(Perturbation Calculations of Ocean Surface Temperatures.)
Guest essay by Stan Robertson, Ph.D., P.E.
1. Introduction
It is generally conceded that the earth has warmed a bit over the last century, but it is not clear what has caused it, nor whether it will continue and become a problem for humanity. There is a possibility that some of the warming has been caused by anthropogenic greenhouse gases, but it is also likely that the sun has been partially responsible. The arguments that are advanced to say that humans caused it and that it will become a serious problem rely on models that have not been validated and positive feedback effects that have not been shown to exist, at least at the hypothesized levels of effectiveness. The apparent weakness in the argument that the sun has been a major contributor is that satellite measurements of Total Solar Irradiance (TSI) have not shown changes large enough to have directly produced the warming of the earth over the last half century. But what about indirect effects? Is it possible that the sun exerts control in some indirect way? In these notes I recapitulate the evidence that this is the case by showing that the variations of TSI cannot provide the energy that is necessary to account for the warming of the oceans during solar cycles.
TSI, as measured above the earth’s atmosphere varies by about 1.2 watt/m2 over a nominal eleven year solar cycle (h/t Leif Svaalgard) primarily at wavelengths shorter than 2 micron. The dominant harmonic variation of TSI would thus have an amplitude half this large, or about 0.6 watt/m2. About 70% of this enters the earth atmosphere. Averaged over latitudes and day/night cycles, about one fourth of this 70%, or ~0.11 watt/m2, on average, enters the upper atmosphere. Since only about 160 watt/m2 of 1365 watt/m2 of incoming solar radiation at wavelengths less than 2 micron reaches the earth surface, the amplitude of short wavelength TSI reaching the earth surface would be only (160/1365)x0.6 = 0.07 watt/m2. However, about half of the difference between 0.11 and 0.07 watt/m2 eventually reaches the earth surface as scattered thermal infrared radiation at wavelengths greater than 2 micron. Thus the average amplitude of TSI reaching the earth surface in all wavelengths would be about 0.09 watt/m2. So the question is, just how much sea surface temperature variation can this produce?
Several researchers, including Nir Shaviv (2008), Roy Spencer (see http://www.drroyspencer.com/2010/06/low-climate-sensitivity-estimated-from-the-11-year-cycle-in-total-solar-irradiance/) and Zhou & Tung (2010) have found that ocean surface temperatures oscillate with an amplitude of about 0.04 – 0.05 oC during a solar cycle. (In fact, all of the ideas that I am presenting here were covered in Shaviv’s work, but it has not gotten the attention that it deserves.) Using 150 years of sea surface temperature data, Zhou & Tung found 0.085 oC warming for each watt/m2 of increase of TSI over a solar cycle. Although not strictly sinusoidal, the temperature variations can be approximately described in terms of a dominant sinusoidal component of variation with an 11 year period. Thus the question to be answered at this point is, can 0.09 watt/m2 amplitude of variation of TSI entering the oceans produce temperature oscillations with an amplitude of 0.04 – 0.05 oC?
The answer to this question depends on the average thermal diffusivity of the upper oceans. That is an unknown, but not unknowable, quantity. Thermal diffusivity is the ratio of thermal conductivity to heat capacity. The upper 25 to 100 meters of oceans are well mixed by waves and shears. These are mixing zones with high thermal diffusivity and correspondingly small temperature gradients. Diffusivities are lower at greater depths. Bryan (1987) has found that thermal diffusivities ranging from 0.3 to 5 cm2/s are needed to account for the temperature profiles below the mixing zone. In my first trial calculations of the energy flux necessary to account for the temperature variations, I tried values of thermal diffusivity in the range 0.1 – 10 cm2/s and found that the TSI variations were generally inadequate to produce the sea temperature variations over a solar cycle. But there was wide variation of calculated energy flux. Larger values of thermal diffusivity required more heat because more was able to penetrate to the depths, but even for 0.1 cm2/s, the required input was double the TSI variations that reach the earth surface. Fortunately, there is a way to constrain both the value of the thermal diffusivity and the heat input. It consists of first matching the measured trends of surface temperatures and ocean heat content over time. Measurements of these were reported by Levitus et al. (2012) and are available from http://www.nodc.noaa.gov/OC5/3M_HEAT_CONTENT/ .
In the calculations described below, I have used the data from 1965 to 2012 for ocean depths to 700 meters. Sea surface temperatures and ocean heat content began to increase after 1965. Only about a third of the increase of heat content occurred at depths below 700 meter. Since little heat migrates below this depth over 11 year solar cycles, it is preferable to use the 0 – 700 m data for the purpose of calibrating the thermal diffusivity
2. Heat Transfer Perturbation Calculations
For the calculation of sea surface temperature and sea level changes, we can treat the variations of radiations entering and leaving atmosphere, lands and oceans as minor perturbations on an earth essentially in thermal equilibrium. Ocean mixing zones, thermoclines and other features of the temperature profiles remain largely as they were while small radiant disturbances produce minor variations of temperature starting from zero, and imposed at each depth. Thus the effects of these disturbances can be modeled as one-dimensional energy flows into a medium at uniform temperature. Such “perturbation calculations” are among the most powerful analysis techniques used by physicists and engineers and are widely used. The energy equation to be solved in this case is:
http://i1244.photobucket.com/albums/gg580/stanrobertson/equation_zpscea297ad.jpg
Where T is the temperature departure from equilibrium at depth , z, and time, t. q is a perturbing radiant flux entering the surface, u the absorption coefficient, c is absorber heat capacity and k its thermal conductivity. The rate of heat transfer by conduction processes is controlled by the thermal diffusivity, which is the ratio k/c.
As a one dimensional heat flow problem, it is straightforward undergraduate level physics or engineering to numerically solve the equation above for the expected changes of surface temperature as surface radiant flux varies. In my calculations, temperature changes were calculated for 1.0 meter increments of depth in the oceans. Two cases were considered. In one
case the surface radiation perturbation was assumed to increase linearly with time. This corresponds to the ocean conditions for the period 1965-2012. In the second case, it was assumed to vary as a cosine function of time with the 11 year period of the solar cycle. The cosine function provides both some positive and some negative variation in the first half cycle, which helps to minimize the transients of the first few years.
I treated q and thermal diffusivity, (k/c), as input parameters that were chosen to provide agreement with the observed sea surface temperature variations and ocean heat content measurements (https://www.ncdc.noaa.gov/ersst/ ). The absorption coefficient, u, was entered in piecewise fashion. Only the deep UV radiations penetrate to depths below 10 meter, but conduction takes energy to much greater depths. For the values of u chosen, only 44.5% of the surface energy flux goes deeper than 1 meter, 22.5% below 10 meter and 0.53% to 100 meter (h/t Leif Svalgaard). Thermal diffusivity of oceans was assumed to be 0.3 cm2/s below 300 m. This accords with Bryan’s estimates below the mixing zone, but little change of results occurred for values as low as 0.1 cm2/s. The required heat inputs are relativity insensitive to the thermal diffusivity below 300 meter. For the shallower depths, thermal diffusivity was varied until trends in accord with observed temperatures and heat content were produced.
It is necessary to maintain an energy balance at the sea surface in approximate equilibrium with the incoming solar radiation. As estimated by Trenberth, Fasullo and Kiehl (2009), about 160 watt/m2 enters the surface, on average. At a mean temperature of 288 oK, the sea surface will emit about 390 watt/m2 of surface thermal infrared radiation at wavelengths longer than about 2 micron, however, about 84% of that is returned as back scattered radiation. The rest of the energy balance is provided by evaporation and thermal convection, which remove about 59% of the heat from the surface. From the standpoint of merely wanting to know how much heat is required to change the ocean surface temperature, it is possible to maintain a proper energy balance without delving into the messy details of evaporation, convection and infrared absorption in the first few millimeters of water. The temperature variations at one meter depth will not be measurably different from those at the surface for the thermal diffusivities of interest here. If we merely want to know what net energy flux entering the surface is required to make the water temperature at one meter depth oscillate with an amplitude of 0.04 – 0.05 oC , then all we need to do is account for the outgoing surface infrared emission and let 41% (160 watt/m2 / 390 watt/m2 = 0.41) escape. At the present 288 oK, the earth radiates an additional 5.42 watt/m2 for each 1 oC increase of surface temperature. In the case of surface temperature being perturbed by 0.04 oC, an outgoing additional 0.22 watt/m2 would be generated and 0.09 watt/m2 was allowed to escape. This nicely balances the amplitude of TSI variations that reach the earth’s surface.
3. Linear heating:
In these calculations, the aim was to find the heat input and thermal diffusivities necessary to account for the observed surface temperature increase (http://www.nodc.noaa.gov/OC5/3M_HEAT_CONTENT/ )Extended Reconstructed Sea Surface Temperature) and the increased ocean heat content (OHC 700) that have been reported by NOAA. Since surface temperatures had not been increasing in the early 1960s, but began to increase in the last half of that decade, I chose to start calculations with linearly increasing heating in 1965. I found that the ocean heat content to a depth of 700 meters was quite sensitive to the thermal diffusivity used. The best results that I have been able to obtain were for a thermal diffusivity of 1 cm2/s to 300 meter depth and surface heat input increasing at a rate of 0.31 watt/m2 per decade. These are shown on the graph below with calculated trends shown by the green and black lines. On a time scale of 50 years, most of the heat accumulates at relatively shallow depths. To better reflect a realistic thermal diffusivity for greater depths, I used a lower value of 0.3 cm2/s below 300 meter. That has little practical effect on a 50 year times scale, but would be necessary if one wanted to extend the calculations for several centuries while surface heating perturbations had time to penetrate to much greater depths.
http://i1244.photobucket.com/albums/gg580/stanrobertson/OHC700_zpsb9e34e91.jpg
Figure 1. Ocean heat content 0 – 700 meter and surface temperature trends according to NOAA. Blue and green lines show trends calculated for the parameters shown.
These calculations establish some parameters that do a good job of representing the thermal behavior of the upper oceans, however, if one looks closely at the data trends in the graph, it is apparent that both surface temperature and ocean heat content have considerably slowed their rates of increase in the last decade. This makes it unlikely that greenhouse gases are the cause of the rate of heating needed to explain the previous trends because their effects should have become enhanced rather than diminished. It might also be noted that a similar warming trend occurred in the first half of the previous century before anthropogenic greenhouse gases could have contributed significantly. Thus it is more likely that both warming periods had natural origins.
Obtaining simultaneous fits to the ocean heat content and sea surface temperature trends with only two free parameters, thermal diffusivity and surface heating rate, is quite confining. Acceptable, but noticeably worse, fits than shown above, were obtained with thermal diffusivities ranging from 0.8 to 1.2 cm2/s and heat inputs ranging from 0.29 to 0.33 watt/m2. Based on previous calculations for sea level data, I was initially inclined to think that larger thermal diffusivities would be necessary, but larger values let more heat penetrate to greater depths than the amounts of heat reported by Levitus et al. In addition, I was chagrined to learn that most of the variation of sea level that accompanies solar cycles is caused by evaporation rather than thermal expansion.
Solar Cycles:
The process of choosing thermal diffusivity and surface heating rates to accord with observations provides a sound basis for calculating what to expect for the temperature variations during solar cycles. In this case we can use the thermal diffusivity of 1 cm2/s that is required of the ocean heat content results as an input parameter and choose the heat input that is required to produce temperature variations of 0.04 – 0.05 oC amplitude. Producing sea surface temperature variations with an amplitude of 0.04 oC requires a surface heat input of 0.33 watt/m2, as shown below:
http://i1244.photobucket.com/albums/gg580/stanrobertson/solarcycle10_zpsa3b8b0ee.jpg
Figure 2. Radiant flux, ocean temperature oscillations, and sea level variations for three solar cycles of eleven years each. The entering flux shown here is the value of q = 0.33 watt/m2 needed to drive the variations of surface temperature of 0.04 oC with ocean thermal diffusivity of 1.0 cm2/s to depth of 300 m. The amplitude of thermosteric rate of change of sea level was 0.47 mm/yr. Temperature lags the driving energy flux by 15 months. The thermal expansion coefficient of sea water used here was 2.4×10-4/ oC.
I believe that this settles the issue of what is required to produce sea surface temperature oscillations with an amplitude of 0.04 oC. The solar TSI variations that reach the earth’s surface are smaller than the 0.33 watt/m2 needed to account for sea surface temperature variations by a factor of 3.6 for this smallest estimate of sea surface temperature variability.
Although the estimated 0.33 watt/m2 that is required to explain the surface temperature variations is large compared to the amplitude of TSI variations that reach the surface, it is still only about two parts per thousand of the 160 watt/m2 of solar UV/VIS/NIR that reaches the earth surface. There are many possible ways in which the sun might modulate the surface energy flux to this extent. These include modulation of cloud cover and small spectral shifts in the energetic UV that might modulate ozone absorption or produce shifts of the effective sea surface albedo. It would seem to be a fairly direct radiative effect, rather than feedback, since it must vary in phase with the solar cycle.
In summary, my calculations based on energy conservation considerations imply that the sun modulates the ocean temperatures to a much greater extent than can be provided solely by its TSI variations. The great question that desperately needs an answer is how does it do it? It should be easily understood that solar effects would not necessarily be confined to cycles. More likely, the sun has been the driver of the large changes of temperatures of the Roman and Medieval warm period, the Little Ice Age, and the recent recovery from it without requiring large changes of its own irradiance. When we understand how the sun does this, we will have begun to understand the earthly climate.
###
Biographical note:
Stan Robertson, Ph.D, P.E, retired in 2004 after teaching physics at Southwestern Oklahoma State University for 14 years. In addition to teaching at three other universities over the years, he has maintained a consulting engineering practice for 30 years.
References:
Bryan, F., 1987: Parameter Sensitivity of Primitive Equation Ocean General Circulation Models. Journal of Physical Oceanography, 17, 970-985. (PDF available here http://journals.ametsoc.org/doi/abs/10.1175/1520-0485%281987%29017%3C0970%3APSOPEO%3E2.0.CO%3B2
Levitus, S. et al., 2012 World ocean heat content and thermosteric sea level change (0–2000 m), 1955–2010, Geophysical Research Letters, 39, L10603, doi:10.1029/2012GL051106, 2012 http://onlinelibrary.wiley.com/doi/10.1029/2012GL051106/abstract
Shaviv, Nir 2008, Using the oceans as a calorimeter to quantify the solar radiative forcing, Journal of Geophysical Research, 113, A11101 http://www.sciencebits.com/files/articles/CalorimeterFinal.pdf
Trenberth, K., Fasullo, J., Kiehl, J. 2009: Earth’s Global Energy Budget. Bull. Amer. Meteor. Soc., 90, 311–323. doi: http://dx.doi.org/10.1175/2008BAMS2634.1 www.cgd.ucar.edu/staff/trenbert/trenberth.papers/TFK_bams09.pdf , Fig. 1
Zhou, J. and Tung, K. ,2010 Solar Cycles in 150 Years of Global Sea Surface Temperature Data, Journal of Climate 23, 3234-3248 http://journals.ametsoc.org/doi/abs/10.1175/2010JCLI3232.1
Leif writes “SSI is very difficult to measure. The errors are of the order of 10% or more, while the error on TSI is thousands of times smaller.”
And yet SSI is the area where the sun could have the most direct influence in the different levels of the atmosphere. Changes in UV resulting in changed atmospheric O3 concentrations and altitudes could have larger impacts on the surface temperature than the wattages needed to make the changes. Its a big unknown, routinely brushed aside by Leif.
Do you pretty much exclusively focus on TSI because that’s your area of expertise Leif?
TimTheToolMan says:
October 13, 2013 at 5:49 am
Changes in UV resulting in changed atmospheric O3 concentrations and altitudes could have larger impacts
‘could have’. But show that they ‘do have’
Do you pretty much exclusively focus on TSI because that’s your area of expertise Leif?
Not at all. The UV is actually where most of my interest lies. The UV creates the ionosphere and modulates the diurnal variation of the geomagnetic field, so is very important in studying the magnetic effects [which is my specialty]. Especially for long-term studies. We have know [and have data for] this modulation since 1722 when it was discovered by George Graham. The data shows that UV since then has varied just as the sunspot number and [therefore] TSI. So any changes in atmospheric properties must follow that same rythm, and yet there is little evidence of it in the climate record.
Leif says “So any changes in atmospheric properties must follow that same rythm, and yet there is little evidence of it in the climate record.”
SSI varies with TSI but what about the strength of the relative proportions of the wavelengths? There is no data for that and so we cant be sure if there are longer term changes. So for example the amount of UV in recent solar cycles may on average be a little higher (or lower) than in the past.
lsvalgaard says:
October 13, 2013 at 6:13 am
“The data shows that UV since then has varied just as the sunspot number and [therefore] TSI.”
First, as you surely know the causal relation between sunspots and TSI is negative – sunspot occurence on the disk causes TSI to drop – their correlation is typical example of correlation which has nothing to do with causation, because the factor – solar activity – which makes them correlate is independent from the two. Also if you have little or no sunspots the correlation of the TSI and SSN tends in principle to zero as tends to zero the SSN correlation with UV. So the relation between SSN and TSI and UV variation is not so simple as that UV [and therefore TSI] varies “just as the sunspot number”, it is mathematically ruled out straight away.
Now, the SORCE SIM data quite look, that what you say could even not be the case.
It seems to show, that generally the relative variability in UV region rises steeply with frequency (with descending wavelength) and that the XUV and EUV have considerably different than Planck distribution (maybe because Sun obviously isn’t a blackbody and doesn’t behave exactly like that – especially not in the UV region).
But the real point is that the absolute variability in UVA+UVB region is considerably higher than the variability of the TSI over whole spectrum and especially considerably higher than the variability in visible and IR region, which in some regions seem even show quite strong antiphase behavior. (see here
Basically the data show that the UVA+UVB+part of theNIR make the solar cycle characteristic signal, offsetting antiphase behavior in regions of visible and IR spectrum above 1 micrometer (see here). And because that part of the IR is unlike the UVA+UVB largely blocked by atmospheric water content (which is in larger quantities present especially above ocean and especially in well insolated regions due to higher air temperature) to get to surface, it could be argued that if the SORCE spectral data are indeed corresponding to reality without substantial error, then the variability of absolute UVA+UVB spectral irradiance of the surface during the solar cycle could be considerably higher than variability of the TOA TSI, suggesting, although it could seem being a paradox, that also surface TSI variability could be bigger than the TOA TSI variability due to absorbed part of the IR around the 1125nm,1375nm and 1875nm regions.
When I go back to the topic of the above article and I couple this to the steeply rising water extinction coeficient (from the minimum around 430nm deep blue) with descending wavelength in the UVA+UVB region I would bet that if the above analysis or generally a correlation of SST to solar activity would be done with the UVA+UVB absolute variation between solar cycle minimum and maximum calculated from the spectral data showing such behaviour as SORCE SIM data (reduced to that at the surface after passing atmosphere and filtering out the absorbed part of the NIR) and also adressed the other obvious problems with the analysis in the article I described in the post above (October 12, 2013 at 9:06 am), especially the clearly out of reality explicite or implicite assumptions that ocean receives average insolation, reflects 6.7% and that it radiates at ε=1 the resulting factor would be in my opinion considerably closer to 1 than the 3.6 and maybe even the closing question from the article “how the Sun does it”, would be answered.
Unfortunately the SORCE SIM data cover quite short period in time (04/21/2013 – 09/25/2010) not even over 1 solar cycle and not covering the cycle peak period, so the variability over solar cycle would need to be partially interpolated, which would of course introduce some more uncertainty.
The sun does interact with the earth beyond light.
Dr. Viktor N. Bokov predicts earthquakes based on solar storms.
He says, earthquakes are caused by the weight of the atmosphere in the tectonic plates.
There are cycles in the circulation of the atmosphere that allows us to predict future weather and that earthquakes, oddly enough, are regulated by the Sun and follow certain patterns that allow their prevention.
He works with the Vangengeim-Girs meteorological index. Studying three types of circulations C, W and E, Bokov is able to predict long-term weather, after reconstructing these patterns of the last thousand years.
Bokov’s Site: http://quake_vnb.rshu.ru/index_eng.html
V-G Index: http://www.fao.org/docrep/005/y2787e/y2787e03.htm
And here is a google-translated interview with graphs explaining his method.
http://translate.google.es/translate?sl=es&tl=en&js=n&prev=_t&hl=es&ie=UTF-8&u=http%3A%2F%2Fwww.cherada.com%2Farticulos%2Ffch93-s316-p25259-doctor-viktor-bokov-se-avecina-una-nueva-glaciacion-en-la-tierra
Extract:
“3.-You said in my book in 2005 Glacial Heat expected cooling or ice would start with the new solar cycle from 2010-2012, according to the meteorological index Vangengeim-Girs, do you still think the same?
Yes, start with the 2012-2015 cooling and indirectly be connected with the new solar cycle 24 (which has been advanced in January 2008). The influence of the Sun in time and climate of the Earth is shown through the transformations of the forms of atmospheric circulation that influence a condition of the world ocean with subsequent interference of the ocean and atmosphere. In connection with the prevalence of any form of flow paths cyclones (low pressure = bad weather) and anticyclones (high pressure = good time) vary warming causes an area of global warming and a cold snap in another .
Transforming atmospheric turbulence trajectories atmospheric conditions change in different areas of the Earth. These paths are maintained from 10 to 40 and then alter the subsequent return. The expected increase in the repeatability of the southern forms Circulation Vangengeim-Girs C will lead to a cold snap similar to what was observed in the XVII and XVIII (there was a mini ice age known as the Maunder Minimum.
But cooling does not begin abruptly but gradually slow growth in the number of snow and cold winters. Increased catastrophic natural phenomena is observed in a time interval when the circulation forms W and C and E are close to equal amount of repeatability. Well be seen in figure 1, which shows the forms W, C and E in the last thousand years reconstructed by myself. “
TimTheToolMan says:
October 13, 2013 at 3:36 pm
So for example the amount of UV in recent solar cycles may on average be a little higher (or lower) than in the past.
No, we know that is not the case. I assume that you mean for cycles of equal strength, otherwise your comment has no meaning. And since we know the UV flux and the sunspot number back 170 years, we can check if you assertion is true and it isn’t.
tumetuestumefaisdubien1 says:
October 13, 2013 at 5:16 pm
First, as you surely know the causal relation between sunspots and TSI is negative – sunspot occurrence on the disk causes TSI to drop – their correlation is typical example of correlation which has nothing to do with causation, because the factor – solar activity – which makes them correlate is independent from the two.
No, there is a strong causation: Magnetic fields are born as faculae, evolve into sunspots, which in turn evolve into faculae. Faculae brighten the Sun twice as much as sunspots darken the sun, and the faculae and spots vary closely together.
as that UV [and therefore TSI] varies “just as the sunspot number”, it is mathematically ruled out straight away.
Regardless, observations show that UV and sunspot number vary the same way.
It seems to show, that generally the relative variability in UV region rises steeply with frequency
So what? the UV is still the same fraction of solar activity, because UV varies closely with the sunspot number.
which in some regions seem even show quite strong antiphase behavior. …
People have looked at this and find effects of the order of 0.05C, so completely negligible.
The rest of your comment is just speculation and hand waving, granted that hand waving is the most common wave in all of climate science.
TimTheToolMan says:
October 13, 2013 at 3:36 pm
tumetuestumefaisdubien1 says:
October 13, 2013 at 5:16 pm
For both of you: http://www.iup.uni-bremen.de/gome/gomemgii.html
lsvalgaard says:
October 13, 2013 at 7:16 pm
“People have looked at this and find effects of the order of 0.05C, so completely negligible. The rest of your comment is just speculation and hand waving, granted that hand waving is the most common wave in all of climate science.”
So in your opinion the well established facts that 1: the ocean receives very considerably more effective insolation than is the Earth average (both because the bulk is at lower latitudes then the latitude of average insolation, and due to way lower than average Earth surface reflectivity), that 2: ocean water simply doesn’t have ε=1 or very close to 1, that 3: atmospheric water content very strongly absorbs IR around 1125nm, 1375nm and 1875nm bands (and I would add that in the >1 micrometer region of solar spectrum has very often several orders of magnitude higher absorbtivity than for UVA+B region – which by far cannot be ofsetted by the O3 atmospheric content when we talk about surface solar irradiance variability, not speaking that both contribute each at its point of occurence to atmospheric temperature, which is crucial factor directly determining radiative heat transfer rate from surface to space) is “speculation, handwaving”?
I’ll tell you something Leif: just the first 2 points from the 3 I’ve just named would cut the above 3.6 factor figure you liked so much (well, I suspect because it so well seems to confirm your well known bias) by factor >2.
How much the highly diverse and sometimes maybe even paradox SSI variabilities in various spectral regions of the solar spectrum (which seems the SORCE SSI now shows, and generally higher than thought until now) relatively to the TSI variability would contribute to the temperature changes I don’t well know, but it is you who names it (“order of 0.05C” – “completely negligible”), thank you. – It seems like you still haven’t noticed it, but nothing more than the 0.04-0.05C solar cycle SST amplitude and what&how causes it this whole debate is about. (ROFLMAO smiley)
tumetuestumefaisdubien1 says:
October 14, 2013 at 2:49 am
So in your opinion the well established facts…
A collection of facts of facts is one thing, the attempted conclusion drawn from that is something else. That is the hand waving comes in.
How much the highly diverse and sometimes maybe even paradox SSI variabilities in various spectral regions of the solar spectrum (which seems the SORCE SSI now shows, and generally higher than thought until now) relatively to the TSI variability would contribute to the temperature changes I don’t well know, but it is you who names it (“order of 0.05C” – “completely negligible”), thank you. – It seems like you still haven’t noticed it, but nothing more than the 0.04-0.05C solar cycle SST amplitude and what&how causes it this whole debate is about.
As I said, people have looked into this, e.g. see http://lasp.colorado.edu/sorce/news/2011ScienceMeeting/docs/presentations/6b_Cahalan_Sedona_9-15-2011.pdf and if all the Sun is doing is 0.05C then the Sun is not a major driver of climate, which is really what this whole debate is about.
Steven Mosher says:
October 10, 2013 at 10:14 pm
Do you seriously imagine that modelers know all the sources of climate forcings? Or that the assumptions they make about each even remotely correspond to reality?
Clearly, they don’t, since the GCMs fail so ludicrously epically.
milodonharlani says:
October 12, 2013 at 5:39 pm
Jim G says:
October 12, 2013 at 5:30 pm
Here’s an explanation for why there was so much thermal expansion in the Cretaceous:
http://serc.carleton.edu/research_education/cretaceous/superplume.html
I see a lot of confusion on this thread between energy and power. Power is the time flux of energy. TSI is a measure of areal density of power. It has units of Watts/m^2. A Watt is a Joule per second. A Joule is a measurement of energy.
It makes no sense to say that TSI does not provide enough energy to effect some temperature variation. TSI is continuously providing energy, some number of Joules per square meter per second. Over time, those Joules can accumulate. A small variation in Watts can integrate over a long period of time into a significant number of Joules.
I thought that it was understood that the integration time was the solar cycle period.
Bart says:
October 14, 2013 at 10:02 am
I see a lot of confusion on this thread between energy and power.
In this case the confusion is in the eye of the beholder.
It makes no sense to say that TSI does not provide enough energy to effect some temperature variation.
In that case it makes no sense to say “TSI is continuously providing energy”
Over time, those Joules can accumulate.
When you heat something up, it will immediately radiate the energy absorbed away, unless you provide isolation to keep it from radiating.
bones says:
October 14, 2013 at 10:19 am
I thought that it was understood that the integration time was the solar cycle period.
Why that?
“When you heat something up, it will immediately radiate the energy absorbed away, unless you provide isolation to keep it from radiating.”
Ah, so that’s why, when I put a pot of stew on the stove, it heats up immediately and then resumes room temperature as soon as I turn off the eye. I really think you enjoy disagreeing just to be disagreeable.
bones says:
October 14, 2013 at 10:19 am
“I thought that it was understood that the integration time was the solar cycle period.”
The “solar cycle” is only one component of TSI variation. Other components of longer duration have more time to integrate into something of significance.
Bart says:
October 14, 2013 at 11:20 am
“When you heat something up, it will immediately radiate the energy absorbed away, unless you provide isolation to keep it from radiating.”
Ah, so that’s why, when I put a pot of stew on the stove, it heats up immediately and then resumes room temperature as soon as I turn off the eye. I really think you enjoy disagreeing just to be disagreeable.
To reduce your confusion I probably should have said: “it will immediately begin to radiate…”, although I took that as going without saying, but, of course, it is dangerous to make assumptions about people’s abilities [so sorry about that].
The “sunspot time integral” and ocean oscillations explain 90-96% of observed global temperature variability
http://hockeyschtick.blogspot.com/2010/01/climate-modeling-ocean-oscillations.html
http://hockeyschtick.blogspot.com/2013/08/natural-climate-change-has-been-hiding.html
lsvalgaard says:
October 14, 2013 at 11:29 am
‘To reduce your confusion I probably should have said: “it will immediately begin to radiate…”’
Which renders your previous statement meaningless.
I’m not getting into this with you today, Leif. I have provided some contextual info for people to consider. That was my purpose, and I am done.
Bart says:
October 14, 2013 at 11:25 am
The “solar cycle” is only one component of TSI variation. Other components of longer duration have more time to integrate into something of significance.
What other components? The solar cycle itself varies with time [and with it TSI, UV, GCRs and all the rest], so what other components are there?
Hockey Schtick says:
October 14, 2013 at 11:31 am
The “sunspot time integral” and ocean oscillations explain 90-96% of observed global temperature variability
We have discussed this before. The fit uses a circular argument. Good to see that you admit there is something woolly about it by put the sunspot integral in quotes.
Bart says:
October 14, 2013 at 11:32 am
I have provided some contextual info for people to consider. That was my purpose, and I am done.
I don’t think anybody here was confused, except possibly yourself when you say that “TSI is continuously providing energy”. TSI is a measure of power [expressed as power density over 1 square meter], not of energy.
The fit uses a circular argument. Good to see that you admit there is something woolly about it by put the sunspot integral in quotes.
Don’t put words in my mouth. The only reason for the quotes is a shorthand way of referring to the accumulated departure in sunspots v. the monthly mean of 41.2 for the observational period of sunspots 1610-2009.
What do you specifically claim is a circular argument?
Hockey Schtick says:
October 14, 2013 at 2:04 pm
What do you specifically claim is a circular argument?
not ‘claim’, just telling. The fit already injects temperature dependent data. But you should know that best. Here is the sunspot integral over the time where we have reasonable data http://www.leif.org/research/SSN-Integral.png
This does not fit ‘almost perfectly’ as your link claims.
Hi I stumbled on this post and decided to address two points.
First, I saw that Overholt 2009 was mentioned as something refuting my work (together with Jan Veizer):
“It has already been shown by Overholt et al (2009) that the peaks and troughs in the Shaviv distribution do not correspond to crossings of the SA in the Galaxy. Here we show that the estimated intensity variations from the Shaviv distribution are also unrealistic”,
Well, it should be mentioned that their whole analysis has a major flaw. Instead of calculating the spiral arm passage with the relative pattern speed, they use the absolute pattern speed and don’t account for the rotation of the sun! It is that stupid! I wrote those guys, and they eventually published an erratum ( http://adsabs.harvard.edu/abs/2012ApJ…751L..45O ), but still claimed that their paper proves my analysis with Jan to be wrong. In fact they don’t because they take an unrealistically distorted spiral arm structure. They cannot admit that they are wrong to save face I guess.
The second point has to do with measuring the solar forcing. Because the climate acts as a low pass filter, the temperature response over the 11-year solar cycle is highly damped. This is why it is hard to infer a climate sensitivity from it (I didn’t appreciate this point when I wrote the sensitivity paper in 2005). However, for the same reason, the 11-year solar cycle is actually fantastic to measure the radiative forcing, because the climate system can barely respond to the varying forcing, which means that the oceans lose only a little amount of heat and they can be used as a calorimeter with a high efficiency (though not perfect). The bottom line in that analysis (from 2008) is that the solar forcing is about 1 W/m^2 over the solar cycle, not 0.17W/m^2 as satellites measure. Of course, the IPCC does not even mention this paper since it wasn’t refuted by anyone and its conclusions are very inconvenient for them…