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.
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Don’t these people understand that when you ‘use one climate model and apply a sufficiently large forcing (e.g. 2xCO2) to obtain a climate change signal’, you only get to see what the modeller programmed? Presumtions in stead of real life measurements. The disgrace.
Who will finally unmask these climate clowns to the public at large?!
And how they can look at themselves in the mirror and not be ashamed or at least slightly embarassed, is beyond me. Scientists these days…
Will the next Copernicus please stand up?
I am not a scientist nor do I play one on TV but:
“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).”
Really?
Chuck L says:
“Really?”
I second that sentiment, they might as well of said: Another method, the one employed here, is to dispense with reality and inject one that we prefer.
Peer review … (sigh)
“Kahl et al., after analyzing 40 years of data and almost 30,000 measurements, determined that, in autumn and winter, the Arctic inversions have become significantly more stable and more common (Figure 2). The 41-year trend toward stronger inversions arrives from a combination of surface cooling and warming at about 5,000 feet. Inversions have strengthened by about 4.5�C, which represents almost half of the wintertime inversion strength common in the Arctic. So not only are there more inversions, but they’re twice as strong as they used to be.”
http://www.worldclimatereport.com/archive/previous_issues/vol2/v2n10/hot.htm
Characteristics of water-vapour inversions observed over the Arctic by Atmospheric Infrared Sounder (AIRS) and radiosondes:
“We found that the frequency of occurrence of water-vapour inversions is highest during winter and lowest during summer. The inversion strength is, however, higher during summer. The observed peaks in the median inversion-layer heights are higher during the winter half of the year, at around 850 hPa over most of the Arctic Ocean, Siberia and the Canadian Archipelago, while being around 925 hPa during most of the summer half of the year over the Arctic Ocean.”
https://airs.jpl.nasa.gov/news_archive/2012-02-17-Water_Vapor-Inversions-Over-Arctic/
I worked underground in a goldmine in Yellowknife, NWT (62.4 deg N) in 1980.
In January, going ‘below the collar’ at 8:00 AM and coming back to surface at 3:45 PM meant no daylight Monday to Friday. The sun was seen only on weekends and was a pale, cold light with no direct rays.
My daily observation at 3:45 PM +- 5 minutes was interesting in that darkness gradually gave way to more and more light and then higher and higher sun as the weeks progressed. The daily change in length of day is so dramatic at those latitudes that you could observe a daily change. It certainly demonstrated how ancient astronomers may have been struck by the progress of the heavens through a coincidence of daily habits and effects like the shadows of buildings.
I’ve been working with the reannalysis data set at http://www.esrl.noaa.gov/psd/cgi-bin/data/timeseries/timeseries1.pl. It has values for temperature and specific humidity as a function of pressure level. There is an inversion in the arctic especially in winter. The data set contains SST (skin surface temperature) and OLR (Outbound Longwave Radiation) at the TOA (Top of the Atmosphere). You can calculate the black body radiation at the surface from SST. Water vapor and CO2 will be radiating at the air temperature at the different pressure levels. Those molecules gain their energy from collisions with air molecules. They radiate both up and down and because they are radiating from the upper levels, more energy will be lost to space than transmitted to the surface. That which reaches the surface is reradiated through an atmosphere containing very little water vapor. My analysis of these data indicates that CO2 enhances OLR in the Arctic because it is radiating nearer to the TOA. Do your on analysis and come to your own conclusions.
Willis, I think this is related in terms of down-welling radiation. The article is from NOAA and was posted a few years back and would appear to show from observations that down-welling radiation was not very affective at warming things up.
Arctic summer time the puzzling summer of 2003
http://www.arctic.noaa.gov/essay_untersteiner2.html
“…The onset of melting usually occurs in early June, when the temperature reaches 0°C and the surface layer turns into a constant-temperature ice bath. In 2002, the temperature record shows an abrupt warming to about 0°C, on 24 May, suggesting an early arrival of the melt season. The warming event coincides with about a week of low short-wave (250 Wm-2) and high long-wave (300 Wm-2) down-welling radiation, which are typical of low overcast conditions. The web cam pictures of that period confirm the overcast. Both radiation and temperature values remained in the normal range for the rest of the summer, and freeze-up occurred as usual in the last week of August. Based on the early warming event in May, one may have expected an early onset of surface melting. Contrary to that expectation, the web cams show that it was not until late July 2002 when the snow cover took on a soggy appearance and isolated melt ponds appeared on the surface.
For the rest of the summer, the web cam pictures show only insignificant melt pond coverage until the deposition of new snow in late August. The pictures clearly show that snow from the preceding winter survived the entire summer, and we must assume that there was no, or very little, ice ablation at the surface.”
“…Soviet (Russian) records suggest a small probability of an all-summer snow cover. But none of the U.S. ice camps experienced a persistent summer snow. In light of recent news about global warming and polar amplification, the all-summer snow cover of 2002 is clearly unexpected.”
“Observations from the North Pole in summer 2003
Like the summer of 2002, the subsequent summer of 2003 also shows a somewhat belated (end of June) appearance of melt ponds but, by the first week of July, pond coverage was wide spread (Fig. 3).
Unexpectedly, toward the end of July, pond coverage decreased markedly (Fig. 4) while radiation and air temperatures were still at their normal summer values. A possible explanation is that the ice had become sufficiently porous for the melt water ponds to drain by percolation.
However, in mid-August the melt ponds re-appeared (see Fig. 5 in link), putting in question the hypothetical pond drainage by percolation.”
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.
RE: noaaprogrammer says:
February 3, 2014 at 10:37 pm
*** What is the source of this long wave radiation in the artic during the winter where the sun doesn’t shine for days on end? Open water/ground heat from the previous summer’s heating?***
Any object above absolute zero emits long wave radiation. The amount is proportional to the temperature or heat content. Therefore less long wave radiation is emitted during the winter, but it is still emitted. Open water will emit more than snow as it comes from the depths not just the surface. This is why there is an inversion in the polar areas during the winter season. Cloud will decrease the amount emitted and reflect or radiate it back down.
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).
Arctic Layer Cake?
That gives me the best excuse yet to remind UK readers “They always said Numbers aren’t a problem. You can count on Arctic Roll”
Dear Willis, It is good to see more data that the peer reviewed members of the 97% consensus are model scientist. Not the reality is in the observations set. Your analysis article is an enjoyable gem. One does wonder who were the peer’s who reviewed, maybe they should resign. But that is not the Nature of things. Keep up the good work.
Inverting the scientific method?
Bintanja et al. (2014) claim to have found “Arctic winter warming amplified by the thermal inversion and consequent low infrared cooling to space.”
From Willis’ analysis above, the “predominant Arctic wintertime temperature inversion” claimed by Bintanja et al., appears instead to be an inversion of the scientific method.
Nature journals’ peer review policies include:
(Emphasis added)
Bintanja et al’s claim that “the additional radiation that is generated by the warming of these layers is directed downwards” is definitely “novel”. Willis has also found it definitely “interesting”. Bintanja et al. appear to have taken the first step in Richard Feynman’s description of the scientific method – to “guess it”. However, they do not yet appear to have tested their model against observations, as done above by Willis.
The key question now for Nature Geoscience editors is to decide whether “model” results constitute “strong evidence”! Will Nature Geoscience maintain its “peer review” policies or will the editors and reviewers seek to restore the scientific method where evidence trumps models, as evidenced above by Eschenbach’s “amateur” science review?
Vince Causey says:
February 4, 2014 at 3:26 am
“You say that as if it is wrong, but it is not. There is no gravity, only bodies seeking to maintain their shortest proper time through space-time. A body moves through space-time so as its clock shows the shortest duration of time. Matter causes space-time to bend so that this trajectory will be curved through space-time. This looks to us as an acceleration through space.”
…the relativists had to claim that space is “curved” (into what dimension?) to explain that a massless particle/wave (the photon) is influenced by gravity. So they had to discard the description of gravity as a force and had to introduce “curvature”. “Curvature” must either be an intrinsic property of space or it must be a “bending” into some higher dimension, otherwise, into what direction would it bend? How many extra dimensions do we need? At least two if we want to describe the degrees of freedom necessary for arbitrary photon bending. So the spacetime continuum must be 6dimensional or higher if “curvature” is a real distortion of Euclidian geometry.
Peronsally I think something went wrong a while back and it’s all a bunch of baloney.
Robert Clemenzi says:
February 4, 2014 at 12:17 am
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.
Well, the inversion is the greenhouse effect – it does not “strengthen” it.
Without the polar downwelling radiation, the surface temperature would be about 45K. The only reason that it stays a moderate -70C (203K) is the downwelling radiation. This is very clear when you look at the radiosonde data.
***************************************
Can you do an energy balance to support you idea?
Figure 2. Downwelling surface longwave radiation as a percentage of the upwelling longwave surface radiation, June (upper panel) and December (lower panel).
****************************************
These figures show areas where the downwelling surface radiation as a percentage of the upwelling longwave surface radiation, June (upper panel) and December (lower panel) exceed 100%.
Why does that strike me as odd? How can you get more of something when the most you can get is 100% and that assumes 100% efficiency of the energy transfers….
Where is the energy coming from? It’s dark all day long in Arctic during the winter months.
Even I can vaguely recall black body basics from one of the upper division Physics courses I took 30 years ago. Apparently the authors either did not take such a course, or if they did, ignored it.
“So the spacetime continuum must be 6dimensional or higher if “curvature” is a real distortion of Euclidian geometry.”
Have you seen the series “Through the wormhole” (hosted by that fine scientist Morgan Freeman)? There have been so many physicists with pet theories involving parallel universes that exist in other dimensions that I would suspend disbelief. There was even a prediction of gravity from parallel universes affecting galaxy motion in our own – and such an observation has actually been made (gravity is supposed to move across dimensions as easily as a knife through butter).
Interesting stuff.
Willis, I second the notion that this should be submitted for publication as a letters comment. The Ceres data is freely available. That the authors got published on the basis of a single GCM is amazing. EVERY other such article I have read ( perhaps now over 50) involves discussing results of some modification to a GCM like superparameterization or regional downscaling. These always compared the modified model results to observation. That there is no observational comparison is just awful. Model runs by themselves should never be termed experiments, as they were here.
Very nice, fast rebuttal.
1055hPa air is warm hence -30c temps… sure.
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.’”
“2xC02” used here. Well, that also shows that their fudging with C02’s effects have an asymmetry in their radiative processes in the models. Now that they have separated the ‘model’s climate signal’ from the noise we can easily conclude that they have programmed the model incorrectly. The radiation must radiate in all directions equally. This clearly implies that the given model can and should not be used until this asymmetry is removed.
Robert Clemenzi says:
Without the polar downwelling radiation, the surface temperature would be about 45K. The only reason that it stays a moderate -70C (203K) is the downwelling radiation. This is very clear when you look at the radiosonde data.
<<<<<<<<<<<<<<<<<<<<<<<<<<<<<>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
45K?This has the aspect of unsupported theory. It is “very clear” that radiosonde data will not support your theoretical claims here.
You have also ignored the heat transported into the Arctic by the Gulf Stream, which is the primary source of heat to the Arctic in winter. Again, 45K? seems as a rather extravagant assertion, and quite bald.