Sceptic agrees global warming real.

This is for the global warming skeptics. June 2013 was the 340th month in a row with the monthly average global temperature was above the 20th century average
global temperature.
http://www.climatecentral.org/news/june-extends-globes-warm-streak-to-340-months-16258
Now then, if there is no warming then the global average temperature is just as likely to be below the average as above the average.
So to show that there is no warming, take a coin and flip it for heads or tails. If you can flip 340 heads in a row you will have made your case.
The probability is 1 in 2^340 or about 1 in 2.24 x 10^102. Absolutely no way.
 
"global warming" may not be the dumbest phrase I ever heard, but it sure comes close. It is a highly inaccurate rhetorical soundbite means of expressing anthropogenically assisted atmospheric forcing which is effecting the earths climate.
Even a cursory glance at paleoclimates that were warmer than today shows that they were (as far as the proxies take us) more equable than today.
While it was 8 degrees warmer and wetter and forested in the arctic(see the lake e'lgygytgyn studies), the temperate zones saw little change, while the tropics dried out some(at-least in brazil)---that's high latitude and high altitude warming, not quite global, and calling it such is like assuming that all women or all blacks or all whites are alike. It is, on a good day, a pathetic estimation of an average.
Unless we are in a super interglacial(lake e again) this interglacial ain't got much more time.

To the best of my knowledge, no one is certain just why it is that we drift into an ice age, or out of one, nor how long this one will last. We ain't even certain how many have preceeded this current one.

If this ice age ain't over, and we ain't in a superinterglacial, the ice should return within a couple thousand years. Add in another massive volcanic eruption and a volcanic winter, and the ice may come on real damned fast, with attendant famine war and disease.
on the other hand:
With with continental ice sheets and lower sea levels, the archaeologists will finally be able to begin to search for early modern human habitations and migrations along the coastlines of 20-40kybp..........................yippee
 
... Even a cursory glance at paleoclimates that were warmer than today ...
Yes, that is true and even the atmospheric CO2 levels have been several times higher than they are today with life surviving. Thus, you and many others conclude that while “global warming” may be inconvenient for some and a blessing for others (lower shipping cost with ice free Arctic Ocean, more useful Siberia, etc.) it is no threat to life on Earth.

What this POV ignores is than the RATE of CO2 release with burning of fossil fuels is hundreds of times faster than ever before in Earth's history. This may convert Earth into a cooler version of Venus with a high pressure steam atmosphere - a completely sterile planet.

There is a thread called “apocalypse soon” (at http://www.sciforums.com/showthread.php?133084-Apocalypse-Soon) in which I have disputed the OP's idea that “peak oil” will make such damage to the economies of he world that > 95% people will die. I argue that man is adaptive and there are already well known technologies for societies to run on solar energy at quite affordable costs. For example as Brazil* now mostly does and the entire world could as I show in post 1436 of that thread. (many pages back now).

But what I want to call your attention to is how the earth may switch to its hot stable state as Venus did some millions of years ago. I. e. a state with IR opaque atmosphere, making the surface temperature of Venus above the melting point of lead. Some of Earth's metals would be melt too if Earth were in its “Hot Stable State”

Methane, CH4, is a GHG at least 10 times more effective at blocking IR radiation from escaping into space than CO2 is. In Earth's past the “global warming” was much slower than now with man's rapid burning of fossil fuels, and thus the release of CH4 stored in methane hydrates was much slower – so slow that the atmospheric destruction of CH4 kept the concentration of CH4 in the air very low. That is not the case now – the CH4 concentration is rising long with that of CO2.

Recently, in the shallower Arctic Ocean where water is warming rapidly, methane hydrates are decomposing, releasing CH4. I.e. kilometer diameter “clouds” of bubbles of CH4 are rising up to the surface and then entering the atmosphere. Fortunately CH4 is destroyed by atmospheric processes with a half life of only slightly more than a decade. Unfortunately, there is more carbon stored in the methane hydrates than ever was stored in all the coal and oil!

There exists the real possibility that we have already activated two positive feed back loops that may make Earth sterile in a few thousand years. I. e. the unprecedented rate of CO2 now making an unprecedented rate of CH4 release from methane hydrates is self accelerating process. If the “loop gain” of these feedback loops is already greater than unity, EARTH WILL SWITCH TO ITS HOT STABLE STATE. If the loop gain is not yet greater than unity it may be possible thru reduction of the RATE of CO2 release to prevent a thermal run away of Earth's surface temperature.

I posted some of these concerns in the above thread as a completely sterile Earth with a high pressure steam atmosphere would be a real catastrophe and “peak oil” is only an inconvenience, requiring more utilization of solar energy. See first post1056, and then 1061 of the above link.

* Less than 5% of Brazil's electrical energy comes from fossil fuels. ~85% is hydro-power, more than 5% is thermal steam made by burning the sugar cane after it has been crushed and supplied the distillation of alcohol heat requirements, wind and solar PV make a few percent each and Brazil's one nuclear site makes about 1%. The sugar cane alcohol not only fuels Brazilian cars but also now Braskem is making 400,000 TONNES of plastic annually from sugar cane, not oil, at lower cost than oil at $90/ brl or greater.
 
it is no threat to life on Earth.

What this POV ignores is than the RATE of CO2 release with burning of fossil fuels is hundreds of times faster than ever before in Earth's history. CO2 release with burning of fossil fuels is hundreds of times faster than ever before in Earth's history
no threat? well
maybe
I find it highly likely that, as the climate shift, some years the wrong crops will be planted in the wrong places, and we'll remember what fasting is like.

as/re:
CO2 release with burning of fossil fuels is hundreds of times faster than ever before in Earth's history

Often claimed, never proven, and the ice cores do offer a slightly different perspective(for this ice age) with sudden co2 spikes.

as/re:
This may convert Earth into a cooler version of Venus with a high pressure steam atmosphere - a completely sterile planet.

That is just about as likely as the earth swapping orbits with mars..........and most likely, a whole lot less likely than that.

Plants feast on co2 and have increased the greening of the temperate zones by 20% as/re nasa, and lowered the percentage of new co2 staying in the atmosphere, as/re Hansen.
Trees are moving poleward. clouds are lowering and likely loosing heat to the stratosphere.(nasa again)
SSWs are cooling the northern mid latitudes.

Speak not too loudly from fear nor ignorance.
Hyperbole may have it's place in rhetoric, politics, and story telling, eschew it's inclusion within the sciences.
 
I keep meaning to drop in here just to ask:

Because this skeptic has finally gotten around to agreeing, does that mean that global warming really is real now?

Done :) Have fun!
 
... What this {"global warming" is not a serious problem as CO2 levels have been much higher in Earth's past"} POV ignores is than the RATE of CO2 release with burning of fossil fuels is hundreds of times faster than ever before in Earth's history. ...
... Often claimed, never proven, and the ice cores do offer a slightly different perspective(for this ice age) with sudden co2 spikes. ...
Yes that too is true. After a large volcanic eruption the ice cores do record much higher rates of CO2 release than now. It can takes even a few decades for that "burp" of CO2 to be removed, by growing plants and absorption into the oceans. What I am concerned about is the STEADY and slightly accelerating CO2 release acting for 100 or more years.

{post 1056 of "catastrophe thread" in part}... A modest rate of CO2 induced CH4 release will not make a greater than unity thermal instability run-a-way thanks to the high atmosphere destruction rate of CH4, but some rate of methane hydrates destruction may send earth into it hot stable state, when one factors in that the increased CH4 concentration also make the even more effective IR blocker (water) concentrations in the atmosphere increase also.

This is a very complex, multi-faceted, dynamic interaction problem* with many important coefficients basically set just by just some “experts” guessing. - I am not saying the switch to the hot, high-pressure, steam atmosphere MUST happen - only telling how it could and AFAIK no one has firmly proven that it will not with CO2 being released faster than 2ppm annually. To be safe, assuming it is not already too late, man needs to cap the CO2 concentration curve below and turn it downward, IMHO.

mauna-loa-C02-ppm-full_record.png.662x0_q100_crop-scale.png
How high must CO2 rapidly climb to make Earth sterile?
Will 430ppm by 2023 do it? If so we do still have a decade to get off the oil teat - to finish with burning oil.

* Many who only consider the fact CO2 has been several times higher in Earth´s past, take comfort in that fact, as they don´t understand it is the unprecedented RATE of CO2 release that is the threat. CH4 must diffuse up to high altitudes to be destroyed by UV. That gives it "atmospheric half life" of at least a decade. Slow CO2 release will not put much CH4 in the atmosphere even with CO2 slowly climbing to 10,000ppm. Without rapidly increasing CO2 inducing growing CH4 concentrations, there is no thermal run-a-way instability. It is the CH4 and then the H2O positive >1 feedback loop gains that can make Earth Sterile.
It is a simple fact that submarines in WWII era could use their sonars everywhere in the shallow Arctic waters but now can not see thru the rising clouds of CH4 bubbles. The atmospheric concentration of CH4 is now rising and was basically static with release rate = destruction rate until about 25 years ago. At what level will Earth be beyond the rescue with rising CO2 & CH4 concentration? I. e. trapped in a greater than unity positive feed back loop with run-a-way surface temperature, until the great heat capacity of the oceans with surface boiling stabilizes the surface temperature at ~105 C for more than a million years?

Can you (or anyone) tell at what level and rate of release of CO2 & CH4 atmospheric concentrations the loop gain exceeds unity?
http://thinkprogress.org/climate/2011/04/25/207958/methane-hydrate-feedback/ said:
Methane Gun hypothesis. It postulates that methane clathrate at shallow depth begins melting and through the feed-back process accelerate atmospheric and oceanic warming, melting even larger and deeper clathrate deposits. The result: A relatively sudden massive venting of methane – the firing of the Methane Gun. Recent discovery by Davy et al (2010) of kilometer-wide (ten 8-11 kilometer and about 1,000 1-kilometer-wide features) eruption craters on the Chatham Rise seafloor off New Zealand adds further ammunition to the Methane Gun hypothesis.

It has been known for many years that methane is being emitted from Siberian swamplands hitherto covered by permafrost, trapping an estimated 1,000 billion tons of methane. Permafrost on land is now seasonally melting and with each season melting it at greater depth, ensuring that each year methane venting from this source increases.

Methane clathrate has accumulated over the East Siberian continental shelf where it is covered by sediment and seawater up to 50 meters deep. An estimated 1,400 billion tons of methane is stored in these deposits. By comparison, total human greenhouse gas emissions (including CO2) since 1750 amount to some 350 billion tons.
 
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Yes that too is true. After a large volcanic eruption the ice cores do record much higher rates of CO2 release than now. It can takes even a few decades for that "burp" of CO2 to be removed, by growing plants and absorption into the oceans. What I am concerned about is the STEADY and slightly accelerating CO2 release acting for 100 or more years.
We have seen far faster rises in CO2 concentrations. We have seen far higher total CO2 concentrations. No "steam death."

It is a simple fact that submarines in WWII era could use their sonars everywhere in the shallow Arctic waters but now can not see thru the rising clouds of CH4 bubbles. The atmospheric concentration of CH4 is now rising and was basically static with release rate = destruction rate until about 25 years ago. At what level will Earth be beyond the rescue with rising CO2 & CH4 concentration?
We have seen far higher CH4 concentrations.

I. e. trapped in a greater than unity positive feed back loop with run-a-way surface temperature, until the great heat capacity of the oceans with surface boiling stabilizes the surface temperature at ~105 C for more than a million years?
Yes, that could happen. You could spontaneously burst into flames as well - and that event is even more likely. Still, no need to buy asbestos underwear.
Can you (or anyone) tell at what level and rate of release of CO2 & CH4 atmospheric concentrations the loop gain exceeds unity?
Some safe bets:

CH4: when it exceeds 500 parts per million, since historically there have been such concentrations without "steam death." (Currently at 700 parts per BILLION.) So you'd have to increase it almost 1000x.
CO2: when it exceeds 3000 parts per million, since historically there have been such concentrations without "steam death." (Currently at 400 parts per million.) So you'd have to increase it about 8x.
 
Some safe bets:

CH4: when it exceeds 500 parts per million, since historically there have been such concentrations without "steam death." (Currently at 700 parts per BILLION.) So you'd have to increase it almost 1000x.
CO2: when it exceeds 3000 parts per million, since historically there have been such concentrations without "steam death." (Currently at 400 parts per million.) So you'd have to increase it about 8x.
Assuming Earth even has sufficient insolation to achieve such a state. I have previously posted a paper for Billy T, which it seems Billy T has disregarded thatsuggests that insolation would have to increase by at least 10% for Billy T's hypothesis to be plausable.

It seems Billy T has chosen to disregard that paper and pursue his hypothesis instead.
 
Assuming Earth even has sufficient insolation to achieve such a state.

Agreed. It would have been more accurate to say that such a state will not occur when CH4 is below 500 parts per million and CO2 is below 3000 parts per million. Above that it is still unlikely.
 
Playing devil's advocate here (my hunch is that if the clathrate gun were set to that delicate a trigger it would have fired already, or more likely never have loaded itself), we note that in the past times of high methane and CO2 concentration both the sun was considerably dimmer, and putting out somewhat different wavelengths.

Also, the heat distribution and cloud cover patterns were quite a bit different.

That is, the assumption that if we have survived high methane and CO2 concentrations before without boiling out we surely will again, is not quite safe.
 
... I have previously posted a paper for Billy T, which it seems Billy T has disregarded thatsuggests that insolation would have to increase by at least 10% for Billy T's hypothesis to be plausable. It seems Billy T has chosen to disregard that paper and pursue his hypothesis instead.
No, I did not “disregard” paper you linked to with this post: 1162 of the Apocalypse soon thread:
This paper may be of some interest to the discussion regarding whether or not it's possible to turn Earth into Venus at this time.
Runaway and Moist Greenhouse Atmospheres and the Evolution of Earth and Venus; Kasting, J. F, 1987

As I recall it comes to the conclusion that solar insolation is insufficient at the Earths orbit to drive Earths climate to that extreme.
I did NOT “disregard” the paper. I carefully read it and then I pointed out that the paper made two very questionable assumptions that FORCED their conclusion.

The first assumption is totally false - impossible. It assumes a thick band (40% of the atmosphere they consider) next to the surface is at a fixed temperature of 200K. (100K LESS than the current surface temperature!) They even admit that without this assumption, their solution “blows up” - temperature increases without limit! Their second assumption also is nearly impossible. With either of these false assumptions, yes their model shows there is no run-a-way temperature problem.

Here is my earlier posted comments on their paper:
{post 1163, in part} … They assume in Fig 1 that the atmospheric temperature is a constant (because of large convection and radiative transfer) at 200K, yes K, for about 40% of the altitude range they consider! Then increases with temperature adibatically to about 1400K at the highest altitude they graph (They give no T scale but the peak T is ~7 times higher than the graphed and labeled 200K part. It is reasonable that above some minimum T the temperature rises, as happens now in the atmosphere.

When density is low the radiation from it is low and even just scattering or solar photons heats via the recoil, and they do still absorb. What seems impossible to me is a thick band of 200K atmosphere between ~300K surface and a many times deeper band of thinning air with T rising from 200K to about 1400K.

They say at bottom of page 475 this assumed deep constant T = 200K was "motivated primarily by expediency" (lower computational cost in ~1986 they also admit later) and that another earlier model that did try to do a radiative/convective analysis "failed to converge at high surface temperatures" – I. e. it blew up. - Sure seems like the baby got tossed out with the wash water to me.

The other very self-fulling assumption is in Fig 2. Radiative flux, up and down separately, as function of pressure (which is dropping with altitude, of course) ASSUMING AT THE SURFACE IT IS FIXED AT 2 bar! (about twice our 14.7psi). Of course if that is your assumption surface pressure as ocean evaporate the pressure will not go to >10,000 psi as I expect it too. (Nor by their figure 1 assumption, will the surface temperature even get as hot as it is now!)

But thanks anyway. You are not at fault for me spending more than an hour carefully reading first part before discovering (I think) they threw two babies out with the wash water when it came time to calculate at an affordable cost.
In post1171 you did try to defend these improbable or false assumptions that force the conclusion they reached.

I was not persuaded of their merit but did not reply to your post 1171. I will let the reader review post 1171 and seen if these indefensible assumptions that force the conclusion are reasonable. I think your arguments about Venus are irrelevant as I am not suggesting the same mechanism that caused Venus to switch to it hot stable state is operating on earth. Man's unprecedented rapid release of CO2 from fossil fuels, not plate tectonics or lack there of is the potential threat to life on Earth.

Again let me stress, I am not predicting that Earth will switch to its hot stable state with a high pressue steam atmosphere – only expressing concern that it could via very well accepted physical mechanisms if man releases CO2 at and every increasing rate as he is now doing. At what level and rate of CO2 release the positive feed back loops the CO2, CH4 & H2O green house gas concentrations must reach for greater than unity gain and thus a run-a-way thermal instability is unknown but such a level and rate combinations certainly does exist.
 
Japan is already getting CH4 from methane hydrate on the floor of the S. China Sea. The CH4 of the hydrates will be used for fuel and that, with continued burning of oil, may release CO2 even more rapidly than now, freeing CH4 now safely stored in the hydrates faster than it can work its way up to the high atmosphere where UV can help the CH4 over the energy threshold to be destroyed by oxidation, in a greater than unity gain run-a-way thermal instability that pauses at ~100C while the oceans boil away.
Burning CH4 releases a lot less CO2 compared with burning oil.

Also, the world population is proposed to peak and begin a gradual decline beginning in 35 years, if so, the stress on the planets eco systems combined with technology may lead to a an ecological resurgence.
 
Playing devil's advocate here (my hunch is that if the clathrate gun were set to that delicate a trigger it would have fired already, or more likely never have loaded itself) ...
It is certainly "loaded" See reference in 3d quote of my prior post 128 that states there is four times more tons of methane hydrate on just the East Siberian continental shelf than all the 350 million tons of green house gases man has released. It also stats the there are 1000 tones in the frozen Siberian tundra and it is being released now at an ever increasing rate.That same link note the methane hydrates are now decomposing, not only in the rapidly warming arctic waters but also from the Chatham Rise seafloor off New Zealand. Currently only the relative shallow ocean bed methane hydrates are decomposing as greater pressure tends to stabilize them. SUMMARY: The clathrate gun is not only "loaded", its fuse is burning.

It may have fired weakly at least twice before. Many believe it was responsible for the two larges mass extinction of life on Earth but those earlier "explosions" of CH4 release were mild compare to the one that appears to be coming. Back then the rates of initiating CO2 release were much lower than now - man is now burning a century of stored solar energy (oil, coal and natural gas) every day!

The Big Burp: A Bad Day in the Paleocene - NOAA Ocean Explorer said:
In 1995, Australian paleoceanographer Gerald Dickens suggested that a sudden release of methane from submarine sediments during the Paleocene epoch (at the end of the Tertiary Period, about 55 million years ago) caused a greenhouse effect that raised the temperatures in the deep ocean by about 6° C. The result was the extinction of many deep-sea organisms known as the Paleocene extinction event. More recently, other scientists have suggested that similar events could have contributed to mass extinctions during the Jurassic period (183 million years ago), as well as to the sudden appearance of many new animal phyla during the Cambrian period (the “Cambrian explosion, about 520 million years ago).
A key objective of the 2003 Windows to the Deep Ocean Exploration expedition is to investigate the possible release of methane from methane hydrates to the atmosphere and the potential impact of these releases on global warming. This activity focuses on methane hydrates, global warming, and the Paleocene extinction event.
Note this is NOAA article title, not a "click on" link. To read article, google search this title.
 
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Burning CH4 releases a lot less CO2 compared with burning oil. ...
Yes replacing BTUs of oil with methane is a help, but that is not what Japan is doing. They are replacing nuclear energy with more fossil fuel burning. I also think they will disturb the safely stored deep methane clathrates with their extraction and release tons of methane unburned.
 
Agreed. It would have been more accurate to say that such a state will not occur when CH4 is below 500 parts per million and CO2 is below 3000 parts per million. Above that it is still unlikely.
Where did you get these values? You seem to not be aware that even increasing the current 400ppm of CO2 to 1000ppm, much less 3000ppm would not produce much global warming as CO2 can only block the escape of IR in its absorption bands and is already at current concentrations blocking about 2/3 of that part of the IR "earthshine." CH4, in contrast has wider bands and is far from fully blocking the IR it could.

CO2 is a linear molecule: OCO and CH4 is a "3D" molecule so has more and wider and more complex rotational and vibrational bands for IR absorption, but neither is polar. H2O is a polar molecule (both the H are on the same side of the O with a 105 degrees angular separation spread. Thus, the H side is permanently positive and the O is permanently negative.) H2O is a much stronger IR absorber than even CH4 which is more than 10 times as effective as CO2, molecule per molecule basis even if CO2 were not already nearly saturated with little possibility of absorbing more. This is a very complex, inter acting set of molecular absorbers making global warming.

Simple numbers like your give are essentially meaningless. A 10%, just guessing, increase in the water vapor concentration would increase global warmingmuch more than a 1000 fold increase in CO2 concentrations would! Probably the most important increases in global warming are being caused, in a positive feed back way, by slight increases in the average amount of water vapor the warmer air can hold prior to raining some out. As I said it is a very complex problem and I doubt anyone really understands it or even has all the interaction cross section and altitude / UV effects coefficients (especially those related to the chemical destruction of CH4) correct.

Do you want to bet the existence of life on earth that they do? Or would it be wise to switch away from burning fossil fuels ASAP (like Brazil has basically done. Read how world could at post 1436 of the apocalypse thread.)?
 
No, I did not “disregard” paper you linked to with this post: 1162 of the Apocalypse soon thread:I did NOT “disregard” the paper. I carefully read it and then I pointed out that the paper made two very questionable assumptions that FORCED their conclusion.
Yes you did. You disregarded it on the grounds that you felt ts assumptions were fatally flawed. The fact that you have disregarded it is self evident in this thread.

The first assumption is totally false - impossible. It assumes a thick band (40% of the atmosphere they consider) next to the surface is at a fixed temperature of 200K. (100K LESS than the current surface temperature!) They even admit that without this assumption, their solution “blows up” - temperature increases without limit! Their second assumption also is nearly impossible. With either of these false assumptions, yes their model shows there is no run-a-way temperature problem.

Here is my earlier posted comments on their paper:In post1171 you did try to defend these improbable or false assumptions that force the conclusion they reached.

I was not persuaded of their merit but did not reply to your post 1171.
And as I pointed out to you in my reply:
Yes your memory is correct. I read very carefully several pages to the Fig. 1 point, where it seems two assumptions assumptions forces that conclusion:

Paper is a .PDF so I don´t know how to copy their figures 1 & 2, where quite questional assumptions are made (The first seems nearly impossible to me).

They assume in Fig 1 that the atmospheric temperature is a constant (because of large convection and radiative transfer) at 200K, yes K, for about 40% of the altitude range thay consider! Then increases with temperture adibatically to about 1400K at the highest altitude they graph (They give no T scale but the peak T is ~7 times higher than the graphed and labled 200K part. It is reasonable that above some mimium T the temperature rises, as happens now in the atmosphere. When density is low the radiation from it is low and even just scatering or solar photons heats via the recoil, and they do still absorb. What seems impossible to me is a thick band of 200K atmosphere between ~300K surface and a many time deeper band of thinning air with T rising from 200K to about 1400K.

They say at bottom of page 475 this assumed deep constant T = 200K was "motivated primarily by expediency" (lower computational cost in ~1986 they also admit later) and that another earlier model that did try to do a radiative/convective annalysis "failed to converge at high surface temperatures" - I.e. it blew up. - Sure seems like the baby got tossed out with the wash water to me.
Either I've misunderstood you, or you've misunderstood the paper.
They assume the stratosphere is isothermal at 200k and the troposphere behaves convectively following adiabats.
If you look at figure 3, you'll see they justify this by pointing out that the tropospheric contribution to outgoing flux remains virtually unchange ujp to 250k.

Consider this source Atmosphere of venus on wiki which suggests the tropospher extends to a height of 65km and has a temperature at its top of around 240K. Seems like a reasonable assumption supported by emperical edvidence to me.

The other very self-fulling assumption is in Fig 2. Radiative flux, up and down separately, as funtion of pressure (which is dropping with altitude, of course) ASSUMING AT THE SURFACE IT IS FIXED AT 2 bar! (about twice our 14.7psi). Of course if that is your assumption surface pressure as ocean evaporate the pressure will not go to >10,000 psi as I expect it too. (Nor by their figure 1 assumption, will the surface temperature even get as hot as it is now!)
I think you need to re-examine the explanatory text associated with figure 2. It's illustrating the radiative fluxes associated with a specific example (373K surface temp, 2 Bar surface pressure, 1 bar of which is water vapour). They're using it to illustrate how effective water is at absorbing in the infra red range versus the optical. They're using it to illustrate that 90% of the ir emission comes from the top 10% of the atmosphere, to illustrate how effective water is at absorbing IR.

If you had read on, you would have seen that they examine pressures up to 270 bar. This is three times higher than we see on venus, and the result of evaporating earths inventory of oceanic water.

Your first objection is invalid - they modeled the Earths atmosphere behaving in the same way we observe Venus' atmosphere to behave today.
Your second objection was based on a faulty interpretation of Diagram 3. Diagram 3 is simply illustrating ONE of the scenarios they modeled. They modled a range of surface pressures up to 270 bar which is more than the current surface pressure of venus and what they expected if earths entire inventory of ocean water was evaporated.

You never addressed either of these rebuttals.
You did not explain why Earths stratospher should not be treated isothermally.
You did not explain why Earths sratosphere should have a temperature higher than that of Venus' stratosphere.
You did not explain why you expect Earths atmospheric pressure to exceed a value in excess of that observed on venus and based on the complete evaporation of earths inventory of ocean water.

Perhaps you'd care to address these points now before you peddle your agenda further?

I will let the reader review post 1171 and seen if these indefensible assumptions that force the conclusion are reasonable.
How magnaminous of you. Letting readers wade through around 700 posts to find the one post you're referring to.

Luckily for them I quoted my reply in full.


I think your arguments about Venus are irrelevant as I am not suggesting the same mechanism that caused Venus to switch to it hot stable state is operating on earth. Man's unprecedented rapid release of CO2 from fossil fuels, not plate tectonics or lack there of is the potential threat to life on Earth.

Again let me stress, I am not predicting that Earth will switch to its hot stable state with a high pressue steam atmosphere – only expressing concern that it could via very well accepted physical mechanisms if man releases CO2 at and every increasing rate as he is now doing. At what level and rate of CO2 release the positive feed back loops the CO2, CH4 & H2O green house gas concentrations must reach for greater than unity gain and thus a run-a-way thermal instability is unknown but such a level and rate combinations certainly does exist.

First off, nothing I have p?resented is Venus based.
Second off, the modelling presented in the paper was based around, as I recall, the combustion of Earths entire carbon reserve, and the evaporation of the entire oceanic water inventory of the earth, an they still came to the concluion that it required higher insolation than the earth currently receives.
 
Where did you get these values?

They are historic maximums of both gases.

You seem to not be aware that even increasing the current 400ppm of CO2 to 1000ppm, much less 3000ppm would not produce much global warming as CO2 can only block the escape of IR

I am quite aware of that, which is one reason I find your "steam death" scenario amusing.

CH4, in contrast has wider bands and is far from fully blocking the IR it could.
Correct. And even when its concentration was almost 1000 times higher it did not cause "steam death."

Question - how much higher do you think we can push CH4 concentrations with our best efforts? 1 part per million? 2? 10? You would really have to come up with some bizarre and extradordinary mechanisms to claim a 10 part per million end concentration (over 10 times what we have now) - and even that is 50 times less than the highest historic concentration.

Simple numbers like your give are essentially meaningless.
And wild guesses such as yours are even more meaningless.

A 10%, just guessing, increase in the water vapor concentration would increase global warming more than a 1000 fold increase in CO2 concentrations would!
Really? A cloud covered planet would absorb more total energy? Can you think of any reason that might be an erroneous assumption?
 
... You did not explain why Earths stratospher should not be treated isothermally ...
We must agree to dis agree, but I will respond to this part of your post.

The authors themselves admit (Bottom of page 475.) and now red text in my post 133: (1) they made that constant 200K temperature thick layer next to Earth surface assumption to make the calculation affordable with the computers they had back when it was done (before 1986) AND
(2) They note that the prior calculation efforts which did try to work thru the radiative / convective structure of the lower atmosphere blew up - had unlimited temperature increase.

It is also suggestive of error that no one seems to be quoting them that I can find. Perhaps that is just my lack so searching skills. Do you know of any recent published papers that cite them with approval?
 
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