What stratospheric hotspot?

There’s no predicted hotspot in the upper troposphere, and cooling of the stratosphere is now the new indicator. New paper finds “greenhouse cooling” of the stratosphere over past 52 years

image

On the left is the data collected by millions of weather balloons.xiv On the right is what the climate models say was happening.xv The theory (as per the climate models) is incompatible with the observations. In both diagrams the horizontal axis shows latitude, and the right vertical axis shows height in kilometers. Image from Dr. David Evans

A new paper published in Atmospheric Chemistry and Physics finds the stratosphere of the Northern Hemisphere cooled over the past 52 years due to the increase of greenhouse gases. The paper suggests that stratospheric cooling is a “more suitable” signal of anthropogenic global warming than trying to find a mid-troposphere hot spot (which was previously considered to be the definitive “fingerprint” of man-made global warming, but still has not been found despite millions of weather balloon and satellite observations over the past 60 years):

According to the authors, 

A major open question that still remains to be answered is whether the stratosphere can be considered as a more suitable region than the troposphere to detect anthropogenic climate change signals and what can be learned from the long-term stratospheric temperature trends. Indeed, the signal-to-noise ratio in the stratosphere is, radiatively speaking, more sensitive to anthropogenic GHG forcing and less disturbed by the natural variability of water vapour and clouds when compared to the troposphere. This is because (a) the dependence of the equilibrium temperature of the stratosphere on CO2 is larger than that on tropospheric temperature, (b) the equilibrium temperature of the stratosphere depends less upon tropospheric water vapour variability and (c) the influence of cloudiness upon equilibrium temperature is more pronounced in the troposphere than in the stratosphere where

the influence decreases with height (Manabe and Weatherald,

1967). Furthermore, anthropogenic aerosols are mainly

spread within the lower troposphere (He et al., 2008), and

presumably have little effect on stratospheric temperatures.

Another open question is whether the lower stratosphere

has been cooling in the time since a reasonable global network

became available, i.e. after the International Geophysical

Year (IGY) of 1957–1958. Such a long-lasting cooling

from the 1960s until today would need to be explained.

To what extent are the cooling trends in the lower stratosphere

related to human-induced climate change? Has the

cooling been accelerating, for instance at high latitudes in

winter/spring due to ozone depletion? Has it been interrupted

by major volcanic eruptions and El Niño events (Zerefos et

al., 1992) or large climatological anomalies.

This study addresses those questions and presents a new

look at observed temperature trends over the Northern Hemisphere from the troposphere up to the lower stratosphere in a search for an early warning signal of global warming, i.e. a

cooling in the lower stratosphere relative to the warming in

the lower atmosphere.

However, even the most ardent fans of anthropogenic global warming theory don’t agree on why an increase of “heat trapping” greenhouse gases would have the opposite effects of causing the stratosphere to cool and the troposphere to warm.

Further, many warmists claim any source of warming including solar activity, cloud changes, ocean oscillations, etc. would cause a mid-troposphere “hot spot” and overlying cooling of the stratosphere, and would not necessarily be a signal or “fingerprint” of anthropogenic global warming.

The authors also find from 1958-1979 the lower troposphere either slightly cooled or remained unchanged, followed by significant warming 1980-2010:

From 1958 until 1979, a non-significant trend (0.06 ± 0.06 °C decade−1 for NCEP) and slightly cooling trends (−0.12 ± 0.06 °C decade−1 for RICH) are found in the lower troposphere. The second period from 1980 to the end of the records shows significant warming (0.25 ± 0.05 °C decade−1 for both NCEP and RICH). Above the tropopause a significant cooling trend is clearly seen in the lower stratosphere both in the pre-1980 period (−0.58 ± 0.17 °C decade−1 for NCEP, −0.30 ± 0.16 °C decade−1 for RICH and −0.48 ± 0.20 °C decade−1 for FU-Berlin) and the post-1980 period (−0.79 ± 0.18 °C decade−1 for NCEP, −0.66 ± 0.16 °C decade−1 for RICH and −0.82 ± 0.19 °C decade−1 for FU-Berlin).

Thus, although it appears the stratosphere may be cooling, and this could be due to increased greenhouse gases, there is still no evidence of a mid-troposphere “hot spot” predicted by climate models. The slight cooling to no change of lower tropospheric temperatures from 1958-1979 found by this paper also don’t support AGW theory since CO2 levels rose ~7% during that period.

The paper:

Atmos. Chem. Phys., 14, 7705-7720, 2014

www.atmos-chem-phys.net/14/7705/2014/

doi:10.5194/acp-14-7705-2014

Evidence for an earlier greenhouse cooling effect in the stratosphere before 1980 over the Northern Hemisphere

C. S. Zerefos, K. Tourpali, P. Zanis, K. Eleftheratos, C. Repapis, A. Goodman, D. Wuebbles, I. S. A. Isaksen, and J. Luterbacher

Abstract

This study provides a new look at the observed and calculated long-term temperature changes from the lower troposphere to the lower stratosphere since 1958 over the Northern Hemisphere. The data sets include the NCEP/NCAR reanalysis, the Free University of Berlin (FU-Berlin) and the RICH radiosonde data sets as well as historical simulations with the CESM1-WACCM global model participating in CMIP5. The analysis is mainly based on monthly layer mean temperatures derived from geopotential height thicknesses in order to take advantage of the use of the independent FU-Berlin stratospheric data set of geopotential height data since 1957. This approach was followed to extend the records for the investigation of the stratospheric temperature trends to the earliest possible time. After removing the natural variability [it is impossible fully distinguish natural variability from anthropogenic] with an autoregressive multiple regression model our analysis shows that the period 1958–2011 can be divided into two distinct sub-periods of long-term temperature variability and trends: before and after 1980. By calculating trends for the summer time to reduce interannual variability, the two periods are as follows. From 1958 until 1979, a non-significant trend (0.06 ± 0.06 °C decade−1 for NCEP) and slightly cooling trends (−0.12 ± 0.06 °C decade−1 for RICH) are found in the lower troposphere. The second period from 1980 to the end of the records shows significant warming (0.25 ± 0.05 °C decade−1for both NCEP and RICH). Above the tropopause a significant cooling trend is clearly seen in the lower stratosphere both in the pre-1980 period (−0.58 ± 0.17 °C decade−1 for NCEP, −0.30 ± 0.16 °C decade−1 for RICH and −0.48 ± 0.20 °C decade−1 for FU-Berlin) and the post-1980 period (−0.79 ± 0.18 °C decade−1 for NCEP, −0.66 ± 0.16 °C decade−1 for RICH and −0.82 ± 0.19 °C decade−1 for FU-Berlin). The cooling in the lower stratosphere persists throughout the year from the tropics up to 60° N. At polar latitudes competing dynamical and radiative processes reduce the statistical significance of these trends. Model results are in line with reanalysis and the observations, indicating a persistent cooling (−0.33 °C decade−1) in the lower stratosphere during summer before and after 1980; a feature that is also seen throughout the year. However, the lower stratosphere CESM1-WACCM modelled trends are generally lower than reanalysis and the observations. The contrasting effects of ozone depletion at polar latitudes in winter/spring and the anticipated strengthening of the Brewer–Dobson circulation from man-made global warming at polar latitudes are discussed. Our results provide additional evidence for an early greenhouse cooling signal in the lower stratosphere before 1980, which appears well in advance relative to the tropospheric [assumed] greenhouse warming signal. The suitability of early warning signals in the stratosphere relative to the troposphere is supported by the fact that the stratosphere is less sensitive to changes due to cloudiness, humidity and man-made aerosols. Our analysis also indicates that the relative contribution of the lower stratosphere versus the upper troposphere low-frequency variability is important for understanding the added value of the long-term tropopause variability related to human-induced global warming.

(this post via the HockeySchtick)


 

RELATED:

About that missing hot spot in the upper troposphere

Stalking the Rogue Hotspot

The Skeptics Case

 

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So, is it “warming causes cooling”
or “cooling causes warming”?
I’m so confused!

catweazle666

I don’t suppose the stratosphere could possibly be cooling because we’re around half way through the negative – ie cooling – phase of the ~60 year cycle that appears to be linked to oceanic oscillations, could it?
No, of course not, that would be far too obvious.

Claude Harvey

So once again, “cooling proves warming”. Can we now take all this one step further and say, “the models being wrong proves they were right”?

Justthinkin

Wow.Just wow.In my next life I’m coming back as a weatherman or politician.The only 2 professions where you can lie through your teeth 100% of the time,and still keep your job.

Roy

The “missing heat” is obviously not in the deep oceans. It is hiding in the mid-troposphere hot spot. That explains why thermometers give the illusion that there has been no global warming for the past 17 years.

Resourceguy

Does this mean the climate minions will be going back around to all the grade schools to apologize for misinformation in prior guest presentations with scare tactics?

Jordan

Hot spot or hot potato.
This paper will probably raise heckles. Look forward to a rushed-out response, as we have seen before. Maybe a make-over for “too noisy to conclude” method of hypothesis reversal.
As far as I’m concerned, the researchers might as well add that no fairies were spotted at the bottom of the garden in the same period. It really doesn’t matter if the fairy observations are noisy.

Nor could it be cooling because of two successive feeble solar cycles.

hunter

More post hoc excuse making. Predicting is much easier after the fact.
And of course keep your metrics limited to [things that] are inaccessible and for which the reporting can be easily controlled.
Not to mention raising an alarm off of something that actually impacts no one.
There is an interesting point hidden away in the report: Could it be that, as the gas law implies, the atmosphere adjusts to changes in energy levels in a very direct and self regulating manner?

Latitude

[it is impossible fully distinguish natural variability from anthropogenic]….
…but we can tell you within a 1/100th of a degree

The other Ren

Are we talking “observed” temperatures or normalized “observed” temperatures? You never know these days.
Also the Boeing 707 started the jet age about 50 years ago and you just wonder how the contrails and jet exhaust constantly being emitted at 9-12 km above the surface just might come into play since most of the weather balloons are released primarily where these plane fly.

joelobryan

maybe the cooling stratosphere signal data haven’t been tampered with yet? Just an oversight that GISS and NCDC will now have to include this data set in their AGW Truthing algorithms.

Gary (Arkansas)

Jordan says:
August 4, 2014 at 8:18 am
“This paper will probably raise heckles.”
This caused my grammar scourge to kick in. I was just about to correct Jordan but then realized “heckles” is the better term. Bravo. 😉

Joseph Bastardi

Now this has my attention! I have always said that the sign of global warming would be a cooling upper stratosphere.. as that would imply expansion below that level and warming! So this is an interesting paper to me and one that I think can gain traction. However it still does not answer the question: is it man made? And we are going to get our answer soon enough given the change in the PDO and AMO would imply tropospheric cooling and warming above again ( reversal of the cooling) . But we have to let the OBJECTIVE TEST PLAY OUT! It is about half way done now.. Satellite temps from the warmer ocean era, but we must let the cooling cycle play out. either way draconian drivel from the people pushing this really have nothing to do with the actual science. But this is a paper I have always wondered was not done by the side pushing it.. perhaps because the people that buy into are not motivated by such things
My only criticism is that if they are going to say this.. and have me say, yes you have a point!, then they must say, so do you, we have to watch the next 20-30 years. After all most weather is below to above.. the source regions are where there is the most heat and that is the tropical ocean
Why do I think I am the one that is saying you have a point and they will simply say
fuggedabout it

Mark Hladik

“We do precision guesswork … … …
… … … …
… … …
… … …
… using high technology!”

Alan McIntire

I can see how a reduction in O3 would decrease stratospheric temperatures, but I don’t see how increased greenhouse gases would do so.
From your HockeySchtick Link:
“Cooling due to the greenhouse effect
The second effect is more complicated. Greenhouse gases (CO2, O3, CFC) absorb infra-red radiation from the surface of the Earth and trap the heat in the troposphere. If this absorption is really strong, the greenhouse gas blocks most of the outgoing infra-red radiation close to the Earth’s surface. This means that only a small amount of outgoing infra-red radiation reaches carbon dioxide in the upper troposphere and the lower stratosphere. ”
This explanation as given doesn’t make much sense. If greenhouse gas absorption is really strong, it may INITIALLY block most of the outgoing infra-red radiation, but ultimately the gas will have to re-radiate as much as it blocks.

Jimbo

A major open question that still remains to be answered is whether the stratosphere can be considered as a more suitable region than the troposphere to detect anthropogenic climate change signals and what can be learned from the long-term stratospheric temperature trends.

First we had “the oceans ate my global warming” ie forget surface temps, let’s go into the deep sea, then global warming stopped. Now this. It is a predictable fingerprint of moving goalposts.

Jimbo

Not “then”, I meant when.

First we had “the oceans ate my global warming” ie forget surface temps, let’s go into the deep sea, when global warming stopped. Now this. It is a predictable fingerprint of moving goalposts.

It had to be caused by AGW or the paper would never have been published.

The sun heats the stratosphere directly. The solar output peaked in the 50s, so we should expect a cooling trend.

GregL

Question: If I remember the physics correctly from the radiative transfer classes I took (I am not a radiation physics person), is it not true that if you have a gas that is a preferred absorber/emitter of radiation at certain wavelengths whose concentration decreases with height, then there will be some altitude/layer at which an increased overall concentration of it will cause a net increase of radiation out to space? If I remember correctly, this is because the decreasing concentration of it past a certain level means that more absorbed/re-emitted radiation in the preferred wavelengths will then be able to escape preferentially towards space as it will encounter fewer of the absorbing molecules in that direction. In other words, a heat trapping gas with decreasing concentration with height would be expected to have some higher level in the atmosphere with a net cooling effect owing to the vertical concentration gradient. Anyway, is this correct? This is what I remember from radiative transfer equations courses I took 20 years ago, but I may be remembering it incorrectly.

Evan Jones

JohnWho says:
August 4, 2014 at 7:51 am (Edit)

Stratospheric cooling will occur if heat is being retained in the troposphere. Actually, I agree with the direction of the study. I think we have had a mild but steady thumb under the scale since 1950, and that we see flat trend during negative PDO and double-warming during positive PDO. (Plus some other extraneous factors. Sootsolarlandusewhatever.)

crabalocker

Claude Harvey says:
August 4, 2014 at 8:03 am
So once again, “cooling proves warming”. Can we now take all this one step further and say, “the models being wrong proves they were right”?
—————————————————————————————————————–
lol….I love this comment!

LeeHarvey

@ Claude Harvey –
We can only assert that the models are right because they are wrong after we have passed the law to find out what’s in it.

ren

What is the mechanism of cooling of the stratosphere? Changing the chemical reactions in the stratosphere occurs only under the influence of ionizing solar and cosmic radiation. Any change in temperature above the tropopause takes place under the influence of ionization and occurs mainly in the ozone layer.
http://www.cpc.ncep.noaa.gov/products/stratosphere/strat-trop/gif_files/time_pres_TEMP_MEAN_ALL_NH_2013.gif

Sweet Old Bob

Move the goalposts? What? You KNOW those round things are a safety feature! Think of the children!
You can’t possibly believe WE would EVER use that hitch to change the game!
That would be beneath us! We are not crooks! You are just too uneducated to understand! It’s for your own good!
Money? What money? Look! Over there! Squirrel!
(Need I add sarc?)

Climate Weenie

Wait, what?
The title asks ‘What stratospheric hotspot?’
There never has been a case for a ‘stratospheric hotspot’.
The tropical upper tropospheric hotspot is modeled ( and failed ).
But the RF of the stratosphere has always indicated cooling and yes, this is indeed
consistent with CO2 forcing.
Here is my plot:
http://climatewatcher.webs.com/HotSpot_SatelliteEra.png
The strat cooling and lack of TUT Hot spot are evident.

BarryW

Though it’s hard to see on the charts it looks like the Stratospheric cooling stopped in the 21st century about the time the warming stopped in the lower layers.

ren

One note of CO2 is a gas gravitationally heavy, heavier than air. Just as the amount of water vapor decreases rapidly in the upper troposphere.

A Scott

Anthony – might be useful if one of our excellent “folks who know” would provide a simple discussion/primer on how the stratosphere and troposphere interact and react … in particular educate folks that the stratosphere typically reacts opposite to the troposphere … if the troposhere is warming, the stratosphere is cooling & vice versa …

Gary Pearse

As often is the case, I notice something a bit tangential to the main theme of a post. Thinking about the lack of a mid-tropospheric hot spot that was calculated from climate theory, it seems to me that this failure of the theory is a good starting point for overhauling the theory. What in their models and calculations defines this hotspot? Presumably it is convection of moist air from the hot equatorial sea surface rising to the mid-Trop. If this is the case (please correct me if it is not), we should have a hotspot there EVEN WITH NO global warming. Indeed, the immediate question is why do we not have such a hot spot as a matter of course.
This warm moist air certainly must rise to (or through) there almost continuously during the daytime. So what happened to the heat? Well it must have gone somewhere else. For it not to even have had a short retention time there, it must have continued up and out the top of the atmosphere as LWIR or spread surprisingly quickly N and S to modify the temperature of the mid troposphere over the higher latitudes, or both.
Looking at the atmospheric heat cross-section in the top figure, there is a surprisingly uniform heating from the equator towards the poles, so the quick spread away from the equator is certainly an important factor. Remarkably, if the illustration is typical of the actual atmospheric cross-section, there is a substantial depression in the temp profile directly over the equator and even a cool spot where the hot spot should be. The “dimple”, my friends, logically, must be the result of LWIR radiating out of the top of the atmosphere. One (not me!) could calculate the volume of this annular depression over the equator and its temperature differences and obtain a figure for the LWIR over the equator (and compare it to the satellite measurements of such radiation). The lower “cool spot” must be an enthalpy change in the atmospheric water – forming clouds, maybe even ice and heat from this joins the net upwelling of LWIR.

Dale Monceaux

It is quite amazing that there are literaly hundreds of hypotheses (guesses) as to why there has been an interruption in global warming, yet there can only be one reason for global warming to exist in the first place.

I knew all of this
[that GHG’s cause cooling rather than warming, on average]
http://blogs.24.com/henryp/2011/08/11/the-greenhouse-effect-and-the-principle-of-re-radiation-11-aug-2011/
note the date on that
hence,
GHG is the wrong term chosen….

@Joe Bastardi
I don’t think any cooling or warming is man made or that any AGW or AGC is significant.
It seems there is [absolutely] no room for it in my last equation?>
http://blogs.24.com/henryp/files/2013/02/henryspooltableNEWc.pdf

ren

Since the temperature in the area of the ozone depends on ozone, examine the amount of oxygen in the stratosphere. Maybe there is less oxygen?

Climate Weenie

Barry,
“Though it’s hard to see on the charts it looks like the Stratospheric cooling stopped in the 21st century about the time the warming stopped in the lower layers.”
I looked at that.
The RAOB data is a lot nosier ( as we would expect with it’s smaller coverage and reduced resolution ) but the MSU data sets seem to indicate the continued cooling.
http://climatewatcher.webs.com/HotSpot_Pause.png
The effect of stratospheric cooling is to slightly reduce RF at the tropopause.

Matthew R Marler

John Who: So, is it “warming causes cooling”
or “cooling causes warming”?

CO2 causes surface and troposphere warming (that’s the theory), but causes stratospheric cooling.
CO2 mixes throughout the atmosphere at approximately equal ppm (but obviously lower density at lower pressures [higher altitudes]). The increase in the CO2 total mass in the stratosphere results in an increase in the net radiation in the stratosphere, which is a net spaceward radiation. You can see the energy flow displayed in the famous Trenberth and Fasullo and Stephens et al energy flow diagrams, though it was a theoretical prediction that increased CO2 in the stratosphere would produce stratospheric cooling. The case is complicated, as explained by the authors in the Introduction: The primary radiative forcing mechanisms responsible for
global temperature changes in the stratosphere since 1979 have been increases in well-mixed greenhouse gas (GHG) concentrations, increases in stratospheric water vapour, the decrease in stratospheric ozone primarily related to chlorine and bromine from various halocarbons, the effects of aerosols from explosive volcanic eruptions, and the effects of solar activity changes (e.g. Shine et al., 2003; Ramaswamy et al., 2006; WMO, 2007; IPCC, 2007, 2013). The effects
of volcanic eruptions, variations in solar radiation, and other sources of natural variability, including the wave-driven quasi-biennial oscillation (QBO) in ozone, can be accounted for through the use of indices in time series trend analyses (Tiao et al., 1990; Staehelin et al., 2001; Reinsel et al.,2005; Fioletov, 2009). However, the attribution of past lower stratosphere temperature trends is complicated by the effects of the increases and levelling off of ozone-depleting substances (ODSs) and the inter-annual to decadal variability of the Brewer–Dobson (BD) circulation.

Surface and tropospheric warming have not been observed for the last 15 years or so, but this study confirms the hypothesized cooling of the stratosphere.
This result, even if confirmed by others for other parts of the stratosphere and even if it continues into the future, does not “rescue” the theory of catastrophic effects of greenhouse gas induced warming. That theory depends on surface and lower troposphere and upper ocean warming (where the catastrophes are hypothesized to take place and where the catastrophic warming is hypothesized to occur), and there hasn’t been observable warming in those locations for as long as Christopher Monckton of Brenchley says there hasn’t been (readers know this appraisal depends, as he has written, on which data sets are accorded the greatest weight.)
Note also that whereas the ocean warming is damped by the great mass of the ocean, the stratospheric cooling is observed because of the lower mass of the stratosphere, as acknowledged by the authors. The result is compatible with the idea that a doubling of atmospheric CO2 concentration will have a small effect on the distributions of heat and temperature — what is called the “luke warm” position.

Theo Goodwin

Alan McIntire says:
August 4, 2014 at 8:49 am
“This explanation as given doesn’t make much sense. If greenhouse gas absorption is really strong, it may INITIALLY block most of the outgoing infra-red radiation, but ultimately the gas will have to re-radiate as much as it blocks.”
How has Alan not nailed the point. If you claim that high concentrations of CO2 in the troposphere block radiation and, thereby, cool the stratosphere then you violate the fundamental assumption that radiation in equals radiation out. Or you have to invoke some explanation that does not belong to radiation theory.

Climate Weenie

It’s important to remember the difference between the two features.
Stratospheric cooling is a direct result of CO2 calculated from radiative transfer models alone ( the ones we have confidence in ).
The un-observed Tropical Upper Tropospheric Hot Spot is not from radiative forcing directly, but is a consequence of general circulation models with an imposed energy imbalance ( the models that we know are chaotic with lots of important sub scale phenomena ).
The TUT Hot Spot is also supposed to appear if the imbalance comes from solar forcing:
http://data.giss.nasa.gov/cgi-bin/cdrar/effjk.cgi?xx=efficacy&type=Rc&mod=E2SOx4&quantity=01&mean_gen=ANN&pscale=1&nobanner=0

MarkW

Could this cooling be the result of more efficient thunderstorms that result in less water vapor being transported to the stratosphere. The so called “Iris Effect”, predicted by Dr. Lindzen.

Bill H.

Wow, the quality of comments at WUWT ain’t what it was. Here we have a more or less uniform cry of sarcasm along the lines of “if things are getting colder it’s due to Global Warming”. If you guys want to undermine AGW theory by scientific reasoning as opposed to unscientific sarcasm you’d do well to find out something about the reasoning supporting the theory. The idea of AGW leading to stratospheric cooling was first proposed in 1967 by Manabe and Wetherald on the grounds that long wave radiation would increasingly be absorbed in the troposphere with increasing CO2 leading to less long wave radiatiion reaching the stratosphere – not the most difficult of ideas to grasp. Since that time it has remained a central prediction of AGW theory, not least because it would be a key indication of greenhouse gas forcing as opposed to solar or aerosol forcing, neither of which would be expected to lead to such cooling in the stratosphere. The predicted cooling was finally demonstrated conclusively by observation in 2011. As for this stuff about a supposed 60 year PDO cycle giving rise to a cycling in warming/cooling of the stratosphere, the evidence indicating persistent cooling over the 1952-2012 period (60 years) would seem to undermine this idea.
Still, keep trying folks: hatred of AGW theory seems to be a very powerful inducement for people to come up with multifarious and mutually contradictory alternative climate theories.

Stratospheric cooling is the better fingerprint.

MarkW

ren says:
August 4, 2014 at 9:20 am
————
Water vapor decreases rapidly with height because the higher you go, the colder it gets.

Radiosonde balloon data and satellite measurements also falsify the ‘hot spot’ prediction. Once again, the models were wrong.

@ Bill H
same reply applies
as given to Joe Bastardi
http://wattsupwiththat.com/2014/08/04/what-stratospheric-hotspot/#comment-1701329

PhilCP

To me, the absence of the “hot spot” is an even more devastating blow to the theory of AGW than even the pause. The hot spot is indeed a clear signature that CO2 can cause warming. Its absence is very telling.
Warmists sometimes respond that AGW is not the only thing that can cause the hotspot. While this is true, they are confusing the logic. Although the presence of the hotspot does not prove AGW, its absence pretty well disproves it.

Climate Weenie

“Radiosonde balloon data also falsifies the ‘hot spot’ prediction. Once again, the models were wrong.”
Well, the GCMs are wrong for the upper troposphere.
But the radiative models for the stratosphere remain correct.

Climate Weenie

“Still, keep trying folks: hatred of AGW theory seems to be a very powerful inducement for people to come up with multifarious and mutually contradictory alternative climate theories.”
Lots of irrationality to go around, including those who misuse radiative forcing to exaggerate climate effects and further ulterior motives.

Tom T

OMG not this junk again. This all goes back to a bad post by Gavin in 2004 where he incorrectly attributed the physical cause of stratospheric cooling.
http://www.realclimate.org/index.php/archives/2004/12/why-does-the-stratosphere-cool-when-the-troposphere-warms/
“14/Jan/05: This post was updated in the light of my further education in radiation physics.
25/Feb/05: Groan…and again. – See more at: http://www.realclimate.org/index.php/archives/2004/12/why-does-the-stratosphere-cool-when-the-troposphere-warms/#sthash.p67m6CdD.dpuf
#1 The stratosphere does not cool because radiation is being trapped in the troposphere.
#2 THE STRATOSPHERE DOES NOT COOL BECAUSE RADIATION IS BEING TRAPPED IN THE TROPOSPHERE!!!
#3. The stratosphere cools due to rising CO2 because the presence of O3 in the stratosphere makes CO2’s radiative properties dominate.
#4. Where there no or little O3 and the atmosphere un-stratosphied, AGW would warm the stratosphere up to the tipyy top .
There is no relationship between anthropogenic global warming and stratospheric cooling. They are different physical phenomenon with the same cause, rising CO2. Its not different than the relationship between plant fertilization and AGW. Both share the same cause but one is not proof of the other because they are a different physical process.
I think the authors of the paper know this because you can see from their parsing of words that they never attribute stratospheric cooling to anthropogenic global warming. They attribute it to CO2 which is true and they use CO2 and greenhouse gas interchangeably but they never make the physical connection between the actually greenhouse gas effect and stratospheric cooling. This is left to the reader to make the wrong connection. This is called lying by context something that is very common amongst academics because they have the emotional mentality of a 4 year old and cannot grasp that there are forms of lying beyond lies of commission.
In conclusion saying that stratospheric cooling is proof of anthropogenic global warming is like saying that plant fertilization is proof of anthropogenic global warming. No it is not they are different physical processes that share a common cause. Stratospheric cooling is proof of rising CO2 nothing more.

The stratosphere is warmest at the top and then cools as it descends to the tropopause as UV radiations is increasingly filtered out. Any changes in solar UV affect the stratospheric temperatures. If you look at satellite observations for stratosphere temperatures as depicted in Figure 1A Ramaswamy et al. (2006) Anthropogenic and Natural Influences in the Evolution of Lower Stratospheric Cooling. Science 311, 1138, there are 2 warm peaks in the early 80s and 90s corresponding to to sunspot peaks of each cycle. Sunspots cycles are excellent proxies for changes in UV radiation. The sun spot peak in the early 2000s is much lower and accordingly so is stratospheric warming is less. A weakening sun readily explains the cooling trend but the model results using anthropogenic forcing once a again obscure that relationship, yet modelers continue to suggest GHGs are cooling the stratosphere.