Is Measuring Temperature at Distance Possible and Useful?

Climate alarmism of global warming claims to be supported by measurement of the energy balance of  Earth+atmosphere by instruments like pyrgeometers, bolometers and radiometers with an accuracy of at best 1-2 Watts/m2 compared to a total of around 240 W/m2 and a projected total imbalance of 4 W/m2 as "radiative forcing" from doubling of atmospheric CO2 corresponding to a warming of 1 K. 

The case for global warming may seem weak from these measurements, but nevertheless they serve to foster alarmism. 

To properly evaluate the measurements it is necessary to understand how these instruments are designed and how they operate. For a pyrgeometer or bolometer using a thermocouple as sensor, there are two fundamentally different views:

1. A thermocouple essentially measures incoming radiance from a source as a process variable. 
2. A thermocouple essentially measures a source temperature as a state variable.  

It is natural to make a comparison in terms of a bank account:

1. Difference between deposits and withdrawals as process variable.
2. Total savings as state variable.

We understand that total savings may be fairly stable, while deposits minus withdrawals can fluctuate quite a bit. The same for temperature vs radiance imbalance. 

What does then a thermocouple as sensor in fact measure? Radiance or temperature? 

1. There is a widely spread view that a thermocouple essentially measures radiance and so can be used to reliably measure both incoming and outgoing radiance for Earth+atmosphere and so determine imbalance, even if the accuracy is not better than 1-2 Watts/m2, and so detect global warming. Radiance is then measured through a calibration process confronting the sensor with sources of known temperature $T$ with radiance according to an assumed Planck-Stefan-Boltzmann Law of the form $\sigma T^4$.  

2. There is also a different view that a thermocouple essentially measures source temperature by essentially allowing the sensor to take on the source temperature by radiative equilibrium established optically at distance. In practice the radiative equilibrium source-sensor is only partially established by sensor cooling, but the principle of radiative equilibrium with equal temperature remains. 

Case 2 builds on a clear physical principle of radiative equilibrium in stable measurement of a state variable.

Case 1 is based on instrument calibration vs sources/blackbodies of known temperature $T$ assumed to give radiance input of $\sigma T^4$, while the true input is PSB in the form $\sigma (T^4-T_i^4)$, where $T_i$ is instrument base temperature which is not 0 in general. Case 1 is thus based on a calibration process using an incorrect PSB law inflating input radiance. Moreover the measurement concerns a process variable prone to instability. There are cryogenic sensors with very small $T_i$ and better precision. A proof of the correct PSB Law in classical terms without statistics is presented here and in this talk.

Case 1 is consensus and is used to support alarmism from measured radiance imbalance of Earth+atmosphere as if this is a fact. But the measurement precision barely can capture any imbalance from doubled CO2. Unfortunately many climate skeptics embrace the idea that a pyrgeometer measures massive incoming radiance (Downwelling/Upwelling/Outgoing Longwave Radiation) and so go along with a basic alarmist argument: The measured energy imbalance is the result of more CO2. 

A careful study shows that a thermocouple in fact measures source temperature as stable output, while derived radiance can be misleading because the calibration uses an incorrect PBS Law and is prone to instability. This means that measured energy imbalance can be questioned along with alarmism.

But the discussion is pretty much closed on 1 as the truth. Hopefully a new discussion can take place around the question: What does a thermocouple primarily measure and on what physical grounds? How can a thermometer acting at distance be constructed? Is an IR-camera such a thing?

AIRS Atmospheric Infrared Sounder Measuring Temperature

This is a follow up to the previous post on a debate with Will Happer concerning satellite measurement of Earth atmosphere: What is directly measured at distance: temperature or radiation? My view is that temperature is directly measured and so can be reliable, while radiation is computed using some complex software for radiative heat transfer and so is unreliable. It seems that Happer is not perfectly happy with such a clear statement but does not give a clear alternative. 

Let us see take a look at the most advanced system, which is the AIRS Atmospheric Infrared Sounder monitored by NASA presented as follows:

• AIRS is the first instrument ever to produce a three dimensional map of temperature and water vapour in the atmosphere directly measured from satellites: 

We understand AIRS directly measures temperature at distance and that this can be very useful information!

We recall that there are several instruments like bolometers, pyrgeometers and infrared cameras which read temperature at distance typically using a thermopile sensor taking on source temperature at one end by radiative equilibrium at distance (like a thermometer in contact) and instrument reference temperature at the other end thereby reporting a voltage depending on temperature difference, thus reporting source temperature. 

Why is then Happer speaking about measuring radiation? It is because global warming alarmism is based on an idea that the Earth absorbs more energy from the Sun than it emits to outer space as Outgoing Longwave Radiation OLR. Evidence is then presented as measured incoming and outgoing radiation, of size around 340 W/m2, from which a difference of less 1% is obtained and reported as alarming. That requires high precision measurement outgoing radiation from direct measurement and so it must be tempting to believe that this is what AIRS offers. But it does not.  

Happer is not a climate alarmist, but he seems to be stuck with the alarmist dream of measuring OLR to a very high precision. Strange.

PS We may compare reading temperature vs radiation with determining a persons bank net vs determining the power of the person. The bank net can be directly read which is not possible for power. 

Similarly, all lake side properties around the lake share the level of the lake, while their value is more difficult to decide.  

Spooky Action at Distance in Global Warming

This is a follow up of a discussion with prof Will Happer on Outgoing Longwave Radiation OLR from the Earth into outer space, which determines global warming or cooling, as concerns measurement of temperature and radiation by AIRS spectrometers in satellites looking down on the atmosphere with output (clear sky): 

We see a graph of radiative flux as function of frequency on a background of corresponding blackbody spectra at varying temperatures from 225 K at the top of the troposphere, over 255 K in the middle and 288 at the Earth surface. We see major radiation from H20 for lower frequencies at temperatures around 255 K,  from CO2 at 225 K and from the Earth surface at 288 K through the atmospheric window.

This graph is presented as the essential scientific basis of climate alarmism with the ditch in the spectrum giving CO2 a substantial role even if H20 and the window has major role. But the change in the ditch by doubling CO2 from preindustrial level is much smaller of size 1% of total incoming radiation from the Sun. 

In any case the measured spectrum of OLR by AIRS serves as key evidence of global warming by human CO2 emissions, but it requires an accuracy of less than 1%. 

Is this the case? We recall the spectrometer of AIRS is based on the bolometer which is an instrument measuring temperature in some frequency band at distance, from which radiation is computed using Modtran as software to solve Schwarzschild's equations of radiative transfer line by line. This is a complex computation involving coefficients of emissivity and absorptivity which are not precisely known. There are many posts on this topic under Schwarzschild and OLR and bolometer. Results are reported as radiative forcing from increasing CO2, typical of size 1% of total incoming. 

Thus temperature is directly measured while radiation is the result of a complex computation for which an accuracy of less than 1% is required. You have to be a believer in global warming to believe that this accuracy is met. In other words, the evidence of global warming supposedly being presented by the OLR spectrum is not convincing if you have the slightest inclination towards skepticism.

Back to Happer, who claims that it does not not matter what is directly measured, since there is a connection between temperature and radiation, and so one may as well view that AIRS measures radiation. Our discussion came to halt at this point. 

But to me it is clear that a bolometer (or pyrgeometer) is an instrument which directly measures temperature and if the instrument reports radiation, it is the result of a computation of unknown accuracy, which more precisely can be grossly misleading. In other words, reported temperature is reliable while reported radiation is not. 

The key observation is that CO2 radiation is measured to have temperature 225 K which means that it comes from the top of the atmosphere as the highest level where presence of CO2 is detected by the AIRS bolometer, with higher levels being transparent. 

The radiative forcing of 1% is thus based on a computation for which the accuracy is not known to be less than 1%. Your conclusion? 

The key question is then what can measured at distance, temperature or radiation? There are several instruments that can directly measure temperature at distance, such as infrared cameras, bolometers and pyrogeometers, all based on radiative equilibrium at distance rationalised as Computational Blackbody Radiation. This is an analog to measuring temperature by a thermometer in contact.  

But there are no instruments directly measuring radiation by some kind of photon capturing technique. Believing that this is possible represents belief in a some form of spooky action at distance. And you? And Happer?

PS In a letter to Max Born in 1947 Einstein said of the statistical approach to quantum mechanics, which he attributed to Born: I cannot seriously believe in it because the theory cannot be reconciled with the idea that physics should represent a reality in time and space, free from spooky action at a distance. This is  a different setting than that considered here: Reading temperature at distance is not spooky. Reading radiation is spooky action at distance.

KlimatUpplysningen 2: The Big DLR/Back Radiation Bluff

This is a reposting of an earlier post.

The Earth's energy budget is surveyed by

• pyrgeometers on ground measuring downwelling longwave radiation DLR (GEWEX)
• bolometers on satellites measuring outgoing longwave radiation OLR (ERBE and CERES)

where

• $DLR$ = heat flux from atmosphere to the Earth surface (in W/m2)
• $OLR$ = heat flux from atmosphere into outer space at 0 K (or 3 K)

operating according to the following algebraic formulas:

• $DLR  = V/K + \sigma T_i^4$ = $DLR$-Pyrgeometer Formula
• $OLR = E + \sigma T_i^4$ = $OLR$-Bolometer Formula 

where 

• $T_i$ is measured instrument temperature
• $V$ is voltage measured by pyrgeometer sensor and $K$ is a sensitivity coefficient
• $E$ is heat flux measured by a bolometer thermal link.

The Bolometer Formula is obtained from Stefan-Boltzmann's Law 

•  $E = \sigma (T_a^4 - T_i^4)$

where $\sigma = 5.67 \times 10^{-8}$ is Stefan-Boltzmann's constant, $T_a$ is the bolometric temperature obtained by calibrating the bolometer against a blackbody. Defining $OLR = \sigma T_a^4$ gives the Bolometer Formula with $OLR$ representing the heat flux from the atmosphere into outer space as stated. 

$OLR$ as reported by ERBE and CERES based on the $OLR$-Bolometer Formula is thus the heat flux from the Earth with atmosphere into outer space based on Stefan-Boltzmann's Law, and as such represents real physics: The Earth + atmosphere transforms shortwave heat energy received from the Sun into longwave heat energy which is returned to outer space as $OLR$.  This makes sense as true real physics.

We now turn to $DLR$, which we know by previous posts represents the BIG BLUFF of CO2 alarmism: The $DLR$-Pyrgeometer Formula seems to be an analog of the $OLR$-Bolometer Formula and the BIG BLUFF is now to argue that since the OLR-Bolometer Formula makes sense as an expression of Stefan-Boltzmann's Law, also the $DLR$-Pyrgeometer Formula makes sense. But this is not true!

The $DLR$-Pyrgeometer Formula is supposed to be an algebraic reformulation of  

• $\sigma (T_a^4 - T_i^4) = V/K$ with $DLR = \sigma T_a^4$,

where $\sigma (T_a^4 - T_i^4)$ is the heat flux between the atmosphere at temperature $T_a$ and the pyrgeometer at $T_i  > T_a$ according to Stefan-Boltzmann's Law, as measured by the (negative) voltage $V$. The BIG BLUFF is to give the algebraic reformulation a physical meaning with $DLR = \sigma T_a^4$ interpreted  as the heat flux from the atmosphere to the Earth surface. But this is not the physics:

• $\sigma T_a^4$ is heat flux from a blackbody into outer space at 0 K.
• $\sigma T_a^4$ is not heat flux from the atmosphere to the Earth surface because there is no such heat flux because $T_a <  T_i$.

We can see through the BIG BLUFF of CO2-alarmism with $DLR$ as heat flux from the atmosphere to the Earth surface with a warming effect:

$DLR$ is computed from a non-physical $DLR$-Pyrgeometer Formula which is deceptively similar to a physical $OLR$-Bolometer Formula, and the BIG BLUFF is to say that because $OLR$ is real so is $DLR$ and global warming. 

The BIG BLUFF of $DLR$ is

• cleverly constructed with a clever mixing of $OLR$ and $DLR$, 
• cleverly covered up in technical documents presenting the non-physical $DLR$-Pyrgeometer Formula as a version of the True Stefan-Boltzmann's Law, which expresses one-way heat flux from warm to cold,  
• hiding that the $DLR$-Pyrgeometer Formula represents a False Stefan-Boltzmann Law expressing two-way heat flux with in particular heat flux from a cold atmosphere to a warm Earth surface in violation with the 2nd Law of thermodynamics.      

Global warming alarmism is based on $DLR$ demonstrated by instrumental evidence as a scientific evidence of global warming by back radiation from "greenhouse gasses" including the trace gas CO2. But this is fabricated evidence without physics reality and so it is a BIG BLUFF.  It may be the BIGGEST SCIENCE BLUFF EVER, in the sense that it asks for diversion of massive resources into meaningless curbing of CO2 emissions with no doubt catastrophical consequences for large parts of the human population.  

It is not hard to see the bluff once you understand where to look and not get diverted away from what is really happening when the trick is performed.

PS Here is from the product specifikation of the Kipp and Zonen CG3 pyrgeometer:

• The CGR 3 is a pyrgeometer, designed for meteorological measurements of downward atmospheric long wave radiation. The CGR 3 provides a voltage that is proportional to the net radiation in the far infrared (FIR). By calculation, downward atmospheric long wave radiation is derived.

It could not be more clear: Net radiation is measured, DLR is derived.  The BLUFF! 

OLR Spectra Decoded as Fake!?

Consider the following outgoing long wave radiation OLR spectrum delivered by the Atmospheric Infrared Sounder AIRS flying on the Aqua satellite:

The graphs show the brightness temperature as function of wave number, with the brightness temperature the temperature of a blackbody with the same radiance at a given wave number as that recorded by the spectrometer (in principle bolometer) sensor, with in particular a zoom of the wave number interval 645 - 685 containing the main resonance at 667 of CO2.

We see a low brightness temperature of about 220 K and a peak at the main resonance at 667 of 250 K.  Both these brightness temperatures are lower than the temperature of 295 K in the atmospheric window between 800 and 1200, as if the sensor has recorded the presence of CO2 both at the tropopause (220 K) and in the middle of the troposphere (250 K).

We understand that a bolometer sensor measures radiance calibrated to blackbody radiance and thus cannot distinguish between low emissivity/high temperature and high emissivity/low temperature. This means that the assignment of brightness temperature is influenced by an unknown emissivity, which explains why the assigned brightness temperature is high at the main resonance 667 for which the emissivity is high, and low in the weak resonances surrounding the main resonance for which the emissivity is low. But it does not make sense that CO2 radiates from different temperatures for different frequencies, because all frequencies are assumed to have the same temperature.

The spectrum constructed is thus an artificial spectrum reflecting the sensitivity of the bolometer, which may be chosen so that resonances of CO2 are picked up before the continuous spectrum from the Earth surface, and then are assigned brightness temperatures according to radiance, as shown above. The weak resonances with low total emissivity of CO2 away from 667,  are then assigned a low brightness temperature (220 K) at full emissivity, as if all of the radiation from the Earth surface was blocked in the whole interval 600 - 800.

The OLR spectrum delivered by AIRS is thus an artificial spectrum constructed so as to hide that away from the main resonance 667, CO2 has small emissivity and thus cannot block all of the radiation from the Earth surface (even under doubled concentration from preindustrial level).

OLR spectra delivered by AIRS (and IRIS) are viewed as the key evidence of "heat trapping" or "radiation blocking" by atmospheric CO2. If these OLR spectra show to be fakes misrepresenting physics, the main scientific argument of CO2 alarmism evaporates.  So what does true science tell: fake or not fake?

PS To help discussion, recall the sparseness of the CO2 spectrum around 667 as pictured in the previous post.

CERES and Radiative Forcing

      The Earth's energy budget according to CERES showing unphysical "back radiation" of 340 W/m2
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An overview of the CERES project is given in CERES, a review: Past, present and Future (2011):

• The Clouds and Earth Radiant Energy System (CERES) project’s objectives are to measure the reflected solar radiance (shortwave) and Earth-emitted (longwave) radiances and from these measurements to compute the shortwave and longwave radiation fluxes at the top of the atmosphere (TOA) and the surface and radiation divergence within the atmosphere. The fluxes at TOA are to be retrieved to an accuracy of 2%. 
• The first objective of CERES is to measure OLR radiances to an accuracy of 1% and reflected solar radiances to 2%. The global mean OLR flux is approximately 240 W/m2, so the requirement is 2.4 W/m2 accuracy. Likewise the global mean reflected flux is 100 W/m2, thus the requirement for shortwave flux is 2 W/m2.

We compare the accuracy of 2-3 W/m2 with by IPCC supposed "radiative forcing of  CO2" of 1.8 W/m2 and "total anthropogenic radiative forcing" of 1.6 W/m2 during 1750-2005 and 3.7 W/m2 from doubled CO2. 

We conclude that the accuracy of CERES even at the lower level of 1% for OLR, would not be good enough to detect effects of "radiative forcing" by CO2. 

That the "radiative forcing" of doubled CO2 would be 3.7 W/m2 is a wild guess by IPCC without experimental support, which serves as the following cornerstone of CO2 alarmism:

• Without any feedbacks, a doubling of CO2 (which amounts to a forcing of 3.7 W/m2) would result in 1 °C global warming, which is easy to calculate and is undisputed. 

Here the "easy undisputed calculation" is dQ = 4 dT, where dQ is "radiative forcing" and dT corresponding global warming as a differentiated form of Stefan-Boltzmann's Law Q = sigma T^4. 

The number 3.7 or 4 W/m2 is so chosen by IPCC that the global warming would be 1 C, according to the "easy undisputed calculation", which is not too big to not be possible and not too small to be negligible. The basic argument of CO2 alarmism is that with feedback 1 C can become 3 C which is alarming. 

The whole idea of "radiative forcing" lacks sound physics basis since the forcing comes from the Sun and only from the Sun, and this is reflected by the fact that it cannot be discovered by instruments measuring physical phenomena, that is, it is fiction of a BIG BLUFF.

PS CERES is selling itself e.g. on a video telling us

• When you add greenhouse gasses such as CO2 and methane you change that radiation balance on the top of the atmosphere and you change the amount of outgoing radiation so that imbalance means more energy in the system...part of it goes into the ocean...and part of goes into actually warming the Earth...all of those things should give you a coherent picture of how things are changing as we warm the climate...

The purpose is obvious: Use CERES to show global warming by radiative forcing from CO2. The only trouble is that CERES shows nothing of this sort...all attempts to measure radiative forcing by CO2 seem to fail miserably...the scale of the BIG BLUFF with its organized governmental science support, is really impressive...  

CERES: No Global Warming Detected

In previous posts we have decoded the BIG BLUFF of CO2 alarmism based on fabricating evidence of a global warming effect of CO2 in large scale experimental projects such as ERBE followed by CERES designed to produce measurements of radiative fluxes. While ERBE focussed on outgoing long wave radiation OLR as one-way heat flux from the Earth + atmosphere into outer space at 3 K, which is physical heat flux, CERES has lifted the ambition to include two-way heat fluxes between different parts of the atmosphere and the Earth surface, which lack physical reality:

 

The objective of CERES is described as follows on Daily Press Febr 14 2012:

• Clouds and the Earth's Radiant System CERES is one of five earth science experiments aboard Suomi NPP, a $1.5 billion satellite NASA launched into space Oct. 28 2012 from Vandenberg Air Force Base in California.
• Managed at NASA Langley Research Center in Hampton, CERES measures the amount of sunlight that enters Earth and how much sunlight and thermal radiation is reflected back to space. The concept is known as Earth's energy budget.
• According to NASA, the sun annually provides the planet about 340 watts per square meter — roughly the energy radiated from six incandescent light bulbs. If the planet returned an equal amount of energy to space, temperatures would be constant, Loeb said.
• That is not occurring. Instead, roughly 0.8 watts per square meter stays on Earth.
• The energy is trapped by greenhouse gases, such as water vapor and carbon dioxide, that come from burning fossil fuels and other sources. Clouds also play a role; they reflect sunlight back into space and, depending on their height and thickness, prevent it from leaving the planet.
• The imbalance helps explain why global temperatures increased 1.4 degrees since last century and sea levels are rising, Loeb said.
• NASA uses computer models to summarize the images into daily and monthly reports that date back to 1985. That's when another Langley instrument, ERBE, or Earth Radiation Budget Experiment, began monitoring the planet.
• Four successive CERES instruments — the one launched in October is a fifth generation — followed, providing data used by, among others, the Intergovernmental Panel on Climate Change. 
• The panel, which shared a Nobel Peace Prize with former Vice President Al Gore, wrote what many view as the definitive report on climate change.

CERES has four main objectives:

1. For climate change analysis, provide a continuation of the ERBE record of radiative fluxes at the top of the atmosphere (TOA), analyzed using the same algorithms that produced the ERBE data.
2. Double the accuracy of estimates of radiative fluxes at TOA and the Earth's surface.
3. Provide the first long-term global estimates of the radiative fluxes within the Earth's atmosphere.
4. Provide cloud property estimates that are consistent with the radiative fluxes from surface to TOA.

CERES primary measured data are obtained as output:  

• scanning thermistor bolometer sensors which measure Earth-reflected and Earth- emitted filtered radiances in the broadband shortwave (0.3 μm - 5.0 μm), broadband total-wave (0.3 μm - >100 μm), and narrow-band water vapor window (8 μm-12 μm) spectral regions. 

We see that CERES is used to record radiative heat fluxes using sophisticated technology with the ambition to discover effects of global warming by CO2 as an radiative imbalance.  To the disappointment of the designers and users of CERES including IPCC Al Gore,  the instruments show next to nothing: An imbalance of 0.8 W/m2 out of 340 W/m2 is smaller than any thinkable measurement error. 

CERES (like LHC) thus discovers nothing, and what we can now expect is a new bigger project with more sensitive instruments with doubled accuracy with the hope of finding something which is not zero as evidence of global warming by CO2. 

This will not be cheap, but when you go to an expensive restaurant you expect to be offered something special, and so the high price and sophistication of the instrumentation can be seen as a guarantee that something will be discovered.  

BIG BLUFF: Pyrgeometer DLR as Bolometer OLR

The Earth's energy budget is surveyed by

• pyrgeometers on ground measuring downwelling longwave radiation DLR (GEWEX)
• bolometers on satellites measuring outgoing longwave radiation OLR (ERBE and CERES)

where

• DLR = heat flux from atmosphere to the Earth surface (in W/m2)
• OLR = heat flux from atmosphere into outer space at 0 K (or 3 K)

operating according to the following algebraic formulas:

• DLR  = V/K + sigma T_i^4 = DLR-Pyrgeometer Formula
• OLR = E + sigma T_i^4 = OLR-Bolometer Formula 

where 

• T_i is measured instrument temperature
• V is voltage measured by pyrgeometer sensor and K is a sensitivity coefficient
• E is heat flux measured by a bolometer thermal link.

The Bolometer Formula is obtained from Stefan-Boltzmann's Law 

•  E = sigma (T_a^4 - T_i^4)

where sigma = 5.67 x 10^-8 is Stefan-Boltzmann's constant, T_a is the bolometric temperature obtained by calibrating the bolometer against a blackbody. Defining OLR = sigma T_a^4 gives the Bolometer Formula with OLR representing the heat flux from the atmosphere into outer space as stated. 

OLR as reported by ERBE and CERES based on the OLR-Bolometer Formula is thus the heat flux from the Earth with atmosphere into outer space based on Stefan-Boltzmann's Law, and as such represents real physics: The Earth + atmosphere transforms shortwave heat energy received from the Sun into longwave heat energy which is returned to outer space as OLR.  This makes sense as true real physics.

We now turn to DLR, which we know by previous posts represents the BIG BLUFF of CO2 alarmism: The DLR-Pyrgeometer Formula seems to be an analog of the OLR-Bolometer Formula and the BIG BLUFF is now to argue that since the OLR-Bolometer Formula makes sense as an expression of Stefan-Boltzmann's Law, also the DLR-Pyrgeometer Formula makes sense. But this is not true!

The DLR-Pyrgeometer Formula is supposed to be an algebraic reformulation of  

• sigma (T_a^4 - T_i^4) = V/K with DLR = sigma T_a^4,

where sigma (T_a^4 - T_i^4) is the heat flux between the atmosphere at temperature T_a and the pyrgeometer at T_i  > T_a according to Stefan-Boltzmann's Law, as measured by the (negative) voltage V. The BIG BLUFF is to give the algebraic reformulation a physical meaning with DLR = sigma T_a^4 interpreted  as the heat flux from the atmosphere to the Earth surface. But this is not the physics:

• sigma T_a^4 is heat flux from a blackbody into outer space at 0 K.
• sigma T_a^4 is not heat flux from the atmosphere to the Earth surface because there is no such heat flux because T_a <  T_i.

We can see through the BIG BLUFF of CO2-alarmism with DLR as heat flux from the atmosphere to the Earth surface with a warming effect:

DLR is computed from a non-physical DLR-Pyrgeometer Formula which is deceptively similar to a physical OLR-Bolometer Formula, and the BIG BLUFF is to say that because OLR is real so is DLR and global warming. 

The BIG BLUFF of DLR is

• cleverly constructed with a clever mixing of OLR and DLR 
• cleverly covered up in technical documents presenting the non-physical DLR-Pyrgeometer Formula as a version of the True Stefan-Boltzmann's Law, which expresses one-way heat flux from warm to cold,  
• hiding that the DLR-Pyrgeometer Formula represents a False Stefan-Boltzmann Law expressing two-way heat flux with in particular heat flux from a cold atmosphere to a warm Earth surface in violation with the 2nd Law of thermodynamics.      

Global warming alarmism is based on DLR demonstrated by instrumental evidence as a scientific evidence of warming from "greenhouse gasses" including the trace gas CO2. But this is fabricated evidence without physics reality and so it is a BIG BLUFF. 

It is not hard to see the bluff once you understand where to look and not get diverted away from what is really happening when the trick is performed.

Making the Fiction of DLR Real

The existence of downwelling long wave radiation DLR from the atmosphere to the Earth surface is supposedly evidenced by radiometers such as pyrgeometers and bolometers and by direct estimation of the emissivity of the atmosphere by a formula depending on temperature and vapor pressure, in both cases with coefficients determined by calibration with some chosen reference.

A pyrgeometer determines DLR as

• DLR = U_emf/S + sigma x T^4 with T the temperature of the instrument,

where U_emf is a voltage recorded by the pyrgeometer detector and S is a sensitivity coefficient determined by calibration and sigma is the constant of Stefan-Boltmann's radiation law.

The first direct estimation by formula was given by Brunt (1932):

• DLR = (0.605 + 0.0048 x e^0.5)  sigma  T^4, 

with T the temperature  and e the vapor pressure 2m above the Earth surface and was followed by variations by Brutsaert (1975) and many others.

We see that in both cases DLR is determined from an ad hoc Ansatz of a certain form with certain coefficients to be determined by certain calibration. We understand that the Ansatz defines DLR ad hoc by formula and calibration, but the physical nature of DLR remains hidden since the Ansatz is ad hoc without physical basis. 

Confusion arises when DLR by its suggestive name is given the physical nature of a flux of energy from atmosphere to the Earth surface. The greenhouse effect GHE is based on this confusion which magically transforms the fiction of DLR into reality.

Note that both formulas include Stefan-Boltzmann laws only valid in a surrounding of 0 K, which is not the case, and thus are ad hoc False Stefan-Boltzmann laws without physical meaning.

Circular Reasoning of Climate Alarmism

The circular reasoning described in the previous post can be illustrated by the following example:

Suppose a government with a governmental institution GI has an agenda to redistribute the wealth in society and to this end presents a formula of the form:

• Input (salary) = Net Value Produced + Output (societal value) 

where 

• Output = sigma x T^4 
• T = level of testosterone
• sigma is a (positive) constant.

Suppose the government to convince people about the rationality of the redistribution, opens to private business to manufacture an instrument reporting Input (salary), which is based on the above formula with direct measurement of T through a cheap blood test and of course Net Value Produced, which is easy to measure. The government can then with support from GI referring to the instrument, motivate redistribution of wealth in an objective scientific way. Right?

Bolometer Fiction of OLR and DLR

Berkeley Bolometer tells us:

• A bolometer (or calorimeter) is a detector for radiation or particles. We use bolometers to detect light in the far-infrared and mm-waves. These detectors typically function as follows: An absorber of heat capacity C is thermally connected to a heat reservoir at temperature T0 by a weak thermal link G. The absorber sees the power of the incoming light Psignal and an electrical bias power Pbias and hence has a temperature T=T0+ (Psignal+Pbias)/G>T0. If the incoming power Psignal changes and Pbias stays constant the temperature T will change. A bolometer works by measuring this change of T with a thermometer which is directly attached.

A bolometer thus records absorbed net heat energy per unit time using as sensor a temperature dependent resistance. What is primarily recorded is thus temperature from which net absorbed power can be determined through the thermal link. If the bolometer also reports gross incoming radiance (DLR), this is based on a Planck formula specifying what is to be considered as gross outgoing radiation from the detector. But this formula represents a misconception of Planck's law as describing two-way gross heat transfer. The OLR and DLR reported by a bolometer is thus fiction, as is that reported by a pyrgeometer.