Despite the continuous rise of CO2 density, the surface air T stops rising since the beginning of the 21-st century. The attribution of this global warming slow-down to the sudden intensification of trade winds seems quite unconvincing, because the reason of this intensification remains unknown (for more details, see Nature Geo-science, Editorial from March, 2014)
First, there is no indication that surface air temperatures have stopped rising. Each decade continues to be warmer than the previous. To use anything less than a decade to fifteen years as a measure of climate change is to ignore the modulating impact of natural cycles (like watching the waves when trying to decide if the tide is coming in). When surface water in the Pacific is colder than average it cools the atmosphere, but this tells us no more about global warming than the spikes of warming that occur during an El Nino event. The correct measure we need to consider, and the best measure of what the future holds, is to consider total heat content of the atmosphere and oceans together.... remembering that 90% of this energy is locked in the oceans. The oceans have a hot flush and the atmosphere develops a fever :-) By this measure, global warming has continued unabated. There may be some background cooling effect from industrial aerosols/volcanoes, but there is also warming from decreasing albedo and the release of methane from the Arctic.... lots of feedback; but the bottom line remains unchanged. More greenhouse gases mean more energy in the ocean-atmosphere system, and like any physical system, the addition of more energy will have an impact.
This question is asked in the topic CLIMATE/Climate change:
climate is the AVERAGE weather or temperature over a period of decades. Thus a change or absence of a change over a short period does not belong to climate-science
Dear colleague ten Bring, the 15 year period is not a short time scale – it is a half the period of 30 years defined by the World Meteorological Organization as climatic period. In this context, a glance on the global average surface air temperature (T) reveals that during the passed ~15 years the T annual means fluctuate around a stationary mean (i.e. the positive trend in global mean T disappears) - e.g. https://www2.ucar.edu/climate/faq/how-much-has-global-temperature-risen-last-100-years.
Consequently, D. Kitchen’s statement that “Each decade continues to be warmer than the previous” is simply incorrect!
A good illustration of my words is presented in the attached Fig. presenting differences of decadal means of T2m (air temperature at 2 m. above the surface). It shows that over the globe, the mean values of T2m during the last 14 years (2000-2013) is cooler, with stronger effect in the polar regions (data are from ERA40 and ERA Interim re-analyses; monthly values). The similar tendency is also seen is T2m anomalies (i.e. deviations from corresponding decadal means) – showing that in 2000s the periods with T2m colder than decadal mean are observed more frequently that in previous decades.
As a last attempt to explain why the rise of surface T is interrupted, when the global concentration of greenhouse gases continuously increase, D. Kitchen offers a “new measure” of global warming – i.e. “the total heat content of the atmosphere and ocean”. However, recent studies based on the analysis of ARGO floats data show that positive trend in the rate of ocean heat changes also disappears (see for example: http://oceans.pmel.noaa.gov/index.html). Consequently, the presumption that T2m stop rising, because of the stronger heat uptake by the ocean seems also quite doubtful.
On the other hand, the D. Kitchen assertion that more greenhouse gases ensures rise of the accumulated energy in the atmosphere-ocean system is largely exaggerated, because the main impact in the greenhouse warming of the planet belongs to the tropospheric water vapour (~50-67%) and only about ~19-24% to CO2 [1]. Moreover, the modellings and measurements show that the greatest impact in the Earth’s radiation balance belong to the upper tropospheric water vapour − e.g. [2,3] – the variability of which could hardly be related to the warmer surface air T.
These and some other facts should stimulate the further studies related to the actual driver of climate variability (on a shorter – within a given climatic period, as well as on longer time scales – i.e. between different climatic periods)
[1] G.A. Schmidt et al., J.Geophys.Res., 115, D20106, 2010.
[2] Spencer & Braswell, Bull. Amer. Meteor. Soc., 78(6): 1097-1106, 1997.
[2] Inamdar, et al., J. Geophys. Res., 109: D06104 doi:10.1029/2003JD003980.
Dear Natalya.
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Really are not 15 years are 16 years according to the measure (GISS, NCDC, HadCRUT 3 or 4, ...), ie CO2 as the only driver of climate seems to me rather tottering.
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On the other hand, it seems interesting that to the extent that it extend the experimental measurements more accurately the slope of the curve of temperature variation decreases! The case of the probes ARGO is remarkable, the ocean stopped warming.
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What most surprises me are the explanations, since the amount of heat going into the bottom of the ocean, then return to a colder to a warmer part! Also now we were treated by a publication that justifies the "hiatus" by the action of successive El Niña, making the super El Niño of 1998-99 is considered climate and the latest Las Niñas like a freak!
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I looked at your article on geomagnetic field may send a note to bring another physical interpretation to the mystery.
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The current period of relative temperature stability is not the first one in recent temperature records, if you look at the 1940s to 1970s. That period was bracketed by 30-year periods of rapid warming. To me, this is beginning to look like a pattern of regular oscillation overlaid on top of underlying warming. In other words, in the absence of the GHG forcing, we would now be seeing a period of cooling. If we are in for another 15 years of relative stability, I worry that the political will to tackle GHG emissions will dissipate until temperatures pick up again, by which time it will be too late.
Dear Phillipe,
The problem is that if greenhouse gases (and particularly CO2) are not the main driver of climate variability (as my investigations show) the near future climate could really become cooler - independently of the CO2 density. Consequently, if society is prepared for continuing global warming, but the climate start cooling - this means that we have made a wrong prediction for the climate evolution!
For this reason I prefer to continue investigation in attempt to detect the actual drivers of climate variability. The existence of many unexplainable features in the past and current climate - especially its regional specificity - is a good hint that we know still quite a few about the reasons for climate changes.
Natalya
To assess climate CHANGE one thus needs a period of tow times 30 years at least. Why do you mention water vapor? It is known by every climatologist that water vapor is a stronger greenhouse component than CO2 but the increased CO2 is the driver of Climate Change.
Every climatologist knows that increased CO2 means warming: this is not the issue of the present difference in opinion between alarmist-climatologist and skeptical climatologists. The difference lies in the water and cloud feed-back
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Dear Harry.
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I think we already had this discussion elsewhere, just try to be synthetic.
The heart of this scientific discussion is not in negation of the greenhouse effect, but in appearance QUANTITATIVE. There are several motors in climate variability and discussion should be conducted not only in the mechanisms of feedback as the magnitude of intervention of each factor.
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Even not having an extended period to characterize the climate, sixteen or seventeen is already a term that should be analyzed to verify the quantitative aspect of each driver and feed-back mechanisms.
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You put in your text clearly recognizing that water vapor is a more important driver than CO2, but I see no effort of those whose CO2 almost the only explanatory variable in climate check "which leads this variation water vapor in the atmosphere. "Therein lies the point, all the explanations of the "alarmists" called in relation to the "skeptics", is considered as the amount of water vapor as something that is not understood and therefore should not be considered!
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The mechanism that causes the variation of water vapor is not known, one must look for the origin of its dynamics and not just ignore it, as said "alarmists" ignore the solar influence, because most do not know their mechanism than anything else.
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The so called hiatus clearly shows that the influence of other mechanisms being underestimated, he does not deny the existence of the greenhouse effect, but puts into question its quantitative aspect.
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Strange conversation. Water vapor is a feedback into global temperature change not a driver of temperature change. It is the most important GHG, but most of it precipitates within days of entering the atmosphere... there has to be something else there to maintain elevated temperatures. This is simple physics. In contrast, the addition of CO2 and other long-lived GHG drive climate change... they force climate to change. In the absence of these other GHG water would soon precipitate out following a cooling feedback loop and we would have a dry cold world. Why all this focus on the atmosphere when it accounts for less than 90% of the energy in the climate system? If we bring cold water to the surface through PDO or La Niña or AMO, the atmosphere will cool.... because the energy is transferred to the oceans. It does not magically disappear! Just look at NOAA data for ocean heat content at different levels to see that ever more energy is added. If you do not believe that, then tell me why we see sea level continues to rise at a rate that we can't explain without a substantial component of thermal expansion. Natalya's comment about heat in the atmosphere seems disconnected to me? How does she think the oceans are warmed? From below? The oceans are warmed across the air water interface by heat diffusion and mixing. They remove energy from the atmosphere- and because the heat capacity of water is so large compared to the atmosphere - they soon become a massive reserve of energy that modulates air temperature according to natural ocean-atmosphere cycles. Rogerio's point is correct. The the only issue we should discuss given the data is how much climate will change. The only real outstanding factor is clouds (now that we can dismissed solar influence after little global impact form the recent solar minimum) but the cloud data, (while still too limited for real comfort) suggest the impact of warming is neutral to small positive. This is where the policy makers come in. A rise of 1.5˚K on doubling CO2 is something we best respond to by adaptation. A rise of 3.0˚K really requires us to take action to avoid substantial damage to society and the environment. My take is that the chances of low sensitivity are getting smaller and of larger than predicted sensitivity getting larger... BUT this is the key question we need to answer and it is where we have least certainty.
as i have argued else where in various forms on various blogs
averaging annual temperature data is not all that meaningful - seasonal
and monthly averaging tends to be much more revealing (with real signals)
http://www.cpc.ncep.noaa.gov/cgi-bin/gl_Temperature-Monthly.sh
is a good place to start
and yes, about 94% of all excess heat energy is absorbed in the oceans
and here is a shameless plug
http://theenergycollective.com/wattheadguest/29150/global-temperature-continues-rise-primer-climate-baseline-instablity
but it does discuss the temp. anomaly "problem"
and I really need to update this so maybe I will in a couple of weeks and post the update in my projects area
An observationally based constraint on the water-vapor feedback
a good paper
see
http://onlinelibrary.wiley.com/doi/10.1002/2013JD020184/abstract
they derive, from the data, 2.2 +/- 0.4 watts per square cm^2 positive signal
over the period 2002-2209. This "extra flux" is similar to what 400 ppm of CO2
would give
@ G. Bothun nice comments... thank you. I will look at the sites you refer to.
@G. Bothun
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Dear Professor, I looked carefully at your article (http://theenergycollective.com/wattheadguest/29150/global-temperature-continues-rise-primer-climate-baseline-instablity) and make a small criticism the same, because it induces the reader to think some things are not correct. I'm sure this was not your intention, but for clarity I will take the liberty of making this complementation.
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For analysis of time variability in the United States the correlation between warm and cold phases of the PDO and AMO, seems perfectly consistent, but when one extrapolates the same for a curve of global warming it loses largely its value, mainly because at work are not defined which represent the phases of the PDO.
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The definition of PDO, as I put in another thread, does not mean that the North Pacific (65 ° N - 20 ° N) is heated or cooled when the values of the PDO index is positive or negative, as ENSO not the value of the temperature in the Pacific equatorial.
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Meteorologists just to annoy others and keep an exoteric notation, named a distribution of anomalies of temperature and barometric regime in the north Pacific warm phase and another cold phase.
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The PDO index Represents the particular spatial pattern of the sea surface temperature anomalies in the extratropical North Pacific (20N-65N), not the sea surface temperature anomalies themselves.
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As the warm phase of the PDO temperature anomalies along the U.S. are hot and the other side of the Pacific (Japan and Russia) are cold, the cold phase is the inverse reasoning warm PDO warm phase in the North American coast, perfect, but can not say that globally warm phase PDO in global temperatures in the North Pacific is hot!
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On the other hand, the PDO index is calculated by a normalized value of values of pressure, ie divided by the standard deviation from a relatively short period of time. .
As the reference period is a short series and the reference value does not represent the actual average normalization by standard deviation overestimates one side of the oscillations.
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Similarly the NAO index is based on the surface sea-level pressure difference between the Subtropical (Azores) and the Subpolar High Low.
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It is possible to establish correlations between the NAO and the North Atlantic temperature, but again this correlation is not always linear and sometimes out of phase.
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A small mistake I think in his work, which is the inability to use PDO cycle with El Niño / La Niña is that these two indexes are correlated and can not explain any phenomenon with rates that are not linearly independent!
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I also do not accept your argument that the values of the temperatures in the Pacific and Atlantic may be removed by the ENSO, PDO and NAO indices with 100 year of baseline , because as the extrapolation of all these indices for temperature (SST) should be made through a correlation between pressures at predetermined points (Tahiti and Darwin - Australia) for the Southern Oscillation Index (SOI) that make up the Azores and Enso Subpolar region.
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Despite these criticisms I fully agree with the final conclusion of the paper "When other factors are Considered on the future Increases range of temperature, such as the water vapor feedback loop and the methane release of the Arctic permafrost, the argument que global warming peaked in 1998 will prove to be both erroneous and silly. "other reasons that will not fit here raise them.
1. I am only discussing the Balinese US climate as being a function of the particular
PDO, NAO phase. I agree that a global extrapolation is not warranted.
2. The temperatures are not being "removed", the ENSO,PDO, NAO waveforms are used to determine the smoothing length in the monthly data.
@Filippo and @Bothun
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The hypothesis that much of the heat has been transferred to the oceans is relatively recent, it came when Kevin E. Trenberth and John T. Fasullo published an article in Science
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Tracking Earth's Energy - 16 april Science vol 328 pp 316-317 - http :/ / www.sciencemag.org/content/328/5976/316.full
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In this article there is a enigmatic graph showing the disappearance of about + 0.9-0.5W / m² of which is supposed to enter the atmosphere and that is in terms of cumulative amount of heat after 2005.
This article Trenberth, a prominent member of the IPCC, only emerged after the first inquiries about the amount of heat being released in magazines climate .
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LOEHLE Craig Cooling of the global ocean since 2003, Energy & Environment • Vol. 20, No. 1&2, 2009 - http://multi-science.metapress.com/content/cw17434027026726/)
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The graph of enigmatic Trenberth shows that the balance of power had an enormous difference between the inlet and outlet, and that there were several possible interpretations.
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1. The balance was wrong by overestimating or underestimating the input to output.
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2. Energy was getting "hidden" somewhere unknown.
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It is interesting to note that this "mistake" was noticed only after the temperature measurements of the oceans began to be properly made through the project Argo floats (http://www.argo.net/) until this time the measure of quantity heat in the oceans was made by are a mixture of thousands of readings using XBT (expendable bathymetres), bottles, and other methods (an example: Levitus, S. et al Global ocean heat content 1955-2008 in light of recently revealed instrumentation problems Geophysical Research Letters, VOL 36, L07608 2009 -. ftp://ftp.nodc.noaa.gov/pub/data.nodc/woa/PUBLICATIONS/grlheat08.pdf), these methods had the dubious accuracy as in the case of XBT + -2% in depth and 0.2 ° C in temperature (http://www.aoml.noaa.gov/phod/goos/xbtscience/fre.php) and were not collected continuously and periodically throughout the oceans. With more than 3,000 Argo floats passed to a precision Better than ± 0.005 and ± 0.002 psu ° C
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(http://www.seabird.com/technical_references/LongtermTSstabilityAGUDec08Handout2Pages.pdf).
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In short, after 2005 with the introduction of 3000 Argo sensors accurately 100 times superior to previous methods of measurement, the conclusion was reached that there had been an imbalance in the ocean / land / atmosphere Heat Content.
After all this confusion, begin to appear some theories and measures of accumulated amount of heat in the deep ocean, and most interesting of all in areas below 1900m, maximum depth reached by the Argo floats.
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My personal opinion is that this hidden below 1900m energy is a true fantasy that serves to justify a huge flaw in the estimates of heat fluxes.
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Dear All,
After a glance over the recent problems discussed in different blogs, I have been surprised how many scientists criticize the last IPCC report (R5). So it is risky to rely only on the information provided by IPCC.
Unfortunately, most of the information and interpretations, provided there, are selectively picked up. Moreover, results which do not confirm the idea for the Earth’s anthropogenic warming are broadly ignored.
One result (still mentioned in R4, but completely ignored in R5) is the fact that the greatest impact in the Earth’s radiation balance belongs to the upper tropospheric water vapor (see references in my first comment, as well as the IPCC R4, e.g., Box 8.1: Upper-Tropospheric Humidity and Water Vapour Feedback).
1. The main problem of the IPCC interpretation of H2O vapour role in climate variability is assumption that it is a feedback of the warming initiated by the greenhouse gases (GHG). Indeed the H2O vapour density in the lower and middle troposphere depends on the surface temperature (T). But its influence on the Earth’s radiation balance is very small, because all long-wave radiation absorbed by the lower-middle tropospheric water vapour is emitted back in the space (due to the higher atmospheric T at these levels). Near the tropopause, however, the H2O vapour is very cold and all adsorbed long-wave radiation at this level is trapped in the troposphere.
2. Consequently, the upper tropospheric (UT) water vapour does not depend on the surface T, and consequently could not be a feedback of the changing climate! Even in the tropics, where tropical convection reaches the UT levels, the amount of measured vapour turns to be only a half of that calculated by climate models – e.g. [1, 2]. Moreover, even during the passed several decades with dramatic increase of the global surface T, the tropical climate remains almost unchanged. The greatest warming is observed at middle-high latitudes.
Consequently, the main question for each climatologist should be: Who controls the variability of the UT water vapour?
My analyses show that the main factor affecting the UT water vapour is the lower stratospheric ozone (e.g. [3, 5]). Analysis of the global distribution of the O3−H2O connectivity is non-uniformly distributed over the globe, what corresponds very well to the regional character of climate response to global forcings. For example, none of the existent global forcings can explain the paradoxically warmer Greenland during the Little Ice Age − warmer by ~2K than the average Northern Hemispheric T, [5].
Taking into account the lower stratospheric O3 influence on the near tropopause water vapour, the problem of regional specificity of climate variations is easily explained through the geomagnetic field variations (in space and time) [1, 6]. The latter controls the intensity and depth of energetic particles precipitations in the atmosphere, where they trigger different chains of chemical reactions leading to destruction or formation of O3.
What concern the greenhouse gases, they obviously have some impact in the contemporary warming, but the leading place most probably belongs to the UT water vapour – in the role of an active driver and not a feedback effect.
So on the question: Why the H2O vapour is not used as an explanatory variable? The answer is – because it is assumed to be feedback (i.e. it only magnifies the GHG effect)
The role of the ocean: As pointed by D. Kitchen and G. Bothun, the ocean uptakes the heat from the surface (which is warmed first by the visible solar radiation and secondly by the greenhouse effect of the UT water vapour + smaller impact of clouds and GHG). However, in the case of continuously increasing GHG concentration and stabilized level of surface T, one should expect that the amount of the heat uptake by the ocean should increase – as a compensation for the unchanged T. The measurements show, however, that this is not the case - see for example: http://oceans.pmel.noaa.gov/index.html).
[1] S. Po-Chedley& Q. Fu, Discrepancies in tropical upper tropospheric warming between atmospheric circulation models and satellites, Environ. Res. Lett. 7 (2012) 044018 (8pp), doi:10.1088/1748-9326/7/4/044018
[2] D.M. Mitchell, P.W. Thorne, P.A. Stott & L.J. Gray, Revisiting the controversial issue of tropical tropospheric temperature trends, GEOPHYSICAL RESEARCH LETTERS, VOL. 40, 1–6, doi:10.1002/grl.50465, 2013
[3] Kilifarska N.A. Mechanism of lower stratospheric ozone influence on climate, Int.Rev.Phys., 6 (3), 279-290, 2012.
[4] Kilifarska N.A., V.G. Bakhmutov, G.V. Melnyk, The mystery of Antarctic climate change and its relation to geomagnetic field, Ukrainian Antarct. J., 12, 45-55, 2013.
[5] T. Kobashi1, D.T. Shindell, K. Kodera, J.E. Box, T. Nakaegawa & K. Kawamura, On the origin of multidecadal to centennial Greenland temperature anomalies over the past 800 yr, Clim. Past, 9, 583–596, 2013.
[6] Kilifarska N.A., V.G. Bakhmutov, G.V. Melnyk, Geomagnetic influence on Antarctic climate – evidences and mechanism, Int. Rev. Phys., 7 (3), 242-252, 2013.
The parameters you propose may well play a significant role. I am not an expert in your field, but from what I have read and understand from the data record, I formed the opinion that there is probably a greater impact than generally accepted from high energy solar/cosmic particle fluxes at high latitudes due to the interactions you suggest and possibly others. This is a component however, a part of the puzzle, not an explanation of global climate change. I look forward to more clear and objective proof in the future. As for now, and I am sure it must be frustrating, other researchers who do understand this field so not seem to agree with you. Still, this is one (of the few) fields where I am skeptical of the mainstream.
It is always good to point to deficiencies in climate models, but it would not be the first time that the models prove to be right and the satellite data wrong.
http://www.skepticalscience.com/satellite-measurements-warming-troposphere.htm
Or perhaps they converge. It does seem that not all the sources you quote completely adapt your solution as the answer to their problem. I would like to learn more, so I will read the paper you post above.
I am sorry, but I am not sure I understand what you mean about ocean temperature? Average surface temperature is variable on a decadal scale. Isn't total heat content more important? There is recent evidence (for example) of AADW warming.
http://onlinelibrary.wiley.com/doi/10.1002/2014GL059923/abstract
http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-12-00834.1
http://www.noaanews.noaa.gov/stories2010/20100920_oceanwarming.html
Thanks....
Quotes from your given references...
Ref 1..."it is not clear whether the difference is a result of
common biases in GCMs, biases in observational datasets, or both"
Ref 2... "When the models are con- strained in a more physically meaningful manner... we show robust evidence for good agreement in the low-mid tropical tro- posphere but with some (reduced compared to previous studies) discrepancy in the upper tropical troposphere."
Ref 5... "Climate modeling and proxy temperature records indicate that the anomaly is also likely linked to solar-paced changes in the Atlantic meridional overturning circulation (AMOC) and associated changes in northward oceanic heat transport."
Dear David,
If you look at the attached figures you will see that the beginning of the current century is actually cooler than the end of the previous one. This is well seen in the mean winter near surface air temperature (Fig.1) as well as in its anomalies (Fig.2).
Consequently, for now there is no AADW warming!
AADW (Aggravated Assault with a Deadly Weapon) - phu, it is even difficult to pronounce..... It is a pity that instead of doing science, some people fabricate abbreviations....
With regard to the explanation of the warmer Greenland during the Little Ice Age - by Atlantic meridional overturning circulation (AMOC) - you possibly know that the ocean circulation is driven in a large extent by the surface T!
So the explanation of regional climate variability by AMOC, which depends itself on climate, does not solve the problem.
About the model accuracy, you could look at the recent discussion "On the AR4′s projected 0.2C/decade temperature increase" at the blog: Climate etc.
http://judithcurry.com/2014/06/15/on-the-ar4s-projected-2cdecade-temperature-increase/
Note that the attached figure is deceptive. It states that it is decadal averages, but the 2000's average is 2001 - 2013, i.e. 14 years. The 2001 - 2010 decadal average is indeed higher than the 1990s, in fact every year in that period is warmer than the 1990s average. The additional years were lower, partly due to an extended la niǹa event, and an extended solar minimum. The figure indicates improper analysis of time series data, either accidental or intentional. As others have pointed out, due to the magnitude of natural variations, a 10 year period is too short to establish statistically meaningful trends.
Dear Christopher,
Formally you are right, so I have repeated the figures with taking the average 2000s surface air T and its anomalies over the period 2001-2010 (see the attached Figs).
You can see almost no difference in the mean T distribution and slightly more pronounced positive T anomalies in the Northern Hemisphere.
@Natalia
Thanks for the response. While I am personally confident in the overall projections of the IPCC based on the confluence of current research from many sources, I agree that sensitivity is the only real (big picture) remaining unknown in this debate. We still do not have a full understanding of the role of aerosols, cloud feedback or (nod to you) changes in polar climate due to the influence of high energy particle fluxes.. But we must remember that uncertainty may err in both directions and from what I understand, the greater probability is that the net impact of these factors will lead to an overall climate response that is above the average predicted. I get frustrated (not at you!) at those who seem to assume that uncertainty will always work in the direction of cooling.
Re the AMOC- indeed this is an open system, exchanging energy back and forth of the years, and transporting energy within the oceans. Complex. I think it is important to note that while surface air temperature is important, the rate and distribution of ice formation, plays a critical factor and (often overlooked) wind vectors over the North Atlantic and the behavior of deep and intermediate Antarctic Waters. This phenomenon presents in the North Atlantic, but it is the expression of a global system and not independent of global changes in energy content.
I also want to ask you about the statement "But its influence on the Earth’s radiation balance is very small, because all long-wave radiation absorbed by the lower-middle tropospheric water vapour is emitted back in the space (due to the higher atmospheric T at these levels). Near the tropopause, however, the H2O vapour is very cold and all adsorbed long-wave radiation at this level is trapped in the troposphere. "
This is not what I understand. I agree that an increase in water vapor in the lower troposphere will have little impact on temperature because the atmosphere is well saturated with GHG. The average photon does not make it very far before capture. As well-distributed GHG build up in the middle to upper troposphere however, and increase ambient temperature, water vapor levels will increase at these altitudes because average ambient temperature remains above the dew point for longer (water vapor stays longer before condensing and precipitating). IR capture at that level is thus enhanced (water vapor-GHG), but (and this is where I do not understand what you write) less IR actually escapes directly to space (apart from wavelengths taht escape through the atmospheric window). This, of course, should enhance mid tropospheric warming. As I understand it, the atmosphere is not saturated with GHG at this level, so net effect is to REDUCE the IR flux to space at this altitude because the photons are not able to avoid capture until they reach higher elevations. As atmospheric gases are colder at this new higher elevation, and emit IR with less energy, the overall effect is to reduce the net IR energy flux to space relative to the amount that arrives form the sun... and we see warming. As this is the troposphere, and we work with full convective overturn, any warming at any level in the troposphere will be expressed at the surface by adiabatic processes. In this way you might argue the global warming is an expression of changes in the upper atmosphere, but that is simplistic. What did I misunderstand from your argument?
Natalya asks:
"Consequently, the main question for each climatologist should be: Who controls the variability of the UT water vapour?"
I think there may be a strong solar influence on this quantity. here is a rough overlay plot I did of solar activity smoothed at 96months vs UT specific humidity.
https://tallbloke.files.wordpress.com/2010/08/shumidity-ssn96.png
I have no expertise in atmospheric physics but from what I've read and understood, solar variation in the EuV wavelengths has strong effects on ozone levels. I would hazard a guess that specific humidity will be affected too, via linked processes. I'll have a read of these two papers and see what I can learn:
Atmospheric radiation and atmospheric humidity
J. E. Harries 2007
DOI: 10.1002/qj.49712354402
The role of specific humidity fields in the diagnosis of stratosphere troposphere exchange
Lesley J. Gray
Michael Bithell
Barbara D. Cox
2012
DOI: 10.1029/94GL01909
Interesting. The first is nearly 20 years old, but the second suggests a mechanism. If (as seems possible) solar activity can increase instability across the trop/strat boundary this would impact water vapor levels at high altitude. I remember that for a good part of the 20th century there does appear to be a relationship between solar activity and surface temperature... that breaks down as the concentration of GHG in the atmosphere increases, so it is not a driving force for climate change today, but it is a factor.
David,
There is no breakdown in the relationship between solar activity and surface temperature if you consider that peak solar cycle amplitudes are not the whole story, and that the heat capacity of the oceans, their tidal cycles and their thermal inertia is such that solar derived energy can be stored in them on multidecadal timescales.
I made an empirical study to determine the solar flux value at which the oceans neither gain nor lose energy. This turns out to be equivalent to the average sunspot number across the 265 year period of record. Integration of the sunspot number as a culmulative total departing from the 'ocean equilibrium value' reveals that the Sun was increasing ocean heat content all the way from 1934 to 2003.
Dear David,
Sorry for the delayed answer, but I was very busy during the past months.
Now I’m trying to answer your question from 20 June: “What did I misunderstand from your argument?” regarding the role of H20 vapour in climate variability.
Analysis of the tropo- stratosphere temperature (T) profiles shows that the warming of the lower-middle troposphere, due to the greenhouse effect, is actually very small compared to the T changes in the upper troposphere and stratosphere. The attached Figs. compare averaged T profiles of 1960s and 1990s decades (full symbols) derived from ERA 40 reanalysis at two latitudes. Additionally is given comparison of the Ozone (O3) profiles for the same decades (open symbols). These two decades has been chosen in order to compare the T profiles in the beginning of the global warming with that of its maximum (i.e. the end of 1990s.
The Fig.1 illustrates quite well the weak warming of the lower and middle troposphere and a substantial cooling of the upper troposphere and stratosphere. Note that the maximal cooling corresponds to the strongest depletion in the O3 profile in the lower stratosphere. The middle tropospheric T is practically unchanged, so your theoretical imagination (i.e. increased middle tropospheric T will leads to the increased humidity and correspondingly stronger greenhouse effect) is not fully correct. Fig.2 shows additionally that ozone depletion and cooling of UTLS layer in 1990s is much less pronounced at tropical latitudes (lat=300N).
All this indicates that the upper troposphere-lower stratospheric (UTLS) temperature is strongly influenced by the O3 density and practically is unrelated to the surface warming. On the other hand, it is well known that the UTLS temperature determines the static stability of the layer. Thus cooling of the UTLS reduces static stability of the air, allowing its upwelling and bringing the wetter air masses from below at upper levels. Enhanced humidity, on its turn, entraps the Earth’s long-wave radiation into the troposphere – increasing the greenhouse effect.
Consequently, not the middle troposphere (supposedly influenced by the warmer Earth’s surface) but the upper tropospheric T (influenced by the O3 density) is the main factor determining recent global warming.
At this point the reasonable question that could be put is: Why the tiny concentration of the upper tropospheric H2O vapour should be more important than the abundant water vapour in the lower-middle troposphere?
It was first predicted by Spencer & Braswell (1997) and later confirmed by Inamdar & Ramanathan (2004) - based on satellite measurements, that the greatest impact in Earth’s radiation balance belongs to the upper tropospheric water vapour. The later authors show that the H2O vapour in the lower troposphere absorbs the infrared (IR) continuum in “atmospheric window” (8
There is another question in this topic
Difference between climate (natural) variability and (anthropogenic) change.
I notice that in the title of this question the term variability is used or should it be "change"?
Like to remind that climate change can only be assessed over periods in which the variability is averaged out; this depends on the amplitude of the differences per year/decade/NAOpattern etc
Hi Harry,
Indeed the current warming of Earth’s climate is classified from some authors as a “change” – i.e. as unusual warming, related to the human activity.
Paleoclimatic records show, however, that such high concentrations of CO2 (accompanied with warmer climate) has been observed in previous epoch. So for now - it seems that the current warming is not an exceptional in the Earth’s history. For this reason my question is related to “climate variability”, but not to “climate change”.
Natalya,
You accept a correlation of T and CO2. Well, it is without doubt that mankind has produced over a very short period, compared to paleoclimate eras, a formidable increase in CO2. So why are you questioning the anthropogenic cause of the current temperature increase? Also, we are talking about a period of less than a century, because it is only in the last 50-60 years that the CO2 has accumulated and its increase is large enough to see a significant change that is higher than the annual/decadal variability in the temperature,
Harry
Hi Harry,
I didn't exclude a priory the importance of CO2 increase in current state of the climate. Moreover, in the beginning of my interest to climate variations I have trusted to the IPCC estimations for the dominant importance of the greenhouse gases (GHG).This confidence was supported also by my own experience in modelling the climate response to different forcings.
Later on, however, going deeper into the problem, I have started to see some discrepancies and subjectivity of the research on which the IPCC reports are based on.
Recently more and more people realize that there is something wrong in the IPCC assessments and attribution methodology. As a result - the doubt regarding the models' predictions for the future evaluation of Earth's climate continuously increases.....
Concerning to the "sharp" T increase during the period 1970s-1990s – there is another "trick" used in the methodology applied by the IPCC scientists.
The abrupt increase of T anomalies, accompanied by a decoupling between natural forcing and climate response (see attached Fig.1or IPCC AR5, p.876, box 10, Fig.1a), is a result from two main assumptions made in the IPCC statistical analyses of the surface T: (i) assumption for stationarity of climatic means; and (ii) assumption for linearity of the relations between forcing factors and climate response. The non-linearity of the external forcing and climate is already discussed in some of my papers [e.g., 1, 2]. So here I'll bring you attention to the importance of the non-stationarity of climatic means. To understand my point, please look at the attached Figs.2 & 3.
The Fig.2 illustrates the winter near surface air T variability during the period 1957-2012 (blue dots), at lat=400N. Additionally are shown dynamically varying T mean (continuous red curve) – calculated as 11 year running average, and stationary T mean (blue line) – i.e. the average over the entire period.
The Fig.3a shows the T anomalies (i.e. deviations from the climatological mean – dynamically varying or stationary). It is well seen that “stationary” anomalies are biased toward their negative values in the period 1960-1990 – when the stationary mean is higher than dynamical one. In the period afterward “stationary’’ means are biased toward their positive values – when the stationary mean is lower that the dynamical mean. The trend of stationary means is accordingly positive, while that of “dynamical” anomalies is close to zero.
If, however, one take as a reference mean the averaged T value over the period 1960-1990 – as is done in the previous IPCC AR4, then the trend of the derived anomalies’ time series is additionally increased (see Fig.3b).
In the current AR5 the IPCC experts go even further – expanding the analysed period to the range 1861-2012, they have chosen as a reference mean the averaged T for the period 1880-1920 – i.e. the lowest temperature during the examined period! This means that all T anomalies afterward are positively biased, what additionally increases their trend. This leads to a decoupling of climate variability from the natural forcing (e.g. the energy emitted by the Sun) – suggesting that the only reason for the current warming is the anthropogenic factor.
However, if you analyse the dynamically varying T mean (the red curve in Fig.2), you will notice that the climatic mean of surface air T varies with a period of 50-60 years. In the first half of this period the climatic mean is lower than the stationary mean (calculated over the entire period) - suggesting a cooling of the climate, while in the second half period – above the stationary mean (suggesting a climate warming). There are several attempts for explanation of this long-term climate variability – e.g. “stadium wave” of J. Curry (the author of “Climate etc.” blog) or recent Science paper of Chen and Tung – attributing this feature to Atlantic meridional overturning circulation [3].
Although these attempts are step forward in understanding the Earth’s climate variability, they have serious weaknesses – relating the long-term climate variability to the internal modes of climate system, the forcing factors of which are also unknown.
Our explanation – relating the lower stratospheric O3 and water vapour to the intensity and depth of energetic particles’ penetration into the Earth’s atmosphere, controlled on their turn by the helio- and geomagnetic fields, has many advantages: (i) It has well defined physically based logic; (2) It is confirmed by the existing lower stratospheric data for ozone and humidity, near surface air T, galactic cosmic rays, geomagnetic field, etc.; (3) It is able to explain many of the puzzling features of climate variability like regionality of climate response to the uniform global forcing, etc….. And I’m stopping here.
Please, excuse me Harry, for this long post, but may be it will open the peoples’ eyes for some deficiencies in statistical analyses supporting the prevailing idea for a dominant role of the GHG in the contemporary climate stage.
With best regards:
Natalya
Natalya
That is indeed quite a long post/answer.
I like to respond by item and focus on the ones that I feel comfortable with.
1. citation "Recently more and more people realize that there is something wrong in the IPCC assessments and attribution methodology."
I'd like to see names references and quantification of the "something wrong".
2. A climate model needs a starting point and that must be a climate period of at least 30 years. From thereon attribution of the change can be attempted. These are attempts and "IPCC" does not claim that the attempts are the final answer.
3. What is the mechanism for the effect of cosmic radiation on climate and specifically what changes are there. There is another question in this topic of Climate Change of Researchgate on this issue; the author of the section in AR5 gives the background for the conclusion that it is of minor importance. Fact is that particle intrusion cannot affect clouds (my own field of expertise).
4. The AMOC is for me quite an enigma and you are right with a oscillatory behavior it is affecting mean T in the NH.
Dear Henry,
A detail discussion of strengths and weaknesses of Climate models is available on the Judith Curry’s blog “Climate etc.” For example you could look at “Model structural uncertainty – are GCNs the best tools?” or “Can we trust Climate models”, although there are other interesting discussions.
My own concerns, regarding climate ability to describe properly the long-scale climate variability, are related to the noticed positive humidity bias of GCMs in the upper troposphere [1, 2]. I’ll not comment the naive statement postulated in [2] that this bias does not influence modeled climate, because the latter depends on the moister anomalies, but not on its main value ….. (What is obviously wrong, because the H2O vapour mean value is not constant with time. It varies and actually its long-term variations determine climatic variations)!
Here I would like to share with you my own experience. Recently I have decided to use the 20 century reanalysis, produced by the NCEP Global Forecasting System (Model of NOAA NCEP Environmental Modeling Center) – supposing to expand the period of my investigations backward to 1871.
What was my surprise, however, when I have revealed the absolute inconsistency of the specific humidity offered from this reanalysis?
To illustrate my words, the time series of specific humidity at 150 hPa, at lat=500N and four longitudes is show in the attached Fig.1. The opposite non-linear trends found at 00E, -1800W and 900E, -900W longitudes is physically non-explainable and contradict to the ERA40 & Interim reanalyzes (see attached Fig.2). On the other hand, if you took the zonally average humidity, you will have the well-known picture of continuously increasing upper troposphere-lower stratospheric (UTLS) water vapour – see Fig.3. Note also that the Specific Humidity in the 20 century reanalysis is on average 3 times higher than that of the ERA reanalyzes.
Regarding the IPCC “attempts” to explain and to model climate variability – the sentences like “It is extremely likely that ….” does not sound as an attempt (to my mind). Moreover, your opinion regarding the galactic cosmic rays (GCR) influence on climate is formed by the “reliable” source like AR5 and you hardly could change it.
There is, however, much more likely mechanism for GCR influence on Climate (than their influence of the clouds’ cover) and this new mechanism consist of the following chain of links:
1. Ozone production near the tropopause through ion-molecular reactions, initiated by GCR, which alter the ozone balance at these levels. This mechanism appears to be important mostly in the Northern Hemisphere – due to the strength and configuration of geomagnetic field [3];
2. The ozone variability on its turn alters the tropopause temperature – through its high ability to absorb electromagnetic radiation (solar and long-wave Earth’s radiation);
3. The variations of the tropopase T, on their turn, determine the variations in static stability of the upper tropospheric air, which increases or decreases the amount of water vapour in the region. Thus cooling of the tropopause increases air masses instability allowing upward propagation of the wetter air from below. In opposite - warmer tropopause suppresses the vertical motions (for more details see references [3, 4]);
4. The near tropopause H2O vapour, however, has the greatest impact in the Earth’s radiation balance (see my previous comments on this topic) – thus altering warming of the surface T (in periods and places with increased H2O vapor), or cooling (in periods and pleases with decreased near tropopause humidity).
References:
[1] Pierce, D. W., T. P. Barnett, E. J. Fetzer, and P. J. Gleckler (2006), Three-dimensional tropospheric water vapor in coupled climate models com-pared with observations from the AIRS satellite system, Geophys. Res.Lett., 33, L21701, doi:10.1029/2006GL027060.
[2] John V.O. and B. J. Soden, Temperature and humidity biases in global climate models and their impact on climate feedbacks, Geophys. Res.Lett., 34, L18704, doi:10.1029/2007GL030429, 2007
[3] Kilifarska N.A., V.G. Bakhmutov, G.V. Melnyk, Geomagnetic influence on Antarctic climate – evidences and mechanism, Int. Rev. Phys., 7 (3), 242-252, 2013.
[4] Kilifarska N.A. Mechanism of lower stratospheric ozone influence on climate, IREPHY, 6 (3), 279-290, 2012.
With best regards:
Natalya
You do not have to point out the site of Judith Curry.
And furthermore I like a structured book better than a more pamphlet-ish blog; therefore I like to study the IPCC-reports on uncertainty. Also, I like the more quantitative sites of other skepticists better than that of JC
whatsup or rather clivebest, who gives a very good popular idea of the greenhouse warming without hydrol feedback.
As for ozone I am familiar with the lower trop formation mechanism but not for upper trop or stratosphere
In my recent papers I have proven that climate variability is solar originated so CO2 has almost no effect on climate change. With time temperatures shall even have a steep drop so it will be further demostrated that CO2 is irrelevant to the case.
it is very high but the point is that I have discovered the mechanisms in solar activity, it's variability over time and the derived climate variability, so it's laws of nature and as such it's proven.
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