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.

Man-Made Universality of Blackbody Radiation

Pierre-Marie Robitaille is one of few physicists still concerned with the physics of blackbody radiation supposed to be the first expression of modern physics as presented by Max Planck in 1900, as expressed in this article and this article and  this talk.

Robitaille points to the fact that a blackbody is a cavity/box $B$ with interior walls covered with carbon sooth or graphite. Experiments show that the spectrum of the radiation $B_r$ from a little hole of such a cavity only depends on frequency $\nu$ and temperature $T$ according to Planck's Law:

• $B_r=\gamma T\nu^2$   if $\nu <\frac{T}{h}$  and $B_r=0$ else,       (P)     

where $\gamma$ and $h$ are universal constants, and we refer to $\nu <\frac{T}{h}$ as high-frequency cut-off. 

Experiments show that putting any material body $\bar B$  inside the cavity will not change (P), which is seen as evidence that the spectrum of $\bar B$ is the same as that of $B$  independent of the nature of $\bar B$ as an expression of universality. 

This is questioned by Robitaille, but not by main-stream physicists. Robitaille insists that the spectrum depends on the nature of the body. 

Let us see what we can say from our analysis in Computational Blackbody Radiation. We there identify a perfect blackbody to have a spectrum given by (P) with $\gamma$ maximal and $h$ minimal, thus by maximal radiation and maximal cut-off. By experiment we determine that graphite is a good example of a perfect blackbody. By maximality a blackbody spectrum dominates all greybody spectra.

Let then a greybody $\bar B$ be characterised by different constants $\bar\gamma (\nu)=\epsilon (\nu)\gamma$ with $0<\epsilon (\nu) <1$ a coefficient of emissivity = absorptivity possibly depending on $\nu$, and $\bar h >h$. The radiation spectrum of $\bar B$ is given by 

• $\bar B_r=\epsilon (\nu)\gamma T\nu^2$  if $\nu <\frac{T}{\bar h}$ and $\bar B_r=0$ else.

This is not universality since $\epsilon (\nu)$ and $\bar h$ depend on the nature of $\bar B$. 

But let us now put $\bar B$ at temperature $\bar T$ inside the cavity $B$ with graphite walls acting as a blackbody and let $B$ take on the the same temperature (assuming $\bar B$ has much bigger heat capacity than $B$) with thus

• $\bar B_r=\epsilon (\nu)B_r$ for $\nu<\frac{\bar T}{\bar h}$ and $\bar B_r=0$ else.

We then measure the spectrum of the radiation from the hole, which is the blackbody spectrum of $B_r$:

• $B_r=\gamma\nu^2$ for $\nu<\frac{\bar T}{h}$ and $B_r=0$ else.

If we then insist  that this is the spectrum of $\bar B$, which it is not, we get a false impression of universality of radiation. By maximality with $h<\bar h$ the cavity spectrum $B_r$ dominates $\bar B_r$.

 

We conclude that the universality of blackbody radiation is a fiction reflecting a dream of physicists to capture existential essence in universal terms. It comes from using the cavity as a transformer of radiation from a greybody to a blackbody pretending that the strange procedure of putting objects into cavity with graphite walls to measure their spectrum, is not strange at all. 

We may compare with US claiming that the dollar $D$ represents a universal currency backing that by imposing an exchange rates $\epsilon <1$ for all other currencies $\bar D$, thus imposing the dollar as the universal currency for the the whole World forgetting that all currencies have different characteristics. This gives the FED a man-made maximal universally dominating role, which is now challenged... 

PS1 To meet criticism that painting the walls of the cavity with graphite may be seen as a rigging of the measurement of radiation through the hole, physicists recall that removing the graphite and letting the walls be covered with perfect reflectors, will give the same result, if only a piece of graphite is left inside the cavity. This shows to be true, but the piece of graphite is necessary and its effect can be understood from the maximality of blackbody radiation independent of object size. 

PS2 Recall radiation spectra of solid state is continuous while gasses have discrete spectra. Also recall that measuring spectra typically is done with instruments like bolometer or pyrgeometer, which effectively measure temperature from which radiation is computed according to some Planck law which may but usually does not represent  reality. Atmospheric radiation spectra play an important role in climate modelling, and it is important to take them with a grain of salt, since what is de facto measured is temperature with radiation being computed according to some convenient formula serving man-made climate alarmism.  

PS3 The Sun has a continuous spectrum and so probably consists of liquid metallic hydrogen. Main-stream physics tells that it has a gaseous plasma state.

Thermodynamics of Friction

Everything goes around in construction-deconstruction-construction...

In the previous post we considered viscosity in laminar and turbulent flow and friction between solid bodies as mechanisms for irreversible transformation of large scale kinetic motion/energy into small scale kinetic motion/energy in the form of heat energy, noting that the transformation cannot be reversed since the required very high precision cannot be realised, everything captured in a 2nd Law of Thermodynamics.  

Let us consider the generation of heat energy in friction when rubbing your hands or sliding an object over a floor or pulling the handbrakes of your bicycle. We understand that the heat energy is created from the work done by force times displacement (in the direction of the force), like pressing/pushing a sandpaper over the surface of a piece of wood to smoothen the surface by destroying its granular micro-structure. Work is thus done to destroy more or less ordered micro-structure and the work shows up as internal heat energy as unordered micro-scale kinetic energy. 

The key is here destruction of micro-structure into heat energy in a process which cannot be reversed since the required precision cannot me met.

Skin friction between a fluid and solid acts like friction between solids. 

Turbulent flow transforms large scale ordered kinetic energy into small-scale unordered kinetic energy as heat energy under the action of viscous forces. Laminar flow also generates heat energy from friction between layers of fluid of different velocity.

In all these cases heat energy is generated from destruction/mixing of order/structure in exothermic irreversible processes. This destruction is balanced by constructive processes like synchronisation of atomic oscillations into radiation and emergence of ordered structures like vortices in fluid flow and endothermic processes of unmixing/separation. 

We thus see exothermic processes of destruction followed by endothermic construction, which is not reversed deconstruction, with different time scales where deconstruction is fast and brutal without precision and construction is slow with precision. This is elaborated in The Clock and the Arrow in popular form. Take a look.

 

Norman Wildberger: Insights into Mathematics

Mathematician Norman Wildberger presents an educational program for a wide audience as Insights into Mathematics connecting to the principles I have followed in Body and Soul and Leibniz World of Math.

A basic concern of Wildberger is how to cope with real numbers underlying analysis or calculus, geometry, algebra and topology, since they appear to require working with aspects of infinities coming with difficulties, which have never been properly resolved, like computing with decimal expansions with infinitely many decimals and no last decimal to start a multiplication. Or the idea of an infinity of real numbers beyond countability.

I share the critique of Wildberger but I take a step further towards a resolution in terms of finite precision computation, which can be seen to be the view of an applied mathematician or engineer. In practice decimal expansions with a finite number of decimals are enough to represent the world and every representation can be supplied with a measure of quality as a certain number of decimals as a certain finite precision. This offers a foundation of mathematics without infinities in the spirit of Aristotle with infinities as never attained  potentials representing "modes of speaking" rather than effective realities. 

In particular the central concept of "continuum" takes the form of a computational mesh of certain mesh size or finite precision. With this view a "continuum" has no smallest scale yet is finite and there is a hierarchy of continua with variable mesh size.    

The difficulty of infinities comes from an idea of exact physical laws and exact solutions to mathematical equations like $x^2=2$ expressed in terms of symbols like $\sqrt{2}$ and $\pi$. But this can be asking for too much, even if it is tempting, and so lead to complications which have to be hidden under the rug creating confusion for students.

A more down-to-earth approach is then to give up exactness and be happy with finite precision not asking for infinities.  

How to Generate Heat Energy

We recall from a previous post:

• Heat energy can be generated from large scale kinetic energy by compression. 
• Kinetic energy can be generated from heat energy by expansion.

More precisely, we saw in the previous saw that heat energy at high temperature can generate useful mechanical work. Heat energy at high temperature can be created by nuclear/chemical reactions. 

Heat energy typically at lower temperatures also appears as losses from electrical currents subject to resistance, fluid motion subject to turbulent/laminar viscosity and friction between solid bodies. These losses appear as substantial, unavoidable and irreversible as expressions of a 2nd Law.

We have seen that heat energy $\sim T\nu^2$ of frequency $\nu$ carried by an atomic lattice of temperature $T$ subject to high-frequency cut-off $\nu <\frac{T}{h}$ expressing ordered synchronised atomic oscillation or kinetic motion, can be radiated. Here $h$ is a constant. 

We can view turbulent dissipation in fluid flow as a form of high-frequency forcing above present cut-off which cannot be reradiated and so is absorbed as internal energy in the form of unordered small scale kinetic energy. We can similarly view viscosity and friction as forms of high-frequency forcing supplying internal energy. 

The contribution to internal energy increases the temperature and so allows unordered small scale motion to be synchronised to higher frequency and then radiated.  

The key is thus that turbulent, viscous and frictional dissipation all represent high-frequency forcing above   present cut-off, which cannot be represented and reradiated and so shows up as internal energy as small scale kinetic energy. 

Rubbing hands is one way to transform large scale kinetic motion into small scale kinetic motion as heat energy. The brakes on your car work the same way. 

Exergy as Energy Quality

Kinetic energy, electrical energy, chemical and nuclear energy can all be converted fully into heat energy, while heat energy can only be partially converted back again. This is captured in the 2nd Law of Thermodynamics. We can thus say that heat energy is of lower quality compared with the other forms. More generally, the term exergy is used as a measure of quality of energy of fundamental importance for all forms of life and society as ability to do work.

We can make this more precise by recalling that the quality of heat energy comes to expression in radiative and conductive heat transfer from a body B1 of temperature $T_1$ to a neighbouring body B2 of lower  temperature $T_2<T_1$ in basic cases according to Stefan-Boltzmann's Law or Fourier's Law:

• $Q = (T_1^4-T_2^4)$            (SB)
• $Q = (T_1-T_2)$                    (F)

with $Q$ heat energy per time unit. Heat energy of higher temperature thus can be considered to have higher quality than heat energy of lower temperature, which of course also plays role in conversion of heat energy to other forms of energy. The maximal efficiency of a heat engine operating between $T_1$ and $T_2$ and transforming heat energy to mechanical work, is equal to $\frac{T_1-T_2}{T_1}$ displaying the higher quality of $T_1$.

Heat energy at high temperature is the major source for useful mechanical work supporting human civilisation, while heat energy at lower temperatures appears as a useless loss e g in the cooling of a gasoline engine.

But what is the real physics behind (SB) and (F)? This question was addressed in a previous post viewing (F) to be a special case of (SB) with the physics behind (SB) displayed in the analysis of Computational Blackbody Radiation. 

The essence of this analysis is a high-frequency cut-off $\frac{T}{h}$ allowing a body of temperature $T$ to only emit frequencies $\nu <\frac{T}{h}$, where $h$ is a constant. This allows a body B1 of temperature $T_1$ to transfer heat energy to a body B2 of lower temperature $T_2$ via frequencies $\frac{T_2}{h}<\nu <\frac{T_1}{h}$, which cannot be balanced by emission from B2.  

High frequency cut-off increasing linearly with temperature represents Wien's displacement law (W), giving improved exergy with increasing temperature.

The high-frequency cut-off can be seen as an expression of finite precision limiting the frequency being carried and emitted by an oscillating atomic lattice in coordinated motion, with frequencies above cut-off being carried internally as heat energy as uncoordinated motion. 

Higher temperature thus connects to higher quality heat energy or better exergy. The standard explanation of this basic fact is based on statistical mechanics, which is not physical mechanics. 

PS Radiative heat transfer without high-frequency cut-off would boil down to (F), while (SB) is what is observed, which gives support to (W).

Thermodynamics of War and Peace

Opposing ordered armies at the moment before turbulent destruction. 

The recent posts on 2nd law of thermodynamics describe a process where increasing spatial gradients eventually reach a level (from convection and opposing flow) where further increase is no longer possible because it would bring the process to brutal stop, and so some form of equilibration of spatial differences must set in where 

• each particle tends to take on the mean-value of neighbouring particles.   (M)

This is the process in turbulent fluid flow transforming ordered large scale kinetic energy into small scale disordered kinetic energy taking the form internal heat energy in a turbulent cascade of turbulent dissipation. Here (M) is necessary to avoid break-down into a stop. The flow or show must go on.

(M) is also the essence of the diffusion process of heat conduction seeking to decrease gradients, even if not absolutely necessary as in turbulent fluid flow.

It is natural to connect turbulence to the violent break-down of large scale ordred structures into rubble in a war necessarily resulting from escalation of opposing military forces in direct confrontation which at some level cannot be further escalated and so have to be dissipated in a war. 

It is then natural to connect the equilibration (M) in heat conduction to a geopolitical/parliamentary process in peace time, where each country/party takes on the mean value of neighbouring countries/parties keeping gradients small. 

While (M) is necessary in turbulence to let the flow go on, one may ask what the physics of (M) in the case of heat conduction, and find answer in this post. 

The mathematics is elaborated in: 

• Computational Turbulent Incompressible Flow
• Computational Thermodynamics
• Computational Blackbody Radiation

The geopolitical/parliamentary situation today evolves towards sharpened gradients, while politicians refuse to follow (M) and so there is a steady march towards break-down... 

Secret of Conductive and Radiative Heat Transfer

This is a continuation of the previous post on Heat Conduction in Solids as Radiative Heat Transfer with  clarifying analysis from Mathematical Physics of Blackbody Radiation and Computational Blackbody Radiation.

The key aspect of both conductive and radiative heat transfer is interaction in a coupled system of weakly damped oscillators of different frequencies tending to an equilibrium with all oscillators having the same temperature as the system temperature. The damping can be frictional (1st order time derivative) or radiative (3rd order time derivative) 

There are two main questions: (i) Why do different systems take on the same temperature? (ii) Why do oscillators with different frequencies in a system take on the same temperature?  

The answer is hidden in the interaction between incoming radiation, oscillator and outgoing radiation in a weakly radiatively damped oscillator analysed in detail in the above texts. The essence is that under near resonance between incoming frequency and oscillator frequency,  

• incoming radiation is balanced by outgoing radiation plus internal heating. 

This is a non-trivial basic fact reflecting that the forcing and oscillator are out-of-phase with a shift of half a period as a consequence of small radiative damping and near resonance. 

Two coupled oscillators thus interact with outgoing from one oscillator acting as incoming for the other and vice versa and so are led to take on the same temperature, which is then spread over the oscillators of a system and also over systems. 

The essential components in this equilibration process are thus

• weakly damped oscillators generating outgoing radiation and internal heating 
• out-of-phase balance between forcing and damping from near resonance
• high-frequency cut-off increasing with temperature from finite precision computation.  

This analysis connects to Planck's derivation of his law of radiation with statistics replaced by finite precision thus replacing non-physics by physics. 

Sverige Måste Vinna Kriget mot Ryssland?

Sverige besegrar Ryssland i slaget vid Narva 1701 under ledning av Karl XII.  

Idag skriver ett antal svenska ambassadörer och militärer på SvD Debatt:

• Regeringen bör skyndsamt hitta formerna för att mångfalt öka det militära biståndet till Ukraina. 
• Inför den ryska aggressionen befinner sig de västliga demokratierna som de befann sig inför Hitler.
• Kriget kommer inte att sluta så länge Putin sitter vid makten. 
• Enda sättet att avsluta kriget är alltså att Putin förlorar makten.
• Det kan ske om han lider ett så svidande nederlag...
• Putins avlägsnande är bara ett nödvändigt...kännbart ryskt nederlag i Ukraina.
• Ett sådant nederlag har den västliga demokratiska alliansen i sina händer. Hos den finns de vapen och de resurser med vilka Ukraina kan vända kriget och tillfoga Ryssland ett nederlag.
• Ukraina måste segra och Ryssland måste förlora.
• Vi vädjar till regeringen att tänka utanför den ärvda boxen – det gäller att skyndsamt hitta formerna för att mångfalt öka det militära biståndet till Ukraina.

Vi ser här att segern i Narva 1701 är i kärt minne i den "ärvda boxen", medan förlusten i Poltava 1711 och förlusten av Finland 1809 är bortglömda. Tanken är alltså att vi kan besegra Ryssland, som är den starkaste kärnvapenmakten i världen med nyvunnen konventionell militär styrka om mer än en million tränade soldater vida överlägsen den som västliga demokratier kan skrapa ihop, där Sverige kan bidra med kanske 3000 otränade pojkar och flickor, och därmed genomföra den erövring av Ryssland som Karl XII, Napoleon och Hitler misslyckades med.  

Speglar detta stämningarna hos det ledande skiktet av svenska politiker, ämbetsmän, militärer och företagare och svenska folket? Alla partier verkar vara inställda på krig även V och Mp. Fredsrörelsen har somnat. 

USA är på väg att dra sig ur, vilket ger Sverige en ledande roll som krigförande, naturligtvis tillsammans med Finland som är bra på krigföring i snö.

Påven ber Ukraina hissa vit flagg och gå till förhandlingsbordet där Putin väntar. Fortsatt krig gör bara saken värre för Ukraina och Väst. Ett mångfalt ökat militärt bistånd till Ukraina leder till WW3. 

Hur kan någon tro att Sverige kan vinna krig mot Ryssland idag? Eller tänker man att eftersom WW2 var bra för Sverige, så kan WW3 också vara det? I så fall bör man tänka en gång till.

En stark kärnvapenmakt kan inte besegras på hemmaplan. Det bästa resultat som kan uppnås är oavgjort som MAD Mutual Assured Destruction.

Lyssna på Pelle Neroth show med Mats Nilsson som förklarar saker o ting.