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Radical New Hypothesis on the Effect of Greenhouse Gases

CLIMATE is complex but in an attempt to understand the effects of increasing levels of atmospheric carbon dioxide on global temperatures simplified General Circulation Models (GCMs) have been developed and are used by the United Nation’s Intergovernmental Panel on Climate Change (IPCC).      Al Gore, in his famous movie ‘An Inconvenient Truth’, explained that as the concentration of carbon dioxide increases in the atmosphere, more energy is trapped, warming the planet.   This assumption is central to the GCMs and the current consensus on climate change. 

Some sceptics complain that the GCMs do not realistically simulate climate because there are many processes that can’t be adequately modelled including cloud formation.  Michael Hammer, an engineer who specializes in spectroscopy, is also sceptical of the GCM but his criticism is more fundamental.  In the following paper, using the basic laws of spectroscopy, he shows that a significant portion of energy loss from the Earth’s surface is by direction radiation to space at wavelengths not absorbed by carbon dioxide and other greenhouse gases.    This is in direct contrast to the IPCC explanation that there is low radiation from the Earth’s surface to space and potentially high radiation from the atmosphere to space.

Science is a process of getting it wrong and hopefully learning – on this single issue Michael Hammer and the IPCC can’t both be right.  

AN ANALYSIS OF THE EFFECT OF GREENHOUSE GASES IN THE ATMOSPHERE
By Michael Hammer

1. SUMMARY

Kiehl and Trenberth in 1997 published a global mean energy budget for Earth.  This budget has significant implications for the proposed greenhouse mechanism and indirectly leads to the concept of an equivalent radiation altitude for Earth which changes with greenhouse gas concentrations.  The K&T and similar models form a basis for the global circulation models used in climate science.

This analysis derives a partial global energy budget based on an analysis of the observed atmospheric lapse rate, and basic laws of spectroscopy, which is at considerable variance with the K&T findings.  The differences have significant implications for the greenhouse mechanism and suggest that the concept of an equivalent radiation altitude has no meaning. 

It also suggests that the amount of positive feedback attributed to water vapour by these global circulation models is impossible and thus that the temperature rise postulated from the predicted increase in carbon dioxide concentration is greatly exaggerated.

2. INTRODUCTION

Greenhouse gases in the atmosphere act entirely through radiative processes.  Earth’s net energy balance is also entirely due to radiative processes since a planet in space can only gain or lose energy by this means.  For these reasons, this paper is primarily concerned with an analysis based on radiative effects. 

While this paper specifically mentions the Kiehl & Trenberth model in some detail (since it is the model used by the IPCC), it is recognised that there are other models also used in modelling, for example, the one quoted in “An introduction to Three-Dimensional Climate Modelling” by Warren Washington and Claire Parkinson ISBN 0-935702-52-0 University Science Books.  While they show some differences compared to the K&T model they seem to share the same basic structure of low radiation from the surface to space and high radiation from the atmosphere to space.  This is the dominant issue being questioned and the K&T model is used here as a convenient example.

3. THE ROLE OF CONVECTION AND LATENT HEAT

This paper is primarily concerned with radiative processes.  This should not be taken as denying the role played by convection and latent heat.  Clearly these processes have enormous effect within the troposphere and indeed are a dominant cause of our weather.  They are also extremely significant in distributing heat around the planet and especially in energy transport from the equator to the poles.

Convection and latent heat effects impact on energy loss to space by changing the temperature versus altitude and latitude profiles within the atmosphere.  The variation in height and temperature of the tropopause with latitude is an example of this.  These represent perturbations superimposed on radiative processes.   While their effects are reduced by averaging over the planet, it is acknowledged that the impact does not entirely cancel out because of the non linear relationship between temperature and energy radiated.  Ignoring these effects thus introduces approximations which reduce the precision of the results obtained.

None the less, it is claimed that the mechanisms discussed in this paper are the dominant mechanisms controlling heat loss from this planet and the conclusions following from the analysis are extremely relevant in assessing the impact of green house gases in the atmosphere.

4. SOME BASIC SPECTROSCOPY

If a material absorbs light, one might intuitively expect the amount of light absorbed to be proportional to the concentration of the material, so that doubling the concentration doubles the amount of light absorbed.  This is not the case as can be seen by a simple thought experiment.  Imagine we have a piece of material which absorbs 50% of the light incident on it transmitting the other 50%.  Doubling the concentration of material is exactly equivalent to adding a second identical piece of the material behind the first piece.  The first piece absorbs 50% of the light incident on it transmitting the remaining 50%.  The second piece being identical does exactly the same, absorbing 50% of the light that passed through the first piece and transmitting 50%.  Thus the net light passing through the two pieces is not 0 but 25%.  If we have n identical pieces the transmission will be 0.5n.

The relationship between concentration and light absorbed is not linear.  Spectroscopists use the term absorbance to define the degree to which a sample absorbs a particular wavelength of light.  Absorbance is defined by  the equations;

Fraction of energy transmitted  =  10 –absorbance
Fraction of energy absorbed     =  1 – 10 –absorbance

If a sample has an absorbance of 1, it means that it absorbs 90% of the light incident on it, transmitting the remaining 10%.  The absorbance of a sample is directly and linearly proportional to the amount of absorbing material in the light path (Beers law).  Thus if a particular sample has an absorbance of 1 then doubling the concentration of the absorbing species for the same path length or doubling the path length with the same concentration will change the absorbance to 2.

5. THE SIGNIFICANCE OF EMISSIVITY

All material substances both absorb radiant energy incident on them, and emit radiant energy at a rate dependent on their temperature.   The degree to which they absorb incident energy is often called the absorptivity and the degree to which they emit energy is often called the emissivity.  However from Kirchoff’s law of thermal radiation the emissivity and absorptivity must be equal to each other.

The absorptivity/emissivity is a property of the substance and its form.  A highly polished surface absorbs and emits less energy than a dull surface and a white surface absorbs and emits less energy than a black surface.  What Kirchoff’s law is stating is that absorption of radiant energy and emission of radiant energy are reciprocal processes, a material that does not absorb will also not emit and vice versa.  The same factor governs both to an equal extent.

Most of the atmosphere is made up of nitrogen and oxygen which do not significantly absorb infrared energy because their emissivity in this portion of the electromagnetic spectrum is exceptionally low.  This means they also do not emit significant infrared – they are not greenhouse gases.  Other gases however have a very strong ability to absorb energy at some wavelengths between 4 and 50 microns (the approximate range of emission wavelengths from earth’s surface).  They are the greenhouse gases and the most significant is water vapour followed by carbon dioxide and then methane and ozone.  Because their emissivity is high at the absorption wavelengths and low at other wavelengths they also selectively radiate energy at these same absorption wavelengths.
 
5. AN ANALYSIS OF THE KIEHL AND TRENBERTH MODEL

This model is documented at;

www.cgd.ucar.edu/cas/abstracts/files/kevin1997_1.html
(from Bull Amer. Meteor Soc, 78, 197-208 1997). 

There is an update dated 2008 at;

 chrisclose.wordpress.com/2008/12/10/an-update-to-Kiehl-and-trenberth-1997/ 

both documents specify very similar numbers.  The K&T model (2008 update) specifies the following energy flows all with the units watts/m2.

Incoming solar radiation   341
Reflected solar radiation   102
Energy radiated from earth’s surface  396
Surface radiation absorbed by the atmosphere 356
Energy radiated from surface directly to space  40
Energy emitted by atmosphere to space  169
Energy emitted from clouds to space   30
Energy transported to atmosphere via
Convection and latent heat  of water vapour  97
Solar radiation directly absorbed by atmosphere 78

This data shows that energy input to the atmosphere via radiative processes = 356 + 78 = 434 watts/m2.  Energy input via convective processes = 97 watts/m2.  Thus energy input to the atmosphere is dominated by radiative processes (82% radiative and 18% convective).

It should also be noted that the global circulation models GCM’s use a concept called the equivalent radiation altitude.  This is a hypothetical altitude from which it is assumed long wave radiation back out to space emanates.  Changes in greenhouse gas concentrations are assumed to change the equivalent radiation altitude.  Changes to this equivalent radiation altitude together with the known lapse rate through the atmosphere are used to calculate changes in surface temperatures.

There is a well known and documented temperature versus altitude data (lapse rate) for Earth’s atmosphere.  This temperature profile is established and maintained by the need for energy balance at every altitude.
 
The lapse rate consists of an almost linear decrease in temperature with altitude from the surface (+14C) to the top of the troposphere – the tropopause (at between 10 – 14 km altitude) where the temperature is between about -60 and   -80 C depending on latitude.  Above the tropopause (in the stratosphere) the temperature rises, again almost linearly, to a maximum of about -20C at an altitude of about 50 km.

The tropopause is thus a cold region sandwiched between warmer regions above and below.  For this situation to be stable (and it is stable), the tropopause must have a way of losing energy to a colder sink – otherwise it would warm up due to energy input from the adjacent regions.  The only colder region available is space itself and the only energy transfer mechanism available is radiative loss.

Thermal emissions from the tropopause will all be in the 5 micron to 50 micron wavelength range (governed by the temperature of the emitter) and can only occur at the characteristic absorption/emission lines of the green house gases.  There is however a problem with this scenario.  Ten percent of Earth’s atmosphere is above the tropopause in the stratosphere and the greenhouse gases in this region would normally absorb the emissions from the tropopause. 

Further, since the air in the stratosphere is warmer, the downwards radiation onto the tropopause would exceed the upwards radiation from it leading to net energy gain not loss.  Yet the tropopause is colder than the stratosphere so it must have a mechanism for losing energy.

A solution to this apparent paradox is that there is an abrupt change in the greenhouse gas composition at the tropopause such that the tropopause can radiate at wavelengths which the stratosphere is not capable of absorbing.  The tropopause represents a temperature inversion which greatly inhibits convection and when that is coupled with the fact that water vapour is carried up from Earth’s surface principally by convection, one would immediately suspect water vapour as the variable component – high concentration in the troposphere and low concentration in the stratosphere.  This suspicion is confirmed by the two quotes taken from the following link;

http://www.metoffice.gov.uk/education/secondary/teachers/atmosphere.html

“The atmosphere is well mixed below 100 km, and apart from its highly variable water vapour and ozone contents, its composition is as shown below”

“As well as a noticeable change in temperature, the move from the troposphere into the stratosphere is also marked by an abrupt change in the concentrations of the variable trace constituents. Water vapour decreases sharply, whilst ozone concentrations increase. These strong contrasts in concentrations are a reflection of little mixing between the moist, ozone-poor troposphere and the dry, ozone-rich stratosphere.”

This information explains how the tropopause can remain colder than the air above and below.  It also explains why temperature rises in the stratosphere.  Ozone is a strong absorber of ultraviolet energy from the sun and such absorption will warm the stratosphere.  The energy gained will be re-emitted as thermal infrared energy at the absorption/emission lines of the greenhouse gases present, mainly CO2 and methane.  The energy absorption by ozone is greatest at around 50 km altitude which is why the temperature peaks at this point and the temperature profile down to the tropopause is essentially an upside down version of what happens in the troposphere.  

It should be noted that the tropopause radiates at all wavelengths corresponding to greenhouse gas absorption/emission lines but those greenhouse gases present in the stratosphere also radiate back down onto the tropopause and since they are warmer, the downward radiation exceeds the upwards radiation.  Thus the only net energy loss from the tropopause occurs at the wavelengths corresponding the water vapour absorption/emission lines.

Since the tropopause can radiate relatively strongly at the water vapour absorption/emission lines (strongly enough to keep itself cold) it follows that the emissivity at these lines must be relatively high which also means that the absorptivity is also high for the reasons discussed in the earlier section titled “the significance of emissivity”.  Couple that with the fact that water vapour concentration is higher at lower altitudes and it follows that the tropopause (possibly together with a small region immediately below it) will be opaque to radiation at the water vapour absorption/emission lines.  That means that emission from lower in the atmosphere directly to space becomes impossible at the water vapour absorption/emission lines because the energy is re-absorbed by the region at or immediately below the tropopause.

The implication is that thermal energy from the surface can escape to space in only two ways.  First, by surface emission escaping directly to space at wavelengths which the greenhouse gases do not absorb.  Second, by emission from the tropopause at wavelengths corresponding to the water vapour absorption/emission lines. 

It is possible to gain at least some idea of the relative magnitude of these two emission mechanisms.

Ozone absorbs essentially all radiation below 290 nanometers (UVC radiation) .  It further absorbs approximately 90% of radiation between 290 and 320 nanometers (UVB radiation) plus a decreasing amount of UVA radiation up to about 350 nm.  The amount incoming solar radiation in these wavelength ranges can be determined by solving Planck’s equation for a 5800K emitter (scaled to 341 watts/m2 total) at wavelength increments of, say, 5 nanometers and then numerically integrating over each wavelength range.  The result is 8.3 watts/m2 for UVC, 6.3 watts/m2 for UVB and 8.3 watts/m2 for UVA up to 350 nm.  The total absorbed by ozone is 8.3 + 0.9*6.3 + 0.5*8.3 = 18.1 watts/m2 .  It should be noted that ozone absorption peaks at around 50 km altitude which should be above most of the albedo effects.

The ultraviolet energy absorbed by ozone is not capable of being re-emitted at the same wavelengths because the gas is too cold.  Instead it will be re-emitted as long wave radiation at the CO2 and methane absorption/emission lines.  For a maximum stratosphere temperature of about -20C the black body radiation between 14 and 15.5 microns is 17.5 watts/m2 which is in reasonable agreement with the calculated energy absorption by ozone.  

The remaining incoming solar energy is either reflected back out to space (due to Earth’s albedo) or is absorbed lower in the atmosphere or at the surface.

The overall albedo of Earth is 0.3 so 341 * 0.3 = 102 watts/m2 is reflected back to space leaving  341 – 102 – 18.1 = 221 watts/m2 to be absorbed at or below the tropopause.  All of this must be radiated back out to space as long wavelength radiation if thermal balance is to be maintained.

There are many water vapour absorption lines below 8 microns.  Between 14 microns and 15.5 microns carbon dioxide absorbs strongly and above 15.5 microns water vapour again has many absorption lines.  Between 8 and 14 microns there is a window where the atmosphere offers little if any impediment to direct radiation to space from the surface. 

Retrieved from http://en.wikipedia.org/wiki/Atmospheric_windows

“The atmospheric window refers to those parts of the electromagnetic spectrum that are, with the earth’s atmosphere in its natural state, not absorbed at all. One atmospheric window lies approximately at wavelengths of infrared radiation between 8 and 13 or 14 micrometres[1].”
[1]   ISBN 0521339561 Houghton, J.T. The Physics of Atmospheres

And;
Retrieved from “http://en.wikipedia.org/wiki/Water_absorption
Cotton, William (2006). Human Impacts on Weather and Climate. Cambridge: Cambridge University Press. ISBN 0521840864. “Little absorption is evident in the region called the atmospheric window between 8 and 14 μm”
Solving Planck’s equation on a spreadsheet for a 288 K source at wavelength increments of 0.2 microns and then numerically integrating yields energies as follows;

Below 8 microns     45 watts/m2
8 microns to 14 microns 143 watts/m2
14 microns to 15.5 microns   28 watts/m2
Above 15.5 microns  174 watts/m2

Interestingly, the energy radiated by Earth’s surface over the strong carbon dioxide absorption band between 14 and 15.5 microns is 28 watts/m2 which is in good agreement with the value typically claimed for the energy retained by carbon dioxide.

It is also important to note that the regions below 8 microns and above 15.5 microns are not totally opaque.  There are multiple absorption lines but there are gaps between these lines where substantial energy can escape to space, especially in the wavelength region above 15.5 microns.  If this were not the case, line broadening through increasing concentrations of green house gases would have little if any impact on incremental energy retention (discussed in more detail later).  This substantially adds to the 143 watts/m2 calculated above.

6. THE IMPACT OF CLOUDS

The above numbers do not allow for the impact of clouds.  Clouds are droplets of liquid water and in the thermal infrared, water has an emissivity very close to 1 (hence the high emissivity of earth’s surface at these wavelengths). It is therefore reasonable to expect clouds to act as grey or black body absorbers with an emissivity approaching 1 as the clouds get thicker.  This would mean that thick clouds would absorb all the thermal infrared energy incident on them and in turn emit energy as a black body from the cloud top.  Since the cloud top is colder than the surface, the energy emitted over the atmospheric window will be lower.  How much lower is easy to calculate by integration of Planck’s law given the known atmospheric lapse rate of 6.5C per kilometer and the height of the cloud.
 
Thin clouds with an emissivity less than 1 would have a smaller impact.

Only a portion of the Earth’s surface at any given time is cloud covered and much of the dense cloud is low altitude cloud, thus a reasonable estimate for the Earth as a whole would be that clouds reduce the energy escaping to space in the atmospheric window by no more than about 15% to 20%.

The radiation from the cloud tops is admittedly no longer radiation directly from earth’s surface but it is still black body radiation and the fraction in the atmospheric window (and in the gaps between the lines at other wavelengths) can still escape directly to space without impediment from green house gas effects.  Thus, while clouds do cause some attenuation, their action does not negate the basis of the hypothesis being presented in this paper.

7. ENERGY RADIATION FROM THE TROPOPAUSE

Earlier discussion suggested that the tropopause can only generate net radiation to space at the water vapour wavelengths which means below 8 microns and above 15.5 microns.

Again solving and numerically integrating Planck’s equation over these wavelengths for a temperature of 213K (-60C) yields a total energy of 82 watts/m 2.  Surface/cloud plus tropopause radiation must equal 221 watts/m2 implying the net energy radiated from the surface and cloud tops would have to be about 139 watts/m2.  However the presence of gaps between emission lines suggests the tropopause radiation will be somewhat lower and the surface/cloud top radiation higher.  When this is taken into account the numbers are entirely consistent with earlier calculations.  Purely as a hypothetical example, if we assume cloud cover causes 15% attenuation and 17% of the energy in the below 8 micron and above 15.5 micron ranges is not absorbed we get;

Surface/cloud emission = 0.85 * ( 143+0.17*(45+174)) = 153 watts/m2
Tropopause emission = 0.83 * 82                                  =   68 watts/m2
Total emission                                                              = 221 watts/m2
 
Water vapour also has very strong absorption bands in the NIR centred at 1.45 microns, 1.95 microns 2.5 microns plus other weaker lines.  There is a significant amount of incident solar energy at these wavelengths and that energy will be rapidly absorbed once water vapour concentration becomes appreciable, which means at or close to the tropopause.  As a consequence, much of the energy emitted from the tropopause is not energy that has percolated up from the surface but rather energy absorbed directly from incoming solar radiation at or near the tropopause.

8. IMPLICATIONS OF THIS ANALYSIS FOR THE KIEHL TRENBERTH MODEL

The global mean energy budget claimed by K&T suggests the vast majority of the energy radiation to space comes from the atmosphere.  It paints a picture of an atmosphere which absorbs almost all surface emissions and then re-radiates a variable amount of this to space.  This implies that slight changes in concentration can vary the fraction emitted thus changing temperatures.  Hence the concept of an equivalent emission altitude and the prediction of a high sensitivity to changes in greenhouse gas concentrations.

The picture emerging from this analysis suggests the opposite, with most of the energy reaching the ground being radiated directly back to space from the surface or cloud tops in the windows between the atmospheric absorption lines.  It implies an atmosphere which blocks almost all the energy radiation from the surface to space at the GHG wavelengths while barely impeding energy radiation to space at other wavelengths.  In this scenario, changing GHG concentrations can only affect warming via line broadening. 

The concept of an equivalent emission altitude is not needed and indeed has no meaning in this scenario.  Energy loss to space from Earth’s surface can only occur directly from the surface/cloud tops or from the tropopause although the relative magnitude of each could change with changing greenhouse gas concentrations.

The very large difference in surface versus atmospheric emission levels predicted from this analysis compared to the Kiehl Trenberth model calls into question the basis of global circulation models based on K&T or other similar data.  It also calls into question the reliability of the output from such models and in the predictions flowing from those models.

It is possible to reinforce this finding by a completely different analysis which is shown below.

9. A SPECTRSCOPIC ANALYSIS OF GREEN HOUSE GAS ABSORPTION

Imagine a single greenhouse gas which absorbs energy at only one specific wavelength.  As the greenhouse gas absorbs energy it heats up until the energy it emits equals the energy it absorbs.  Because it only has significant emissivity at the absorption wavelength the energy will be re-emitted at this wavelength. However, the emitted energy will be emitted in all directions.  Since the atmosphere is a thin continuous shell covering the entire earth it has only two surfaces, an inner surface adjacent the planet itself and an outer surface adjacent to space.  Radiation leaves the atmosphere through one of these two surfaces.  Thus, radiating in all directions in effect means 50% will be emitted towards space and 50% returned to the planetary surface.

A very simplistic first approximation would be to say if the absorbance of the gas column is N then the gas absorbs 1- 10-N per unit of the incident energy and 50% of this is returned to the earth’s surface giving an effective energy retention of

Energy retained = 0.5*(1-10-N).  (1)

That may be correct when N is very small (<<1) but is grossly in error for higher absorbances because it ignores repeated re-absorption and re-emission of energy within the gas column.

As the absorbance of the gas column rises, repeated absorption and re-emission becomes very significant.  In this context we must again remember that the same emissivity covers both absorption and emission so that emitted energy will be predominantly at the absorption wavelengths thus facilitating repeated absorption and re-emission.  By the time the atmospheric absorbance has reached 1,   90% of the energy at the absorption wavelengths is being absorbed which also means that much of the energy emitted by the atmosphere will be re-absorbed within the atmosphere, possibly going through several absorption re-emission cycles within the atmosphere.
 
To analyse this situation, imagine we treat the entire gas column as stack of 1 absorbance layers.  As a first order approximation, assume that each layer absorbs all the energy it receives from above or below and maintains itself in thermal equilibrium by emitting an equal amount of energy, half towards the surface and half away from the surface.  The result is shown diagrammatically for an N absorbance atmosphere.

 

Where

E1 is the total energy absorbed by layer 1
E2 is the total energy absorbed by layer
En is the total energy absorbed by layer n
EN is the total energy absorbed by layer N

Equations (2) to (5) are obtained by summing energy into each layer.

Substituting (2) into (3) gives E2 = 2 * E3 / 3 (6)
Rewriting (4) with n=3 and then
Substituting (6) into it gives E3 = 3 * E4 / 4 (7)

In general for the nth layer En = n/(n+1) * En+1 (8)
Replacing n by n-1 in (8) gives En-1 = (n-1)/n * En (9)

 

 

 

 

 

  

 Since equn (9) holds for any n we can replace n by N to get
From (9) EN-1 = N-1/N * EN
Substituting into (5) gives EN = (N-1)/2N * EN +1
And rearranging EN = 2N/(N+1) (10)

If we expand (8) as a series we get;
En = n/n+1 * En+1
     = n/n+1 * n+1/n+2 * En+2
     = (n/n+1) * (n+1/n+2) * (n+2/n+3) *…* (N-1/N) * EN

Cancelling common terms gives En = n/N * EN (11)

Substituting for EN from equn (10) gives
En = 2n/(N+1)

The energy radiated away to space is 0.5 * E1 = 1/(N+1)    (12)
The energy returned to the earths surface is 0.5* EN = N/(N+1)   (13)

 Equations 1 and 13 are plotted below. Interestingly, even below 1 absorbance equation 13 gives essentially the same result as equation 1 and can thus be treated as a reasonable approximation over the entire absorbance range.

 

 

 

 

 

 10. INTERPRETATION OF THESE RESULTS

Heinz Hug (http://www.john-daly.com/artifact.htm) has measured the absorbance of the atmospheric column of CO2 at 280 ppm and reports a total absorbance in excess of 2000. The above calculation suggests that the fraction of energy at the absorbing wavelength which is radiated to space is only 1/2001 or 0.05%. This is in agreement with the analysis derived from the temperature versus altitude profile.

In the case of water vapour, it is only necessary to note that Fourier transform infrared spectrometers with an optical path length of well under 1 meter need to be either purged with dry gas or packed with desiccant and sealed in order to avoid unacceptably high energy loss from water vapour absorption and that the troposphere is 10,000 meters thick (more than 10,000 times the path length) to realise that a similar situation exists for water vapour.

11. THE IMPACT OF LINE BROADENING

Both of the above analyses suggest that greenhouse gases almost totally block energy loss to space at their absorption/emission wavelengths. This implies that significant energy loss from the surface or cloud tops is by direct radiation to space at wavelengths where the greenhouse gases do not absorb. Given that, one might be tempted to conclude that since the greenhouse gases already absorb everything they can, further increases in concentration should have no impact. This is not the case because of an effect known as line broadening.

The absorption versus wavelength profile for a green house gas line does not have infinitely steep sides. As concentration rises the line centre will saturate but absorption out in the wings of the line are not yet saturated. Further increases in concentration have no impact on the behaviour at the line centre but do slightly increase absorption out in the wings. In effect the line slowly broadens as the concentration increases. It is this effect that gives rise to the well known logarithmic relationship between concentration and energy absorbed.

In fact, the unsaturated lines of greenhouse gases are so narrow and therefore absorb so little energy, that the overall impact of a greenhouse gas does not become significant until the line centres saturate and the line start to broaden. This means that all greenhouse gases of significance are likely to display the logarithmic relationship between concentration and energy absorbed.

As the lines broaden they further constrict the wavelengths at which radiation can escape from Earth’s surface to space. For the same energy to be emitted from a narrower window implies higher energy density at the remaining wavelengths which implies a higher surface temperature.

In the case of carbon dioxide, the IPCC in their fourth assessment report stated that the increase from 280ppm to 390 ppm increased energy retained by 1.77 watts/m2. Applying the logarithmic relationship;

1.77 = n * log (390/280)
from which it follows that n = 12.3.

The increase from 390 ppm to 560 ppm (2070 projection from IPCC 4th assessment report) would increase retained energy by 12.3 * log (560/390) = 1.93 watts/m2 . Applying Stefan’s law at 288 kelvin (+14C) we find that each degree rise in temperature takes 5.4 watts/m2 . Thus the direct effect of the rise in carbon dioxide is 1.93/5.4 = 0.36C.

IPCC inflates this to about 3C by assuming massive positive feedback from water vapour. A 3C rise implies an additional 16.2 watts/m2 of which 16.2 – 1.93 or 14.3 watts/m2 must be coming from water vapour. The CRC handbook of chemistry and physics shows that water vapour content at constant humidity rises exponentially with temperature roughly doubling for each 10 K rise in temperature. This can be expressed as

water vapour concentration is proportional to 10 (temperature/33.2)

A 3C rise in temperature increases water vapour concentration by 10 (3/33.2) = 1.23 (23%). Applying the same calculations as for carbon dioxide

14.3 = m * log (1.23) from which m = 159 and each doubling of water vapour changes energy retained by 159 * log(2) = 48 watts/m2 .

The earlier Planck’s law calculations suggested water vapour at +14C retains at most 219 watts/m2 (in fact less when one allows for gaps between absorption lines). Coupling that with the CRC handbook data that water vapour doubles or halves for each 10C change in temperature, a sensitivity of 48 watts/m2 per doubling implies the following;

14C energy absorbed/emitted <219 watts/m2
+4C energy absorbed/emitted < 171 watts/m2
-6C energy absorbed/emitted < 123 watts/m2
-16C energy absorbed/emitted < 75 watts/m2
-26C energy absorbed/emitted < 27 watts/m2
-36C energy absorbed/emitted      0 watts/m2

This is completely incompatible with water vapour radiating substantial amounts of energy at -60C which is necessary to explain a cold tropopause.

12. CONCLUSIONS

Both the analysis from basic spectroscopy and the analysis based on atmospheric lapse rates give similar results and imply that greenhouse gases almost totally block energy loss to space at their absorption/emission wavelengths. That in turn suggests that a very significant portion of the energy loss from Earth’s surface is by direct radiation to space at wavelengths where the greenhouse gases do not absorb.

This is in conflict with the Kiehl & Trenberth model and other similar models which suggest that most of the energy loss to space is from the atmosphere. If the atmosphere emits little energy, and then largely from the tropopause and stratopause, the concept of an equivalent radiation altitude has no meaning. Further, the analysis suggests that most of the radiative energy loss from the atmosphere to space is re-radiation of solar energy absorbed high up in the atmosphere.

Surface temperature will increase with increasing greenhouse gas concentrations due to line broadening. The direct effect of carbon dioxide (in the absence of any feedbacks) using the IPCC quoted sensitivity and their postulated rise in carbon dioxide from 390 ppm to 560 ppm will contribute 0.4 degrees by 2070. The IPCC claim that positive feedback from water vapour will increase that to about 3C would imply a sensitivity of 48 watts/m2 per doubling in water vapour concentration. Such a high sensitivity is not compatible with the observed atmospheric temperature versus altitude profile.

It should be noted that this analysis does not predict no radiation to space at the greenhouse gas absorption lines. There is still energy at these absorption lines emitted to space. For the well mixed greenhouse gases such as CO2 and CH4 this energy largely emanates from the stratosphere and is powered significantly by UV absorption of incoming solar radiation by ozone plus some absorption of surface radiation at 9.6 micron . In the case of water vapour, the energy emanates from near the tropopause and is powered significantly by near infrared absorption of incoming solar radiation by water vapour.

**************

Michael Hammer graduated with a Bachelor of Engineering Science and Master of Engineering Science from Melbourne University. Since 1976 he has been working in the field of spectroscopy with the last 25 years devoted to full time research for a large multinational spectroscopy company.

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285 Responses to “Radical New Hypothesis on the Effect of Greenhouse Gases”

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  1. Comment from: Luke


    Well golly Jae – :-o

    if there is no “radiative balance” – how come we don’t heat up to 100C or freeze – to -100C – NEXT !

    And if you don’t like global averages try solving for a smaller grid box – 1km? 500m? 30m? gee maybe that’s what even happens – NEXT !

    Gordon – as soon as you write ONE physical equation – you’re modelling ! Look out !

  2. Comment from: jae


    Luke: Judging by your judgemental and unsubstantive comments, it appears that you are not a scientist (you like that ad-hom, you little phony fella??), and you really don’t deserve an answer, given your snarling, leftist, authoritative attitude. But, what the hell, what is wrong with asking you to refute this idea? Maybe the reason El Nino’s occur is because there is no general “energy balance.” The Earth’s energy system is probably never in “balance.” It stores heat for awhile and then “dumps” it, which is exactly what an El Nino is. And that is also exactly what a thunderstorm does. Please explain to us how you come up with an “average radiation” when you are dealing with fourth power relationships (I hope you understand the question, but I doubt it).

  3. Comment from: jae


    Luke sez:

    “Gordon – as soon as you write ONE physical equation – you’re modelling ! Look out ”

    Correct. But if you present the results of that equation as DATA, without verifying it, LOOK OUT, because you are probably a “climate scientist.” Show us that the GCMs are “on target,” given the last 10 years of no warming, Luke. With references, if you can find any. Read Lucia’s blog first, then report back here.

  4. Comment from: Gordon Robertson


    jae “I think it is all about energy storage, not radiation balances. That explains the presence of ENSO, AMO, etc.”

    Makes a lot more sense to me too, but beware. As cohenite points out, they’re after us.

  5. Comment from: jae


    I would appreciate it very much if someone would respond to my comment about the propane torches. Why can’t I melt steel with 100 air/propane torches directed at the same spot? I’ve posted a similar question probably 10 times, and nobody has yet responded. Just silence. WTF?

    Someone should be able to tell me how you can add watts from ice and hot rocks to come up with a “total radiation,” from which you can use SB to calculate an “average global temperature.” Why all the silence about this question?????? Am I that insane that nobody will respond????

    I welcome being “put down.” Give me your best bender talk!

  6. Comment from: Michael Hammer


    I am on a very slow internet facility with limited time so I will not be able to respond to everything. Anyway about 50 posts in the last day is quite a lot to respond to.

    Nick; you claim you never suggested my thesis was little different from the K&T model. With resect I disagree – read your earlier posts.

    As to suggesting that I am chainging my story all the time. Again I most strongly disagree. You say you don’t understyand what I mean so I try to find a different way to explain it to you and then you say its changing my story. I have seen this tacfic used frequecny to try and unsettle a debater . I won’t say more on that subject.

    ON this site I can’t scroll up and down readily to review everything you wrote so if I miss some points my apologies – my memory is not good enough to remember your entire text.

    The bottom line is that I think the 169 figure is too high and the 70 too low. I give my estimates in my original paper. Why to I think K&T came up with such a low fiure for radiation from earth/clouds? Because they assuem a window from 8-12 microns when it is more like 8-14 microns and they assume zero net radiation from the surface or clouds at any other wavelength. Every other paper I have read on the subject talks about a picket fence of lines with energy slipping out between the lines. It5s a very hand waving way of describing things but not my words. It does however imply gaps between the lines where energy can escape to space. K&T ignor this and take it to be zero. I thik that is an error.

    On to other things, someone asked me about whether or not I believe in down welling radiation. The best answer I can give is that you are thinkingn about things in a way that will confuse you. Any object if above absolute zero and with an emissivity above 0 will radiate . It makes no difference is the object it is radiating to is hotter or colder, how wold the radiator know the tejmperature of tyhe object it is radiating to? So yes there will be radiation directed back towards the sruface. Now how do I reconcile that with the implication that the colder object is radiating back to a hotter object? Simple, the hotter object is also radiating and because it is hotter it is radiating more than the colder one. Thus the cold object is radiating to the hotter object but it is in turn recieving more radiation from the hotter object that it emitted. Thus the net heat flow is from hotter to colder not vice versa but both are radiating. This means there IS downwelling radiation.

    I hope this makes things a bit clearer. I am running out of time so I will have to stop now. Will try to write more tomorrow – hopefully from a faster internet connection.

  7. Comment from: michael hammer


    Reading through my previous psot I note there are many typos. Apologies, but on this computer I can’t scroll up or down to review at anything other than a pace which makes a sleeping snail look really speedy and I never was a good touch typist.

  8. Comment from: cohenite


    luke; you are being slippery; tell me, do you and AGW assume a radiative balance for the Earth which anthropogenic influence is upsetting?

    As for EOF and no solar influence adequate to explain the warming from 1850; actually it’s from the end of the little ice age a bit before 1850; and Drew Shindell’s NASA piece which I have linked to a number of times shows the solar influence there; anyway so does any one of Bob Tisdale’s analysis’s of the various sea surface temperature acronyms; here’s one;

    http://wattsupwiththat.com/2009/03/05/ipcc-20th-century-simulations-get-a-boost-from-outdated-solar-forcings/#more-6046

    More to the point, here is a PR paper by Shariv which lands another solar/cosmic ray power stake through the ideology of AGW;

    http://landshape.org/enm/was-the-younger-dryas-caused-by-cosmic-ray-flux/

    This is a political argument now; in fact, it never was about the science as my paper at Jennifer’s community section points out; go and pull it to bits luke.

  9. Comment from: Gordon Robertson


    SJT “Radiative equilibrium was not ‘foisted’ on anyone by modellers, it is one of the fundamental physical properties of the Earth energy equation, or any energy equation for that matter, and long predates the modellers”.

    I don’t know what you mean by ‘pre-dates’. Modeling of atmospheric and oceanic systems go back to the 1960′s. That’s when attempts were first made to encapsulate the atmosphere in a model. Dr. Joanne Simpson was using cloud models back in the ’50s or ’60′s. Besides, the link you provided points to a model. BTW…Dr. Simpson claims todays models are not reliable.

    Seriously, how do you think they studied the atmosphere initially? They had no satellites and nothing more than weather balloons. Dr. Simpson was one of the first meteorologists to fly into weather systems to observe them directly. There was nothing other than models and that’s where radiative equilibrium theory originated. When computers became available in the 1960′s, that’s when modeling theory took off, and it allowed mathematicians to encroach on physics theory.

    When I was younger, I hung around with a guy who was seriously into meteorology as a hobby. He was up all hours of the night on a short-wave radio listening to weather broadcasts and would ride his bike about 15 miles out to the local airport to schmooze with real weathermen. No one talked about radiative balance back then and it was never taught in high school science classes, although basic meteorology was taught. Climate science was not even a recognized discipline till the 1970′s or 80′s, so I can’t imagine studies about radiative equilibrium being an issue in the atmosphere till then.

    As G&T point out, there is nothing in physics theory that back up the radiative balance theory. They have this to say:

    “…from the viewpoint of theoretical physics the radiative approach, which uses physical laws such as Planck’s law and Stefan-Boltzmann’s law that only have a limited range of validity that definitely does not cover the atmospheric problem, must be highly questioned.”

    Then they add:

    “For instance in many calculations climatologists perform calculations where idealized black surfaces e.g. representing a CO2 layer and the ground, respectively, radiate against each other. In reality, we must consider a bulk problem, in which at concentrations of 300 ppmv at normal state…N ~ 8 x e6 CO2 molecules are distributed within a cube V with edge length 10 microns, a typical wavelength of the relevant infrared radiation. In this context an application of the formulas of cavity radiation is sheer nonsense”.

    They are implying that blackbody radiation calculations are nonsense under the conditions we encounter in the atmosphere from the standpoint of physics. Where then does the radiative balance theory come from? The only other source is climate science, particularly from model theory. To be more precise, the theory was highly popularized by the IPCC, which based it’s findings exclusively on computer model theory.

    The concept of replacing the Earth’s surface and atmosphere with imaginary blackbody surfaces, then applying one-line drawings to represent heat flow, is a model, plain and simple. The thing that’s so amazing is the questioning of satellite data that refutes the models. The sheer arrogance that goes into implying that a toy-like model is correct, and a directly observed temperature is wrong, borders on madness. Yet the IPCC is willing to encourage that madness.

    G&T also make this point:

    “…it is misleading to visualize a photon as a simple particle or wave packet travelling from one atom to another for example. Things are pretty much more complex and cannot be understood even in a (one-)particle-wave duality or Feynman graph picture”.

    This is exactly what Bohren says in the Fundamentals of Atmospheric Radiation. We have been inundated with the severely simplified notion that the Earth’s warmed surface fires a photon into the atmosphere and that it is trapped by a waiting GHG atom or molecule. Then the trapped photon is back-radiated, warming the surface more. Some, like yourself, think the heat is somehow stored.

    No one knows what a photon is, and as G&T imply, the theory surrounding them is complex. Bohren and Clothiaux go to great length in their book explaining the emission, absorption and scattering of photons in the atmosphere, taking entire chapters full of complex math to explain their idealized action. In the end, they draw no conclusions while fully discrediting the heat trapping mechanism of GHG’s in the atmosphere and reducing the back-radiation theory to a hypothetical situation. And they are experts.

  10. Comment from: Gordon Robertson


    cohenite “here is a PR paper by Shariv…”

    It’s tough to remember the guys name…it’s Shaviv. It’s interesting that he is a convert from the AGW theory to being a skeptic. He’s also an astrophysicist like Hansen. Where did Hansen go so wrong?

    I also noted that a comparison is being made between Shaviv’s work and Miskolczi (even harder name to remember). Keep pounding away, cohenite, we’ll get the latters work recognized yet.

  11. Comment from: Nick Stokes


    Michael,
    I realised on following up your post that K&T actually never say that 40 (or 70) W/m2 is the amount of IR that goes through to space unimpeded. They do just say that it’s the amount that goes through the atmospheric window as they’ve defined it (8-12μ). The fact that you’ve used a larger window and got a different figure is not necessarily surprising.

    I did say in my original post that the amount that goes through unimpeded is hard to pin down and not particularly important. The reason is that the fraction of the spectrum that is able to be affected by increased GHG is distributed (on the fringes of absorption bands) and can only be computed by an accurate LBL calc. The band centres are “saturated”, and the AW and its fringes do not block much at all, even with increased GHG. The intermediate redions are various shades of grey. So just a block AW calc doesn’t answer that question.

    I liked your explanation of down-welling IR.

  12. Comment from: cohenite


    Thanks Gordon; my only excuse is that luke’s acronyms confuse me after a while; have a look at this;

    http://jennifermarohasy.com/blog/2009/03/introducting-the-climate-sceptics-a-new-political-party/#comments

  13. Comment from: Gordon Robertson


    jae “I would appreciate it very much if someone would respond to my comment about the propane torches. Why can’t I melt steel with 100 air/propane torches directed at the same spot”?

    Never seen your question before and I’m just stabbing in the dark. Propane doesn’t burn at a high enough temperature and there’s no pure oxygen to make it burn hotter. Probably the same reason you could never burn enough matches to do the same thing. Here’s a clip of the Sun melting steel via a mirror system:

    http://www.neatorama.com/2008/11/03/melting-steel-with-the-sun/

    I have been asking the same kind of question myself, regarding the addition of heat quantities. Your question of an average global temperature is one I have been asking as well. Let me know if you get an answer.

  14. Comment from: Luke


    Cosmic rays – hahahahahaha – oh that hurts…

    Cohenite you lot believe in everything under the Sun…. hahahahaha – the Sun get it – hahahahaha

    Cohers – EOF (Empirical Orthogonal Function) from PCA (Principal Component) analysis . Just basic stuff.
    Indeed I asked Prof Decadal about the current “stasis” in temperatures – he looked aghast and said GCM runs typically have such periods. Don’t confuse means with an individual instantiation or indeed the real world. You’d need 15 years of zero growth or cooling before you’d get even slightly excited.

    Jae still doesn’t get it – models don’t solve the radiation problem globally. The old Lubos 4th power scam eh?. LOLZ ….NEXT !

    The real action will be when Hadley gets one model from daily to decadal to climate change scale (say 1000 year integration). Indeed if they can get the resolution small enough new physics will even start to kick in.

    Hey Cohers if you lot get published (hahahahaha) you might be able to even contribute. Remember if it’s not published it’s all just noise on the wire.

  15. Comment from: SJT


    “On to other things, someone asked me about whether or not I believe in down welling radiation. The best answer I can give is that you are thinkingn about things in a way that will confuse you. Any object if above absolute zero and with an emissivity above 0 will radiate . It makes no difference is the object it is radiating to is hotter or colder, how wold the radiator know the tejmperature of tyhe object it is radiating to? So yes there will be radiation directed back towards the sruface. Now how do I reconcile that with the implication that the colder object is radiating back to a hotter object? Simple, the hotter object is also radiating and because it is hotter it is radiating more than the colder one. Thus the cold object is radiating to the hotter object but it is in turn recieving more radiation from the hotter object that it emitted. Thus the net heat flow is from hotter to colder not vice versa but both are radiating. This means there IS downwelling radiation.”

    Many thanks, I hope other people on this website read it and learn.

  16. Comment from: cohenite


    You can be a right goose sometimes luke; PCA, Mann’s backside; “you need 15 years of zero growth or cooling before you’ get even slightly excited”;

    http://woodfortrees.org/plot/gistemp/from:1940/to:1977/trend/plot/gistemp/from:1940/to:1977

    There you go; don’t wet your knickerbockers.

  17. Comment from: Marcus


    luke
    “new physics will even start to kick in.”

    You sir are off your rocker!
    The hysterical “hahahaha” just proves it beyond doubt.

  18. Comment from: Phillip Bratby


    Michael, Gordon Robertson, jae, cohenite: Thank you all for some very perceptive comments and reasoning. If only someone had the time to pull it all together into an easily understood paper.

    Please.

  19. Comment from: Jan Pompe


    Nick “. The reason is that the fraction of the spectrum that is able to be affected by increased GHG is distributed (on the fringes of absorption bands) and can only be computed by an accurate LBL calc.”

    That is precisely what Ferenc Miskolczi has done using HARTCODE and come up with the comparitively simple St = Su * exp (-tau) which bears a striking resemblance to Beer-Lambert law and Michael’s derivation. It’s just the value of tau that needs to be determined accurately with an LBL. All that Miskolczi did with the LBL is verify that generally absorbed radiation (Aa) = downward emitted radiation (Ed) so that Ed is actually a good proxy for Aa and hence you can go out with a pyrgeometer and if there is no howling gale (indicating sever inequilibrium) measure upward radiation and downward radiation and the difference will be St. (St = Su – Aa).

  20. Comment from: SJT


    “There you go; don’t wet your knickerbockers.”

    The models work on known physics and anthropogenic forcings. During that time particle pollution caused some global dimming, and current models match that event. I don’t know what your point is.

    Do you agree with Hammer on downwelling radiation?

  21. Comment from: cohenite


    Little will; good to see you back and running interference; the aerosol excuse for the cooling period I graphed is a farce; if aerosols had been responsible for the cooling we would have seen a hemispheric difference in temperature since the northern hemisphere was where 99% of the aerosols were being industrially produced; but we didn’t, the 40′s-70′s cooling was evenly spread; in addition, aerosols haven’t declined in the 80′s and 90′s; the output in the tiger economies, particularly India and China have more than compensated for the Western decline; that being the case, why did we we have warming in the 80-90s?; furthermore, it is not at all well established that aerosols uniformly cool;

    http://www.agu.org/pubs/crossref/2007/2007GL030380.shtml

    See also the work of Veerabhadran Ramanathan.

    I have never said that GHGs do not reemit isotropically; what I argue is that the downward emission cannot heat the warmer surface which has emitted to the atmospheric gases; Jan explains why above.

  22. Comment from: Jan Pompe


    Gordon: “Never seen your question before and I’m just stabbing in the dark. Propane doesn’t burn at a high enough temperature and there’s no pure oxygen to make it burn hotter. Probably the same reason you could never burn enough matches to do the same thing. Here’s a clip of the Sun melting steel via a mirror system:”

    I think jae is specifically looking for an answer from a specific person who has ducked the same question elsewhere.

    My hobby is making jewellery and I know not to try soldering/welding platinum with anything less than a oxy-hydrogen torch (yes I have one that will burn anything from lpg to Hydrogen). The reason is the burn temperature of a propane torch is around 1300C and the melting point of Iron is 1538C in order to do work with it (like welding) you need a very much hotter temperature source in order to be able to keep the melt local. You can get higher temperature with oxygen (~1900C) still not hot enough for welding where we need more concentrated heating but it’s OK for brazing. My gaz of choice is Acetylene since both hydrogen and platinum are too expensive for a hobbyist (gold is getting that way too :-(.

    The sun is a different matter it’s surface temperature is 5688K but can’t heat objects at earths orbit to more than about 400C because of the inverse square law i.e. the energy density decreases, but some of the energy density can be regained with concentration (with mirrors and lenses) yet the limiting temperature that can be attained is 5788K.

  23. Comment from: SJT


    “I have never said that GHGs do not reemit isotropically; what I argue is that the downward emission cannot heat the warmer surface which has emitted to the atmospheric gases; Jan explains why above.”

    Fine. Let’s move on to the next step. A photon is re-emitted from a GHG molecule, and strikes the earth. What happens to the energy from that photon?

  24. Comment from: cohenite


    ED = SU [1 - TA] for all places.

    Now you quid pro quo little will;

    What the R2 correlation between CO2 and temperature?

  25. Comment from: Jan Pompe


    SJT: “What happens to the energy from that photon?”

    it is absorbed has a bit of energy added to it and re-emitted the thing is more energy is emitted from a warmer surface than it absorbs from cooler source.

  26. Comment from: SJT


    “it is absorbed has a bit of energy added to it and re-emitted the thing is more energy is emitted from a warmer surface than it absorbs from cooler source.”

    Yes, but the process of emitting that energy to space has been effectively slowed down, has it not?

  27. Comment from: Jan Pompe


    SJT “Yes, but the process of emitting that energy to space has been effectively slowed down, has it not?”

    It has but all that does is smooth out the variations it does not out more heat into the system that remains a constant – more or less if all other things are constant.

  28. Comment from: SJT


    It’s not smoothing out variations, it’s slowing up the release of heat from the surface of the earth to space in the atmosphere. If there is more energy in the atmosphere because of this physical process….

  29. Comment from: Jan Pompe


    SJT “It’s not smoothing out variations, it’s slowing up the release of heat from the surface of the earth to space in the atmosphere.”

    The heat in the system is limited by the incoming from the sun try not to confuse heat and energy they are not the same. The effect is similar to to putting a capacitor across a pulsating DC line it smooths it out and doesn’t increase the average (RMS) potential. That is there are lower peaks and higher troughs.

  30. Comment from: SJT


    I’m not confusing anything. Heat is stored energy, an energy flux is the movement of that energy.

    You always screw up those eletrical circuit analogies. The heat in the system is limited by the incoming energy, and the release of that energy. You need a resistor in their somewhere. Turn up the resistance, and the energy is released more slowly, accumulating more energy in storage.

  31. Comment from: Jan Pompe


    SJT “I’m not confusing anything. Heat is stored energy, an energy flux is the movement of that energy.”

    You are horribly confused. Heat is energy transfer not stored energy.

    You could at least try google before shooting from the hip.

    “You need a resistor in their somewhere.”

    Yes indeed and that resistor is made smaller by the addition of GHG without which energy cannot leave the atmosphere or enter the atmosphere efficiently. The capacitor is the atmosphere and GHGs one of the pipelines in and the only pipeline out.

  32. Comment from: jae


    Gordon:

    “jae “I would appreciate it very much if someone would respond to my comment about the propane torches. Why can’t I melt steel with 100 air/propane torches directed at the same spot”?

    Never seen your question before and I’m just stabbing in the dark. Propane doesn’t burn at a high enough temperature and there’s no pure oxygen to make it burn hotter. Probably the same reason you could never burn enough matches to do the same thing. Here’s a clip of the Sun melting steel via a mirror system:”

    Gordon, the question relates to radiation cartoons, like K&T 97, which show 390 watts leaving the surface, 325 of which come from “back-radiation.” Now, I certainly don’t disagree that there is back-radiation; however, I fail to see how you can add it to the heat coming from the surface to arrive at a “global average temperature.” 325 w would be released by a surface at about 0 C, IIRC.

    If you can add wattages like this, then I should be able to melt steel by using several air/propane torches (i.e., adding the wattages for all of them together to produce a high enough temperature). I cannot do that. Therefore, I cannot add the 325 watts to the 65 watts from the surface to get the magic 390 watts that supposedly represents the “global average surface temperature” (a concept that is also crazy, for reasons stated earlier).

    As jan noticed, at least one of the contributors seems to be refusing to address this question.

    BTW, those interested in the nature of photons should look at the U-tube presentations on Lubos Motl’s site, Cassiopeia Project: http://motls.blogspot.com/

  33. Comment from: SJT


    Whoah, how much wine have I drunk tonight? Not quite enough to believe I am reading what you just wrote.

    The atmosphere gases are pretty much transparent to incoming shortwave radiation from the sun, and the GHGs are opaque to various frequencies of radiation going out. They are not ‘pipelines’ at all, but inhibit the transfer of radiation. They don’t stop the radiation, it eventually all gets out, but only after being delayed.

  34. Comment from: Jan Pompe


    SJT “The atmosphere gases are pretty much transparent to incoming shortwave radiation from the sun, and the GHGs are opaque to various frequencies of radiation going out. They are not ‘pipelines’ at all, but inhibit the transfer of radiation.”

    The do not inhibit transfer of heat from the surface to the atmosphere without GHG the atmosphere would warm more slowly without GHG the atmosphere will not cool at the tropopause. That is they assist in warming the atmosphere and are the only means of cooling.

  35. Comment from: jae


    SJT: You have to consider thermalization, also, not just radiation. The GHGs absorb the IR, then collide with the N2 and O2 molecules, thereby “warming” them, also. When the molecules get warmer, they rise (convection) and spread that heat ever higher and higher in the atmosphere, until the heat gets radiated back to space. As Mike Hammer points out, a lot of the IR simply goes directly to space and GHGs have no effect on that portion.

    The backradiation from GHGs slows down the release of heat, but it does not increase the amount of heat in any way. Thus, an increase in GHGs could raise the AVERAGE temperature, by slowing down the cooling (warmer nights), but I doubt that they increase the absolute heat levels. If they could, the tropics would be a hell of a lot hotter than the deserts on a clear day; but the reverse is true.

  36. Comment from: Fresh Bilge » FB Non-Randoms


    [...] Greenhouse effect: warmists got the science wrong from the start. [...]

  37. Comment from: Graeme Bird


    “One problem I see with trying to discuss everything in terms of “radiative balance” is that there does not have to be such a balance. Energy is conserved, but power (radiation) is not. The whole idea of AVERAGING the amount of solar radiation received–or the amount of radiation leaving the planet doesn’t make sense to me. Because of the fourth power dependence of radiation on temperature, averages don’t make any sense at all. Extra heat is stored in the tropics and that is shared with the higher latitudes. I think it is all about energy storage, not radiation balances. That explains the presence of ENSO, AMO, etc.”

    Exactly right. Aggregation and averaging in one way only takes the climate out of climate science.

    You have to find the appropriate level of aggregation and not use the one angle all the time. We ought to be thinking far more the flow of joules and not the balance of watts.

    Or at least we ought not think in watts all the damn time. That gives us a perspective of about one second. When the problem we have at hand is the pretended prospect of CUMULATIVE catastrophic warming. And cumulative warming has to outlast a solar cycle or two. Its not something decided on a time horizon of seconds.

  38. Comment from: Luke


    Hey Graeme – your fly is undone mate.

  39. Comment from: spangled drongo


    If this doesn’t get published by a climate science journal it will show how pathetic they are.
    Just as Paltridge et al couldn’t get published with their paper on NCEP data on tropospheric humidity implying, contrary to GCM predictions, that long term water vapour feedback is negative, that it would reduce rather than amplify the response to atmo CO2.

    Bore it up ‘em, George Will!

    http://wattsupwiththat.com/2009/03/08/george-will-qa-on-his-recent-column/#more-6083

  40. Comment from: SJT


    “That is they assist in warming the atmosphere and are the only means of cooling.”

    If there were no GHGs, the radiation from the surface would go straight out to space. The atmosphere would be a lot colder. At least you acknowledge that a GHG causes the atmosphere to warm. If you have more GHG in the atmosphere…….?

  41. Comment from: SJT


    “As Mike Hammer points out, a lot of the IR simply goes directly to space and GHGs have no effect on that portion.”

    But we already knew that.

  42. Comment from: gavin


    There hasn’t been much discussion on the relative heat quanties and losses relative to the surface air mass, nor is it easy to get the warming math into perspective

    For starters, I wondered about the magnitudes of temp gradient change including switches in other layers as we go out from the troposphere based on composition. Given it’s pretty thin beyond jet altitudes I claimed most of the warming is occuring below the clouds, but at what altitudes do the GHG’s cease to impact on ST? Where indeed is visible light the clue?

    Anyone else needing a physics revision and an update on the global electrical circuit or blue skies analysis can look here in this “Aviation Meteorology Guide”

    http://www.auf.asn.au/meteorology/section1a.html

  43. Comment from: cohenite


    “If you have more GHG in the atmosphere….” nothing happens; it’s called the logarithmic effect and asymptopic negligibility. Interesting to see that the EG and the +ve feedback from water claptrap a la Dessler has got its due dessert;

    http://landshape.org/enm/are-changes-in-water-vapor-consistent-with-the-models/#comments

  44. Comment from: SJT


    You agree then that GHGs warm the atmosphere, and downwelling radiation is a part of this effect? Could you please let some of your colleagues know? They seem a little dubious of this basic science?

    Logarithmic seems to have come to mean “nothing”. Must some kind of new maths.

  45. Comment from: Jan Pompe


    SJT” “If there were no GHGs, the radiation from the surface would go straight out to space. The atmosphere would be a lot colder.”

    You seem to think that GHGs is the only way that the atmosphere warms. If so you have it back to front it is the only way that the atmosphere can shed heat to space.

  46. Comment from: Jan Pompe


    BTW folks the G&T paper has now been published in International Journal of Modern Physics B

    http://www.worldscinet.com/journals/ijmpb/23/2303/S021797920904984X.html

  47. Comment from: SJT


    “You seem to think that GHGs is the only way that the atmosphere warms.”

    I don’t recall saying that. Read what I said again. The atmosphere is pretty well transparent to short wave radiation. That is how it gets to the surface and heats it. The long wave length radiation from the surface, if it did not encounter GHGs, would once again travel straight out to space again.

  48. Comment from: SJT


    “BTW folks the G&T paper has now been published in International Journal of Modern Physics B”

    That’s funny. I would love to know how they scammed that one. For one thing, the Journal has nothing to do with climate. For another, it looks like it uses an internet based public submission system. Maybe they found a back door to get it in there.

  49. Comment from: Jan Pompe


    SJT ““You seem to think that GHGs is the only way that the atmosphere warms.”

    I don’t recall saying that. Read what I said again. The atmosphere is pretty well transparent to short wave radiation. That is how it gets to the surface and heats it.”

    Looks like I got it right. You haven’t got your head around this stuff. You still seem to think that radiation transfer is the only way the atmosphere heats up but it’s the only way it cools. Contact with the surface warms the atmosphere now if there is 20W/m^2 transferred to the atmosphere and zero can leave for 4 billion years what do you think the temperature of the atmosphere would look like?

  50. Comment from: SJT


    I say: A.
    You say: B.
    I say: I wasn’t talking about B, I was talking about A.
    Your say: Yeah, but what about B.
    I say: If you want to talk about B, fine, but I thought we were talking about A.

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