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Here is a better look at the difference between satellite and land based measured temperature trends. Both methods have their benefits and both are complicated. Its been noted already that some land based measurements could be in error. Satellite reading of the surface temperature is also not easy as all sort of things affect what gets radiated back to space where the satellite must measure (like clouds, humidity, etc). Section 2 in this link describes some of the satellite measurment problem https://www.sciencedirect.com/scienc...34425712004749
But.. I am assuming that for both land based and sat based temperatures are reasonably accurate. If you can prove this is not the case, please let us know (we already saw the fox news post many pages back). The thing I observed earlier is that if you are denying any climate change, you use satellite data. If you want to present a more shocking picture of climate change, you use ground based measurements.
I posted three examples of the planet temperarures vs time at the bottom of this text.
Im not sure anyone is denying that temperatures have increased, I think that shows up in all plots. One thing I did on all these plots is to add a straight line from about 1970 to present as in this region a straight line appears to fit. I wont argue about other lines possible fitting, the temperature rise just looks fairly linear to me in this region. FYI, the two land based plots show a bump in the 1940 to 1950 time frame and one web site indicated that this was due to something called the pacific decadal oscillation.
Regarding the straight line I added, I also found the slope of temperature change per year. You can see my little note on each plot. The slope of the first satellite based plot shows that if we continue along the line I drew in, we will increase the planets temperature by 1C in 87.5 years. Same thing was done for the two land based plots but they show the 1C rise in 53 and 57 years respectively.
According to this guy (who I am trusting more and more) the controversy is over how much change will occur in the future. http://clivebest.com/blog/?page_id=2949 and it depends on you model for positive or negitive feedback drivers.. which gets complicated and I would not claim to understand. Maybe the change will be more dramatic, maybe not.. but the trend to increasing temperaures sure looks real.
Check your middle graph posted above-- negative slope 1880-1910. Positive slope 1910 -1940. Negative slope 1940- 1970. Positive slope 1970 to 2000. 2000- present would be negative, except for 2 outlier hot yrs.---> 60 yr cycles of warming & cooling with a step function apparent so each 60 yr cycle is a little warmer than the last. (Same would be seen as the planet cooled from late 18th to late 19th century in 60 yr cycles with steps.)
The whole thing might be just due to the math involved__ the additive effects of multiple sin functions. We don't necessarily need "a reason" for the fluctuations. And maybe the cycles are fractal in nature, with other cycle lengths superimposed and apparent only on zooming in or zooming out.
To predict warming will necessarily continue may be like predicting October temps will be 115deg because Jan to Mar went from 32 to 57. Superstitious behavior results from mistakenly equating correlation with cause & effect.
"It's very hard to make predictions, especially about the future." --Yogi Berra
edited to add: I was just searching to find an appropriate, specific chart showing the almost exact correlation of solar activity with world temps, and I came across this: http://www.thelongview.com.au/docume...Kevin-Long.pdf Warning-- this appears to be a Tinfoil Hat Area-- but it was written in 2014 and his predictions seem to be correct so far...???
Last edited by guidoLaMoto; 08-17-2018 at 07:21 PM..
This looks like another web site where someone thinks that human produced greenhouse gas (primarily CO2) could not possibly be the driver for what is happening with global temperature rise.
So..like others have done, he is speculating on some other driver and that model says we should be heading into an ice age. I didnt read much past that.. but if we do head into an ice age in the next few years, I will look this web site up and read it in detail..
I am finding both water and carbon dioxide very interesting. Most of this first part is just text book stuff so I didnt bother with a reference..
Both of these molecules are the basis for life as plants somehow figured out how to use photosynthesis and convert H2O plus CO2 and make glucose - energy all life is based on..
These two molecules also share the somewhat unusual property of being dipoles. Most molecules have the negative and positive charges spatially on top of each other. A dipole on the other hand has a spacial separation of the net negative charge and the net positive charge. This creates an electric field around the molecule that increases its ability to capture incoming radiation. This is why such small concentrations of CO2 or water vapor have such a large influence on capturing IR radiation.
Interesting that these two molecules are both dipoles, are the basis for life and on top of that have a major influence on the planets climate..
In the climate system, there are drivers which directly act to change the climate and feedback mechanisms which react to changes in the climate and either can reduce or amplify what the driver caused.
The CO2 we have put into the atmosphere is a driver. We are adding CO2 into the atmosphere at an exponentially increasing rate by burning fossil fuel.
Water vapor is a feedback mechanism because its concentration increases with temperature. . So as the temperature rises because of some driver, water vapor increases, which in turn is more green house gas, which in turn is more trapped heat. However, water has this other property in that it condenses to a liquid when it cools from rising and turns into clouds. Clouds then block the sun reducing the solar input so act to cool things. So water can be both a positive or negative feedback driver. Positive feedback, we get accelerated global temperature change due to a driver. Negative feedback, we get less global temperature change from a driver. Im guessing but this positive or negative feedback and how much is part of the controversy between the two sides in this debate.
As I understand it, all IR radiation from the surface is initially absorbed within 1 Km height from the surface. That absorption then raises temperature. A molecule at some temperature re-radiates "black body" radiation. What goes upwards keeps getting absorbed and then re-radiated and this is referred to as scattering.
I think this web site does a good job of describing how CO2 ends up being responsible for what finally gets radiated out into space (and why its the important driver).
IR scatters repeatably upward through layers of the atmosphere until at between 5-9 km the air is so thin that the the atmosphere becomes transparent allowing CO2 emissions here to radiate out into space. At these levels there is little water vapour and CO2 dominates the energy loss. As CO2 concentrations increase so this level shifts to higher levels in the atmosphere since a critical density must be reached for the radiation to escape. These levels are colder (until we reach the troposphere) and IR loss is proportional to T**4 (Stefan Boltzman’s law). This means that slightly LESS energy is radiated to space than before and since the total energy must balance, the Earth warms up to radiate more heat to compensate. Don’t forget that there are windows in the IR spectrum with no absorption other than water vapour allows extra energy loss through evaporation and IR emission from clouds.
Splitting hairs, but the fact that co2 & h2o are dipoles has nothing to do with it. It's the fact that they're trivalent-- an inert gas (single atom) can only be made to translocate when it's hit by another molecule. A two atom molecule can be made to translocate or to increase rotation (like a spinning dumbbell), while a 3 or 4 atom molecule can do those but also can vibrate (angle between central atom & its satellites varies) in resonance with specific wavelengths.
Not all IR re-radiated from the surface is captured by atm-- the "atmospheric window" in those absorption spectrum graphs posted several times here earlier. H2o absorbs over a wide range of wavelengths in the IR band, while co2 has a much narrower absorption spectrum. Ch4 has a very narrow band and is present in minuscule concentrations, so, although it has a very high heat capacity on a molar basis, it still doesn't account for much energy absorption and can really be ignored.
"Scattering" is the mechanism by which GHGs exert their effect: when they absorb a photon, they re-radiate it instantaneously with a near (but not) zero delay. Those little delays add up. Half the re-radiated photons will proceed upward and be essentially unencumbered by the GHG on their way to space, but the other half will be re-radiated downward and will have to try to escape again by hitting another GHG molecule and hoping this time they are shot upward, so to speak. Cf- my pin ball machine analogy early in this thread.
Note that phenomena that show positive feedback are doomed to extinction (unlimited resonance). The fact that our Gaia planet has had a viable biosphere continuously for 4 billion yrs lends strong support to the notion that positive feedback systems do not have a very strong presence here.
Negative feedback systems, OTOH, can exist indefinitely if properly tuned dynamically. Clouds not only shield the planet's surface keeping temps down, but rain also dissipates heat from the atmosphere, dumping it ultimately into the oceans. The oceans then lose it again thru evaporation. And so it goes...
Note that phenomena that show positive feedback are doomed to extinction (unlimited resonance). The fact that our Gaia planet has had a viable biosphere continuously for 4 billion yrs lends strong support to the notion that positive feedback systems do not have a very strong presence here.
There may be limited temperature ranges where water gives positive feedback and then switches to a strong negative feedback.
What I could imagine (and this is just from my imagination) is the possibility of increased heating causing a positive feedback effect initially from more water vapor.
But at some point, this would create more clouds and the negative feedback mechanism of reduced solar input would kick in. If the "gain" of this negative feedback (warming creating more clouds) were high enough, it would stabilize the system possibly even with continued CO2 levels.
But.. it would still be serious global weirding and CO2 is what got us there.. You would have more clouds and more energy in the system. Easy to imagine storms being more bizarre and powerful than what we see now. Of course this would also reduce the solar input from what it is now (used by plants and in our own power generation with PV panels). Ok.. Im really in no position to speculate on something so complicated so that can be ignored, likely incorrect.
Regarding H2O and CO2 being dipoles and how this allows such small concentrations to have such a large effect on capturing IR emission from the planet, here is the link again to a tutorial that I think nicely explains this. Between 4 to 6 minutes talks about the Dipole effect.
Also, around 7 minutes is another description of why CO2 is responsible for finally emitting the IR energy back out into space and also why increasing the concentration reduces the amount of IR energy finally getting released out to space. It says the same as the link I gave previously. Increasing CO2 moves the final emission height out past where water would have condensed because of temperature. And that lower temperature results in reduced black body (or Boltzman’s law) emission resulting in additional energy being trapped at lower altitudes.
FYI, dismissing this for some conspiracy theory is just silly.
Another thing regarding the strong positive feedback of water vapor that I dont understand but makes me discount somewhat how strong this might be.
I didnt see any reference to this in the reading I have done but apparently water vapor doesnt extend high enough into the atmosphere to where the actual energy emission back out into space occurs from CO2. At some lower height, water vapor condenses because of temperature.
And if you are already trapping virtually all IR emission from the surface now, adding more water vapor would not seem to do anything except maybe add some delay to the scattering process which I would think would not matter. I would think it would still be CO2 at higher elevations that primarily governed IR release.
Once again.. speculation on my part from reading all the junk on the internet. Could be wrong.
The negative feedback from water vapor creating more cloud cover and reducing solar input is a lot easier to grasp...
FYI, a couple more links on the positive feedback due to more water vapor from increased temperature (which would be a bad thing).
I dont see any mention of positive feedback from water vapor in either of the links below. Makes me further think this effect is over blown in causing crazy future temperature increases. The Nasa site only mentions the negative feedback from more clouds.
[quote=waltcolorado;52846138]There may be limited temperature ranges where water gives positive feedback and then switches to a strong negative feedback.
What I could imagine (and this is just from my imagination) is the possibility of increased heating causing a positive feedback effect initially from more water vapor.
But at some point, this would create more clouds and the negative feedback mechanism of reduced solar input would kick in. If the "gain" of this negative feedback (warming creating more clouds) were high enough, it would stabilize the system possibly even with continued CO2 levels. quote]
Bingo!
[quote=waltcolorado;52846639]
And if you are already trapping virtually all IR emission from the surface now,...quote]
Incomplete thought-- we're not trapping all the IR, just all the IR above and below the atm window wavelengths.
Re: Boltzman's Law-- the bell shaped curve of black box radiation is shifted right or left by higher or lower temps of the radiating surface, but the amount of energy involved depends on the amount of incoming (ie- solar) energy. The out-going energy re-radiated by the surface has nothing to do with the air temp.
The ocean is for practical purposes an unlimited heat sink. The atm is about 5 miles thick and the ocean 5 mi deep (rough approx.). But water has a much higher heat capacity than air PLUS it's 800 x denser. As long as more clouds bring more rain, the air temp should remain in the Goldilocks zone.
As far as conspiracy goes-- there's absolutely no doubt the Liberals, for political gain & the "scientists," for funding/profit gains, have turned the GW thing into a major part of their agenda. Only time will tell if their science is correct or not.
Given the continued reluctance on the part of the so-called scientists to transparently release their data & computer programs, the e-mails confirming their biased collusion and their unjustified adjustment of data, one cannot but deduce their less than altruistic intentions. "Each point by itself is suggestive, but taken together, it is conclusive, Watson"-- Sherlock Holmes
nit picking myself although this is an important point in why CO2 traps more energy as the concentration moves the point where emission escape out into space higher and higher where the temperatures are lower..
Quote:
e: Boltzman's Law-- the bell shaped curve of black box radiation is shifted right or left by higher or lower temps of the radiating surface, but the amount of energy involved depends on the amount of incoming (ie- solar) energy. The out-going energy re-radiated by the surface has nothing to do with the air temp.
The radiated energy is proportional to the fourth power of temp.. Ie, very dependent on the temperature of the black body radiation source.
The Stefan–Boltzmann law describes the power radiated from a black body in terms of its temperature. Specifically, the Stefan–Boltzmann law states that the total energy radiated per unit surface area of a black body across all wavelengths per unit time {\displaystyle j^{\star }} j^{\star} (also known as the black-body radiant emittance) is directly proportional to the fourth power of the black body's thermodynamic temperature T:
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