Guest Post by Willis Eschenbach
There’s a recent paper paywalled here, called Arctic winter warming amplified by the thermal inversion and consequent low infrared cooling to space. Fortunately, the Supplementary Online Information is available here, and it contains much valuable information. The paper claims that during the arctic winter, the atmospheric radiation doesn’t go out to space … instead it is directed downwards, increasing the surface warming.
Now I haven’t figured out yet how that works, radiation being “directed downwards”. But that’s what they say. From their Abstract:
We find that the surface inversion in fact intensifies Arctic amplification, because the ability of the Arctic wintertime clear-sky atmosphere to cool to space decreases with inversion strength. Specifically, we find that the cold layers close to the surface in Arctic winter, where most of the warming takes place, hardly contribute to the infrared radiation that goes out to space. Instead, the additional radiation that is generated by the warming of these layers is directed downwards, and thus amplifies the warming. We conclude that the predominant Arctic wintertime temperature inversion damps infrared cooling of the system, and thus constitutes a positive warming feedback.
Hmmm … so their basic claim is that the (poorly named) “greenhouse effect” is strengthened by the temperature inversion in the winter, that this slows the surface cooling, and that as a result the surface ends up warmer than it would otherwise be. A second claim is that the cause of additional Arctic winter downwelling radiation at the surface is a temperature inversion. The third claim is that this Arctic inversion is not unusual, but that there is a “predominate” winter temperature inversion in the Arctic.
Now, all of these claims can be investigated using the CERES satellite radiation dataset. To look at their first claim, I thought I’d follow the lead of the estimable Ramanathan and consider how much of the upwelling radiation from the surface is absorbed during the Arctic summer versus the Arctic winter. Ramanathan proposed the use of this atmospheric absorption of surface radiation as a measure of the strength of the greenhouse effect. Obviously, the more upwelling longwave that is absorbed by the atmosphere, the warmer the surface ends up. Figure 1 shows the strength of the greenhouse effect using Ramanathan’s measurement (absorbed radiation as a percentage of surface radiation) in June and in December.
Figure 1. Strength of the poorly-named “greenhouse effect”, as measured by the percentage of the surface upwelling longwave radiation (thermal infrared radiation) that is absorbed by the atmosphere. The situation is shown for the month of June (upper panel) and December (lower panel). Following Ramanathan, the absorbed radiation is calculated as the upwelling surface radiation minus the upwelling TOA radiation.
As you might imagine, and can see in Figure 1, the greenhouse effect is strongest where there is water. As a result, the effect is strongest in the tropics, and is stronger over the ocean than over the land. For the same reason, the greenhouse effect is weaker over the deserts and at the poles.
Now, their claim is that there is additional greenhouse warming in the Arctic in the wintertime compared to the summertime, slowing the radiative cooling of the surface. However, the CERES data disagrees, and indeed it shows the opposite. The CERES data says that at both poles, the greenhouse effect is stronger in the summertime, not weaker. This makes sense, because there is more water vapor in the air in the summer.
Note also that while there are areas of temperature inversions (shown in blue), and they do occur in a few areas in the Arctic winter(lower panel), they are not a general feature of the Arctic. On the other hand, large areas of the Antarctic do have a temperature inversion in winter (upper panel, blue).
So the CERES data doesn’t agree with the study regarding the slowed cooling in winter. The CERES data says the opposite, that cooling is easier in winter because less upwelling surface longwave is absorbed by the atmosphere. Nor does the Arctic temperature inversion seem to be as widespread or pervasive as the authors state.
Next, they claim increased downwelling longwave at the surface in the Arctic winter. To investigate this claim, Figure 2 shows the June and December downwelling longwave surface radiation, once again as a percentage of the upwelling longwave surface radiation.
Figure 2. Downwelling surface longwave radiation as a percentage of the upwelling longwave surface radiation, June (upper panel) and December (lower panel).
The main oddity in Figure 2 is that most places, most of the time, the downwelling radiation is about 86-88%, with not much difference summer to winter or place to place, particularly in the ocean. I wouldn’t have guessed that. Note that Figure 2 also reveals the widespread winter temperature inversion in the Antarctic winter (upper panel, red) indicated by downwelling longwave radiation exceeding upwelling surface radiation, and the lack of such a widespread inversion in the Arctic winter (lower panel, red).
More to the current point, we have a curiosity related to the authors’ claims about the Arctic. Note that in Antarctica in the wintertime (upper panel) there is a marked increase in the downwelling radiation as a percentage of the surface radiation compared to their summer (lower panel). The difference is large, 98% versus 64%. Presumably, this is the increased downwelling that they describe in their paper (although as expected the upwelling also increases).
But in the Arctic, where the paper claims this phenomenon of increased downwelling radiation is occurring, there is no difference between the downwelling surface longwave in the summer and the winter (88% in both cases).
So we do in fact find the phenomenon they point to of increasing downwelling radiation … but we don’t find it in the Arctic as they claim, we find it at the opposite pole.
Summary
1. Their claim, that there is “reduced cooling” in the arctic in wintertime that affects the surface temperature, is not supported by the CERES data. To the contrary, the CERES data shows the Arctic radiative cooling is much more rapid in the winter than the summer, because the atmosphere is absorbing much less radiation. Note that this is what we’d expect, due to the reduced amount of water vapor in winter.
2. Their claim, that the Arctic temperature inversion is widespread, is not supported by the CERES data. It shows general wintertime temperature inversion in the Antarctic, but not in the Arctic.
3. Their claim, that the Arctic downwelling longwave radiation increases in the winter, is not supported by the CERES data. Curiously, it is true in the Antarctic. In the Arctic, however, there is almost no difference between summer and winter.
Now, how did they get this so wrong? From their methods section (emphasis mine):
An often used method to increase the signal-to-noise (i.e. climate change- to-variability) ratio is to study multi-model output, such as those obtained in the CMIP3 initiative for ‘realistic’ forcing scenarios. The general idea then is to apply statistics on the multitude of independent members (individual models) to reduce the noise, and also to use intermodel differences to relate climate processes to feedbacks2.
Another method, the one employed here, is to use one climate model and apply a sufficiently large forcing (e.g. 2xCO2) to obtain a climate change signal that is much larger than the noise. The advantage of this approach is that dedicated experiments can be carried out, including changing certain model processes in order to link these to feedbacks (as is done in this study).
So … as usual, rather than mess with ugly observational data, it’s models all the way down. Actually it’s worse, it’s the output of one single solitary model all the way down. Or as a typical adulatory media report of the story says:
Pithan and co-author Thorsten Mauritsen tested air layering and many other Arctic climate feedback effects using sophisticated climate computer models.
Hey, as long they used a sophisticated climate model, and it is reportedly “based on true physics” in the best Hollywood tradition, what’s not to like?
Best to everyone,
w.
The Usual Request: If you disagree with something I say, please quote my exact words so we know what you are referring to. I can defend my own words. I cannot defend some vague claim like “Willis, your logic is wrong”. It may well be … but we’ll never find out unless you quote exactly the logical claims I made that you don’t like.
Data and Code: CERES calculated surface data (in R “save()” format) is here, 110Mbytes. and the CERES measured TOA data is here, 230 Mbytes. CERES Setup.R and CERES Functions.R are needed for the analysis. Finally, the code for this post is Arctic Amplification.R
Also, it’s worth noting that while the CERES top-of-atmosphere data is from measurements, the surface data is calculated from the TOA data using energy balance considerations. Obviously, a global set of observational surface radiation data would be wonderful … but since we haven’t got that, the CERES data is the best we have.
The Pompous Git says:
February 3, 2014 at 10:50 pm
Most historians believe that Galileo never actually conducted the Tower of Pisa experiment described by his disciple Viviani. Those who do think he did imagine his using a larger & smaller ball of the same material (presumably iron), not a wooden ball of the same size & shape as an iron one, or that he used a larger iron cannon ball & smaller but denser lead musket ball. But maybe there is a reference to wood that escaped me.
I hope a physicist will correct me if wrong, but IMO a wooden ball would not initially fall faster & be overtaken by a heavier metal ball. I have not conducted the experiment myself, but suppose that air resistance would affect the less dense object from the start, so that it would not initially fall more rapidly.
GG knew about air resistance, so that a denser object of the same shape would hit the ground before the less dense one. He wrote however that the slight difference in this result did not show Aristotle to be correct, since the ancient philosopher predicted a much greater difference.
Better to see how the temperature rise in the upper part zone on the ozone a temperature increase level of 250 hPa-jet stream. This means further inhibition of the jet stream. Science, science, and the winter will be long.
http://www.cpc.ncep.noaa.gov/products/stratosphere/strat-trop/gif_files/time_pres_TEMP_MEAN_JFM_NH_2014.gif
Well see how it looks.
http://www.cpc.ncep.noaa.gov/products/intraseasonal/z200anim.gif
John Tillman says:
February 4, 2014 at 8:13 am
We believe that Galileo’s “real world experiment” was actually held – wonders of modern “models” physics was actually “experimental” in some areas! – but that he used a long inclined board to slow the heavy and light spheres and allow the difference in times to be seen. (No stopwatches, no light-activated timers below the very short tower of Pisa.)
Slowed by the inclined plane, any two balls of equal size but vastly different weights would not be greatly affected by air resistance.
M Seward says
Can you moderate my name to “M Seward” in the previous post! Sad isn’t it?
I’ll have some of whatever he’s having….
RE: DirkH says:
February 4, 2014 at 7:05 am
Gerald Machnee says:
February 4, 2014 at 7:02 am
“Any object above absolute zero emits long wave radiation. The amount is proportional to the temperature or heat content. ”
Not proprtional, but rising with the 4th power of absolute temperature (Stefan-Boltzmann law).
OK. I do not remember the amount. I should have said ‘Increases”.
Willis Eschenbach says:
February 4, 2014 at 12:11 am
ren says:
February 4, 2014 at 1:10 am
Multiply theory? What the heck does that mean? Is that like
3 * E = M C 2 / (1/3)
In any case, I was answering a direct question, so what’s your point?
w.
Robert Clemenzi says:
February 4, 2014 at 12:17 am
Thanks, Robert. However, since …
• The greenhouse effect exists around the planet (see Fig. 1).
and …
• Most of the planet doesn’t experience widespread temperature inversions on any regular basis.
and …
• Temperature inversions do happen in Antarctica, where the greenhouse effect is not that strong (see Fig. 1)
I’d have to say your good ship “Theory” just ran aground on a reef of ugly facts … the greenhouse effect is many things, but claiming that “the [temperature] inversion is the greenhouse effect” is simply untrue.
w.
“1. Their claim, that there is “reduced cooling” in the arctic in wintertime that affects the surface temperature, is not supported by the CERES data. To the contrary, the CERES data shows the Arctic radiative cooling is much more rapid in the winter than the summer, because the atmosphere is absorbing much less radiation. Note that this is what we’d expect, due to the reduced amount of water vapor in winter.”
The data here tends to suggest that there is reduced cooling in winter: http://ocean.dmi.dk/arctic/meant80n.uk.php
For most years since 2005 the winter temperatures above 80 degs north have been above the 1954-2014 average.
Any thoughts on this Willis?
Box of Rocks says:
February 4, 2014 at 7:21 am
This occurs when there is a temperature inversion, and a colder surface is overlain by warmer air. Since the radiation is proportional to T4, you end up with more downwelling radiation than upwelling radiation.
w.
Re Galileo’s experiment
According to Galileo, he performed the experiment with the wooden and iron balls as described. While he did not record the location, we are certain he didn’t perform it at Pisa since the height from which his assistant dropped the balls was considerably higher than the tower — IIRC about 100 m higher. [Bloody Windows 7 search function cannot find any html documents containing the word “galileo” today!]
It is true that Aristotle was quantitatively incorrect, but he was qualitatively correct. The mathematisation of physics had to await Galileo. I find it a bit OTT to fault Aristotle for not realising something that took another 2,000 years to discover! It’s worth noting that Aristotle was a great observer; i.e. he said we should trust our sense perceptions. His teacher, Plato, claimed the reverse. One should not trust one’s senses when investigating the world. You can discover all you need to know by introspection. To my mind, GCMs are advanced introspection devices.
For those more curious, See:
Physical experiment: Galileo’s “falling bodies” experiment re-created at Pisa
Thought experiment: “Spuntar lo scoglio piu` duro: did Galileo ever think the most beautiful thought experiment in the history of science? Paolo Palmieri
JBJ says:
February 4, 2014 at 9:45 am
Thanks, JBL. My understanding is that their claim is that the “reduced cooling” means reduced cooling with respect to the summertime, not w.r.t. the 1954-2014 average. I didn’t see anywhere that they talked about global warming or cooling.
Finally, what you are looking at there is reanalysis data. It’s uncertain at present, but it gets worse rapidly as you go back to 1954.
w.
“The third claim is that this Arctic inversion is not unusual, but that there is a “predominate” winter temperature inversion in the Arctic.”
True.
Pilots flying in the Arctic in the 1930’s noticed this. They have gauge which shows the outside air temperature and they noticed an increase in temperature with altitude.
The inversion starts to break down with the return of the sun.
“Their claim, that the Arctic temperature inversion is widespread, is not supported by the CERES data. It shows general wintertime temperature inversion in the Antarctic, but not in the Arctic”.
It is supported by observation and by Upper Air Sounding Plots as Ulric Lyons says:
http://weather.uwyo.edu/upperair/sounding.html
Willis Eschenbach Sorry, my English is lame. Sorry. I guess I will not be spoken, because You misunderstand me.
I wanted to say that my observations confirm this.
Willis Eschenbach says:
February 4, 2014 at 9:55 am
Box of Rocks says:
February 4, 2014 at 7:21 am
From Wikipedia..
“…Under certain conditions, the normal vertical temperature gradient is inverted such that the air is colder near the surface of the Earth. This can occur when, for example, a warmer, less-dense air mass moves over a cooler, denser air mass. This type of inversion occurs in the vicinity of warm fronts, and also in areas of oceanic upwelling such as along the California coast in the United States. With sufficient humidity in the cooler layer, fog is typically present below the inversion cap. An inversion is also produced whenever radiation from the surface of the earth exceeds the amount of radiation received from the sun, which commonly occurs at night, or during the winter when the angle of the sun is very low in the sky. This effect is virtually confined to land regions as the ocean retains heat far longer. In the polar regions during winter, inversions are nearly always present over land….”
So, still makes no sense.
If I understand the inversion starts in the Arctic when the surface radiates more energy that what it receives so an inversion is created. And with the inversion more radiation flows back the surface and hence the inversion is degraded over time and eliminates itself or becomes cyclic in nature right?
The figure is wrong because some extra energy was transported to the poles and was added to the ‘normal’ downwelling radiation.
Again one can only get back out of a system what was put into the system, If the earth is radiating X amount of energy, at best X amount of energy can be returned. The reality is that at most – only .35X can be returned since the downwelling radiation is going in all directions.
David L. Hagen said @ur momisugly February 4, 2014 at 10:11 am
Interesting 🙂
Another good job. Thanks again.
You have already written the letter (what’s posted here), why not submit it to Nature Geoscience?
Using a % won’t get you very far I wouldn’t think… Why not express everything in W/m^2 so you can see the seasonal differences in absolute terms?
warofthewolds says:
February 4, 2014 at 7:00 am
Chuck L says . . .” really?”
If I read you right, please finish your story about the arrogant leaf – it struck a chord with me. If I read you wrong . . . well, I guess this won’t make any sense.
Not sure what you meant but what I meant was that this is based on computer models deliberately tweaked to produce what would appear to be, a predestined desired outcome.
saltspringson says:
I think this study is proof of Lindzen’s recent observation – “I’ve asked very frequently at universities: ‘Of the brightest people you know, how many people were studying climate […or meteorology or oceanography…]?’ And the answer is usually ‘No one.’”
===
Indeed, a lot of what gets published as climate “science” is on a par with sociology. At the most econometrics. There are few that could hold thier own in a hard science context.
I hate, and that is not too strong a word to use, these simulated experiments because they are so unlike the genuine article. And in this case the ambiguity of a paragraph, like the following one that Willis quotes, is so hard to interpret.
I presume that “additional radiation” refers to the greenhouse effect, but I don’t know. The authors use “these layers” and Willis refers to the “surface”. When are the two the same? I frankly don’t know, but if the Arctic surface is not radiating strongly, then how does one develop the “inversion” that is central to the thesis here? The surface is the only thing black enough to provide LW radiation to the clear sky. At the sort of water vapor and CO2 contents of the air at minus 40F and lower, it takes many tens of thousands of feet of air to come even close to resembling a black body (emissivity=1). Thus the idea that “these layers”, presumably of air, predominate in the radiative transfer in any direct, up or down, seems not sensible to me.
My understanding of this issue, and someone please correct me if I am completely off base, is that the Arctic is the site of generally subsiding air throughout its winter. This subsiding air has work done on it via compression, warms as a result, and then transfers heat to the surface where it is radiated away. This is the source of the inversion. Though I am not familiar with the Ceres data, Willis’ claim that the winter Arctic surface must radiate strongly, in some normalized sense like fraction of input heat rate, makes perfect sense.
The authors make two claims that seem correct, being that “these layers” do not radiate strongly, and that heat input to the surface (not by radiation but by other means) keeps the surfae warmer than it would be otherwise; but I fail to see why these are of great significance and how their conclusion follows.
“””””……johnmarshall says:
February 4, 2014 at 3:05 am
Sounds like a rehash of that crap GHG theory. Radiation from the Arctic will not be the average 240W/m2 but far lower. The maximum radiation to space is from tropical regions because the temperature is higher. The rate of heat loss is proportional to the 4th power of the temperature difference…….””””””
NOT SO !!; each body (assumed black) radiates per S-B law proportional to the fourth power of ITS TEMPERATURE, regardless, or irregardless, as the case may be, of the Temperature of any other body
So maybe it is (Tsource)^4 – (Tsink)^4; but certainly NOT (Tsource-Tsink)^4.
Am I the only person on this planet, who is bothered by the fact that no such object as a black body, that absorbs 100.000% of ALL EM radiant energy, from zero frequency to infinite frequency, sans the two end points; or zero to infinite wavelength, with the same exclusions, CAN EXIST.
No body that absorbs 100.000% of ANY single wavelength, even can exist either. No physical material has the same permittivity, and permeability as free space, and can thus propagate energy across the boundary, with 0.000 reflectance; even at any single frequency, let alone all. Such a BB, must also have infinite thermal conductivity, so that the body is isothermal; all at the same Temperature no matter where incoming EM radiation strikes it.
Nor do cavity radiators or absorbers buy you a reprieve. The standard BB cavity absorber, requires the contained radiation to be in thermal equilibrium with the walls, which must have 100.000% reflectance, and 0.000% absorption, and also must have 0.000 thermal conductivity, or else “heat” energy will be lost through the walls, cooling the wall Temperature. No material can have zero absorbtance either.
So “Black Bodies” don’t exist; so how come we have a theory of how they work ??
Another method, the one employed here, is to use one climate model and apply a sufficiently large forcing (e.g. 2xCO2) to obtain a climate change signal that is much larger than the noise. The advantage of this approach is that dedicated experiments can be carried out, including changing certain model processes in order to link these to feedbacks (as is done in this study).
They made virtual changes to parameters of an unverified/noncertified computational model. These are not experiments, dedicated or otherwise! The results are environmental fiction. In fact, I propose we demand just such an Evironmental Fiction section be added to all libraries and bookstores, where studies such as this (and contributions from Al Gore and Michael Mann) can find an appropriate venue.
I don’t know how this could pass peers review……… unless……..could it be? Oh my….
http://jasonseilerillustration.blogspot.com/2011/07/study-of-piers-morgan.html
I have a very informative Infra-Red Handbook, full of information, including a complete bibliography of all the peered at papers, that sourced the information.
In chapter 3; The Earth as Seen from Space.” there are a set of eight graph panels each containing curves for three different zenith angles; 0, 60, 85 degrees.
Four of the panels are sunlit over North America, and four are not sunlit over North America.
And the four pairs, are for 10-20 deg. N Lat., 30-40 deg. N Lat., 50-60 deg. N Lat., and 70-80 deg. N Lat.
The four not sunlit are in Winter, and the four sunlit are in summer. Wunnerful; finally some real information.
Well NO, not exactly. These are NOT “The Earth as Seen from Space.” They are actually; “What my Terraflop X-Box Thinks it Can See.
No they don’t claim they can see Siberia from the front door. These are just somebody’s idea of what you would see from space over North America, in Summer and Winter, from 10-20, 30-40, 50-60, and 70-80 deg. N Lat., sunlit or non sunlit.
The peered at paper is from H. Rose, et al in “The Handbook of Albedo and Thermal Earthshine” from the Environmental research Institute of Michigan, (ERIM) in 1973. who also published the handbook I have on IR.
You can always tell when these graphs are computer made up, because the spectral dips at wavelengths due to specific GHGs, like CO2 or O3, tend to have a flat bottom, with a little pip right in the center of it, as though it folds about the center point.
For these graphs given, the bottom of the CO2 dips, is pretty much independent of zenith angle, but the 9.6 micron dip for ozone, is very strongly dependent on zenith angle. Well this is what you would expect for a high very thin ozone layer, where an oblique view of the layer can be much thicker than the normal thickness. (due to vertical fluctuations of the layer). The Ozone dip is also very narrow, compared to the CO2, possibly because the ozone is high at low air density, and very cold, so both density and Temperature broadening are smaller than at the surface. Now this would affect individual lines, but possibly not the whole band, whose width may be based on molecule factors I’m not in on.
Strangely, not one of the eight panels shows any signs of spectral dips due to H2O.
So how hard can it be to point a telescope down at the earth at an angle (off normal) and record, what the earth actually does look like from space, instead of from a computer game screen ??
So does anyone actually have credible spectra taken from the ground looking up, and from space looking down ? With and without clouds.