A provocative hypothetical question: What if the Moon was not there? Video follows.
This giant rock lights up the night and can even change colors. So what would we do without it? Would we all need night vision goggles? How would it affect the ocean tides? Our seasons? Or our sleep cycles? Or would the consequences be far more drastic?
As the closest celestial body to our planet, the moon exerts a gravitational pull that governs much of what happens here on Earth Take the sea, for example. If you like surfing, you can thank the moon when the moon’s gravitational pull tugs on our spinning Earth, the oceans respond, giving us high tides in some parts of the world, and low tides elsewhere.
…
The Earth would speed up it’s rotation, giving us days of six to eight hours long
Rotating at that speed, we would experience winds up to 480 kms per hour (300 mph). Birds and insects would have no chance of survival.
…
Earth’s axial plane would vary by some 10 degrees, causing dramatic shifts in seasons, and rendering our climate uninhabitable. Most crops would die with the drastic temperature changes. We’d experience the worst ice ages known to man, as huge glaciers from the north and south poles would encroach upon the Earth, covering everything except perhaps a small band along the equator.
Source script and more: https://insh.world/science/what-if-we-suddenly-lost-the-moon/
Some silliness here, but speculation is always good for brain exercise!
Shouldn’t such speculation be based on physics?
Here is a climate model that is partially driven by lunar tides:
Wilson and Sidorenkov, A Luni-Solar Connection to Weather and Climate I: Centennial Times Scales, J Earth Sci Clim Change 2018, 9:2 DOI: 10.4172/2157-7617.1000446
Abstract
Lunar ephemeris data is used to find the times when the Perigee of the lunar orbit points directly toward or away from the Sun, at times when the Earth is located at one of its solstices or equinoxes, for the period from 1993 to 2528 A.D. The precision of these lunar alignments is expressed in the form of a lunar alignment index (ϕ). When a plot is made of ϕ, in a frame-of-reference that is fixed with respect to the Perihelion of the Earth’s orbit, distinct periodicities are seen at 28.75, 31.0, 88.5 (Gleissberg Cycle), 148.25, and 208.0 years (de Vries Cycle). The full significance of the 208.0-year repetition pattern in ϕ only becomes apparent when these periodicities are compared to those observed in the spectra for two proxy time series. The first is the amplitude spectrum of the maximum daytime temperatures (Tm) on the Southern Colorado Plateau for the period from 266 BC to 1997 AD. The second is the Fourier spectrum of the solar modulation potential (ϕm) over the last 9400 years. A comparison between these three spectra shows that of the nine most prominent periods seen in ϕ, eight have matching peaks in the spectrum of ϕm, and seven have matching peaks in the spectrum of Tm. This strongly supports the contention that all three of these phenomena are related to one another. A heuristic Luni-Solar climate model is developed in order to explain the connections between ϕ, Tm and ϕm.
When a plot is made of the precision of these [lunar] alignments, in a frame-of-reference that is fixed with respect to the Perihelion of the Earth’s orbit, the most precise alignments take place in an orderly pattern that repeats itself once every 208.0 years:
0 × (28.75 + 31.00) + 28.75 years = 28.75 years ≈ 25.5 FMC’s
1 × (28.75 + 31.00) + 28.75 years = 88.5 years ≈ 78.5 FMC’s
2 × (28.75 + 31.00) + 28.75 years = 148.25 years ≈ 131.5 FMC’s
3 × (28.75 + 31.00) + 28.75 years = 208.0 years ≈ 184.5 FMC’s
A simple extension of this pattern gives additional precise alignments at periods of 236.75, 296.50, 356.25, 416.0, 444.75 and 504.5 years. The full significance of the 208-year repetition pattern in the periodicities of the lunar alignment index (ϕ) only becomes apparent when these periodicities are compared to those observed in the spectra for two proxy time series.
No, we should actually worry based on the climate science mandatory future worry algorithm. The law of conservation of angular momentum tells us that in fact, the moon is moving further from the earth over time, and that we will eventually lose it.
Earth and moon would settle into a stable system about 50 billion years from now, with the moon at its maximum orbit of some 47 days. Earth’s rotation would also then take 47 days, so one side of Earth will always face the moon.
But, just five or six billion years from now, the sun will go red giant. It might engulf both Earth and moon, unless its previous loss of mass means that our orbit then will lie beyond the edge of the inferno.
Decades ago, Isaac Asimov wrote an article for Astounding SF magazine (or perhaps Analog) that described how, over ages, the Moon would move farther from the Earth, and then closer and closer until gravity broke it up and the fragments became a ring like Saturn’s. Except, he said at the end of the essay, that process would take so long, that the Sun would explode and envelope the Earth before the process was complete.
What if…
Well, it would stop eco nuts from howling at night so we can finally get some sleep.
Read Seveneves by Neal Stephenson
Even if the Moon were to suddenly vanish, The Earth wouldn’t instantly increase rotational speed. It would gradually speed up, Pulling the atmosphere with it so very liely No 300 MPH winds. Currently the atmosphere is rotating at over 1000 MPH given that the earth is 24000 miles around and rotates once daily.
If the moon disappeared, the rate of rotation wouldn’t increase at all.
The earth’s rate of rotation gradually decreased over time as rotational energy was transferred from the earth to the moon. If the moon were disappear, that rotational energy would not be transferred to the earth, it would just be gone.
Exactly. If the Earth had never had a moon then it would still be spinning faster, because the moon has been slowing the Earth’s rotation, slightly, for a very long time. But if the Earth lost its moon it would not “speed up it’s rotation” at all.
Nor would the Earth “experience the worst ice ages known to man” due to larger seasonal changes. Larger seasonal changes are what bring an end to glaciations, it is smaller seasonal changes that bring an end to interglacials.
Milankovitch cycles change the breadth of seasonal temperature swings at the latitudes where it matters for glaciation: mainly northern North America and northern Eurasia.
When those seasonal swings increase it increases ice melt in the summers and decreases snowfall in the winters. (When temperatures are very low snowfall is greatly reduced, because the cold air cannot carry much moisture; it is said to be “too cold to snow.”) That causes ice sheets to shrink.
When the seasonal swings are reduced it decreases ice melt in the summers and increases snowfall in the winters. That causes ice sheets to grow.
When, due to Milankovitch cycles, the Earth’s seasonal swings are reduced to the point that the great northern ice sheets grow a little bit each year, by adding more snow in the winters than they lose in the summers, after thousands of years of ice sheet growth it adds up to a very large increase in planetary albedo, a positive feedback mechanism which amplifies the effect. Conversely, when the Earth’s seasonal swings are increased to the point that the great northern ice sheets shrink a little bit each year, as the ice sheets dwindle it eventually adds up to a large reduction in planetary albedo.
And CO2 not a thing to do with it. Oh My!!!!!
The green blob will tell you quite a different story.
Yes, that was the point at which I stopped taking this BS seriously as well.
Not even half thought out.
I’m 74 and don’t really care. Our life spans should preclude us from any worry about any of this nonsense. We have to live and survive whatever the planet throws at us. We can dirty the water, dirty the air but the rest is out of our hands. Knowledge can be interesting but……..
Yes, and the rapid rotation of the Earth was supposedly due the initial impact of a Mars-sized object which created the Moon in the first place. No impact means no Moon and a much lower rotation speed.
Jim
Finally a comment with some real insight. There was so much bs in this thread I quit reading and posted a simple comment at the end of all this. Looked again and came across yours. For everybody in this thread do the following.
Research the orbit evolution of mercury. Sun synced as much as orbit allows
Research the orbit evolution of venus. Inverted (slow retrograde) Sun synced orbit.
Then imagine earth had it not captured its moon….
Slow orbit
No way for oceans to develope, boiling on hot side, frozen on cold side
No mechanism to pull gases from atmosphere
Earth would look like Venus
Good point Mark
Bryan A – February 15, 2019 at 12:14 pm
Bryan, me thinks that you should re-consider your above statement.
Note: the atmosphere is not firmly attached to the surface. 😊
If we lost the moon the Milankovitch cycles would change and the precession cycle would get much longer, since it is depending on the gravitational pull of the moon and sun on the equatorial bulge. If the precesion cycle and the obliquity cycle were about o be equal then the Earth spin axis would enter the chaotic zone* as Venus has done, with extreme permutations. We would not be amused.
*http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.453.4737&rep=rep1&type=pdf
I agree. Without the Moon the climate of the Earth would be too chaotic, as the Moon stabilizes the axial tilt. We simply wouldn’t be here as we have required 540 million years of stable conditions to appear.
This is one of the things that make me so suspicious of the claims of many inhabitable planets out there. Ours is inhabitable due to a freak accident that provided the Earth with a metallic core and a huge magnetic field for such a small planet, protecting our atmosphere, and with a clearly outsized moon that has given us a stable climate hospitable to complex life.
Intelligent life might be a lot more scarce than we think. Our sun already has spent about half of the hydrogen in the core, and in about 50 million years more tectonic activity might be too low to produce enough CO2 to support plant-based trophic chains.
In a cosmic instant intelligent life will disappear from an extremely unusual planet.
IMO microbes are probably fairly common on other worlds, but large, complex multicellular heterotrophs and autotrophs, not so much.
Lacking a poweful magnetosphere, life might need to be sheltered by ice or rock to survive.
But simple life could probably endure more extreme and variable seasons.
I actually think this relates strongly to the Fermi paradox. Life is probably very common throughout the universe, but intelligent life is much less likely. This is evidenced by Earth’s 4 billion years of evolution before humans (and dolphins?) arrived.
Earth must have some very special characteristics and our large moon is probably one of them.
Depending on how you define “intelligent”, a lot of other animals, to include invertebrates, would qualify.
But still yes, no intelligent life for over 3.5 billion years after organisms first appeared on Earth some four billion years ago.
You say ” freak accident”…. or was it purposeful afterall? huh.
Earth’s magnetosphere isn’t all that freakish, since Mercury, Jupiter and Saturn also generate magnetic fields in their interiors. Mars’ field is far simpler and less extensive than Earth’s, although it might have been stronger when the Red Planet was young. Venus has no internal field, but the solar wind does induce one it its upper atmosphere.
Uranus’ magnetic field is strange, in that its magnetic poles lie even farther, much farther, away from its geographic poles than Earth’s. Neptune’s field is also tilted, though less dramatically.
The collision presumed to have caused Earth to have a large moon can however be considered a freak accident. Other solar system objects suffered large impacts after initially accreting enough mass from numerous smaller collisions to form spheres, such as asteroid Vesta and probably Mars. But those collisions didn’t produce such a large satellite relative to the body struck.
Earth and its impactor would have engaged in a gravitational dance before finally colliding. The gravity environment of early Earth permitted a large, competing planetesimal to form in its vicinity.
The Pluto-Charon system is perhaps an analog (however it arose) to the Earth-Moon system, although Pluto has other more distant moons as well. Not surprising since, unlike an official “planet”, it hasn’t “cleared its neighborhood”.
Summarizing magnetic field strength:
Ice giants: Strong.
Gas giants: Strong.
Mars: Vestigial, its probable original liquid core having cooled and possibly solidified.
Earth: Medium.
Venus: Possibly never had one, lacking an internal dynamo.
Mercury: Weak.
Jupiter’s big moon Ganymede also has an internal magnetic field.
Dunno how moon Ganymede’s magnetic field compares to Mercury’s, but both are weak.
Ganymede is 8% larger than planet Mercury, but only 45% as massive.
However the accidental collision might have given Earth a larger core, so the strength of our field compared to the weak to nonexistent fields of the other inner planets could regarded as freakish.
CO2 to the rescue!
Interesting video btw. Thanks!
when considered all what is said, if true the ‘intelligent design’ comes to mind, but not for me at this time.
How exactly do tides benefit surfers?
The only thing I can think of is that some beaches may only be surf able at hig tides due to submerged objects.
Have you never surfed the tidal bore on the Bay of Fundy? You don’t know what you missed!
So much nonsense, it’s hard to know where to begin.
As I said above, the disappearance of the moon would have no impact the earth’s rate of rotation, or on surfers abilities to surf.
The earth’s 23.5 degree tilt isn’t stable, it wanders quite a bit over time. However it takes millions of years for it to wander noticeably. The absence of the moon might make this wandering a bit faster and a bit more extreme, but it will still be way too slow for humans to notice.
Currents are determined by the amount of heat being pumped in by the sun and the earth’s rotation. If the moon plays any role at all, it’s a very minor one. There would be no dramatic slow down, and no dramatic change in climate. Heck, once you are more than a couple of hundred miles from the shore, the impact of oceans on temperature drops dramatically anyway.
If the moon were to disappear, oceans would adjust, but it wouldn’t be catastrophic. The max difference in ocean heights right now is the distance between high tide and low tide. With the loss of the moon, the oceans would adjust to a level that would be about half way between high tide and low tide. It would also take several days for this adjustment to be felt. Sorry guys, no massive tsunamis.
With no tides, the crap we put into the oceans right at shoreline would build up without the constant cleaning of the tides.
Ocean currents aren’t going away. Tides just move the same water in and out twice a day.
The Sun’s tidal effects are about 1/2 of the Moon’s. It’s why there are neap tides and spring tides. If the Moon wasn’t there, we’d still have tides—just not as big.
Jim
The truly disastrous effects to our world and life as we know it would play out over several hundred thousand to several million years, mainly obliquity shifts to extremes. The immediate effects would likely be minor as you note.
The biggest short term effect would be allowing more stress to build-up in tectonically active zones (fault lines between plates such as Pacific ring of fire) until the stresses are released in major cataclysmic earthquakes and volcanic ruptures, rather than a more steady, but lower energy releases as happens now under constant lunar tidal deformations.
I believe the Earth still has an active core (and I contend the only inner planet) due to the Moon.
Lucky lucky us.
We’d lose plate tectonics within 1500 years and without the churning of the moon’s gravity the Earth’s core would start to cool.
There wouldn’t be increases in stress, the stress would stop.
The Moon controls Earth’s atmospheric tides. Depending upon the phase of the Moon, noontime sun needs to penetrate varying thicknesses of atmosphere. This also means that atmospheric tides offer up differing amounts of CO2 within that atmosphere for noontime sun to penetrate. More atmosphere during atmospheric ‘high’ tides would also produce more ‘back-radiation’ than atmospheric ‘low’ tides, yet this is not being measured. Does it exist if it can’t be measured?
The Moon also affects Earth’s albedo through these atmospheric tides. Yet the Moon’s phase is not used in the derivation of the Earth’s expected temperature, why not?
That video is about as accurate as An Inconvenient Truth.
Hey! We watched “An Inconvenient Truth” with my physics classes. We were able to pinpoint four things that were scientifically accurate. Not bad for a 97 minute documentary.
We might not be here.
Tides may well be a significant factor in the creation of life.
Icepilot, the Moon may well be a significant factor in the creation of you. Keep in mind the orbital period of the Moon, and a human female’s menstrual cycle.
Isaac Asimov pointed out that women’s menstrual cycles fluctuate a little, and often line up with other women when living in close quarters. He thought this flexibility in timing would result in each woman’s cycle quickly lining up with the moon’s cycle, if the moon had any influence over her cycle at all. As he put it, that women’s cycles don’t align with the moon’s cycle means the moon must have no influence whatsoever.
SR
I have heard theories saying that the massive tides caused by a much closer moon billions of years ago might have created just the right environment for the genesis of life. And without life, the climate would be profoundly different.
Highly speculative, of course.
Like Miller’s Planet?
The video is quite deceptive and downright bogus in many of its claims.
It freely and casually mixes two very different scenarios:
– “What if we suddenly lost our Moon (vanished)?” (which is the title of the video) with
– “What if the Moon never existed?”
Those are two very different scenarios and after watching the video it is clear to me they mixed the worst things of the two scenarios to come up with a single-most alarmist scenario without any regard for scientific accuracy and/or uncertainty.
And then there were outright dishonest statements. The Earth would not suddenly begin to accelerate its spin if the moon disappear in an instant. That would violate the Law of Conservation of Angular Momentum. (1:13 mark in the video)
And in another part, the narrator admitted with just the Sun sans Moon, solar induced tides would be much weaker, but then about a minute later they were telling us the tides would be so strong and high “the oceans would rip towards the sun and causing catastrophic waves.” (2:05 mark in the video)
Just more Junk Science trying to act as credible, alarmist science to titillate a science-lliterate audience.
“Just more Junk Science trying to act as credible, alarmist science to titillate a science-lliterate audience.”
More like click-bait scientism designed to stimulate the amygdala triggering the FUD* emotions.
*FUD – Fear, Uncertainty and Doubt
At least there would be no lunatics.
😉
“What would happen to Earth’s Climate and Weather if we had no Moon?”
——————
Sorry, can’t resist it
As all mammalian species are Lunatic, we would not even be around.
Probably the life in this planet will still be mainly Jurassic…. 🙂
As per the length of the day in this planet without the Moon , “the message in the bottle”
from the Tirano-Rex has not been received yet… or maybe not properly translated yet,
to tell us.
No any Rosetta-Rex stone found yet… 🙂
Hope this no “wayyyyy tooo out of line”… 🙂
cheers
There was no shortage of Jurassic mammals.
As there is no shortage of cold blooded and egg laying species in today world.
Still there is even laying egg mammals there today still, and marsupials too.
But most probably Jurassic then was not a Lunatic world, me thinks.
cheers
“There was no shortage of Jurassic mammals.”
Sneaking out at night by moonlight to avoid being eaten by dinosaurs and other reptiles.
No moon, no moonlight.
Mammals would have struggled to survive unless they developed sonar [a few did]
Not all Mesozoic mammals were nocturnal. There were arboreal mammals, burrowers and insectivores, plus the surprisingly large beaver-like Castorcauda from the Middle Jurassic.
Nor were all Mesozoic mammals tiny, ground-dwelling or tree-dwelling, nocturnal animals similar to shrews, hedgehogs, treeshrews or tenrecs.
This view has been shown false by such Jurassic mammals as the armadillo-like, termite-eating Fruitafossor, the flying squirrel-like Volaticotherium and the beaver-like Castorocauda (largest known Jurassic and possbily Mesozoic mammal), and the Cretaceous predator of dinosaurs and other vertebrates Repenomamus, plus the small and spiny tenrec-like creature Spinolestes.
John
As today, nor all non-mammals are tiny, but still the biggest and most powerful over the lands and Oceans are mammalian (Lunatic 🙂 ) species, if I am not wrong.
And
We are having an argument over a “A provocative hypothetical question”… 🙂
Meant to be fun orientated, I think.
cheers
Sorry. I thought by Lunatic you meant nocturnal, rather than crazy.
Lunatic, as Moon behavior orientated, sensitive-responsive,
Like wolfs, or lions, or elephants, or man, “howling” at the Moon…
Productive and “aggressive” tempered behavior under the influence of Moon cycles, aka Lunatic…perhaps even erratic behavior influenced up to some point, at times…like Full Moon ones.
Moon cycles, influencing mood and physical variation behavior response…maybe even influencing the gender outcome in a pregnancy…maybe…just saying.
Don’t think that as put above, Lunatic will strictly necessarily mean neither nocturnal or crazy.
But that how I will put it in the context of our ongoing conversation.
cheers
Not just mammals are sensitive to lunar influences.
Yes, not just mammals are sensitive or responsive to lunar influence.
but mammals are the more and most than the rest.
More significant effect or influence in mammals…which makes mammals really considered as Lunatic, I think.
The mammals show a more significant impulse response to lunar influence, as far as I know, interesting quite more significant than the rest…which to a degree may actually deserve some head-scratching time, when it comes to the point of evolution and adaptation of species over time.
Just an angle that I think it must be not ignored.
cheers
Lunar related behavior of various animal groups, vertebrate and invertebrate:
http://nzetc.victoria.ac.nz/tm/scholarly/tei-Bio17Tuat03-t1-body-d5.html
Doesn’t mention amphibians, so here:
https://academic.oup.com/beheco/article/24/1/53/2261367
Nor birds:
http://www.nbcnews.com/id/26780904/ns/technology_and_science/t/full-moon-makes-birds-extra-energetic/#.XGd9XVxKjIU
Thank you John Tillman, for all your effort.
Very much appreciated… 🙂
thanks.
cheers
We like the moon!
Must be British, you can tell by the teeth.
The moon does not drive ocean currents nor make the 23 degree tilt stable.
According to George E. Williams the moon has played a fundamental role in establishing Earth’s obliquity and changing it over time.
Williams, G. E. (1993). History of the Earth’s obliquity. Earth-Science Reviews, 34(1), 1-45.
A relatively stable climate over the past 500 years appears to have been a fortunate consequence of the moon formation and presence.
Possibly for the past 4.5 billion years as well, to the extent that climate has been relatively stable, while ranging from maybe -50 degrees C to 25 degrees C and spiking higher (after the crust cooled, that is).
The moon doesn’t make the orbital tilt stable, it does however make it less unstable.
Good example of ‘stuff people will believe if it sounds sciency’ anyway.
Maybe a more relevant question would be, what would happen to earth’s climate if there were no green house gases in the atmosphere. Much more than you might think!!!
Winds and rain do work (in the Physics sense of the word). The energy for this work has to come from somewhere and it comes from the atmosphere, but how? Well the atmosphere is a giant heat engine in the Carnot sense. Solar energy is absorbed at the surface of the Earth and transferred to the atmosphere by contact at the surface, by absorption of radiation emitted by the surface and by evaporation of water. (This is the hot junction). At the top of the atmosphere (actually the top of the troposphere and lower stratosphere) energy is lost to space by radiation which forms the cold junction. The working fluid is the atmosphere itself moving from the hot junction to the cold junction – expanding in the process and then moving back to the hot junction being compressed in the process. The efficiency is defined by the temperature difference between the hot and cold junction – in this case 288K at the hot junction and about 215K at the cold junction. An absolutely classic Carnot cycle.
HOWEVER!! the atmosphere at the tropopause can only lose energy to space via radiation and the only species that can radiate energy are the green house gases. In fact, that is precisely the definition of a green house gas (One that can absorb and radiate thermal infrared energy between about 8 microns and 50 microns). So if there were no green house gases the upper atmosphere could not lose energy to space which means there would be no cold junction and thus no Carnot cycle, which means the atmosphere could not do work! That means there would be no convection, no winds, no net evaporation of water from the surface, no rainfall. Without rainfall there would be no land plants and thus no animal life on land. Now thats a pretty big change.
Of course one could argue that the poles would be a cold junction with the equator the hot junction. Nice thought but unfortunately the coriolis force due to the rotation of the Earth is a huge barrier to such a global circulation. As air moves from the equator to the pole it experiences a reducing radius of rotation which means to maintain angular momentum it has to speed up and that results in a centripetal force which pushes it back towards the equator. It is in fact why we have 3 circulations (the Hadley cell, the Ferrel cell and the polar cell). Also how would the atmosphere lose energy to the surface at the poles? Without GHG, radiation is out which leaves only conduction at the surface and maybe condensation of water at the poles. Conduction is too small to be significant and if its by water condensation, there would be no way for the water to return to the equator so all the oceans would end up as ice at the poles which would mean no oceans and thus after a while, no further water condensation at the poles so again no weather!!!!
So net effect, without GHG there would be no weather on Earth and at least no land life. Of course, with no evaporation and thus no condensation there would be no clouds, and clouds are the main source of Earth’s albedo. There would also be no dust since there would be no winds to maintain it. With a significantly lower albedo the surface would not be absorbing 243 watts/sqM on average but more like 330 watts/sqM corresponding to a surface temperature of about 276K or +3C. So maybe the Earth would be about 10C colder than it is today. A sobering thought – we should embrace GHG’s.
“if there were no green house gases the upper atmosphere could not lose energy to space”
All matter above absolute zero temperature emit radiation approximately as gray body or black body
No Dr Strangelove, gases which are not green house gases eg: nitrogen and oxygen do NOT emit radiation as a grey or black body. If what you say were correct, there would be no such thing as a green house gas or rather all gases would be green house gases which would make CO2 concentration a very moot point. It depends on the emissivity. Solid objects all have a non zero emissivity although some solid objects may have a relatively low emissivity for example, highly polished metal but gases which are not green house gases more or less by definition have a zero emissivity in the thermal infrared region.
Oxygen gas emission spectrum
Nitrogen gas emission spectrum
Emission spectra of gray and black bodies vary with temperature. All matter above absolute zero temperature emit radiation
I think you will find you are confusing thermal emission with electronic transition emission. The former comes from asymmetric vibration of the molecule which distort the electric field. In the case of CO2 the dominant vibrational mode of importance is bending. The vibration is excited simply due to the temperature of the gas hence thermal emission. But N2 and O2 are symmetrical molecules, vibration of such molecules does not distort the electric field and thus does not lead to electromagnetic emission. The latter involves an electron transiting from one orbit to another and atmospheric temperatures are far too low to excite that sort of emission. Plank’s law, the Stefan Boltzman law all relate to thermal emission and the green house effect is entirely due to thermal emission.
Kirchoffs law states that at any given temperature and wavelength the emissivity of an object must exactly equal its absorptivity. It is easy to show that if that were not the case it would allow net energy transfer from a colder object to a warmer object. So, if nitrogen and oxygen indeed radiated as black or even grey bodies they would also absorb as black or grey bodies at the same wavelengths. But that would mean the atmosphere would be opaque, they would absorb all the long wave radiation from the surface. So how could the atmospheric window exist? Further, nitrogen and oxygen together represent about 95% of the atmosphere and about 2500 times the concentration of CO2. If they radiated at anything like black or grey bodies why would they not utterly dominate thermal radiation transfers and if so what possible role is left for water vapour, carbon dioxide and other green house gases? If you believe oxygen and nitrogen radiate in the thermal infrared what exactly do you understand a green house gas to be? How does its behaviour differ from N2 or O2? Do you think it absorbs and emits at levels greater than defined by Plank’s law?
Planks law defines the thermal radiation at a given temperature and wavelength for a black body ie: one with an emissivity of 1. Emissivity cannot be >1 only less than 1 so Planks law defines the maximum possible emission at a given temperature and wavelength. Thermal emission at a rate exceeding that given by Planks law is not possible.
If you look at a spectrum of Earth’s emission to space (look at the Nimbus data for example), one can see the continuum curve as defined by Planks law showing the emission from the surface (which is close to a black body in the infrared) but overlayed on it are notches. The one at 14.7 microns is due to CO2 absorbing surface radiation and replacing it with radiation from the tropopause which is colder. The notch at 10 microns is absorption of surface radiation by ozone and replacing it with radiation from high up in the stratosphere which is colder than the surface (but warmer than the tropopause). At wavelengths below about 8 microns and above 15 microns the spectrum is very jagged due to absorption of surface radiation by the many lines of water vapour (the picket fence analogy). Now if N2 and O2 absorb and radiate in the thermal infrared, can you point out to me the lines due to these gases? If there are none it means N2 and O2 are not absorbing and if they don’t absorb they also cannot emit.
Mr. Hammer, both the RSS and UAH data sets on troposphere temperatures are derived from satellite measurements of microwave “brightness.” A major component of this is what is emitted by oxygen.
…
” The atmospheric components of our RTM rely on the most recent and relevant measurements of oxygen and vapor.”
..
Ref: http://www.remss.com/measurements/brightness-temperature/
..
Keith; yes oxygen does have thermal emission lines in the microwave portion of the spectrum (but not in the thermal IR region) and they are used for satellite measurements but the total energy involved is too small to have a significant impact on Earth’s overall energy balance. That can be seen by solving Plank’s law for the microwave region using a temperature of between 200K and 300K. At these temperatures the peak of the emission intensity is around 12 microns whereas the microwave region is more like 1000 microns. My original post was trying to show that without the GHG’s the heat engine driving weather on earth could not function, at least not to any significant degree.
1) the distinction between thermal infrared and microwave is arbitrary.
2) ” the total energy involved is too small to have a significant impact on Earth’s overall energy balance.” WRONG, because at 20% of the atmosphere, the emissions of oxygen are significantly as opposed to the emissions from a GHG that comprises 400 ppm of said atmosphere.
Keith, your point 1 as to the name being arbitrary is correct but the difference between 12 microns and 1000 microns is significant. At 200K -300K the difference in black body emission between the region between 8 and 50 microns vs the emisssion at around 1000 microns is very significant.
As to your second point, it sounds like you are suggesting that the emission is some how proportional to concentration. It isn’t quite like that. Once the line center saturates the emissivity at that wavelength becomes 1 and no further increase is possible. What does happen with increasing concentration is that the line broadens (this is because the lines are roughly gaussian in shape and each doubling of concentration is equivalent to convolving the absorption profile with itself. The result of convolving a gaussian with itself is a new gaussian with the same mean but a larger standard deviation ie: width). This gives the logarithmic response with concentration so often commented on. The increase between 400 ppm and 200,000 ppm is 500:1 or 9 doublings. However, I did a quick calculation of the emission intensity at 1000 microns vs the peak of around 11 microns and the emission at 1000 microns was about 1 million times less. Even 9 doublings is not going to make that dominant.
Mike, I agree, and you are totally correct to say: “Even 9 doublings is not going to make that dominant.”
…
However, you are incorrect to say: “the total energy involved is too small to have a significant impact on Earth’s overall energy balance. ”
…
There is a wide gap between the idea of “dominance” and “significance.”
”Now if N2 and O2 absorb and radiate in the thermal infrared, can you point out to me the lines due to these gases?”
Pointed out here:
https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2012GL051409
hello Trick; I looked at your web reference. It cites a total of 0.28 watts/sqM from O2 plus N2. If I read it right the same paper at the end gives a table which shows the total for all ghg of 101 watts/sqM. By the way it does not point out any specific absorption lines for N2 and O2. The N2 and O2 impact is probably due to weak overtone bands but ignoring that; if we accept their numbers, N2 and O2 contribute about 0.28 percent of the total.
Going back to my original thesis that weather on earth is driven by the atmospheric heat engine cycling between the warm surface and the cold tropopause(Carnot cycle) and that this is turn relies on ghg to create the necessary cold junction (tropopause), I think your data proves the point quite conclusively. After all, without the ghg the energy loss from the atmosphere would be about 400 times lower. The tropopause would be barely colder than the surface which means the Carnot efficiency would be a far smaller fraction of something 400 time smaller to start with. Essentially no weather on earth.
”The tropopause would be barely colder than the surface”
With reduced IR active gas, the tropopause would still be much cooler than the surface due the lapse rate which would not change (much). There essentially would still be weather.
”By the way it does not point out any specific absorption lines for N2 and O2.”
See Intro.: [5] The collision-induced fundamental vibration-rotation band at 6.4 mm is the major absorption signature of O2 in the thermal infrared. Timofeyev and Tonkov [1978]
And: [6]N 2 has two major bands influencing the infrared radiation: the collision-induced roto vibrational fundamental band at 2400 cm^-1 and the collision-induced roto translational band at 100 cm^-1. In the atmosphere, the mid-infrared absorption of N2 was first observed by Susskind and Searl [1977].
Transcription error: The collision-induced fundamental vibration-rotation band at 6.4 micron is the major absorption signature of O2 in the thermal infrared.
Hi Trick;
You say the tropopause would still be cold because of the lapse rate. I disagree. Consider, below the tropopause is the troposphere which is warmer, above the tropopause (and lower stratosphere) is the mid and upper stratosphere which again is warmer. So the tropopause is surrounded by warmer regions. How does it remain cold? After all net heat cannot flow from colder to warmer without being pumped. The ONLY way the tropopause can remain cold is if it can pass heat to an even colder sink and the only colder sink available is space. That means it remains cold because it can radiate energy to space but without green house gases it cant do that.
So could it be cold simply because the gas rising below it is expanding and cooling adiabatically? Well yes, initially but where does this rising gas go having got to the tropopause. If it starts to sink it will warm up again as it gets compressed. For it to sink it first has to lose energy and without GHG it cant. So it stays where it is and in the process it blocks further air from rising up. Without a cold sink convection stops – this is after all the most fundamental aspect of heat engines and the carnot cycle. A heat engine must have a hot junction and a cold junction. Maximum efficiency in turning heat into work is given by (Thot – Tcold)/Thot. Without a cold junction one cannot turn heat into work. One can hardly deny that wind and rain (water elevated to higher altitudes) both represent work – after all we can turn both into electricity (wind and hydro power). The thing driving the work being done is energy from the sun so its more or less by definition a heat engine.
Sure if convection continues one needs a lapse rate and that implies a cold tropopause but since the tropopause cannot keep itself cold it warms up and the result is convection stops and the lapse rate disappears. The entire atmosphere equilibrates to more or less constant temperature. Without convection, evaporation of water from the surface stops – other than some evaporation during the day and recondensation as dew at night but since there is no wind there would be no transport from oceans to land so no rivers and no rain. During the day one would get some warming of the near surface air allowing it to rise a bit but during the night the air would be coldest near the surface since it can lose energy to space by conduction to the surface which can radiate to space so a temperature inversion and no falling air. Quite quickly the air well above the surface would get warm enough so that even during the day the was insufficient lapse rate for there to be any rising air. The atmosphere would equilibrate to a temperature close to the maximum surface temperature during the day. ie: no convection, the atmosphere could do not work and that would mean no weather.
Interested to hear your take on all this.
cheers
Mike H
”That means (tropopause) remains cold because (tropopause) can radiate energy to space but without greenhouse gases it can’t do that.”
Sure gases at the tropopause can do that Mike. The paper I just posted shows how/where/why N2,O2 radiate. And what’s more, all gases radiate. And above the tropopause Earth atm. is isothermal for about 9km (STP) because the gas becomes warmed from above not below so tropopause is not surrounded by warm air at the top, it is surrounded by same temperature air (generally, barring storms).
”If it starts to sink it will warm up again as it gets compressed.”
It doesn’t sink, the atm. is mostly hydrostatic, density horizontally stratified and no pistons inhabit the atm. to do the compressing anyway.
”So it stays where it is and in the process it blocks further air from rising up.”
Stays yes, but no blocking – if upward convecting air has enough CAPE initial velocity, the rising air blasts through the tropopause and cauliflowers out.
”since the tropopause cannot keep itself cold it warms up and the result is convection stops and the lapse rate disappears.”
Disagree for the above reasons. The troposphere atm. cannot be isothermal with reduced IR active gas and ideal -g/Cp (or environmental lapse) because the fluid in the troposphere is warmed from below in a gravity field, thus there will always be convection thus weather. Bouyant and mechanical convection would not cease, geostrophic winds, trade winds would still exist, & so would evaporation which depends on the state of the liquid not the state of the air above the liquid.
Thus the troposphere would not equilibrate to a temperature close to the maximum surface temperature during the day, convection would still exist thus the lapse, and the atmosphere could still do work limited by CAPE and that would mean weather.
Sorry Trick but I cant agree with much of what you wrote. You say the air doesn’t sink, that most of the atmosphere is hydrostatic. However the dominant feature driving weather on earth is the Hadley cell which features air rising at the ITCZ (intertropical convergence zone) – near the equator and sinking air at around latitude 30 North and South. This falling air creates a permanent band of high pressure at the surface at latitude +-30. Because the air starts off dry at the tropopause and is compressed and thus heated as it sinks, it is extremely dry when it reaches the surface. Most of earth’s deserts are located at around these latitudes for that reason. The outflow from the sinking air creates the trade winds on the equator side as it returns to the ITCZ. On the pole side it drives the ferrel cell and the polar cell air flows. On the pole side the outflowing air encounter rapid change in radius of rotation. While it starts off moving at more or less the same speed as the surface at latitude 30 as it moves to higher latitudes it ends up moving faster than the surface creating a west to east wind that increases in velocity as one moves poleward. hence the roaring 40’s the furious 50’s and the screaming 60’s. The air speed relatiove to the surface becomes so great around latitude 60 that centripetal force drives it upwards again creating the ferrel cell.
To suggest the lapse rate creates a cold tropopause (I know that’s not quite what you said but its more or less what you imply) is putting things the wrong way round. It’s the cold tropopause which creates the temperature differential with the surface that creates convection. The convection feeds energy into the tropopause and an equilibrium is reached where the rate of convection balances energy input with the energy loss to space and that defines the lapse rate.
A much simpler way of looking at the issue is: wind and rain represent mechanical energy- clearly since we can directly harness either to do work such as generate electricity. The energy source which fuels that is thermal energy from the sun. A system which converts thermal energy into mechanical energy is defined as a heat engine and the laws governing its operation are very well understood. In particular the second law of thermodynamics states that 100% efficient conversion of heat into mechanical energy is not possible. The system MUST have a hot junction where thermal energy enters and a cold junction where thermal energy exits, with the working fluid cycling between the hot and cold junctions. In this case the working fluid is the atmosphere and it cycles between the hot and cold due to convection, expanding as it rises and being compressed as it falls again (Hadley cell). In our atmosphere the hot junction is the surface and the cold junction is the tropopause. If the tropopause cannot lose energy (or at least no more than a very trivial amount of energy) how does the system lose energy to space? What becomes the cold junction? The work done is a result of convection – if the system cannot lose energy from a cold junction it cant do work. But convection represents mechanical work since we can intercept the convecting air with a windmill to generate power – indeed weather is the manifestation of work being done. The only solution is that there is no convection and no weather.
If convection and weather still occurs without GHG’s either it means the second law of thermodynamics is wrong (unlikely) or there must be another mechanism for Earth to lose energy to space from a cold junction. If so, what is that mechanism and where is the cold junction?
cheers again and I am enjoying this discussion
Mike H
”If convection and weather still occurs without GHG’s either it means the second law of thermodynamics is wrong (unlikely) or there must be another mechanism for Earth to lose energy to space from a cold junction. If so, what is that mechanism and where is the cold junction?”
This suggests a singularity as the IR active gases reduce. There is no mechanism to produce a singularity. All gases radiate, the outgoing emission spectrum would shift to regions where emission is possible so you just get a colder surface temperature, colder tropopause and weather changed by the reduced CAPE.
The formula for lapse shows it isn’t changed much, nonisothermality below tropopause and isothermality above for a great distance. Bouyant convection & mechanical Hadley circulation still exist, the mechanism that drives them is still operative. 2LOT and 1LOT are fine with all this, entropy would still be produced and there would be a new energy balance in/out.
Can’t quite agree with a singularity Trick. As the GHG reduces, the convection would weaken. Rainfall and clouds at the ITCZ would reduce and winds generally would drop. Eventually with further reduction the Hadley cell would simply gradually fade away. Without significant clouds or impediment for surface radiation to escape to space the albedo would drop to low levels, the insolation would rise from 243 watts/sqM closer to 343 watts/sqM but the surface would radiate freely to space. Its average temperature would drop to about +4C or about 10C colder than at present. Still have thermal equilibrium but no cold junction simply a surface receiving energy from the sun and re-radiating it back out to space.
While the upper atmosphere was colder than the surface there would be some convection but the heat energy would remain trapped in the upper atmosphere since it cant radiate away so that would rise until it equilibrated with the surface temperature when convection would stop. Which of course would happen extremely fast in any sort of geological time scale. Actually one could make an argument that convection would continue during transient high surface temperatures (eg: miday in summer) so that eventually the atmosphere would equilibrate at close to the highest such surface temperature so that for most of the time there would be a permanent temperature inversion with the atmosphere warmer than the surface. Such temperature inversions do occasionally occur now from time to time in localised areas and when they do, convection stops and we get very calm conditions. It would simply become world wide and continuous.
No singularity, just a fade out to total calmness as green house gas effects faded away. Yes the lapse rate does not change much with increasing convection but that is for a well established convection. As one goes to less and less convection the lapse rate will change more rapidly and near zero convection it will start to change very rapidly. It will become patchy with localised lapse rates significantly higher than the average (regions where convection still occurs) and these patches will become more and more rare until they finally disappear completely. Even now, the average lapse rate may be well established but localised lapse rates can vary considerably from the average, it is far form uniform everywhere. Think of thermals, updrafts and downdrafts.
”Eventually with further reduction the Hadley cell would simply gradually fade away.”
The maintenance of the energy of the general circulation would be largely unaffected. Frictional losses would be about the same while the net heating in the low latitudes and net cooling in high latitudes, a familiar feature of the general circulation, would still exist.
The surface would not radiate freely to space, there would still be an atm. IR optical depth though much reduced. The surface temperature would depend on the albedo change. The albedo would reduce with less humidity for less condensation (which depends on the state of the air), less clouds but increase due to increased surface snow/ice cover.
”the heat energy would remain trapped in the upper atmosphere since it can’t radiate away”
This is your imagined singularity which can’t physically happen. The atm. with reduced IR active gases COULD still radiate away thermodynamic internal energy to deep space as all gases radiate. As I wrote, the outgoing LW emission spectrum would shift to bands with appropriate emissivity.
Suppose, for example, the effects reducing the albedo, cancel the effects increasing the albedo. Then the balance would still be ~240in/240out with most of the LW out coming from the surface, the rest from the atm. In this case, the environmental lapse with less humidity would rotate about a point in the mid-troposphere (toward the ideal lapse) reducing the surface temperature at the new equilibrium and increasing the temperature at the tropopause to conserve the same thermodynamic internal energy in the system. Consistent with less cooling due IR active gas in the high atm. regions, less warming in the lower/surface regions.
”convection stops”
No. Especially not buoyant convection. As I wrote, the surface would still be randomly warming the fluid above ambient from below in a gravity field with less IR active gas and convection would ensue thus persist as would the lapse, geostrophic and trade winds et. al. circulation.
”it can’t radiate away…No singularity”
…is a contradiction in terms thus you have not thought this through well enough. Imagining something that can’t radiate creates a divide by zero, a singularity. After which you can imagine anything you wish as you cannot be proven wrong…or right by experiment.
“This is your imagined singularity which can’t physically happen. The atm. with reduced IR active gases COULD still radiate away thermodynamic internal energy to deep space as all gases radiate. As I wrote, the outgoing LW emission spectrum would shift to bands with appropriate emissivity.”
Trick, you were the one who pointed to the article where it said total N2 and O2 emission was 0.28 watts/sqM as against 100+ watts/sqM from GHG’s. The thermal emission spectrum can’t “shift” (although the centroid changes if some bands disappear). Thermal emission depends only on temperature and emissivity and all bands which can emit will be present in the spectrum. So if the current GHG bands disappear all the other emission bands stay the same unless the temperature changes. Other bands can’t suddenly increase to make up the difference. Thus when the GHG bands vanish the emission to space of the tropopause drops by a factor of 400 which would not really be enough to maintain meaningful convection. The only way loss to space could increase would be if the tropopause got a lot warmer which would also mean less (no meaningful) convection.
”it can’t radiate away…No singularity”
…is a contradiction in terms thus you have not thought this through well enough. Imagining something that can’t radiate creates a divide by zero, a singularity.
Why is saying the atmosphere sans GHG cant radiate equivalent to a singularity or dividing by zero. If it can’t radiate it also can’t absorb (emissivity = absorptivity) so radiant heat transfer is no longer possible and the temperature will be determined ultimately by conduction and possibly convection. What is the problem with that and where does the divide by zero come in? Simply means it will equilibrate to the same temperature as its surroundings or in this case the surface. Of course convection is not symmetrical, when the surface is hotter convection will occur so warming the atmosphere but when its colder convection stops so the atmosphere does not cool as much, thus the atmosphere will equilibrate to close to the highest surface temperature which means on average it will be warmer than the surface – a static temperature inversion.
The surface will not warm the air above it because the air above it is already either at the same temperature or possibly warmer (on average) for the reasons described above. Its simply a situation where the surface gains and loses energy by radiation and the atmosphere above is transparent and does not influence the radiation gain/loss from the surface. Convection in the short term and thereafter conduction simply ensures the entire atmosphere reaches the same temperature and remains static.
I come back to the original point – weather is mechanical energy and this is derived from the sun which means the atmosphere is a heat engine. For a heat engine to function it MUST lose energy from a cold junction but without GHG where is the cold junction and how is the heat lost? Remember you pointed to the paper which indicated without GHG the energy loss by radiation to space would be 400 times lower. That’s nowhere near enough to maintain a weather system. Further, if you insist that it is radiation from N2 and O2 , then how do you define a green house gas and how does it differ from N2 and O2? If the tropopause can readily lose energy without GHG why does their presence or absence matter and why would a small change in CO2 make any difference at all. OK I know we both think it doesn’t make any significant difference but, at least in my case, it’s not because I question the entire theory of GHG action in the atmosphere but rather because I am sure the feedback within the climate system is negative (reducing the 1C per doubling of CO2 impact before feedback to negligible levels) not massively positive as claimed by warmists.
”The thermal emission spectrum can’t “shift””
Sure it can. For example, quickly paint the entire earth surface with a highly conducting metallic paint, thereby reducing the emissivity of the surface to just above zero. The atmosphere keeps radiating as before, oblivious to the absence of radiation from the surface (at least initially; as the temperature of the atmosphere drops, its emission rate drops). Of course, if the surface doesn’t emit as much radiation but continues to absorb solar radiation, the surface temperature rises and no equilibrium is possible until the emission spectrum shifts to regions for which the emissivity is not zero.
”Thermal emission depends only on temperature and emissivity”
No, ideal irradiance only depends on temperature and frequency (Planck). Emissivity is at least a function of illumination (S-B). Here you do not get the most basic stuff correct.
”Why is saying the atmosphere sans GHG can’t radiate equivalent to a singularity or dividing by zero”.
Everything radiates, all the time, due to charged particles moving in a magnetic field. Setting radiation to zero as you do results in the nonsense of no motion at all; in the math a singularity because a 0 shows up in the denominator.
”For a heat engine to function it MUST lose energy from a cold junction but without GHG where is the cold junction and how is the heat lost?”
You are circling back, if you have a new question I’ll answer. One more time, space is the sink, sun is the source, radiation is how surface & atm. LW energy transfers out to space. Radiation is never zero for any matter.
Any more questions? FIRST, look through my existing answers. Maybe even consult a text of your choice.
To have an opinion on climate sensitivity that can be relied upon, you first have to demonstrate an understanding of the basic atm. thermodynamics, basic meteorology which you have not done by asking all these questions.
Ok, one more: ”then how do you define a green house gas”
The best definition I have ever seen is from Bohren 2006 p. 81:
“Water vapor is infrared active; nitrogen and oxygen, for the most part, are infrared inactive. Greenhouse gases are produced by resident cats with digestive problems.”
Trick, I find the tone of your last communication somewhat questionable. Just to set the record straight, while I am recently retired I spent 42 years working as a research scientist/engineer for a multinational spectroscopy company. I have around 20 patents as a result of my research activities. Spectroscopy is the branch of science devoted to the interaction between electromagnetic radiation and matter.
Since you are unwilling to accept my comments here is one from Physics.stackexchange.com
Difference in Thermal radiation in condensed matter and gases
[In a solid or liquid the electrons in the valence and conduction bands are roughly uniformly distributed so we have a continuous distribution of electrons throughout the whole material. By contract in a gas we have atoms or molecules widely separated by vacuum where there are no electrons.
The reason this matters is that the radiation mentioned in the quote, black body radiation, is mainly produced by oscillations in the electron density. Thermal motion makes the atoms oscillate and this produces changes in the electron density. This in turn produces oscillating electric dipoles, and those dipoles emit the black body radiation.
In a gas at everyday temperatures and pressures this can’t happen because the gas atoms or molecules are too widely spaced. There is no continuous distribution of electrons to oscillate, and as a result gases do not emit black body radiation. The radiation emitted by gases generally consists of sharp lines related to rotational or vibrational transitions.]
In the case of N2 and O2 there are no resonances corresponding to wavelengths between about 8 microns and 50 microns thus there are no emission lines in that portion of the spectrum. Your second post effectively confirms that by stating N2 and O2 are infrared inactive while water vapour is IR active. Infrared inactive means no emission bands in the thermal IR! Sure N2 and O2 have emission lines in the microwave region but at a temperature of 200K to 300K the emission is extremely weak – too weak to have much significance on the atmospheric heat engine.
You say I am recycling my question as to what is the cold junction and energy loss mechanism. It’s because you did not answer it first time! You seem to be implying in your latest comment that it’s still the tropopause and that since in your words everything above absolute zero emits energy, that’s enough to establish the energy loss mechanism. Yet the paper YOU cited points out that only about 0.28 watts/sqM out of a total of >100 watts/sqM comes from non green house gases. The weather system on earth currently loses >100 watts/sqM from the cold junction. Do you really think that can be reduced to 0.28 watts/sqM and it will make no difference!
You say [No, ideal irradiance only depends on temperature and frequency (Planck). Emissivity is at least a function of illumination (S-B). Here you do not get the most basic stuff correct.]. Planks law gives the thermal emission from a black body at a specific temperature as a function of wavelength. Stefan Boltzmann gives the total emission from a black body at a specific temperature ie: it is the integral of Planks law over all wavelengths. Neither has anything to do with irradiance which is the flux of radiant energy flowing through and normal to a defined area. Thermal emission at a given wavelength does only depend on temperature and emissivity at that wavelength. In some cases emissivity can depend on temperature. For example, if you heat a gas to the point where it dissociates or ionises to an appreciable degree that will fundamentally change the emissivity but that is far outside the scope of what we are discussing in relation to weather.
Your first paragraph is almost meaningless. Highly conductive metals have high emissivity since they have lots of free electrons. The atmosphere keeps radiating -of course; changing the Earth’s surface does not change the emissivity of the atmosphere. Emissivity is a property of the emitting object not a property of the radiation received and we have been taking about the emissivity of the atmosphere. You mention the surface continuing to absorb solar energy while not radiating. This could only happen if the absorptivity/emissivity is high in the visible but low in the IR (unlikely but not impossible). In that case the temperature rises but the emission bands do not shift. What happens is the intensity of each band changes as a result of the rise in temperature according to Plank’s law.
”The radiation emitted by gases generally consists of sharp lines related to rotational or vibrational transitions.”
Ok, something new and interesting here Michael. The particular .com passage ignores a ton of details in the science of spectroscopy. If you worked in the field, then get down off your shelf some books on the subject and quote from those to continue the discussion.
For example, my shelf contains what once was, and perhaps still is, the standard treatise on atomic spectra, by Condon and Shortley, fills 432 pages of text. Herzberg’s treatises fill 581 pages for diatomic molecules, 538 pages for polyatomic molecules, and 670 pages for the electronic spectra of polyatomic molecules. Townes and Schawlow devote 648 pages to microwave spectroscopy.
The physical strain of lifting these nearly 3000 pages is as nothing compared to the mental strain of absorbing them. Add to these the dozens if not hundreds of books on quantum mechanics and modern physics. Spectroscopy is the science of detail and I submit you will not find that passage from Physics.stackexchange.com in any of these works.
Many spectroscopists do plot spectra as a function of wavenumber (inverse wavelength, equivalent to frequency) and would consider doing otherwise an unnatural act. For me, I prefer micron units as around here it’s easier on the keyboard.
The detail missing in your .com passage is because gas molecules are in motion, they are illuminated by radiation of frequency slighted shifted from that of the source, and emit radiation the frequency of which is also shifted based on their speed at emission time. This is usually less than that resulting from inter-molecular forces sometimes called collisional broadening.
Find on you own the emission spectra of gas with an exposure time on fast film (or better ccd) of more than 30 minutes. You will find a continuous gas emission spectrum unlike what you quoted from that .com. And if not, lengthen the exposure time.
”You say I am recycling my question as to what is the cold junction and energy loss mechanism. It’s because you did not answer it first time!”
7:12am: “With reduced IR active gas, the tropopause would still be much cooler than the surface due the lapse rate which would not change (much). There essentially would still be weather.”
”Plan(c)k’s law gives the thermal emission from a black body (cavity) at a specific temperature as a function of wavelength. Stefan Boltzmann gives the total emission from a black body at a specific temperature ie: it is the integral of Plan(c)k’s law over all wavelengths.”
Now you got it right Michael try to stick to that.
”You mention the surface continuing to absorb solar energy while not radiating. This could only happen if…” you leave your shiny seat belt buckle in the sun. I did not mention NOT radiating, I specifically mentioned: “Radiation is never zero for any matter.” So you are not absorbing what I am writing and further discussion is useless unless you have something new and interesting.
How about more meteor impacts? The moon has certainly absorbed a lot of punishment that otherwise would have been inflicted on the Earth. As I recall, the dark side of the moon is a lot more cratered than the side which faces Earth.
If the Earth lost the Moon then all the “Climate Change” and resultant disasters would still be Man’s fault.
For documentary evidence search for “Space: 1999”.
(Al knows this. He invented the series.)
As for moonlight, why can’t we put some artificial moons up there to give us more moonlight. I have no idea if this is remotely possible, but I do love a good moonlight.
How long before a press release announces a paper “showing” that the moon will disappear because of climate change? [Under RCP18.5]
Can’t believe the most significant loss has been overlooked in this comment string. The music! No Dark Side of the Moon? Pink Floyd would have never got better than Ummagumma!! No Caught between the Moon and New York City?! Chris Cross with no movie soundtrack? And (gulp) No Amore (when the moon hits your eye…)? Dean Martin would have been forced to rejoin Jerry Lewis!!! OMG we’d be better off doomed!!!
This is, of course, /sarc. Meddle was WAY better.
Songwriters would have to rhyme June with croon, tune and loon (the bird). Or goon.
The Tragedy of the moon,Isacc Asimov.
Was a damn fine read 30 years ago.
I wonder what would change,given what we have learnt since this was published?
What Would Happen to Earth’s Climate if we had no jurinalists? (Swedish pronunciation)
Venus has low rotation rate. The scientists studying Mars think a major impactor disrupted Mars’ dynamo, modeling says Earth’s dynamo would restart after such an impact.
What would happen to the Earth if we had no climate scientists?
When playing “What if?” all sorts of what ifs come to mind.
What if my granny had wheels?
Can anyone explain to me how this varying axial obliquely of up to 10 degrees comes about? What makes the angular momentum of the planet go unstable? Earth is not a spin top with an overturning moment….
No moon to pull on big mammalian protuberances ?!? Only earth’s pull downwards ? Perish the thought , that sight would just be too much to stomach….
This entire discussion has focused around a form of lunacy!
So they’re saying “Space 1999” was Science Fiction….
https://www.google.com/search?q=no+moon+no+earth&oq=no+moon+no+earth&aqs=chrome.
Moon – Spoon – June
No moon, no werewolves.
Without a / 1 / stabilizing moon for a / 1 / real existing planet
we won’t be there.
plain simple.
https://www.google.com/search?q=moon+locked+rotation&oq=moon+locked&aqs=chrome.
We wouldn’t have plate tectonics and surface refresh resulting in life.
No life.
A lot of absolute nonsense here. If earth had not captured and kept a moon, it would look like Venus.
Slow spin rate
no ocean development
No mechanism to pull gases from atmosphere, yes co2
That will be a fascinating topic. The moon once was very close to the Earth now is far more away from the Earth.