit similar thermal properties. The precise temperature would also be far more dependent upon the incoming solar radiation in this state than our current temperature differences – Venus would still be hotter (it needs the spot light. What can I say?)

SMC

Let’s See, Mercury effectively has no atmosphere to insulate it. Could be something there to explain why Venus is hotter than Mercury.

Holding spectrum as seen from the sun constant , the temperature of a planet is inversely proportional to the square root of its distance from the sun :
http://cosy.com/Science/AGWpptSBplanetTemps.jpg
This is basic physics which should be part of every highschool physics curriculum .
We are about 3% warmer than a gray ( flat spectrum ) body in our orbit . Venus’s surface temperature is about 225% the gray body temperature in its orbit .
There is no material spectrum which will produce a solar heat gain within an order of magnitude of that given Venus’s ~ 0.9 albedo wrt to the solar spectrum .
It’s surface temperature must be due to internal heat held in by that very radiantly insulative atmosphere .
James Hansen’s howler that Venus is an example of a “runaway greenhouse” would have caused him to be ridiculed into obscurity rather make him a climate scare millionaire if “climate science” were the functioning branch of applied physics which it ought to be .

JJM Gommers

Bob Armstrong is correct, temperature on Venus is determined by internal heat and vulcanic activity.

What? The inverse square law is still a thing? I thought they abolished that a while ago.

Along with the rest of the science I learned at school.

Menicholas

An increase of a few one hundredths of one percent of a trace gas will boil the oceans, broil us all alive in our potato skins, and end human civilization within a few tens to hundreds of years, based on some almost surely trivial alteration of a few watts per square meter in energy balance. But being 1/3 closer to the sun and the inverse square relationship of energy input to the planet…
Krikey!
If one looks at the ionization constants, and the effect of the solar wind in the absence of a magnetic field, and somewhat lower gravity, and other such factors…one may see that lighter elements are far more likely to be scrubbed clean out of the atmosphere on Venus. Goodbye hydrogen, so goodbye water, and the moderating influence of it.
But really, that thirty million miles makes a huge difference, as perhaps does not having an oversized moon.
How many reasons do we need?

beng135

Bob Armstrong says:

It’s surface temperature must be due to internal heat held in by that very radiantly insulative atmosphere .

Bob, I don’t think that’s right — if it were, the IR emission from Venus would be greater than the absorbed input. I think the observed IR emission of Venus equals the calculated net solar input (solar exposure minus albedo reflection).

I think the observed IR emission of Venus equals the calculated net solar input

Can you provide any references ? Those are essential observations .
Given Venus’s half-year long night , and the assertion that it’s pre-dawn surface temperature is nearly the same as its evening temperature , I continue to be skeptical of any cause other than geothermal heating .
Unfortunately , as with many of us , to paraphrase SpiderMan , with no funding , comes no time .

highflight56433

Funny! …maybe as the mass of the sun decays over time, the solar wind and orbital velocity of the earth will gradually cause the earth to migrate further from the sun. In that scenario, earth would need a thicker atmosphere to slow heat loss. … and a sign that says “ice not welcome here” 🙂
I don’t see the point of the research other than it’s a pay day.

dccowboy

Sadly, as the mass of the sun decays over time, it will also expand in size. I think (although I have no empirical evidence to back it up, thus it remains speculation) that the suns expansion will more than overcome any orbital drift of the earth, eventually leaving us closer to the sun’s surface than we are today. Not a scenario that a thicker atmosphere will help I’m afraid. But, baring successful immortality research, none of us (nor the next million generations or so) have to worry about it. 🙂

Alan the Brit

I presume they knew every component to put into their puter model (preuming how they “played out” their story) with nothing assumed, presumed, or guest?

Ray Boorman

Alan, you presume too much. My guess is that 80% of the variables in their model were pure guesses.

There’s a 90% chance you’re correct.

Resourceguy

There is one other key difference between Earth and Venus. On Venus there is pure science to conduct and on Earth there are political science wars and purges against fact checkers.

Gentle Tramp

Yes, and one can see these science wars e.g. by no longer mentioning some very basic facts like in this quote from above:
“On Earth, shifting tectonic plates cause regular overturning of Earth’s surface, which steadily cools the underlying mantle, maintains the planet’s strong magnetic field and stimulates volcanic activity. Erupting volcanoes release greenhouse gases from deep inside the planet and regular eruptions help to maintain the habitable climate that distinguishes Earth from all other rocky planets.”
Well, and what very basic fact is missing here? Volcanoes on Earth don’t only maintain the habitable climate by releasing “greenhause gases” (primarily CO2) but maintain – first and foremost – Life itself!
Without volcanic degassing our atmosphere would lose all of its CO2 because of limestone sedimentation and other similar biological/geological processes after some 1.5 Million years. And with no CO2 in the atmosphere there would be no more photosynthesis and consequently no more Life on Earth! Never forget:
CO2 is the GAS OF LIFE !!!

Bill Illis

You are not going to have water on and in the crust of Venus-sized planet at Venus distance from the Sun, when the rotation rate has the length of day being 116 Earth days long. The Sun is up for 2700 hours straight. Joules accumulate at the surface for 2000 hours straight. At the rate Earth’s surface accumulates joules during the day, Venus’ surface gets to 400C in the daytime. All water is baked out in the very first day.
No water in the crust, no plate tectonics, thick atmosphere, crust melts out every few 100 million years with no plate tectonics, elements capable of being released as a gas are then released, even thicker atmosphere. Energy is shared across the darkside with such a thick atmosphere. Hot Venus.

phodges

I agree with Bill. No water, no plate tectonics.
Barring some other substance that can provide viscosity in that environment, i.e. hydrocarbons on Titan.

Silver ralph

I reckon the Moon has more to do with plate tektonics than the oceans. The crust being heaved up and down twice a day must have a hellavan impact on crustal cohesion.
R

John Boles

Question – ! Okay, you know how the moon’s orbit has slowed over the eons (moon slowly farther from earth) due to tidal drag. Has the earth also moved farther from the sun? Would this explain the faint young sun paradox? Have all the planets slowly moved farther out over the millions of years? Any astronomers out there?

Technically, the tidal effects of the Moon on the Earth accelerates the Moon, thus increasing the distance between the two. Additionally the spinning of the Earth decelerates to insure an energy balance.
..
http://eclipse.gsfc.nasa.gov/SEcat5/secular.html

Thank you Joel for that bit of insight. I am embarrassed I did not see it sooner. It is so obvious now.

I read somewhere that Earth-Moon would eventually become tidally locked like Pluto-Charon, but apparently that would take far longer than the life of the Sun. Anyway, what would happen to Earth’s climate if a day were just a few hours longer? Talk about “extreme weather!”
It might be a good idea to mount giant rocket motors around the equator to ensure rotational velocity does not decline beyond some “tipping point.”

verdeviewer July 22, 2015 at 10:54 am

I read somewhere that Earth-Moon would eventually become tidally locked like Pluto-Charon, …

This is incorrect. The tides subtract energy from the earth’s rotation and add half that to the moon’s orbital energy. This slows the rotation of the earth and pushes the moon further away and slows it down. (The NASA page that calls this an “acceleration” is incompetent science writing, if we assume it isn’t just incompetent science.) However, getting back to verdeviewer’s point, the earth can push the moon all the way to infinity without the earth’s rotation slowing enough to get tidally locked to the moon. When this (never will) happen, the earth’s day would be about 55 hours long.
BTW, the other half of the energy lost by the earth is a net loss due to frictional heating. The human energy usage in the 1970s was twice that lost by tidal friction, and would be many times more now. So tidal energy is most definitely NOT “renewable”.

richard verney

Early in Earth’s history, the length of a day was only about 4 to 5 hours. The rate of rotation has slowed dramatically such that it is now about 24 hours.
As the moon retreats, the length of a day will gradually increase.
The rate of rotation of a planetary body has a major impact on its conditions.

Since the Moon’s orbital velocity around the Earth slows down as it moves into a higher orbit, what is this acceleration of the moon about.

Stan Vinson

Before you move an object into a higher orbit, you have to accelerate it. This acceleration increase the kinetic energy of the satellite which then coverts this new kinetic energy into potential energy by moving to a higher orbit. After the acceleration it’s orbital radius increases, and it’s velocity decreases to keep the sum of kinetic and potential energy constant.
This is one reason why an elliptical orbit with high eccentricity has the orbiting object moving faster at perigee and slower at apogee.

Ron House says: “(The NASA page that calls this an “acceleration” is incompetent science writing, if we assume it isn’t just incompetent science.)

The NASA page is correct in calling it an acceleration.
Any time you apply a force to a mass you are “accelerating” it (Remember F=MA ? )

For example if you put a weight at the end of a rope, and swing it round and round to show how centripetal force works, the weight is at constant velocity, but undergoing constant acceleration to follow a curved path.

cgh

The sun has heated up over time because of the buildup of impurities (elements other than hydrogen) in the Sun, requiring higher temperatures to maintain fusion.

Jquip

Wut. Obviously the Sun doesn’t create higher temperatures to get the fusion it has an ego-driven desire for. And given the stock notion you’ll see tossed around everywhere, the Sun’s heat is a consequence of fusion, not the other way around. So I’m completely baffled as to what you’re attempting to convey here.

Menicholas

The fusion was ignited in the core by the heat of gravitational contraction. One fusion ignited, it pushed back against the contraction, and a steady-ish state was reached, with the gravitational contraction forces balanced by the fusion heating/expansion forces.
This state will exist until the sun burns through the hydrogen in it’s core, and it’s mass will determine where in lies on the main sequence, how long it will reside there, and where, on the Hertzsprung -Russel diagram, it will go next. Our star will pass into it’s red giant phase when the hydrogen it the core is used up, and the hydrostatic equilibrium it maintained for about 8-10 billion years is disrupted. The stability of a star on the main sequence, and at a mass of the sun, is considerable. And how much energy it radiates is not a function of temperature alone, and surface brightness is not the same is core temperature in any case. The sun could be cooler, but larger, and thus deposit more energy to the Earth. The core will not get significantly hotter until the lack of hydrogen causes core contraction and helium burning commences. We will not last long when that show begins.
(On a “personal favorite” object of interest note: Just be glad we do not live a lot closer to Eta Carina, and hope that it does not produce a gamma ray burst. Wolf-Rayet stars may do, but it is uncertain in this case. It seems we are not in line with the axis of Eta Carina, but if we were, and if it did produce a gamma ray burst…even at 2700 light years, it would flash fry everyone and everything on the half of earth facing it, and could be the equivalent of a Hiroshima sized bomb on every square mile of the Earth.)

george e. smith

I think the sun is actually powered by gravity, which sucks. So long as you have enough mass of Hydrogen (any species), you will eventually get fusion reactions; which will stave of the gravity suction for a while.
We don’t have near enough hydrogen on earth to build a gravity suction reactor.
And the coulomb force blows instead of sucks, and that is inherently unstable.
g
I think that means nyet on earthly controlled (continuous) fusion.

Gary Hladik

“Have all the planets slowly moved farther out over the millions of years?”
According to the Nice Model, the orbits of the giant planets may have changed substantially since their formation:
https://en.wikipedia.org/wiki/Nice_model

scarletmacaw

John, the Earth has moved further from the sun over the 4.5 billion years because the sun is continually losing mass both through conversion to energy and through the solar wind. However, the effect is small, not enough to explain the young sun paradox, although every little bit helps.

Leo Morgan

Tidal effects from the sun also move the Earth away from the sun.
The tidal effect slowing the Earth’s rotation is converted by conservation of angular momentum to increasing distance between Earth and Sun. I don’t know the exact distance- the earth/moon system is separating at 1 and a half inches per day, but Lunar tides are twice as powerful as solar tides..
However I don’t know if adding this effect to the others you mention is especially significant. I’d love to see the numbers.

More modelling BS? Yep. The real world isnt 1s and 0s in silicon chips…

So the late early bombardment (or was it the early late bombardment?) kneaded our mantle, massaging it into tectonic activity. Extraordinary speculations need extraordinary evidence. Of course, there is none, but fun to think about nonetheless.

LeeHarvey

Neat idea… but wouldn’t uranium (and any other heavy radionuclides) sink to the middle of a molten earth?
Yeah, the potassium would float, but only potassium 40 has a reasonably long half life, and unless we detected huge outgassing of argon from the Moon or certain asteroids, I’d say that we still have most of our potassium 40.

cgh

Indeed, that’s where most of the earth’s uranium inventory is located. Radioactive decay is what’s kept the earth’s core liquid for the past 4.5 billion years.

Jquip

Ah, see now, this is part of the problem of modern science that is rife throughout things like Climastrology. We have estimated the age of the universe on the basis of various things, none of which are testable as such. And from that we’ve stated what the temperature of the Earth should be, which it isn’t. From which we estimate the amount of radioactive product that must be in the inaccessible and untestable Deep Earth (Hansen call your office.) From which we then state that since the Earth contains an estimate of whatever quantity of radioactive whatevers, therefore the age of the universe is… Each of the estimates is used to correct each of the other estimates such that they all hang together consistently. But calling it an ‘estimate’ is a little optimistic. As we certainly aren’t validating any of these things.
The consequences of which are statements such as: The Moon has no molten core, it’s too old. And then, surprise, it in fact does. Not much of one mind, but there you have it.
Lets do ourselves and the integrity of Science a favor. It’s not a ‘fact’ unless you can, and multiple people have, demonstrated it with experiments. Not estimates, experiments. And let’s ensure that a chain of provenance is always kept for all things. If P is clobbered together out of some idea of Q, then we cannot turn around and correct Q on the basis of P. As that’s just correcting Q on the basis of itself.

cgh

This question was debated starting in the 19th century. Stored radiation of heat would long since have produced a much smaller core with a much thicker crust. Radioactive decay explained how the earth’s core retained its high temperature and much larger volume that would otherwise be the case. And this statement:
“We have estimated the age of the universe on the basis of various things, none of which are testable as such”
is simply incorrecdt. Of course they’re testable. And they have been tested by observation. The problem is that the different observations conflict.

Jquip

cgh:

Radioactive decay explained how the earth’s core retained its high temperature and much larger volume that would otherwise be the case.

This only follows if we already know the age of the universe, or some minimum bound on it’s youth.

Of course they’re testable. And they have been tested by observation.

Yes, I’m perfectly well aware that there’s a fondness about for calling an ‘observation’ a ‘test.’ But that hardly makes it so and why I said ‘testable as such.’ Consider one of the key notions around sorting out cranks from science. It is common for cranks to let you observe their over unity energy machine, but not test it. You may look, but you may not touch. You may observe, but you may not test.

The problem is that the different observations conflict.

Different observations can hardly conflict with one another. They simply are. However, any one or more observations can conflict with a given theory. If there were no errors in the observation or its interpretation, then the only error is the theory itself. Until you sort this out, the rest of your education in the Scientific Method will need to wait.

george e. smith

Well why would the Uranium sink to the bottom ?? After all, the gravity at the center of the earth is zero, not some huge number that attracts heavy stuff. The deeper you go, the lower that gravity gets. So nothing is crushing anything, at the earth’s center.
g

“Well why would the Uranium sink to the bottom ?? After all, the gravity at the center of the earth is zero, not some huge number that attracts heavy stuff. The deeper you go, the lower that gravity gets. So nothing is crushing anything, at the earth’s center.”
This is just wrong! This is like saying that a submarine at neutral buoyancy can go as deep as it wants in the ocean and not have to worry about being crushed. There may be no net gravitational force at the center of the earth, but you still have the weight of 3,500 miles of rock pressing down on you from all sides even tough you yourself are floating weightless.

george e. smith said “Well why would the Uranium sink to the bottom ?? After all, the gravity at the center of the earth is zero” .
But the gradient is maximal .

Gamecock

Time for a REAL SAVE THE PLANET! movement. Earth don’t need it; Venus does.

Could Ceres be put on a collision course with Venus at just the right trajectory to put some spin on her?

menicholas

First we will need to drill the three big finger holes.

Andrew Harding

When the global warming scare first came to light, I believed it until some “scientist” said that if we did not stop burning fossil fuels Earth would end up like Venus because of the amount of CO2 in the atmosphere. This did cause me some worry until i decided to check it for myself.
“The density of the air at the surface is 67 kg/m3, which is 6.5% that of liquid water on Earth. The pressure found on Venus’s surface is high enough that the carbon dioxide is technically no longer a gas, but a supercritical fluid.” Wikipedia,
I realised that if temperatures increased so much that CO2 was lost from the oceans and limestone broke down to CaO and CO2 (which only happens at 848 Celsius anyway!) there would be a problem, until I then thought that all this CO2 was in the atmosphere in the first place and that did not cause Armageddon!
The whole AGW “theory” (in my view it is only a hypothesis) must be wrong! If I am missing something here, I would be grateful, if someone could let me know

Venus is hotter than Earth due to more mass in the atmosphere.
The evidence is that after adjusting for distance from the sun the atmospheric temperature is similar to that of Earth at the same pressure.

Exactly so.

Show me the equations .

“The only respite from the heat on Venus is to be found around 50 km into the atmosphere. It is at that point that temperatures and atmospheric pressure are equal to that of Earth’s”
from here:
http://www.universetoday.com/14306/temperature-of-venus/
but they don’t appreciate the implications of that fact.
and although this article:
http://www.datasync.com/~rsf1/vel/1918vpt.htm
discusses the viability of viruses on Venus it does show some relevant charts.
Although I don’t agree with Harry Dale Huffman on many matters he is dead right on this:
http://theendofthemystery.blogspot.co.uk/2010/11/venus-no-greenhouse-effect.html

Stephen , I know that it is claimed that at some height in the Venusian atmosphere the observations apparently match Earth . But I want to understand it . And for me that requires being able to compute it — which for me means to express the relationships succinctly in an APL ( at this point , my own 4th.CoSy ) .
Thus , to me , it remains just an interesting observation until I see and understand the equations and can derive it quantitatively to observational accuracy .
The classical quantitative relationships I assert have been and can be experimentally demonstrated and should be in any highschool physics curriculum .

I also disagree with Harry on the absorption / convection aspect but that does not detract from the calculation he presents.

Bob,
Stephen and Harry are just confusing themselves. The mean temperature at the 1 bar level in the Venusian atmosphere is ~339K. On Earth, the equivalent temperature (at the surface, at 1 bar) is 288K.
http://www.datasync.com/~rsf1/vel/1918-4a.gif
http://www.datasync.com/~rsf1/vel/1918-3b.gif
Yes, Venus is closer to the Sun, but it still absorbs a lot less solar energy as heat than what Earth does: 163 W/m2 vs. 239 W/m2. What Stephen and Harry leaves out is simply global albedo – Venus: 0.75, Earth: 0.3.
So Venus is hotter than the Earth by 51 degrees at the same atmospheric pressure level, even though it receives only 68.2% of its heat from the Sun. Go figure!

Kristian,
The albedo difference and the insolation difference are both dealt with by convective adjustments within the atmospheres which is why the ratios noted by Harry (and the ‘old’ pre radiation theory science) still apply to those planets with atmospheres where we have been able to ascertain the vertical temperature profile.
http://www.public.asu.edu/~hhuang38/mae578_lecture_06.pdf
“Radiative equilibrium
profile could be unstable;
convection restores it
to stability (or neutrality)”

Kristian , Thanks for the data ; Hockey has supplied critical equations . The temperature curve I would believe is the one that turns back towards the 328k equilibrium temperature of a gray ball ( flat spectrum ) in Venus’s orbit . That’s simply the temperature related by the StefanBoltzmann equation to the total energy impinging on a point in the orbit . Any difference from that from that as one descends in the atmosphere then is attributable to the absorption=emission spectrum of that atmosphere .
And the minimum of the curve would indicate that Venus is substantially more absorptive=emissive in the IR than its extreme albedo with respect to the solar spectrum .
However , the 184.5 or whatever NASA misleadingly labels Venus’s “black body” temperature is a useless inexcusably crude step-function approximation assuming Venus’s absorption=emission spectrum jumps to 1.0 at longer wavelengths . This is inexcusable when I am sure far more accurate measurements of Venus’s full spectrum are available . The fact that the atmosphere is apparently transparent at radar frequencies shows it’s not simply opaque black . At those frequencies , it is the absorptivity=emissivity of the surface which matters .
These emendations may seem small , but the total variation this statist useful hysteria is about is on the order of the 4th decimal place , a few 10s of a percent . There is no way you will ever understand such small phenomena if stuck on 2 digit crude ( and biased ) approximations when data are , or should be , available .

Stephen Wilde July 24, 2015 at 1:27 am
“The albedo difference and the insolation difference are both dealt with by convective adjustments within the atmospheres which is why the ratios noted by Harry (and the ‘old’ pre radiation theory science) still apply to those planets with atmospheres where we have been able to ascertain the vertical temperature profile.”
Er, no. Of course it isn’t “dealt with”. It is completely ignored. If it’s “dealt with”, that is, included, there is no fit, and hence Huffman’s great “discovery” is shown to be nothing more than an expression of the man’s profound confirmation bias.

usurbrain

How do the computer models factor in the effect that the lack of a magnetic flux, which would shield Venus from the solar winds striping away the Hydrogen and Oxygen and other gases from the higher atmosphere? Why is the fact that Venus has no magnetic flux never addressed in the feeble AGW explanations justifying the effect that CO2 has on the Earths temperature based upon the Temperature on Venus?

Mustread: Bullock & Grinspoon, The recent evolution of climate on Venus, Icarus 150 (1) 19-37
http://www.boulder.swri.edu/~bullock/Homedocs/vclime.pdf

Billy Liar

Well, that’s a massive house of cards.

Ancient astronomers and ancient oral histories from around the world — in areas and cultures that had zero interaction — all describe Venus as a stupendous comet.

CaligulaJones

Ironically, the best math teacher I had was very much into Velikovsky. I would have liked to have been in the teacher’s room when he ran into the best history teacher I ever had, and who had, shall we say, another opinion on Velikovsky.

cba

well even a broken clock can be right twice a day. therefore it’s not out of the realm of possibility that velikovsky could be right once in his lifetime.

I think that our moon is the reason why Earth is unlike Venus. But that’s a long story involving:
http://www.imcce.fr/Equipes/ASD/preprints/prep.2002/venus1.2002.pdf
and a few more thoughts that the authors missed.

The “scientists” crafted a very nice creation story. What religion are they doing this for?
By the way, I can’t find anyplace where gravity and the mass of the earth’s atmosphere vs. the same on Venus are mentioned. Really? The weight of the atmosphere makes no difference?

FerdinandAkin


“Erupting volcanoes release greenhouse gases from deep inside the planet and regular eruptions help to maintain the habitable climate”

Well, there goes any chance of them scoring a follow-on grant for further study.

I highly recommend the book Rare Earth: Why Complex Life Is Uncommon in the Universe (2000), by Peter Ward, Donald E. Brownlee.
It’s thesis is that simple forms of life may be quite common in the universe, but the development of Complex Life, not necessarily intelligent life, is probably much rarer than we thought just a couple decades ago.
The first argument, that simple life is that we have found simple life forms is some incredibly hostile environments such as deep sea volcanic vents that depend upon chemosysthesis. We have found bacteria inside rocks such as shales. Extremophiles that live in hot springs. Such discoveries make the finding of single cellular life on other bodies in just our own solar system a real possibility worth scientific investigation.
But the study of astronomy, astrophysics, paleontology, geology, biology, also lead to the conclusion that the condition that allowed the development of trees, dry land on a waterly planet, and animal life require conditions very unlikely to develop.
Most of the galaxy is hostile to life. A planet needs to be in a stable orbit around a stable star, in the “habitable zone”. The planet needs to have plate tectonics. It needs to be sufficiently large to retain an atmosphere, yet not so large that it becomes a gas giant. A large moon helps the planet maintain a stable axis with mild seasons. A rapid day-night cycle helps. You need all this stable enough for evolution to do its job. Rare conditions indeed.

joel

In an infinite universe, everything is not only possible, but likely.
Hitchhiker’s guide to the galaxy.
Think about it. The attraction between protons and electrons and all fundamental particles has to be just “right” for matter to exist. What are the chances of that happening? The multiverse concept is very likely true.
So, I would expect there to be many thousands of worlds with complex life in our galaxy. Not intelligent life as we understand it (human). Intelligence is highly over-rated and, as we have seen, soon leads to self-destruction through technology.

jorgekafkazar

Or through politics.

Tom in Florida

Sir Fred Hoyle and The Beryllium Bottleneck.

kcom1

” as we have seen, soon leads to self-destruction through technology”
Actually, we haven’t seen that.

bob boder

100% otherwise you wouldnt be here to ask that question

With untold billions of suns in our galaxy, with billions of galaxies, my thoughts would be that Earth like planets abound.

That depends on what you mean by “Earth-like”.
Earth-like in Mass? certainly
Earth-like in Habitable zone? yes many.
Earth-like in a stable orbit? Well that rules out half the galaxy.
Closer to the core the density of the stars make it a sure thing that one will pass close enough to another to jiggle the harmonics of any once-stable planetary system. One close encounter every 100 million years and you get repeated mass extinction events. We have survived a couple of them — the end of the Permian was a close call and it *probably* wasn’t a close encounter with a stellar neighbor.
So Earth like in Mass AND in a Habitable zone FOR a billion years…. The odds are getting longer.
Mind you, none of the previous condition preclude simple life. As Michael Crichton wrote: “Life will find a way.” Who knows what lie beneath the ice of Europa? The color bands of Jupiter may owe some of their existence to the biological waste products of scores of genus of simple life creatures.
Complex life, on the other hand, takes time for evolution to do its work. It need a place without gamma-ray bursts, solar variability, and dozen other environmentally hazardous astrophysical influences to destroy the handiwork of evolution.

Menicholas

There is a well known calculation multiplying each of the mentioned requirements (or what we might suppose are requirements) and then calculating the number of systems that have earth-like planets.
The final number is large.
The question then, now, has become: If this is true, then where the heck is everybody?
Funny thing about questions…until one knows the answer, one really has no idea whether they are even good questions, much less what the answers will turn out to be.
Our assumptions may be wrong, or we may just be less important than we think…or, there is no such thing as a warp drive engine, and space and time are very big…VERY BIG.
That may be the only real answer we need.
What hope does an earthworm in London have of finding a mole cricket in Indonesia?

george e. smith

Maybe so. Doesn’t mean ANY of those billions have life. Life is as improbable, as the number of earthlike planets is huge. Zero times infinity can still be zero. (or anything else).

Matt G

The biggest difference by far that is the main reason is Earth 1 atm, Venus 90 atm. Mentioned earlier at 1 atm on Venus the temperature is similar to Earth.

Asteroid bombardment, bombschmardment. The thing is we both got hit very early on by Mars-sized planetesimals but we took a glancing blow which actually spun us the right way and gave us a nice big fat moon, whereas Venus ended up spinning the wrong way. Hell on Venus followed from there.
Pointman

jorgekafkazar

Interesting. Is Earth the only planet in the solar system that spins “the right way?”

It’s not the “handedness” but the speed of revolution. How many hours long was the day in the Mesozoic era and what was already the effect of it? What will eventually happen to our spin and why? Follow up question, what happens when you spin up an iron core?
Pointman

Now here’s where probability and statistics come in handy: what are the chances that a collision would stop Venus dead in its tracks? or just a tiny bit backwards? or with resonance with the earth’s orbit? It seems almost as Velilkovskian as claiming a serendipitously circular orbit. Isn’t it more likely that a Venusian ocean or atmosphere slowed it down and stopped it, with the help of a big solar tide? –AGF

Reading skills Mr Foster, we’re not talking orbit here but spin, but I rather think you’re doing the modern version of spin in wilfully misinterpreting my comments. Velikovsky, who a low blow. Cicero: “If you don’t have a good argument, attack the plaintiff”.
Pointman

What the hell do you think I’m talking about? Resonance with the earth’s orbit? 3:2? That’s rotation. Rotation! And don’t take it so personal–I know you’re just spouting the consensus. But it’s a statistically incompetent consensus. The tides have to be invoked even with the questionable collision hypothesis–it’s a matter of degree. Since the history of the Venusian atmosphere and possible ocean is unknown, the collision hypothesis is an unneeded complication, not capable in itself of solving the problem. Do you think Mercury also slowed down via collision? –AGF

george e. smith

Why would statistics tell you anything about something that may not have happened at all, let alone enough times to get a good statistical sample to analyze.
g

Mike Maguire

The article/link below is intended to support the theory of “Intelligent Design”.
Whether you believe in that theory or not, it’s mind boggling to think about the hundreds of factors, many that are extraordinarily rare, that had to be just right for us to be here, reading and posting on WUWT at this moment.
http://www.godandscience.org/apologetics/designss.html
What would be the equivalent odds of flipping a coin and getting consecutive heads for instance?
Something on the order of flipping 1,000 consecutive heads, which has odds of 1:2(1,000th power) or ~1:10(301th power)
The actual number/odds for the coin flipping to heads 1,000 times in a row is: 1:
10715086071862673209 484250490600018105614 0481170553360744375 038837035105112493 612249319837881569 585812759467291755 314682518714528569 231404359845775746 985748039345677748 242309854210746050 623711418779541821 530464749835819412 6739876755916554394 607706291457119647 768654216766042983165 2624386837205668069376
………….of course that probability could be much less or much greater since we don’t have enough information to accurately estimate the statistical odds for the occurrence of most factors………but you get the point.

joel

The multiverse concept seems very attractive.

Menicholas

Not to me. What are the odds we would be in the right universe of the multiverse?
About the same as the random chance of us being here in the one single universe?
Inventing something that there is no proof of, no way to test for, and that solves nothing is a lazy man’s way out of wondering about things, IMO.
Why wonder about it if the answer one settles on, is the sophistry ad hoc explanations, or of deciding all things are equally possible, so everything is inevitable?

george e. smith

Why ??

Intelligent design is not a legitimate theory. It is an attempt to sneak creationism into schools through the pretend science back door, as found by Delaware courts.It is fully debunked as a misunderstanding and misapplication of evolutionary principles. Used the eye as the ID example in ebook The Arts of Truth.

Jquip

Yes and no. We cannot state that Intelligent Design is not appropriate to Science, nor that it’s not being used by science. At present Monsanto intelligently designs organisms every day. Likewise, forensic genetics are used routinely in biowarfare programs to highlight whether or not a given strain of a pathogen was intelligently designed or not.
What we can state is that because we can show intelligent design, it does not follow that all organisms were designed through all time. But the same problem adheres to the current consensus theory of Evolution. For we can show random mutations currently. But that hardly means that we can show that all organisms were constructed by random mutations through all time.
The problem here is not the current experimental results and engineering practices. It is the origin myths themselves. But as both origin myths have the same argument in favor, and the same epistemic veracity, then we cannot call one an issue of religious creation myth, but not the other. Either neither is, and so both can and should be taught. Or both are, and so neither should be taught on the public dime in nations such as the USA.

Tom in Florida

So if the universe has expanded and then contracted 10715086071862673209 484250490600018105614 0481170553360744375 038837035105112493 612249319837881569 585812759467291755 314682518714528569 231404359845775746 985748039345677748 242309854210746050 623711418779541821 530464749835819412 6739876755916554394 607706291457119647 768654216766042983165 2624386837205668069376 times, it would only take one of those expansions to be right for intelligent life to evolve and contemplate the question. The next question is: which expansion are we in?

Jquip

The one we’re in.

Menicholas

The current one. Which is the only one that maters, and the only one we know for sure is not a figment of someone’s imagination, The Matrix notwithstanding.

Gamecock

The United States has 600,000 doctors to deal with the problems of its Intelligently Designed humans. Some intelligence.

Dawtgtomis

I find it interesting that Mars appears to have had it’s surface scarred and partially ripped away by plasma arcing. Was it once like Earth before a close encounter with a charged object?
http://www.plasmacosmology.net/scars.html
It seems as time goes by we find less and less similarities in the individual planetary “experiences” over the aeons while sharing a common heliosphere.

schitzree

I choose to believe Mars had an earth like environment before the Martians fought a huge planetary war with weapons that make our nukes look like fireworks. ○¿●

Is it just me or do others find that running models and drawing conclusions about an uranium/potassium stripping impact event without any actual observations other than: ” the layer that should have been there isn’t” can’t be classified as “science” much more than a group of guys sitting on the sofa passing a bong and one saying to the others: “yea man what if elephants could fly” Wow man.

Billy Liar

It’s not just you. But, hey, in brings in the paycheck.

Ray Boorman

+1

These articles about how Venus came to be what we see today are garbage. They first of all ignore the widespread, global reports by pagans that Venus arrived in human-historical times as a comet (the feminine attribute derives directly from the comet’s hair). But, far worse than that, there is NEVER ANY MENTION OF THE FACT THAT THE VENUS PIONEER DATA WAS CORRECTED TO REFLECT A GREENHOUSE WARMING HYPOTHESIS.
See original snapshots at https://plus.google.com/108466508041843226480/posts/hKf2QRETTAy.
The only people talking about this are the plasma cosmology folks, so please realize that there’s a price to pay for filtering out their own posts on this site.
Even Plato is clear that a human-historical catastrophe occurred …
From Plato’s Dialogues at https://books.google.com/books?id=6IJEAAAAIAAJ&pg=PA367&lpg=PA367
“Phaethon, the son of Helios, having yoked the steeds in his father’s chariot, because he was not able to drive them in the path of his father, burned up all that was upon the earth, and was himself destroyed by a thunderbolt. Now, this has the form of a myth, but really signifies a declination of the bodies moving around the earth and in the heavens, and a great conflagration of things upon the earth recurring at long intervals of time”
(Notice that Plato is unwittingly describing a debris field that would regularly return to the earth after an initial catastrophe — even though Plato has no idea what gravity or a debris field actually is …)
And, to make sure that everybody understands the meaning of the ancient myths, he further states:
“All of these stories, and ten thousand others which are still more wonderful, have a common origin; many of them have been lost in the lapse of ages, or exist only as fragments; but the origin of them is what no one has told”
I don’t know how Plato could be any clearer:
The myths all originated with a planetary-scale catastrophe.

You’re supposed to put “sarc:)” or something like that. But we know you can’t be serious. –AGF

scarletmacaw

The collision which created the moon wiped out about 3/4 of Earth’s atmosphere. The lower surface pressure resulted in lower temperatures, and allowed liquid water. CO2 dissolved in the oceans and formed carbonates, further lowering the atmospheric pressure. The Earth also gets half the sunlight received by Venus. All of these factors combine to make Earth a lot different from Venus.

paqyfelyc

I guess you just cannot get attention nowadays without some sort of “OMG things COULD be so WORSE” …
Funny thing with Venus is, everyone is told that it is much hotter than Earth thanks to double solar irradiance and hellish greenhouse effect. Whereas in fact, because of its 0.9 albedo, Venus has (according to NASA’s “venus fact sheet”) a blackbody temperature 70 K LOWER than Earth (184 K Vs 254). It is horribly COLD (not hot !) out there.
I wonder …
Is it not because it is so cold, that atmosphere is so heavy, making surface so hot ?
funny paradox, if true. what you think ?

James at 48

More scientific rationale for Rare Earth. Rare Earth at least partially explains why most of the “evidence” of Extra Terrestrial Advanced Lifeforms is found on the likes of “Coast to Coast AM.”

Bloke down the pub

This hypothesis is based on the belief that the Earth was subjected to a greater bombardment than was Venus. The objects involved in the bombardment would have been in orbit around the Sun and as Venus is so much closer to the Sun than the Earth is, I can see no scenario where the Earth would have been impacted more heavily.

There is support here for the proposition that the heat at the surface of Venus is attributable to atmospheric mass held within a gravitational field and irradiated by an external source.
Yet I have been involved in many arguments here when regular contributors argued to the effect that it is not atmospheric mass which causes planetary surface temperatures to rise above S-B.
Interesting.

oeman50

I am getting ready to disappear in a cloud of blue steam. ( No apologies to Hansen)

usurbrain

It also seems strange to me that the “rocky” planets were originally and always “rocky” planets. Since all planets were supposedly made from an accumulation of the matter in the disk around the Sun, WHY would the inner planets NOT also have originated by all of the matter in the position in the disc that they were located? Thus all planets would have been gaseous at first, and then, over billions of years the inner planets would have lost large portions of their gases making up the planets and leaving a “rocky” planet.

Ray Boorman

maybe the gravitational attraction of the sun ensured that more dust & rocks moved to the inner parts of the disk, then formed rocky planets, while most of the lighter gases stayed in the outer portion & became the gas giants?

menicholas

The Rocky planets are much better than the Apollo Creed planets. Ask anyone.

rgbatduke

Personally I think that the only relevant unlikely event in the Earth’s history is the collision that bound the moon. That collision would have completely altered the composition of the Earth, and IMO probably took a large fraction of the early atmosphere of the Earth off with it.
It is this atmosphere that really differentiates the Earth and Venus. The atmosphere of Venus has a surface pressure of 90 atmospheres. The outermost portion of that atmosphere has to radiate as much energy as it receives, which determines the temperature, more or less, at its cloud tops. As a result of this high density (and its composition, mostly CO_2) the troposphere on Venus extends all the way to 65 km, roughly 10x higher than Earth’s, and it has to be balanced at a proportionally higher greybody temperature at the cloud tops since there is basically no direct radiation loss from the surface. There is no stratosphere on Venus — it goes straight to the mesosphere.
The lapse rate, OTOH, continues all the way to 100 km — 10x that of the Earth — and drops temperatures from over 700 K to under 200 K before turning over, where the Earth has a stratosphere that warms from a minimum temperature well above 200 K before dropping again in the Mesosphere and warming again (irrelevantly) in the thermosphere.
IMO the only reason Venus isn’t conducive to life is that it has way, way too much atmosphere, and tends to lose both O2 and N2 before either one can build up into an atmosphere like Earth’s with CO_2 constantly recycled into bound carbon and oxygen. I agree with the top article that the magnetic properties are important as well — having a strong magnetic field definitely alters the way the solar wind strips off atmosphere at the very top as well as protects the surface from excessive radiation — and suspect that this too is related to the moon-forming collision and its aftermath as much as anything else — but I’d bet “life would find a way” if somebody stripped Venus of 90% of its existing CO_2, allowing it to develop a stratosphere and cooling the surface to where liquid water might accumulate at least at the poles. It might help to take e.g. Europa and drop it onto Venus and wait a billion or so years and see what happened, or to scavenge a dwarf-planet’s worth of large (> 10 km) comets from the Oort cloud and drop them all onto Venus one at a time, blowing away most of its existing atmosphere and releasing a huge cloud of free water to reflect heat away with its high albedo until the surface had time to cool to the greatly reduced ALR to the much lower tropopause.
But we needn’t worry about the Earth becoming “like Venus” unless and until we could increase the total mass in our atmosphere by an order of magnitude or more, and there simply isn’t the raw material or any reasonable process that is going to make that happen.
rgb

rgbatduke said:
“But we needn’t worry about the Earth becoming “like Venus” unless and until we could increase the total mass in our atmosphere by an order of magnitude or more, ”
So is it mass that makes the Earth’s surface 33K warmer than S-B ?

Jquip

S-B is predicated on unobtanium by design. It is used as a mathematically and existentially ‘pure’ starting point for the rest. And for which if we find anything that violates S-B, then we know that Thermodynamics is as bunk as Phlogistons.
To claim that the Earth is 33K warmer than S-B requires that you give up at least one of:
1) Thermodynamics
2) The propriety of the model for charateristic temperature of a sphere orbiting an (effictively) point souce.
3) The propriety of the model for determining the average temperature of Earth.

Jquip , That 33k number is meaningless red herring useless in any computation . It is not the temperature of a grey , flat spectrum body in our orbit and it obscures the important fact that a gray ball , no matter how light or dark , comes to the same equilibrium temperature , about 278.6 +- ~ 2.3 degrees from peri- to ap- helion , Any difference in temperature is proportional to the 4th roof of the ratio of absorptivity=emissivity wrt the sun’s spectrum , and absorptivity=emissivity wrt the insignificant thermal spectrum of the rest of the celestial sphere . See http://cosy.com/Science/HeartlandBasicBasics.html for the computations including the assumptions creating the irrelevant 33k meme .

Jquip
The Earth’s surface is warmer than the S-B equation predicts but the Earth as a whole when viewed from space is not.
The difference (whether it be 33K or some other figure) is accounted for by surface kinetic energy locked into convective overturning which maintains the hydrostatic balance of the atmosphere as here:
http://www.public.asu.edu/~hhuang38/mae578_lecture_06.pdf
Thus:
“Radiative equilibrium
profile could be unstable;
convection restores it
to stability (or neutrality)”
The convective adjustment occurs without a change in surface temperature unless there is increased TOA insolation or a greater portion of TOA insolation reaching the surface provided atmospheric mass and the strength of the gravitational field remain constant.

Stephen , thanks for the link . I’ve bookmarked it .

Jquip

So you’ve given up 3). No worries, keep it under your hat as a challenge to others that haven’t thought about the issue.

bob boder

Why dont we paint a basketball the right color gray and put thermometer on it and launch it into space and make it rotate once every 24 hours? Then we can once and for all measure what temp the earth should be with out an atmosphere.

Bob , see my comment at July 22, 2015 at 9:49 am . This physics is older than relativity and was abstracted from broad experimentation in the 19th century . It is certainly no more difficult than the high school PSSC physics I had half a century ago .
But it would be extremely therapeutic to see it replicated today . It is clear that many posting here , much less any alarmist blog , have never learned even these most basic non-optional equations .
It would be useful to demonstrate them in both the brilliantly simple and affordable manner of the PSSC curriculum and most spectacularly by sticking well spectrally calibrated ball out the window of the space station . ( I don’t understand why engineers in satellite heat budgeting are not more active in these debates . )
When I moved from Manhattan to Colorado , the first thing I did becoming active in this battle for rationality was a “Mr Wizard” style experiment with painted ping-pong balls , http://cosy.com/Science/warm.htm#PingPong , to confirm my , literally childhood , sense of the most essential physics wasn’t just nuts .

rgbatduke

It makes it 33 warmer than the greybody temperature, which is not exactly S-B. It isn’t “mass” per se that does it, either — it is atmospheric density, the adiabatic lapse rate, and greenhouse gases all working together that does it. But I’ve explained this maybe four times on two or three different threads in the last couple of days on WUWT and I don’t have the energy to explain it again on yet another thread.
rgb

RGB , we are about 10 degrees warmer than the 278.6 of a gray , flat spectrum ball in our orbit . That is the only number useful in computations .
The 33 degree number is produced by a crude unjustifiable hypothetical step function spectrum assuming a average absorptivity=emissivity of 0.7 over the bulk of the solar spectrum , but an absorptivity=emissivity of 1.0 ( black ) over the longer wavelengths . Here’s a plot showing the computations :
http://cosy.com/Science/AGWpptHypotheticalSpectra.jpg

The 95% of the missing universe is not dark matter, it is charge, the recycling of charge from the sun enters from the poles. It discharges from the equator in the band +30 to -30 degrees north and south. This is the Earths internal heat. It is also the missing part of the puzzle in physics besides the missing part of the universe.

george e. smith

Well I don’t know what a S-B gray body spectrum or Temperature is, I only know what a fictitious BB spectrum or Temperature is, and incidently that BB is required to be isothermal, which it cannot be, unless it has infinite thermal conductivity as well.
So calculating what earth’s Temperature is “supposed” to be is an exercise in futility.
The Temperature of the earth is at all times, exactly what it is supposed to be; no more, and no less.
g

calculating what earth’s Temperature is “supposed” to be is an exercise in futility

By Kirchhoff ( & Stewart , building on Ritchie’s experiment ) the temperature of a gray , ie : flat spectrum , body , no matter how dark or light , will come to the same temperature as a black body — which simply calculated by summing all the radiant energy impinging on it .
That simple minimal computation explains 97% of our estimated temperature .

There’s a reasonable quantity of CaCO3 which at one time would have contributed a significant amount of CO2 in the Earth’s atmosphere

This article is basically bunk because it deals with plate tectonics as if the plates were floating around on an Earth of constant diameter. It has been conclusively proved that the Earth is expanding in diameter.
Websearch You Tube for videos on “expanding Earth” and you will see that the Earth’s sea bottoms contain very precise measurements of Pangea’s expansion through sea-floor spreading over time, including the directions of the spread.

menicholas

Whaaaa…?
I suppose they missed the part about subduction on the opposite margins of the plates.

TimC

Apropos of not very much at all, this reminds me of a question in my first year maths exam at uni which went very much as follows: “Assuming (if this were possible) that the Earth instantaneously disappeared from the solar system at some point of time, what would then happen to the Moon”? Answer – the Moon would wobble for a while about at first, but soon settle down into (effectively) exactly the same orbit as that of the (former) Earth. So: Earth and Moon are really dual planets, rotating about one another and, together jointly, about the Sun.
But Earth and Moon of course have very different climates and, yes of course, Earth is a pretty habitable place. How did we get so lucky? For myself I’d say essentially pure chance: but with enough stellar systems in the universe thankfully it had to happen somewhere. But I very much doubt we can be the only ones …

Jaakko Kateenkorva

To my knowledge no one has contested Émile Clapeyron’s pV = nRT. Because AGW cult seems to upscale laboratory experiments to planetary scale as a standard procedure, how much carbon homo sapiens should theoretically burn to even approach Venus-like temperatures on Earth?
PS. Because carbon is 4th most common chemical element in the our Galaxy and only the 15th on Earth (by mass), we may need Scott to beam Kranken Mare here for the project.

KevinM

From the University of British Columbia: lucky … evolutionary path … early in its history … early loss … evolution … early formation … create the Earth … events … differentiate Earth … over geological time … evolved so differently … billion-year-long swings … initial composition of a planet … evolution … circumstances that make Earth.”

chris moffatt

Is there some reason to actually believe that the early bombardments of Earth and Venus were quantitatively different other than hypothesizing it was so makes their desired result?
I’m getting the faint whiff of models here.

kcom1

“Venus is in a climate catastrophe”
Seriously?
Catastrophe to who? Who’s suffering?
Venus is what it is.
Is Mars in a climate catastrophe, too?

kcom1

Follow up:
Was Earth in a climate catastrophe when it was putatively stripped of 3/4 of its atmosphere? You would think so. Or did that solve the putatively existing climate catastrophe?
What’s the opposite of “be careful what you wish for”? “Be grateful what you didn’t wish for”?

Yes, Mars is in a major catastrophe. According to NASA it contains 30 times more CO2-ice than initially presumed. It has major difficulty kick-starting positive feedback loops.

Bruce Cobb

Correction; we Skeptics live on planet Earth. Hard to say what planet (or even universe) Warmists live on.

“With less impact erosion, Venus would cool episodically with catastrophic swings in the intensity of volcanic activity driving dramatic and billion-year-long swings in climate.
“We played out this impact erosion story forward in time and we were able to show that the effect of the conditions governing the initial composition of a planet can have profound consequences for its evolution.””

It appears to be a restatement of the theory that Venus has periodically resurfaced itself volcanically. This is obvious to practitioners of science since Venus has no craters, or very few, compared to most of the moons and planets and asteroids in the Solar System.
In this case, the “impact erosion” knocked off the layer of earth which would have made it resurface itself with planet-wide volcanic floods, just like Venus:

“…Earth’s first crust, which was rich in radioactive heat-producing elements such as uranium and potassium, was torn from the planet and lost to space when asteroids bombarded the planet early in its history.”

They could be getting a little closer to the truth when they say that some of earth’s crust has been partly lofted into space. It would not surprise me if an occasional meteorite was actually a terrestrial rock returning to us; rocks from Mars are collected from Antarctica all of the time.
It is not really a very peaceful neighborhood here. You can make all the rules and models you want but the sun and asteroids are not always going to obey them.

This little bombardment knocked off the crust
This little bombardment deposited the ocean water
This little bombardment cleared the stage for mammals
And now we are all snug and safe except for the ghgs from agriculture, cattle, and personal transportation.

Not to mention the Squidgy Bombardment, which, in the Nebular Hypothesis, assembled the planets in the first place.

richard verney

Venus, with a considerably denser atmosphere, incoming meteors/comets would get burnt up far more than they do here on planet Earth (or on the moon that has no atmosphere).
It may well be the case that most incoming material gets burnt up,, or breaks up into smaller parts so one may well not expect to see as much in the way of impact craters on Venus.
So it could well be the case that the lack of impact craters is not evidence for volcanic replenishment of the surface.

Where do they get these people????
Venus is the way it is because it has 96 times more atmosphere than Earth. The composition of that atmosphere is irrelevant! The ‘work’ done on that mass by gravity raises both the pressure and temperature of its atmosphere at its solid surface. This is standard physics. No other fairy tale explanation is needed. No greenhouse effect. Why is this so hard to understand?

Because it’s wrong!

Show me your equations .

I don’t see anything other than the most basic Stefan-Boltzmann relationship which will produce the 328k gray body temperature in Venus’s orbit . I don’t even see the equations for the dependence of radiative balance on spectrum ( color ) .
I see no equations for any additional parameters .

Bob,
What additional parameters do you need and why ?
The observed, measured ratio is enough to make the point is it not ?

Any of those factors which are a function of radius .

Dear Moderator, this comment seems to have been lost?
hockeyschtick Your comment is awaiting moderation.
July 22, 2015 at 7:19 pm
No, it is not wrong. Mathematical derivation of equations which perfectly describe temperature profiles of Earth, Venus, Triton, & all other planets in our solar system with thick atmospheres:
http://hockeyschtick.blogspot.com/2015/07/new-paper-finds-increased-co2-or.html
Same basic atmospheric physics were used to calculate the 1976 US Standard Atmosphere, without one single radiative transfer calculation, and entirely on the basis of mass/gravity/pressure/density. Trace CO2 was completely discarded from their model since it was determined to have negligible effect.
http://hockeyschtick.blogspot.com/search?q=1976+US+Standard+Atmosphere

I’ll have to study your links . While clearly there is a gravitational energy well to a planet , it intuitively seems far too little to account for the temperature gradient of Venus . In deed , Venus and Earth are very different in the manner in which they are heated . The Earth is , of course heated from the surface causing strong convection . Only about 3% of impinging solar energy reaches Venus’s surface . Thus in a first approximation the effective surface at which radiative balance between its spectrum as seen from the outside and that of the sun is high in the very reflective clouds . Within that boundary the divergence theorem says average energy density will match that calculated for that surface .
Unfortunately it will be some time before I look at these equations because my priority is bringing my open 4th.CoSy APL informed vocabulary in Forth to the point where I can express your equations as succinctly as you have written them so they will run on arbitrary data on any current or future hardware .
Incidentally , Alan Guth has a brief but convincing explanation of why gravity is a negative energy in a short appendix in his book The Inflationary Universe . It is appealing that the sum of gravitational and thermal energy is the quantity which is balanced . Perhaps that is what your equations do .

Bob,
It isn’t just the movement up or down in relation to the pull of gravity. For gases it is also the extent to which the gas molecules move closer together or further apart under the gravitational influence as they rise or fall relative to the centre of gravity.
That is where the bulk of the mechanical KE to PE or PE to KE exchange comes from.
When you bring that into the equation the temperature of the Venusian surface is fully explainable.

I will be looking at Hockey Schtick’s links when I have time . He provides equations .
But my priorities are my ( approximately ) MidSummer party the first Saturday in August ( anyone along the Front Range is welcome ) and some recursive “stack frame” vocabulary to enhance my 4th.CoSy‘s ability to express such equations and apply them over a sphere .

rgbatduke

Because it is wrong. Work is done on mass by gravity only when it changes height. Gravitational compression can indeed be a source of “heating” — in a gravitationally collapsing protostar, or maybe even in star-wannabe Jupiter. Not so much for the Earth’s atmosphere. The adiabatic lapse rate is what you are trying to describe, and it isn’t maintained by the “work” done by gravity, it is the result of the adiabatic expansion and compression of air that is uplifted or downfalling due to ordinary convection, due to buoyancy. And that in turn is caused by heating or cooling of the gas by something else, not by gravity.
Gravity is not a source of energy for the atmosphere. It is a bank where energy from other sources — almost entirely from the sun, ultimately — can be stored and recovered. But the source of atmospheric heat is pretty much The Sun.
rgb

rgb said:
“Gravity is not a source of energy for the atmosphere. It is a bank where energy from other sources — almost entirely from the sun, ultimately — can be stored and recovered”
Gravity itself is not the ‘bank’ because gravity has no ‘substance’ which can carry such banked energy.
Instead the ‘bank’ is atmospheric mass which, when lifted up within a gravitational field stores what was previously heat in the form of kinetic energy as potential energy which is not heat.
That kinetic energy is then recovered in the subsequent descentt.
The recovered kinetic energy in descent cannot warm the surface directly but instead reduces convection beneath the descending column which allows continuing insolation to heat the surface beneath higher than S-B predicts.
The additional kinetic energy at the surface cannot then be radiated to space because it immediately gets taken up in the next cycle of convective uplift.
The same parcel of kinetic energy at the surface cannot simultaneously be radiated to space AND engaged in maintaining the hydrostatic balance of atmospheric mass suspended off the surface against the force of gravity.
Energy cannot be in two places at once or perform two distinct processes at once.

“That kinetic energy is then recovered in the subsequent descent”

Oppps….

You forgot something.

Whenever some air rises due to heat, there is an equivalent volume of air that has to descend to take it’s place.

Joel,
That is implicit in my account.
Once the first convective overturning cycle completes, a quantity of stored PE is then locked permanently into that cycle and cannot escape to space.
From then on all KE taken up from the surface is matched by KE returning to the surface in a never ending loop and that is why the surface is warmer than S-B. No GHGs needed.
RGB seems to think that the relevant PE is simply the sort of PE stored by lifting a solid or a liquid up against gravity which is a relatively small figure.
Since gases are far more compressible than solids or liquids the PE that they acquire during uplift is mostly derived from the molecules moving apart rather than from the mere uplifting of their mass against gravity.
As the gas molecules move up into a region of lower pressure the moving apart takes up energy in the form of PE and in the process reduces the vibrational activity of each molecule which results in a reduction of KE and thus cooling.
Gases which decrease density always bcome cooler (vibrating less) and gases which increase density always become warmer (vibrating more)
It is the relationship between density and molecular vibrational activity which is most relevant rather than simple height above the surface. This is a special feature of gases which is why we need The Gas Laws.

“a quantity of stored PE is then locked permanently into that cycle and cannot escape to space.”
….
I don’t think that is correct. The effect is a zero sum game. The energy used to move mass up is recovered in the heating due to compression of the downward moving air that replaces the volume in the updraft.

Joel,
It is only a zero sum game after the first convective overturning cycle completes.
At that point just as much energy is taken upwards as is returned downwards in a never ending loop for as long as the atmosphere remains suspended off the surface.
During the first convective cycle the energy taken upward was drawn from radiation leaving to space so from space the Earth would temporarily appear to be at 255K less 33K = 222K.
At the end of that first convective cycle the Earth from space would settle at 255K but you still have that extra 33K (or whatever) sitting at the surface holding the mass of the atmosphere off the surface in hydrostatic balance.

rgb says gravity doesn’t do thermodynamic Work on Earth’s or the Venutian atmosphere (due to adiabatic compression/expansion). Sorry, but this contradicts basic atmospheric physics known at least since Maxwell’s 1872 book Theory of Heat, and which proposed the basis of the barometric formulae, Poisson relation, and the 33C gravito-thermal (not radiative) GHE. Here’s slides from a basic atmospheric physics course that explain Work done by gravity via adiabatic compression/expansion:
http://hockeyschtick.blogspot.com/search?q=adiabatic+work+thermodynamics
See also:
http://hockeyschtick.blogspot.com/2014/11/the-greenhouse-equation-predicts.html

Joel said:
“There is a significant difference between the environment at 1 atm pressure on Venus versus 1 atm pressure on Earth”
Why is that ‘significant’ if temperature and pressure are similar at 1 atm ?
That simple fact shows that it is atmospheric mass and not radiative characteristics which controls temperatures and pressures within planetary atmospheres.
Other features of the surrounding environment are irrelevant.
The only factors that influence surface temperatures are atmospheric mass, the strength of the gravitational field (which controls surface densitry) and the prortion of top of atmosphere insolation absorbed by both surface and atmosphere by conduction and convection.
Any radiative imbalances that develop are dealt with by convective changes that prevent surface temperature changes.
For a detailed explanation as to how that works see here:
http://hockeyschtick.blogspot.co.uk/2015/07/erasing-agw-how-convection-responds-to.html
The second diagram is especially pertinent.

“Why is that ‘significant’??

Simple.

On earth there is a solid/liquid surface below the 1 atm point. There is no such surface on Venus at that altitude.

Inbound radiation behaves differently when it hits the solid/liquid surface at 1 atm on Earth as opposed to the transparent volume beneath the 1atm altitude on Venus.

“Inbound radiation behaves differently when it hits the solid/liquid surface at 1 atm on Earth as opposed to the transparent volume beneath the 1atm altitude on Venus.”
But yet it makes no difference to the relationship between temperature and pressure which rather proves my point 🙂
Convection adjusts to correct for any radiative imbalances.

” But yet it makes no difference to the relationship between temperature and pressure ”

The relationship breaks down at the 1 atm level.

Any pressure higher than 1 atm makes the comparison between Earth and Venus invalid.

Mike McMillan

Still confused about the adiabatic lapse rate I see.
Maintained by gravity. An upward moving gas molecule loses speed, and thus temperature, to gravity. A downward moving molecule gains speed and thus temperature.

Correct.
If radiative characteristics serve to introduce a radiative equilibrium then convection changes to negate it:
http://www.public.asu.edu/~hhuang38/mae578_lecture_06.pdf
The proof is that the temperature and pressure within the atmospheres of both Earth and Venus (and other planets) is similar after adjusting for distance from the sun.
Harry Dale Huffman’s calculation is correct and he cannot be discredited on that point just because one might disagree with him on other points.

Harry Dale Huffman’s calculation is incorrect due to a massive problem in his thinking. There is a significant difference between the environment at 1 atm pressure on Venus versus 1 atm pressure on Earth. Below the altitude of 1 atm on Venus there is a lot of atmosphere where radiant energy can dissipate, many km of additional CO2. On Earth below the 1 atm point there is solid surface. You cannot compare the two because it is an “apples to oranges” comparison.

Joel D Jackson: The point is that the *overlapping* portions of the T/P curve are very similar between Earth & Venus, despite huge differences of atmospheric composition. True for all the other planets with thick atmospheres in our solar system as well (Robinson & Catling in Nature). Magellan mission shows T/P curve very close to Earth’s 1976 US Std Atmosphere overlapping portions, & US Std Atm completely excludes CO2 & radiative calculations from their model.

I’ve been aware of it being standard physics since schooldays in the mid 20th century. Only in recent years as it been ignored and replaced with the defective radiative theory of gases.

I think that the importance of the Earth’s magnetic shielding from the solar and cosmic rays radiation is grossly underestimated.

MarkW

Where did they get the idea that the early earth’s crust was full of transuranics? Being heavier, those elements would have mostly sunk to the core while the earth’s surface was still molten.
This alleged bombardment erosion would have affected all of the inner planets.
The reason why the earth has a thin crust is that a Mars sized planet crashed into the earth some 4 billion years ago. The collision ejected most of the crust which formed the moon.
The two cores combined giving us a larger than average core, combined with a thinner than average crust.

That impact erosion theory is not likely. What distinguishes us from Venus is plate tectonics: we have it but Venus does not. With active plate tectonics radioactive heat is constantly vented by plate boundary volcanism. Absent plate tectonics, heat just piles up beneath the crust. In-plate volcanoes form and excessive heat eventually so weakens the crust that it breaks up into giant slabs. These sink into the interior and an entirely new crust is created. Its atmosphere is a product of these giant volcanic eructations and not a result of an ocean boiling away as some climate scientists like Hansen have hypothesized. On Venus impact craters are not eroded and from crater counts it has been determined that the existing crust is no more than 500 million years old. It is likely that these repaving incidents happen every 300 to 600 million years on Venus. If it is the same age as the earth there may have been as many as eight or ten such episodes in its past.

Peter

Venus is not so dissimilar from Earth as it looks on first sight. Just strip Venus atmosphere from CO2, imagine it as storing it to limestone CaCO3… Look what will remain:
16800x10e15 kg of N2 (Earth 4270x10e15kg), 72x10e15kg of SO2, 33.6x10e15 of Argon (Earth 47x10e15), 9.6x10e15kg of water (Earth 1400000x10e15kg), 3.4x10e15 kg of Neon.
Mass of water comparing to Earth seems minuscule, but it is enough to cover whole Venus with 21cm deep ocean.
Let’s assume that Nitrogen/Oxygen ratio will remain same as on Earth 78/21% and some Oxygen remains in atmosphere. It will be 4523x10e15kg (21/78*16800)
Result will be total mass of atmosphere 21432x10e15kg (Earth 5500x10e15kg) with percentual content:
78% N2
21% O2
0.3% SO2
0.1% Ar
0.01% Ne
So we have 4 times more dense atmosphere than on Earth, with almost same composition and some water to run hydrological cycle.
I think only problem of Venus is missing life which did not strip Venus atmosphere of CO2 and stored it as limestone and Carbon.

Sublime.

rgbatduke

I don’t completely disagree with this, but I think the much more dense atmosphere also created the surface temperatures that made life capable of stripping out CO2 and reducing it to oxygen and not just limestone but other forms of sequestered carbon comparatively unlikely. I’m guessing its comparative dearth of water made a big difference as well — both because life probably requires free water or even free ice to start up (which in turn requires certain pressure/temperature ranges) and because oceans are enormous thermal sinks. The Earth’s ocean acts like an anti-greenhouse — 4 C on the bottom almost everywhere, warmer in only a very thin layer at the very surface (where even that is warmer). That’s the funny thing. At least 60%, maybe closer to 70%, of the actual surface of the Earth is at or very close to 4 C in temperature. If one averages the temperature over the mass of the fluid components of the Earth’s surface, I suspect that they are collectively much colder than 288 K. Even the land surface rapidly approaches the 10 to 14 C temperature that is supposedly the average once you dig below the surface — ten feet or more down, it is usually cave cool, and remains quite cool until you descend far enough to begin to experience the effect of insulation and switch from surface heating to heat flowing out of the interior as a primary source.
It sounds like Venus is remarkably hot everywhere in its interior, given its surface temperature.
If we had the money and the will, we could certainly do some very interesting things with Venus. The most interesting one would be to try to block sunlight from Venus altogether for a year or two. Try to cool it to where the CO_2 rained out on the surface, chilling it down but good. See if doing this would freeze it deep enough to develop a real crust, one that would last when the screen was removed. Partially remove the screen, let it develop (say) 1 atm of pressure, and see if one could get plants established that would fix the carbon and liberate the oxygen while letting it gradually warm. Drop a few dozen comets on it to bump up the water. Install a huge solar powered laser in orbit that is aimed to blow off its atmosphere (give it escape speed at the top) and run it for a few centuries to see if one can strip it down. Terraform the place!
It isn’t any more of a waste of money than carbon trading, and there is a whole world to reclaim if one can make it work. Mars would be fun to work on as well, but there the difficulty would be getting the raw materials for an atmosphere and (if possible) bumping up its mass so that it would last. One would have to drop whole moons into it and wait a few million years for it to cool down. Venus seems as though it could be a much faster project.
rgb

I find the closeness of the 277+ deep ocean temperature to the 278+ gray body temperature in our orbit an interesting datum .
A strong prima facie indication that Venus’s internal heat dominates is that its surface temperature appears to be nearly uniform over the whole sphere despite its year long day .

cba

Bob,
venus has an effective gb T of only 188K vs 255K for earth. Thats because its bond albedo is 0.90 already. It’s at 3/4 the orbital diameter of earth so the tsi is somewhat more but that albedo has a massive effect. you have some interesting terraforming notions but the biggest buggaboo is that rotation rate. no rotation – no magnetic field. it’s doubtlessly extremely hot inside and capable of one – if it could only spin up. trying to blow off the atmosphere from a big laser – cut idea – assuming it doesn’t launch itself outa orbit by it’s own beam but with no spin – the atmosphere is no mixed well vertically. it’s basically an ocean of co2 at the bottom and nearly 2 (earth) atmospheres of n2 floating on top – so you’d blow away the n2 before you ever made a dent in co2.
seems like pretty much a lost cause – better to colonize the asteroid belt, moon, and mars before wasting effort on venus. even mercury might be effort better spent. besides, in the long run, we need to get further away from that warming sun and when it finally goes, venus is going to be inside.LOL

gb T of only 188K vs 255K for earth

I’m sorry , but those are such irrelevant BS numbers . Doubly so if “gb” stands for “gray body” .
The gray body ( flat spectrum ) temperature in Venus’s orbit is about 328k .
If you want to discuss any other value , give me a measured full absorption=emission spectrum for the planet and I will tell you its radiative balance temperature .

cba

feel free to go check out the nasa fact sheet on venus. you’ll find its temperature at 184.2k

rgb said:
“It makes it 33 warmer than the greybody temperature, which is not exactly S-B. It isn’t “mass” per se that does it, either — it is atmospheric density, the adiabatic lapse rate, and greenhouse gases all working together that does it. ”
You don’t need greenhouse gases to do it.
Even without GHGs gravity works with mass to produce declining density with height. It is that decline in density with height that allows uneven surface heating (causing density differentials in the horizontal plane at the surface) to result in lighter less dense parcels of air rising above heavier more dense parcels.
Convective overturning inevitably ensues with no need for GHGs. There can be no isothermal atmosphere developing as long as there is uneven surface heating (inevitable around a sphere illuminated by a point source) and a decline in density with height.
Reducing density with height creates the lapse rate slope because work is done against gravity in lifting atmospheric mass and that converts KE at the surface to PE above the surface for a cooling effect.
The process is reversed in descent.
This is basic meteorology which is a specialised discipline from which one can learn that rising columns of air develop huge reserves of potential energy (PE).

Agreed with Stephen, including “you don’t need GHGs to do it,” and that a pure N2/O2 atmosphere would establish a GHE/temperature gradient (even greater than current atmosphere – calculations in my links above).
Maxwell, greatest physicist in history on the topics of heat & radiation said in his 1872 book Theory of Heat that the atmospheric temperature gradient (GHE) is due to dominance of convection over radiative-convective equilibrium, & atmospheric temperatures a function of pressure raised to a ratio of specific heat capacities. Carnot & Clausius also described the essentially the same gravito-thermal GHE.

Scott

Basically we are here because we are here, the odds are like drawing 4 of a kind 4 hands in a row, but it happened. With billions of stars it’s likely life started else where as well. I’m mean we have creatures at the bottom of the ocean.
In our solar system having 1 planet with life is incredible, not everyone gets 4 of a kind 4 hands in a row in 5 card stud.

No, it is not wrong. Mathematical derivation of equations which perfectly describe temperature profiles of Earth, Venus, Triton, & all other planets in our solar system with thick atmospheres:
http://hockeyschtick.blogspot.com/2015/07/new-paper-finds-increased-co2-or.html
Same basic atmospheric physics were used to calculate the 1976 US Standard Atmosphere, without one single radiative transfer calculation, and entirely on the basis of mass/gravity/pressure/density. Trace CO2 was completely discarded from their model since it was determined to have negligible effect.
http://hockeyschtick.blogspot.com/search?q=1976+US+Standard+Atmosphere

donald penman

This illustrates how climate science works, we have three things; what is, what isn’t and what might be. Every statement about greenhouse warming has to be qualified by “than it would have been” and how do we know how hot it would have been. The atmosphere of Venus is mostly carbon dioxide which is a greenhouse gas so why would it not have some effect on temperature as well as atmospheric pressure. If we were to take water out of earths atmosphere then it would seem to me that we would end up with a dessert climate where it was hot during the day but cold at night it would only be uniformly hot if we had the atmospheric pressure of Venus.

Menicholas

A dessert climate?
Must be Baked Alaska!