Skip to comments.BIG NEWS Part V: Escaping heat. The Three pipes theory and the RATS multiplier
Posted on 06/18/2014 10:36:46 PM PDT by Ernest_at_the_Beach
David Evans has analyzed the black box system that is effectively Sunlight In, Temperature Out, and found a notch, a delay, and a low pass filter. The problem then is to work out their order and to fill in any other bits needed by the model. This post then, doesnt have big blockbuster moments (sorry), but these points need to be said.
Energy leaves Earth through a range of electromagnetic frequencies, but the bulk of them can be grouped into three main pipes. Radiation either comes directly off the land, oceans, ice and what-not on the ground, or it leaves via the atmosphere. Up in the air, carbon dioxide and water molecules do most of the work sending emissions of infra red to outer space. In the atmosphere, the radiating surface is a virtual concept and is effectively at different heights for different greenhouse gases. This is all non-controversial stuff, but a little difficult to see in your head. The three pipes are from the ground, from CO2 and from H2O.
The next problem is that people have measured surface temperature (which is fair enough), and this is what the solar model is aiming to model. But its not the same temperature as the temperature of the complex surface that is radiating to space. The two layers are tied together in a sense. If the ground surface warms, the radiating surface will warm but not by quite as much. That means any model needs to understand the relationship between changes in the temperature of the radiating layers and the temperature on the ground (and on the seven seas). Im sorry for anyone looking for a dog-fight here, but the multiplier in the Solar Model is boringly almost the same as the standard one used by mainstream climate scientists. We call it the RATS multiplier (Radiative Amplification To Surface) and its value is about 2.
Basically if it warms by 1 degree on the surface the RATS multiplier tells us it has warmed by about 0.5 degrees on the radiating surface. There were times when we thought it would be different, but it did indeed end up being about the same as the mainstream estimates. This is non-controversial stuff, but its important, and well be referring back to the RATS multiplier and more importantly to the Three Pipes. Jo
Guest post by Dr David Evans, 18 June 2014
This post is the second of the three posts in which we build the solar model. We already assembled a notch filter, a delay filter, and a low pass filter in cascade in part III, and in part IV we took a diversion to physically interpret the notch and the delay.
The output of the low pass filter is the record of changes in the effective temperature at which the Earth radiates to space, the radiating temperature. We then consider how the model will compute the changes in surface temperature from the changes in radiating temperature. It turns out to require just a very simple model of the atmosphere.
The output of the low pass filter is the temperature of the surface of the Earth that radiates directly to space. This radiating surface is a virtual surface, consisting of different physical surfaces at different electromagnetic frequencies of radiation.
At the electromagnetic frequencies that are absorbed and emitted by carbon dioxide, the surface of the Earth is at the one optical depth of the carbon dioxide, where an observer from space is looking through sufficient carbon dioxide that they cannot see below that layer, on average. The carbon dioxide emissions layer is about 8 km up in the atmosphere at the tropics. It is effectively where all emissions from Earth direct to space at the carbon dioxide frequencies occur, because, on average, emissions below this layer are absorbed by the carbon dioxide (space cannot see those emitting carbon dioxide molecules, so they cannot see space).
The electromagnetic frequencies of the atmospheric window are those that pass through the atmosphere unimpeded. At these frequencies, emissions direct to space come from the surface of the Earth.
At the emissions and absorption frequencies of water vapor (which is the main greenhouse gas), the emissions layer is on average about 10 km up in the atmosphere at the tropics.
There are also other emissions layers for other greenhouse gases, but in this simple analysis well ignore them because their effect is small.
Nearly all the heat lost by Earth goes through one of these three pipes to space, a pipe being a group of electromagnetic frequencies with the same emissions layer. The amount of energy flowing to space through each pipe increases with the temperature of its emission layer.
The radiating temperature of the Earth is the effective temperature of the radiating surface, and is simply the temperature as computed by the Stefan-Boltzmann equation for the emissions given off by the Earth. The temperature changes of the radiating surface are some sort of weighted average of the temperatures changes of the main three emissions layers.
The low pass filter computes the changes in the radiating temperature, that is, the temperature changes that determine how much heat is radiated to space. But the output of the solar model is not this temperature, but the temperature at the surface. So how can the model compute the changes in surface temperature from the changes in radiating temperature?
Changes in the temperature of the radiating surface are basically transmitted down through the atmosphere to the surface. At the frequencies of the atmospheric window the radiating surface is also the surface of the Earth so no transmission is required, but at the carbon dioxide and water vapor frequencies the transmission is literally down through the atmosphere.
As it happens, the solar radiation datasets we are using are all deseasonalizedbecause they measure the solar radiation at a constant distance from the Sun (of 1 AU, the average distance of the Earth from the Sun). Because our solar model is going to be driven by these datasets, it is oblivious to anything on a time scale of less than a year, such as seasons. The atmosphere acts and reacts relatively quicklyusually within days, always within weeks. So from the point of view of our solar model, the atmosphere acts instantly and therefore it can be modeled simply as a multiplier. So on the one hand our model is limited to timescales of a year or more, but on the other it sidesteps most of the complexity in the atmosphere.
The output of the low pass filter is a record of changes in the temperature of the radiating surface, which is around 255 K. The output of the solar model is a record of changes in the temperature at the surface of the Earth, which is around 288 K. The RATS (Radiative Amplification To Surface) multiplier connects them: the changes in (surface) temperature are equal to the changes in radiating temperature multiplied by the RATS multiplier, on the timescales of our model.
Later, fitting the notch-delay solar model to measured temperatures finds the RATS multiplier is most likely 2.1 (but definitely between 1 and 5). Mainstream climate science reckons the value is about two, so there is agreement there.
(The name RATS is coined here. The mainstream value is their value of the feedbacks for the sensitivity of climate to any exogenous forcings (note that this is after a Stefan-Boltzmann conversion from forcing to temperature, and that the value of the low pass filter for the long term (that is, at very low frequencies) is the value given by the Stefan Boltzmann equation). However the RATS multiplier does not apply to any reduction in outgoing heat in the CO2 pipe due to an increase in the CO2 concentration. We shall explain this in detail in a later post, but for now we are just focusing on building the solar model.)
In the next post we will finish off building the notch-delay solar model, as this solar model is called. [And then the fun will really begin says Jo]
Right now the atmosphere holds 350-390PPM of CO2.
I suggest we shoot to 1/2 that number and see what that yields. ..or how little certain yields will be...
If the Sun were to suddenly quit producing light and heat the Earth would freeze over within seven days from what I have read. What does that say about the Sun versus CO2?
Bookmarked the page for later reference.
Been arguing with regressives on facebook. Easy to do even being slightly intoxicated.
This is deep and needs a clear mind. Surely appreciate the links and am anxious to read when in a better state of mind.
I’m being contrarian and giving the other side time to take my bait so I can then draw a picture of what desertification looks like
Must have been a healthy amount of green plants to feed the critter,...estimated to stand 65 feet tall and 130 feet long and packed the weight of 14 elephants.
Going back to read all that I posted,....like tomorrow.,
I haven't seen too many publications about the CO2 problem lately, but a few years ago, I saw an article estimating that life on earth will go extinct in a few hundred million to a billion years because of the continuing decline of CO2 in the atmosphere. The mechanisms by which CO2 is sequestered in non-gaseous form are still not fully understood. I believe that I put a reference to this work in my profile.
Of course, atmospheric CO2 is the source of all carbon used by living things to increase their biomass. The only way to see a real decrease in CO2 will be to decrease the biomass. An analogy would be a sealed container of water. The airspace in the container at a given temperature will always have a certain level of humidity, which will remain as long as liquid water is in the container. The only way to decrease the humidity would be to remove the liquid water. In the case of carbon, the biomass is equivalent to the water, and the CO2 is equivalent to the vapor.
A big concern that I have right now is that these kooks will get their way and start to filter out and sequester atmospheric CO2. At some concentration, plants will no longer be able to filter CO2 from the air--the specific concentration will depend on species, so die-offs will occur in a species-specific manner. Since the decaying plants return CO2 to the atmosphere, the concentration of CO2 will not change much, but will hover around the limit of what that species can extract from the air. Decreased plant biomass also causes decreased everything else biomass. As the more susceptible species die off, there will be less and less biomass--still with little change on atmospheric CO2. By the time the change in CO2 concentration becomes significant, the biosphere will be gravely damaged.
I have seen commercials suggesting that limiting CO2 emissions will increase the quality of air for breathing. These commercials are factually wrong--CO2 content does not affect the ability to breathe. People regulate the amount of CO2 in their blood--which is far more concentrated than in the atmosphere--by changing the rate of breathing, and a change of a few tens of PPMs will not significantly affect that dynamic.
Sorry for being so wordy here. CO2 hysteria is a pet peeve of mine. It is clear that the hysteria is being drummed up so as to decrease our resistance to totalitarianism, and, unfortunately, too many people are falling for it.
I’m still hoping for an explanation that me and Rachel Jeantel can understand
I think more people are aware that it is a scam than ever before, but the collectivists keep pushing it no matter how much the public does not buy it.
How long has pMSNBC and CNN been on the air with super low audience numbers and still on the air promoting their lies?
Thanks again for these informative posts, and a new favorite site “for dissident thinkers”. It probably deserves a thread all it’s own, but be sure to check out Joanne’s free ebook “The Skeptics Handbook” - great stuff to totally dismay and piss off your friendly local climate scientist/liberal clown (sorry for the redundancy):
Thanks for the four pings. I’ll bookmark them so that when I have more time I can read through source material as well as Freeper response.
I'm going with the money model versus control. Declare CO2 a sin, thereby taxing everyone's use of oil (carbon)and make lots of money. the sheep are more willing to pay the tax than kill the moralists (Gaia followers).
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.