Man Made Climate Change - Evidence Based Discussion

[Geoffwood]

knocker,

"Another way of putting the first bit is that the earth receives 340w of solar energy for each square meter of it's spherical surface, For a stable climate on earth the planet must radiate the same amount of energy back into space. However that would leave an average surface temperature of -18C."

You have just completely disregarded the Earth's atmosphere. Go look at Trenburth's energy budget.

[Geoffwood]

stewfox, thanks for the feedback. That option to quote does not appear on all links. Not a big blogger, but set in my ways, sorry. Hope common grammar can be translated if more slowly.

[knocker]

By the way it is Dr, K. E. Trenberth. 

knocker,

"Another way of putting the first bit is that the earth receives 340w of solar energy for each square meter of it's spherical surface, For a stable climate on earth the planet must radiate the same amount of energy back into space. However that would leave an average surface temperature of -18C."

You have just completely disregarded the Earth's atmosphere. Go look at Trenburth's energy budget.

 

That was the point.

[Geoffwood]

Interitus, you know this is going to be slow and painful, you say,

"Incidentally stratification means that convective processes from the surface are confined to the troposphere."

I'm afraid this is 'another' physics lesson. Convection is the sum of advection and diffusion. By climate science's admission chemicals from the troposphere are regularly convected into the stratosphere otherwise they wouldn't be able to deplete ozone. The full atmosphere is stratospherically processed within 3 years. We learned that from the isotopes from the first nuclear tests.

[Geoffwood]

Interitus.

"It should be obvious to all that radiative heat transfer from the surface can be VERY effective"

So go and freeze some water when the air temperature is two above. It's simple. Select a fully insulated thermal container with high sides. Make sure no wind disturbs your experiment during the clear night. Otherwise it won't freeze.

[Geoffwood]

Interitus. You say,

" Yes, the troposphere is warming up, at least you got that bit right."

Unfortunately UAH MSU and RSS MSU disagree with you.

[Geoffwood]

knocker, you say,

"knocker, you say,

" Another way of putting the first bit is that the earth receives 340w of solar energy for each square meter of it's spherical surface, For a stable climate on earth the planet must radiate the same amount of energy back into space. However that would leave an average surface temperature of -18C.

The earth emits almost as a perfect black body (slight adjustment of Stefan's Law) There are several gases in the atmosphere that absorb and emit infra red radiation. Thus they allow incoming solar radiation but they trap radiation from the surface. Result reduced radiation back into space and an imbalance. So, quick adjustment and voila we have an average temp of 15C. The easiest way of seeing this is to look at a diagram of spectral distribution of solar and terrestrial radiation plotted logarithmically, together with the main absorption bands. So the atmosphere is partially 'thick'."

 

[knocker]

Knocker,

Is that all you've got?

 

Not quite. I'll include the diagram that I mentioned above to make it easier to understand. It's good to see your education is coming on apace. I think we are reaching the crossroads again.

 

I think you'll agree that looking at the diagram it's amusingly obvious.

 

Spectral distribution of solar and terrestrial radiation, plotted logarithmically, together with the main atmospheric absorption bands. The crosshatched areas in the infrared spectrum indicate the 'atmospheric windows' where radiation escapes to space. The blackbody radiation at 6,000 K is that proportion of the flux which would be incident on the top of the atmosphere. The inset shows the same curves for incoming and outgoing radiation with the wavelength plotted arithmetically on an arbitrary vertical scale.

Edited September 27, 2014 by knocker

[Paul]

Since when did disagreeing with someone's point of view mean you have to be aggressive (verging on abusive at times), condescending and totally disrespectful of that person? Can we all show some humility please, before this turns in a 'my brain's bigger than your brain' type thing rather than a reasoned, potentially interesting debate...

[Interitus]

Interitus, you say,

"Interesting stuff, but at the risk of sounding a bit thick, like with your example of 'if the earth was like the moon, it would be the same temperature as the moon', your theoretical example of parallel high emissivity plates in a vacuum doesn't represent reality that there is an atmosphere."

Yes there is an atmosphere and the 'devil is in the detail'.

The accepted temperature of the Earth, from which the 'greenhouse effect' raises the temperature, is 255K or -18degC and is a 'black body' temperature. The calculation is exactly the same as the 'moon's' temperature, except the calculation for the moon is more accurate. 273K includes a real world estimation of the moon's emissivity and it describes the surface. I'll show you the details if you require.

255K or -18degC for the Earth assumes the Earth has no atmosphere (taken for granted that it represents the surface) and that the Earth emits as a perfect 'black body' when 83% comes from the atmosphere! For an atmosphere to be like a 'black body' it has to be optically 'thick', which the transmission window proves it isn't.

You are accepting the analogy whether you like it or not.

The moon comparison is to show that the total effect of having an atmosphere upon the Earth's surface is actually 15K not 33K

The calculation for 33K enhancement uses the raised albedo of having an atmosphere then neglects the FACTS that the average emission height is not the surface and that the average emissivity of the bodies that answer to space is not that of a black body. Again, I'll show the calculation if you require. ie it neglects the fact that the Earth has an atmosphere!!!!!

Thank you for allowing me to enlighten you. (Again).

 

There is a standard accepted way of calculating equilibrium or effective temperature and that is to include the albedo before considering any atmospheric effects - and this albedo includes atmospheric clouds because they reduce the incoming radiation to the surface without any other effect on the system. The higher the albedo the cooler the planet surface without any insulating greenhouse effect (in the broader sense of the term) because more sunlight is reflected and less available to warm the surface or atmosphere.

Forget obfuscation with physics, it is so very, very simple and this is the universal way it is calculated.

Edited September 27, 2014 by Paul
Removed un-needed comment

[Interitus]

Interitus, you know this is going to be slow and painful, you say,

"Incidentally stratification means that convective processes from the surface are confined to the troposphere."

I'm afraid this is 'another' physics lesson. Convection is the sum of advection and diffusion. By climate science's admission chemicals from the troposphere are regularly convected into the stratosphere otherwise they wouldn't be able to deplete ozone. The full atmosphere is stratospherically processed within 3 years. We learned that from the isotopes from the first nuclear tests.

 

Good. Now back in the real world and the context of energy balance which this was meant, seeing as it was the topic at hand, how much heat is convected from the earth's surface and through the stratosphere?

[Interitus]

Interitus.

"It should be obvious to all that radiative heat transfer from the surface can be VERY effective"

So go and freeze some water when the air temperature is two above. It's simple. Select a fully insulated thermal container with high sides. Make sure no wind disturbs your experiment during the clear night. Otherwise it won't freeze.

 

It's OK, we've got a freezer for our ice cubes. What on earth has that got to do with anything?

[BornFromTheVoid]

 

Interitus. You say,

" Yes, the troposphere is warming up, at least you got that bit right."

Unfortunately UAH MSU and RSS MSU disagree with you.

 

Are you sure they disagree?

 

http://www.skepticalscience.com/satellite-measurements-warming-troposphere-advanced.htm

[stewfox]

 

Are you sure they disagree?

 

http://www.skepticalscience.com/satellite-measurements-warming-troposphere-advanced.htm

 

 

The article looks at trying to find reasons not to agree ?

 

Its a long article but two points I take from it.

 

Differences between various analyses are largely due to analysis techniques and compensations for satellite data issues.

 

Interesting comment within a long review, 

 

 

A telling statement concludes at the end "this error is most likely due to data errors", referring to discrepancies between satellite measurements and model predictions in the tropics. There are at least 3 errors and/or bias evident in this statement. 

1) it is not an 'error', it is a difference between a model and a prediction, to say it is an error is to assume the data is wrong, not the model. The statements preceeding it say no such thing, they say the issue is still open, NOT that there is an error.You have pre-assumed a conclusion, and it is therefore a distorted statement.

2)The statements previous to this do not say 'it is most likely due to data errors', you yourself have concluded and enhanced this, from the previous paragraphs, and you are also asserting it is what John Christy etc says-he simply says 'the issue is still open', and doesnt mention anything about 'likelihood'-you have added this yourself. This is what is known as cooking and re-cooking, to get a desired result. If the same was done to the data, it would be invalid. 

3) And also, you have repeated the word 'error' twice in this sentence, just to re-cook it, again. You have preassumed a conclusion, and cooked the statement twice. Stalin would not have been impressed, and would have advised that one cooking would have sufficed, or the GULAG.

[stewfox]

World on track for worst-case warming scenario

http://www.newscientist.com/article/dn26243-world-on-track-for-worstcase-warming-scenario.html#.VCWzFFez1X6

 

 

Long time since I've seen 5.4c rise by 2100 use to be more common to see that a few years ago ago. The best I saw was 10c but usually 6c/7c.

 

Will be interesting if we see 6-8c creeping back . Worse case stuff.

 

Are we going to see more alarmist reports going back into main stream media ? Which lets face it does nothing for science. The Telegraph 2009

 

Global warming of 7C 'could kill billions this century'

 

http://www.telegraph.co.uk/earth/earthnews/5357725/Global-warming-of-7C-could-kill-billions-this-century.html

Edited September 27, 2014 by stewfox

[Devonian]

3) And also, you have repeated the word 'error' twice in this sentence, just to re-cook it, again. You have preassumed a conclusion, and cooked the statement twice. Stalin would not have been impressed, and would have advised that one cooking would have sufficed, or the GULAG.

 

Stalin? Gulags? In a debate about radiation physics?

[BornFromTheVoid]

The article looks at trying to find reasons not to agree ?

 

Its a long article but two points I take from it.

 

Differences between various analyses are largely due to analysis techniques and compensations for satellite data issues.

 

Interesting comment within a long review, 

 

 

A telling statement concludes at the end "this error is most likely due to data errors", referring to discrepancies between satellite measurements and model predictions in the tropics. There are at least 3 errors and/or bias evident in this statement. 

1) it is not an 'error', it is a difference between a model and a prediction, to say it is an error is to assume the data is wrong, not the model. The statements preceeding it say no such thing, they say the issue is still open, NOT that there is an error.You have pre-assumed a conclusion, and it is therefore a distorted statement.

2)The statements previous to this do not say 'it is most likely due to data errors', you yourself have concluded and enhanced this, from the previous paragraphs, and you are also asserting it is what John Christy etc says-he simply says 'the issue is still open', and doesnt mention anything about 'likelihood'-you have added this yourself. This is what is known as cooking and re-cooking, to get a desired result. If the same was done to the data, it would be invalid. 

3) And also, you have repeated the word 'error' twice in this sentence, just to re-cook it, again. You have preassumed a conclusion, and cooked the statement twice. Stalin would not have been impressed, and would have advised that one cooking would have sufficed, or the GULAG.

 

The guy is basically saying that we don't need to correct for anything, not diurnal drift, orbital decay, ageing instruments, changing instruments, etc, and that all corrections are just attempts to cook the books.

Surely you don't agree with that?

[stewfox]

The guy is basically saying that we don't need to correct for anything, not diurnal drift, orbital decay, ageing instruments, changing instruments, etc, and that all corrections are just attempts to cook the books.

Surely you don't agree with that?

 

I would prefer as John  Christy has said the issue is still open, rather then spin/change the data

 

 

A great read

 

"""Dr. John Christy: Our ignorance of the climate system is still enormous; use of climate models in policy decisions is not recommended""

 

""The bottom line is that, while I have some ideas based on some evidence, I don’t know why models are so aggressive at warming the atmosphere over the last 34 years relative to the real world"". 

 

http://hockeyschtick.blogspot.co.uk/2014/05/dr-john-christy-our-ignorance-of.html

Edited September 27, 2014 by stewfox

[stewfox]

Stalin? Gulags? In a debate about radiation physics?

 

It was being used as an 'analogy'

 

 

http://www.oxforddictionaries.com/definition/english/analogy

Edited September 27, 2014 by stewfox

[BornFromTheVoid]

I would prefer as John  Christy has said the issue is still open, rather then spin/change the data

 

 

A great read

 

"""Dr. John Christy: Our ignorance of the climate system is still enormous; use of climate models in policy decisions is not recommended""

 

http://hockeyschtick.blogspot.co.uk/2014/05/dr-john-christy-our-ignorance-of.html

 

What if the adjustments are clearly justified, needed and make the data more accurate? Calling it "spin", rather than describing why the particular updates/adjustments are unnecessary, seems like a rather lazy form of dismissal. Christy and Spencer themselves have been involved in some of the data updates and corrections.

 

Christy is a knowledgeable guy, but the tropospheric hotspot is not the defining aspect of CO2 induced warming, the cooling stratosphere is.

[stewfox]

What if the adjustments are clearly justified, needed and make the data more accurate? Calling it "spin", rather than describing why the particular updates/adjustments are unnecessary, seems like a rather lazy form of dismissal. Christy and Spencer themselves have been involved in some of the data updates and corrections.

 

Christy is a knowledgeable guy, but the tropospheric hotspot is not the defining aspect of CO2 induced warming, the cooling stratosphere is.

 

The spin is words added like 'likely hood' when the like of Christy never said that you will at least agree with that ?

 

As I have said before whether data 'adjustment' is justified or not there is always a impression its always upwards. I don't have empirical evidence for that so I maybe wrong any links to downward adjustment would be welcome

 

The capacity of the oceans to absorbed this extra heat of course interesting and its early stages but "" Could the extra joules be absorbed by the deep ocean and prevented from warming the atmosphere (Guemas et al. 2013)? This requires extremely accurate measurements of the deep ocean (better than 0.01 °C precision) which are not now available comprehensively in space and time. Current studies based only on observations suggest this enhanced sequestration of heat is not happening""

 

The bottom line is the 'model predictions' are not reflecting real world.

 

Until we seem long term empirical evidence the 'debate' will go on.

[BornFromTheVoid]

The spin is words added like 'likely hood' when the like of Christy never said that you will at least agree with that ?

 

As I have said before whether data 'adjustment' is justified or not there is always a impression its always upwards. I don't have empirical evidence for that so I maybe wrong any links to downward adjustment would be welcome

 

The capacity of the oceans to absorbed this extra heat of course interesting and its early stages but "" Could the extra joules be absorbed by the deep ocean and prevented from warming the atmosphere (Guemas et al. 2013)? This requires extremely accurate measurements of the deep ocean (better than 0.01 °C precision) which are not now available comprehensively in space and time. Current studies based only on observations suggest this enhanced sequestration of heat is not happening""

 

The bottom line is the 'model predictions' are not reflecting real world.

 

Until we seem long term empirical evidence the 'debate' will go on.

 

I don't see expressions of uncertainty as spin, in fact, I'd see it as the opposite. Or maybe I'm misunderstanding your first sentence?

 

The adjustments have gone in both directions, but overall, they've lowered past readings relative to newer. I'll try find some more specific data and post it up during the day.

 

Many studies do suggest an enhancement of ocean heat sequestration, contrary to what Christy says.

Several studies have also shown that model projections are doing a very good job simulating the real world. 

 

Suppose perspective is key!

[Geoffwood]

Hi knocker.

Your attached thumbnail shows that solar radiation is more intense than that of the Earth. The Earth emitting less though from more places.

The two fluxes are not directly comparable. The flux from the sun is near parallel, whereas the Earth's surface emits through 2pi steradians.

The solar flux can therefore continuously exploit the short atmospheric paths continually shown to the Sun as the Earth rotates. Some 80% of the energy entering the Earth system does so within 40deg latitude of the seasonal equator.

However, for all points on the surface many solid angles of emission encounter long atmospheric paths and therefore greater optical 'thickness' and attenuation. Only a those solid angles around the zenith can exploit short paths. This effect is independent of atmospheric composition and is a function of geometry.

Atmospheric opacity can be quantified for incoming radiation from Trenberth's (that ok?) energy balance. The atmospheric opacity for incoming radiation is 0.46 or 46% leaving 0.54 transmitted to the surface.

Of the netted, or real energy that we can express in Wm-2 as part of the surface energy budget, again from Trenberth's energy diagram 63Wm-2 leaves the surface and 40Wm-2 passes through the atmospheric window. Showing a long wave transmittance for the atmosphere of 0.63. So according to Trenberth's diagram the atmosphere attenuates a greater portion of incoming radiation compared to outgoing radiation.

This diagram may help.

The Sun emits at around 0.6um with over 50% of the band radiance at longer wavelengths than 0.7um (IR and beyond). The Earth's peak emission is centred around 10um for 300K.

Edited September 27, 2014 by Geoffwood

[Geoffwood]

Interitus. You say,

"Forget obfuscation with physics, it is so very, very simple and this is the universal way it is calculated."

But it doesn't represent the surface!

The effective black body temperature describes as a single number how the system effectively behaves. The Earth's effective black body temperature is 255K. It in no way means that this is or should be associated directly with the surface. The main component of the Earth system that answers to space is the atmosphere producing 83% of Earth's emissions. As an average in quantity and spatial expanse it describes a mean height above the surface from which the effective assembly of radiators appears. We find 255K in the mid troposphere at a mean altitude of ~5km.

An 'average' in intensity and space makes no assertions about the maximum number in the averaged range nor the extreme of its extent. The surface being the highest temperature at the lowest extent of the radiating range. It represents an average in both.

[Geoffwood]

Interitus, you say,

"Incidentally stratification means that convective processes from the surface are confined to the troposphere."

I feel that I have ready answered this as advection largely stops at the tropopause but diffusion rates don't. The full atmosphere is processed by passing though the tropopause in several years. With respect to energy balance, the stability of the tropopause in terms of meteorological thickness, temperature and altitude reflect its energy balance. If that is not the question you require to be answered please be more specific.