Total solar irradiance, also called “TSI”, is the total amount of energy coming from the sun at all frequencies. It is measured in watts per square metre (W/m2). Lots of folks claim that the small ~ 11-year variations in TSI are amplified by some unspecified mechanism, and thus these small changes in TSI make an observable difference in some aspect of the temperature.
In that regard, here are the monthly variations in TSI (as a global 24/7 average) as shown by the CERES data:
Figure 1. Variations in TSI. The upper panel (red) shows the actual measured TSI. The middle panel shows the seasonal component of that variation. The bottom panel shows the ~ eleven-year variation in TSI once the seasonal data has been removed.
There are oddities in this record. Overall, the ~ eleven-year variation is a bit more than a quarter of a W/m2. However, from late 2000 to early 2001, the TSI dropped a bit more than a quarter of a W/m2. However, I digress …
My question is, if the tiny eleven-year changes in TSI of a quarter of a W/m2 cause an observable change in the temperature, then where is the effect of the ~ 22 W/m2 annual variation in the amount of sun hitting the earth? That annual change is a hundred times the size of the eleven-year TSI change. Where is the effect of that 22 W/m2 change?
To get an idea of the predicted effect of this variation in TSI, using IPCC figures this TSI change of 22 W/m2 is about the same change in forcing that we would get from six doublings of CO2 … that is to say, CO2 going from the current level (400 ppmv) to the extraordinary level of 25,600 ppmv.
In addition, again according to the IPCC, using their central value of 3°C warming per doubling of CO2 (3.7 W/m2 additional forcing), this change in forcing should be accompanied by a change in temperature of no less than 18°C (32°F).
Now, I can accept that this would be somewhat reduced because of the thermal lag of the climate system. But the transient (immediate) climate response to increased forcing is said to be on the order of 2°C per doubling of CO2. So this still should result in a warming of 12°C (22°F) … and we see nothing of the sort.
I say this lack of an effect of the TSI changes is because the climate system responds to the current conditions. The climate system is not some inanimate object that is simply pushed around by external forcings. Instead, it reacts, it responds, it evolves and varies based on the instantaneous local situations everywhere. In particular, when it is cold we get less tropical clouds, and that increases the energy entering the system. And similarly, when it is warm we get more tropical clouds, cutting out huge amounts of incoming energy by reflecting it back to space. In this way, the system reacts to maintain the same temperature despite the changes in forcing.
However, I’m happy to listen to alternate explanations and to consider opposing evidence … so if you think that the IPCC is right when it says that changes in temperature are driven by the changes in forcing, I ask you why the annual forcing change of 22 W/m2 doesn’t seem to show a corresponding 12°C change in global temperature.
Best to everyone,
w.
My Request—if you disagree with someone, please quote the exact words you disagree with. This allows us all to understand just what you think is incorrect.
What the Earth reacting to solar irradiance may look like:
http://www.srh.noaa.gov/jetstream/tropics/images/itcz.jpg
https://en.wikipedia.org/wiki/Intertropical_Convergence_Zone
The ITCZ (aka the doldrums) has been known about for a long time, see below:
Day after day, day after day,
We stuck, nor breath nor motion;
As idle as a painted ship
Upon a painted ocean.
FROM:
The Rime of the Ancient Mariner
Samuel Taylor Coleridge (originally published in Lyrical Ballads, 1798)
I am mystified as to how your link to the ITCZ fits with small changes in TSI – the subject of this post by Willis.
The ITCZ is an example of the Earth responding quickly to solar radiation. Whether there is a sensitivity to small changes is not known, but there definitely are mechanisms which respond to the minor variation of the Sun’s apparent path across the surface.
“The climate system is not some inanimate object that is simply pushed around by external forcings. Instead, it reacts, it responds, it evolves and varies based on the instantaneous local situations everywhere.”
Isnt this passage in reference to the ” horse latitudes, not the Itcz?. The area where the subtropical high resides with lack of wind, well north of the ITCZ
The Horse Latitudes (30 to 35 degrees N & S) lie well to the north & south of the ITCZ, which, as its name implies, lies in the tropics. However, the ITCZ does partially coincide with the doldrums, the band of frequent calms. But the trade winds subside again in the higher Horse Latitudes, so the “The Rime of the Ancient Mariner” could have applied to either band of still air over the world’s oceans.
Nevertheless AnonyMoose’s point about the effect of sunshine on ocean & air is well taken.
As I recall – it has been long since I read of this – Coleridge heard the tale while in an East coast port (Boston?), and the voyage was to San Francisco. He was not on the ship. These lines suggest the person telling the tale knew of what he spoke:
“And ice, mast-high, came floating by,
As green as emerald.”
—————————
Anyway . . .
They sail southward in the Atlantic Ocean
In Part 1, “The sun came up upon the left,”
They pass the tip of South America:
“And now there came both mist and snow,
And it grew wondrous cold:
And ice, mast-high, came floating by,
As green as emerald.”
Part 2 starts:
“The sun now rose upon the right:”
So now they are heading northward along the west coast of SA.
The South Pacific High is there to the west, and near the coast the Humboldt Current.
In this part there are these 4 lines:
“All in a hot and copper sky,
The bloody sun, at noon,
Right up above the mast did stand,
No bigger than the moon.”
If the ship is in the South Pacific High,
with the sun, at noon, above the mast, this would make the month December or January, maybe. Could be.
In March or September the ship would have to be nearer the Equator.
My thought was that a captain would stay closer to the coast, heading north.
The reasoning is that by these times, the locations of the STHP and the currents were widely known. They would try to stay away from the high pressure.
But, sometimes the trades do not meet and this would be much harder to predict or maybe even know about:
“We were the first that ever burst
Into that silent sea.”
Willis is a seaman. Maybe he has a better idea of this than I do.
I believe that in the next 5 – 10 years CO2-climate change hysteria will finally be put to rest and it will be written about its purveyors thusly:
He went, like one that hath been stunn’d
And is of sense forlorn:
A sadder and a wiser man
He rose the morrow morn.
I don’t understand the seasonal TSI plot. The Earth’s aphelion is 152.1×10^6 km, and it’s perihelion is 147.09×10^6 km. The intensity of sunlight varies inversely as the square of the distance, so the ratio of irradiance from aphelion to perihelion will be (Rap/Rperi)^2 = (152.1/147.09)^2 = 1.069. If TSI = 1300 W/m^2 at perihelion, it will be 1390 W/m^2 at aphelion. That’s a 90 W/m^2 change, not a 21 W/m^2 change. It almost seems like you took the square root of the ratio of the orbital radii, which would give 21 W/m^2 swing. Am I wrong about this?
I had aphelion and perihelion reversed in my example, sorry. The ratio is still correct.
Perhaps it’s because virtually all of that radiation is coming in at an oblique angle? Outside of a small circular area in the center of the Sun-facing hemisphere, the incoming radiation is being spread across a larger and larger area, until the angle becomes tangential and parallels the surface of the Earth.
I’m terrible at math, but I’d imagine that’s why the TSI is lower than a simple area calculation would indicate- it’s striking a three-dimensional, increasingly-inclined surface.
Not just one amplification mechanism, & far from being “unspecified”, they have been discussed highly specifically.
http://www.climatechangedispatch.com/new-paper-finds-multiple-solar-amplification-mechanisms-which-modulate-winter-surface-temperatures.html
But more importantly, TSI is less important to climate than its energetic UV component, which fluctuates by orders of magnitude more than TSI, & than solar magnetic effects.
How many W/m2 of total TSI is caused by the “energetic UV component”? Even if the entire change in TSI was attributed to the “energetic UV component” how much would that be in actual W/m2?
http://astro.ic.ac.uk/research/solar-irradiance-variation
http://en.wikipedia.org/wiki/Sunlight#mediaviewer/File:Solar_spectrum_en.svg
http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=10&ved=0CEwQFjAJ&url=http%3A%2F%2Fsolar.physics.montana.edu%2FSVECSE2008%2Fpdf%2Fwoods_svecse.pdf&ei=-2NMVNqQIZC6iQLUnYGAAg&usg=AFQjCNEaTydUjU_L7OZVEQQiFMs6d4wztQ&sig2=fWv8W2dRw_LNIx8SlK_obQ&bvm=bv.77880786,d.cGE
Page 4 in the last link compares variation in TSI with UV.
The energetic UV makes up 0.00005 of TSI, not much in terms of energy.
Here is how the EUV has varied the past 174 years
http://www.leif.org/research/Reconstruction-Solar-EUV-Flux.pdf and put in a wider perspective
http://www.leif.org/research/Keynote-SCOSTEP-2014.pdf
Hard to believe that there is any measurable climate connection
Total UV, not just its most energetic band, makes up more, as you know, & all UV is energetic compared to visible & IR spectra.
But it’s not the share of TSI that is UVa, UVb or UVc that matters, but the effect of UV on ozone & oceans that does.
And yet, when you want to show the variation of UV you show the EUV [Figure 4 of your last link] so you speak with a forked tongue [it seems that anything goes when it is about convincing the unwashed masses].
I would have shown total UV, but was responding to a specific request for information about energetic UV.
My tongue is unified, as the two other links show. Just aiming to oblige.
Since the variation of UV is due to the same agent [the magnetic field] that causes the variation of TSI, the UV and TSI vary together in lockstep, and the variation of TSI and EUV over the past 174 years does not follow the variation of climate. Even a unified tongue can wag nonsense [even if it is a firm belief, to which the data will have to submit]. I think it is better to follow the data and admit that the belief is unwarranted.
On the contrary, I find the correlation between UV & magnetism, on the one hand, & climate, on the other, to be so statistically strong, that causation is not only implied but inescapable. Somehow you have managed to let it escape.
For magnetism & climatic correlation, please see SSN minima & the Little Ice Age.
Spoken as a true believer. Nothing can rock your boat.
I find the true belief on your side. For whatever reason, you can’t see the sun shining on the forest for the shade of the trees.
I give you more credit than hopping on the CACA gravy train. When my friends in Congress ask where to cut in science, I never suggest solar research, even though a lot of it has become corrupted & polluted by the CACA virus.
How anyone can d*ny the influence of solar activity on climate is beyond me, but I attribute ulterior motives only to those who don’t practice the scientific method, as I feel you try to do.
The reason is simple: there is no good evidence for such a connection. Lots of claims, but none of them hold up according to my standards. You bar is much lower, evidently.
Here is one of the reasons I don’t see what you ‘see’:
http://www.leif.org/research/EUV-and-Global-Temps.png
Milodonharlani:
You had best pay attention to Leif, who only wants to remedy your crackpot theories. We all wish to help, you see.
milodonharlani
October 25, 2014 at 8:10 pm
“Page 4 in the last link compares variation in TSI with UV.”
————————————————————————————————————————–
But the scales are different. The TSI is labeled W m-2 and the UV is labeled mW m2. Explain please.
milodonharlani
October 25, 2014 at 9:57 pm
“I would have shown total UV, but was responding to a specific request for information about energetic UV.”
————————————————————————————————————————-
I asked it that way because it was how YOU addressed it here:
milodonharlani
October 25, 2014 at 6:53 pm
“But more importantly, TSI is less important to climate than its energetic UV component, which fluctuates by orders of magnitude more than TSI, & than solar magnetic effects.”
mpainter
October 26, 2014 at 3:22 am
Which theories do you imagine are crackpot?
I know that you adhere to the counterfactual crackpot belief that the Central American Seaway was closed by 10 million years ago & that warm currents only flow poleward, contrary to all available evidence from biology, geology & oceanography. Have you checked up on the direction of the equatorial currents yet?
Please state which “theories” of mine you consider crackpot. Is it that the variation in UV & solar magnetism affect climatically important phenomena, such as ozone production, seawater temperature & GCR flux? Too bad for you, because those effects have been observed in nature & confirmed experimentally.
Please state which “theories” of mine you consider crackpot. Is it that the variation in UV & solar magnetism affect climatically important phenomena, such as ozone production, seawater temperature & GCR flux?
Ozone and GCR flux, yes, but there is no evidence for seawater temperature variation following solar magnetism.
Not only that, but the thickness of the ionosphere varies considerably with incoming UV: the range of thickness is typically from 200 to 500 km (diurnal variation) and from 50 to 2000 km over a solar cycle. This approaches two orders of magnitude variation.
Although the density of the ionosphere is quite low, it is thick enough that a photon can’t pierce it without collision with at least one molecule or ion. The result may be equivalent to a change in the black body temperature of the sky or its optical density.
milodonharlani says: October 25, 2014 at 6:53 pm
I subscribe to this line of thinking. And I feel like people dismiss it or act like they do not know about it, so they can refrain from having to say, it could be worth exploring. It took about a dozen posts for me to get to the point where Willis admitted he knew what I was saying was correct, when I said the UV components changes substantially. He tried to say it changed by a fraction of a percent, but then went silent. I will find the posts if Willis would like to respond. But it’s quite a mess of posts.
Anyway – we all agree that UV changes substantially now, so I will not need to waste a dozen posts going around in circles. And yes – I am not a scientist and yes I have not put forth the study – I just subscribe to the ideas I read and think they are valid hypotheses to be explored.
Mario Lento October 26, 2014 at 1:44 am
Mario, please do come up with the link, because I have no recollection of you writing a dozen posts before I responded … and it does change by only a fraction of a percent.
I know that the EUV changes AS A PERCENTAGE more than does the TSI, and have known that for years. However, what you and milodon never have seemed to have noticed is that is simply because the TSI varies so little in both energy and percentage terms.
AS A PERCENTAGE, the EUV, as you point out, varies about 10 times more than the TSI. Which sounds impressive until you realize that the TSI itself only varies peak-to-peak by about one part in 1,360, which is about seven-HUNDREDTHS of a percent. So you are right that the EUV varies ten times as much as TSI AS A PERCENTAGE—which means it varies by a whopping seven-TENTHS of a percent … not even one percent.
AS ENERGY, the EUV only represents about 1% of the total energy of the TSI, or about 14 W/m2. A change of 0.7% in that is a change of about one-TENTH of a watt per square meter.
So the EUV is changing by about seven-tenths of a percent, or alternately about a tenth of a watt per square metre, over the eleven-year sunspot cycle. Regarding those changes, you say:
No, we don’t agree at all. Whether we look at seven-tenths of a percent, or one tenth of a watt per square metre, neither one is a “substantial” change unless you are using some bizarre meaning of “substantial”.
But clearly, you believe that fraction of a percent|watt makes some huge difference in the earth’s climate … if so, perhaps you could show us the evidence for your belief.
And while you are at it, as I show above, the TSI varies by 22 W/m2 over the course of the year. This means that the EUV is varying as well, by about the same amount (as a percentage). If EUV is so critical, where is the evidence for your claimed effect from that huge variation in EUV?
Best regards,
w.
milodonharlani, the V. Maliniemi, T. Asikainen and K. Mursula paper you quoted says the clearest signal for a positive NAO is in the declining phase of the solar cycle, that’s during the typical maximum of the solar wind speed. There is also a clear signal for negative NAO at the local minimum in the solar wind speed a year or so after each sunspot cycle minimum. There can also be a major minima in the solar wind speed at sunspot maxima, but not on every occasion, it was largely absent in solar cycles 22 and 23.
Ulrich,
A number of studies have found a correlation between solar eruptions & solar wind speed & the NAO & the ENSO. To cite but a few.
http://www.john-daly.com/theodor/solarnao.htm
http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=2&ved=0CDkQFjAB&url=http%3A%2F%2Fwww.issibern.ch%2Fteams%2Finterplanetarydisturb%2Fwp-content%2Fuploads%2F2014%2F04%2FAsenovski_03_2014.pdf&ei=FXpNVJTcDtH6oQSerIHACw&usg=AFQjCNFRsOQtVJbZiK_8MHWiZbcFDLeTuQ&sig2=m8j6RL2KQ5AxGQ7hlpM3kA&bvm=bv.77880786,d.cGU
http://onlinelibrary.wiley.com/doi/10.1029/2002GL014903/full
http://adsabs.harvard.edu/abs/2014SunGe…8…97A
(Available in a .pdf if this link doesn’t work.)
http://www.researchgate.net/publication/228574599_Solar_wind_electric_field_modulation_of_the_NAO_A_correlation_analysis_in_the_lower_atmosphere
Thanks for noticing & commenting upon that correlation between a climatic phenomenon & solar activity.
PS: Perhaps no accident that the end of the approximate end of the LIA coincides with the Carrington Event.
http://www.solarstorms.org/SS1859.html
It is a mistake to assume that the mechanism of solar effect on temperature must be TSI. At some frequencies solar emissions vary by huge percentages over 11 year cycle. These might act on earth environment to allow other radiation to get through our not.
“Total solar irradiance, also called “TSI”, is the total amount of energy coming from the sun at all frequencies. It is measured in watts per square metre (W/m2). Lots of folks claim that the small ~ 11-year variations in TSI are amplified by some unspecified mechanism, and thus these small changes in TSI make an observable difference in some aspect of the temperature.”
I don’t think it is ALL Frquencies but I could be wrong.
https://tallbloke.wordpress.com/2012/11/22/tim-cullen-the-problem-with-tsi-total-solar-irradiance/
This link is GREAT! Thanks for it.
WILLIS! Have you read this? If not, do so. What do you think about it. Inquiring minds want to know. Thanks.
Michael Wassil October 25, 2014 at 8:17 pm
Thanks, Michael. See Leif’s (lsvalgaard) response above. We have lots of information about TSI from a number of platforms.
In addition, the main graph in the link you cited is a Wikipedia graph from an anonymous poster, with absolutely no information about the source of the information … Michael, I strongly and emphatically recommend against using Wikipedia for ANYTHING involving climate, including solar. There is more misinformation there than anyone could possibly sort out, and the provenance of the graphics is often non-existent, as in this case.
Finally, even assuming the graph were correct, all that would mean is that the sun is not radiating like a theoretical black-body … a theoretical black-body which is all at one single precise unchanging temperature all over the surface, a black-body that is not losing energy via ejections of mass from the surface and via a varying electromagnetic field, a black-body that is not varying over an 11-year cycle with different frequencies showing different variations, a black-body that is all rotating at the same speed …
Yes, the sun doesn’t radiate like a theoretical blackbody… so what? Did you really expect the immensely complex sun to behave exactly like a single-temperature theoretical black body?
Regards,
w.
You are wrong.
More precisely: Apart from Cullen’s nonsense about the atmosphere at 645 km height is ‘transforming’ TSI, TSI is also measured by the PMO6V and Diarad experiments on SOHO, about a million miles above the Earth’s surface
http://www.pmodwrc.ch/pmod.php?topic=tsi/virgo/proj_space_virgo
Willis, where does your 22w/m2 annual variation come from?
Asymmetry of the earth’s orbit – closer to the sun during the northern hemisphere winter / southern hemisphere summer means asymmetric TSI / non-constant / cyclic TSI of the solar year, Right Willis ?
Given the lags in the climate system, it does beg the question of just how “instantaneous” TCR is when compared to ECS; perhaps ECS is more of a figment of climate modeling imagination than something real, given that we don’t see the big variations in annual mean global temps as W points out (for that matter, we don’t see any systematic variations in annual temps correlated to annual variations in TSI).
Orbital insolation changes balance out over the entire planet.
Curious that the earth’s atmosphere cools during this much more intense SH summer insolation. Yes, the NH does reflect more sun light during its winter, and as a whole the earth reflects more sun light. But the SH oceans absorb much of this increase in surface insolation, preventing said insolation from reaching the atmosphere, at least preventing said insolation from reaching the atmosphere right away.
Willis makes an excellent observation about how dynamic the earth is, and this seasonal response is an excellent example. Yet the question remains, is the earth gaining or losing energy when the atmosphere cools during the SH summer? I am guessing that it is gaining energy, but I have not seen this quantified.
Because of the oceans capacity to absorb energy I do not discount how a small change in TSI can, over TIME, add up to a substantial amount of energy which could ultimately manifest in an increase in atmospheric GAT, There are only two ways to change the temperature of a system in a radiative balance. One is to change the input. The other is to change some aspect of the residence time of energy within the system. A small flame under a large open pot of water can only arm that pot a little. However place a small flame under the center of a large open pot while thinning the center portion, and increasing the thickness of the rest of the pot, and placing a lid on top of the pot, and the small flame can, over time, boil the water. The only thing that changed was the residence time of the energy within the pot.
Just as the earth masks the annual immense change in seasonal insolation, so might it mask the decadal change in TSI, with a small increase in insolation entering the oceans, accumulating daily for years, perhaps decades. Other specify that this TOA change in insolation could affect cloud formation and jet stream location, greatly amplifying the initial change in TSI. (I see no great support yet for their theories, but, in light of the planets capacity to mask an immense seasonal change in TSI, I certainly do not yet discount them.) Also their are many mysteries about Jet stream patterns and cloud formation. Science is never closed minded. Scientist can be equally closed minded about not accepting criticism of a theory, and about not being open minded to understanding in areas poorly understood. As their are numerous peer reviewed papers discussing and attributing climatic impacts due to solar changes, it is an area IMV for science to continue to explore.
It does not shock me that no one factor shows a consistent affect on the earth’s atmosphere GAT. There are so many competing influences, some short term, some medium term, some seasonal, some decadal, some centurion, and some millennial. IMV only when an adequate number of disparate climate factors align do we get a substantial change in GAT. (The oceans varying release of energy, ENSO factors, as outlined by Bob Tisdale, are the closest thing that I have seen to showing a consistent affect on the earth’s GAT) However the atmosphere is the tail, not the dog. The atmosphere warming from an oceanic release of energy at the surface, could, and often does mean a cooling planet.
the annual 90 W/m2 divided by 4 to account for the Earth being round and that one half of the Earth receives no sunlight.
Given that the NH winter is at aphelion, it receives both substantially more insolation and less duration of winter (several days less because of the shorter orbit path length) than the SH winter. Damn good reason that global warming has been more pronounced in the NH. True or false?
One would think so, but the minute solar signal seems to be drowned in the noise.
So when the numbers were published that incoming was 363 w/m^2 and retained was 240 w/m^2, was that divided by 4 also, or was that only on the sun side? I’m curious to know what those numbers are now per the IPCC. Especially in light of how much more co2 has been put into the atmosphere. You are going to have a problem no matter what, that’s why it’s not published, n’est pas?
Interesting read . Thanks for that!
Strangely like a healing process reaction………
Could clouds be like platelets in some way?
Hummmmm
” I ask you why the annual forcing change of 22 W/m2 doesn’t seem to show a corresponding 12°C change in global temperature.”
Dunno, Willis, but THE SCIENCE IS SETTLED!
So no more pesky questions, ok?
(ps – I enjoyed your recent sea voyage log. I was staying on Vancouver Is at the same time, so I could really relate to the superb weather, etc. When can we enjoy your next travelogue?)
“In this way, the system reacts to maintain the same temperature despite the changes in forcing. However, I’m happy to listen to alternate explanations and to consider opposing evidence”
I would suggest the reason is that the thermodynamics of convection, evaporation, adiabatic lapse rate/pressure/atmospheric mass/gravity dominate the troposphere and “short-circuit” most of the radiative forcing, as shown in fig 4 of this paper describing radiative-convective equilibrium in planetary atmospheres:
http://4.bp.blogspot.com/-4ztu-bAVH4M/UxTWMT_c0iI/AAAAAAAAFzo/1vvqCmqWFBI/s1600/circuit+analogy.jpg
http://www.lpl.arizona.edu/~rlorenz/convection.pdf
also subsequently demonstrated by a paper in Nature by Robinson & Catling to apply to all planets with thick atmospheres in our solar system:
http://faculty.washington.edu/dcatling/Robinson2014_0.1bar_Tropopause.pdf
one of several posts describing the Robinson & Catling paper at diggingintheclay.wordpress.com:
http://diggingintheclay.wordpress.com/2014/04/27/robinson-and-catling-model-closely-matches-data-for-titans-atmosphere/
i.e. convection dominates over radiative forcing in the troposphere until the atmosphere becomes too thin to sustain convection at P=0.1 bar, i.e. where the tropopause begins and radiative forcing takes over.
Above I cited this from an August 2014 post on the Hockey Schtick:
http://hockeyschtick.blogspot.com/2014/08/new-paper-finds-multiple-solar.html
The amplifying mechanisms it mentions are of course not all inclusive.
Thanks.
Tell your author of that paper to not bother applying to me for a job as a circuit engineer.
It’s simply an explanatory analogy to radiative-convective equilibrium, from an astrophysicist, and not an electronic engineering paper obviously. Care to enlighten what is wrong with the simple analogy, I.e. If Rc < Rt wouldn't Rc "short-circuit" Rt?
It’s close enough for climate science.
Getting wannabe climate scientists to recognize that moist convection outstrips not only radiation, but all other mechanisms combined in transferring energy from surface to the troposphere remains one of the great challenges of blog discussion.
1sky1 October 27, 2014 at 1:19 pm
Citation? The Kiehl/Trenberth budget has it as follows;
and the CERES data basically agrees, giving the following figures:
Total of sensible and latent heat loss (moist convection) = 109 W/m2 (K/T says 97 W/m2)
Upwelling radiation 398 W/m2 (K/T says 396 W/m2)
In other words, both of them say that radiation is the largest way that the surface loses energy, with moist convection coming in second and sensible heat loss (dry convection) third largest.
Regards,
w.
The dominance of moist convection over other mechanisms of heat transfer
from the surface is well-known among energy-budget experimentalists. In
all but the driest, coldest environments, measurements usually show that
the ratio of sensible-to-latent heat transfer (the Bowen ratio) is <1. A
serviceable introduction to actual surface energy budgets is provided by
http://www.atmos.washington.edu/~dennis/321/321_Lecture_14.pdf.
The K&T cartoon tends to obscure these empirical facts by showing large
oppositely directed radiative fluxes, indicative of radiative EXCHANGE at
high surface temperature, rather than actual heat TRANSFER in the system.
In fact, even by K&T's account, the NET radiative transfer is quite small
(63W/m^2) and appreciably less than that attributed to moist convection.
Serious physical treatises (e.g., Peixoto and Oort) do not indulge in such
misleading presentations, which have led many into grossly distorted notions
of the importance of radiative transfer in affecting surface temperatures.
Oooh, 1sky1, now you are changing the goal posts, no points for that.
You originally discussed:
Now you want to change that entirely, and you want to include transferring energy TO the surface FROM the troposphere.
Sorry, I don’t play those kind of games. If you wanted to discuss transfers from the atmosphere to the surface, you should have said so.
Better luck next time, but don’t expect to get an answer from me next time. Your kind of BS doesn’t fly on my planet, you just wasted my time entirely. Don’t worry … won’t happen again.
w.
Huh??? FYI, thermal-energy transfer is always UNIDIRECTIONAL, from warmer to colder body. It necessarily takes into account radiative fluxes in ALL directions. Unlike those locally variable, intensive fluxes, it is a conservative, extensive metric. Only someone bereft of any scientific scientific sense of the term “heat transfer” would indulge in the face-saving pretense of “changing the goal posts.”
1sky1 4:19pm: “FYI, thermal-energy transfer is always UNIDIRECTIONAL, from warmer to colder body.”
Not according to Dr. Max Planck – from his experiments radiative energy transfers bidirectional meaning both ways between bodies such as atm., earth L&O and deep space sink:
“A body A at 100C emits toward a body B at 0C exactly the same amount of radiation as toward an equally large and similarly situated body B’ at 1000C. The fact that the body A is cooled by B and heated by B’ is due entirely to the fact that B is a weaker, B’ a stronger emitter than A.”
Page 9, paragraph 7 here:
http://www.gutenberg.org/ebooks/40030?msg=welcome_stranger
******
4:50pm: “In fact, even by K&T’s account, the NET radiative transfer is quite small (63W/m^2) and appreciably less than that attributed to moist convection.”
The net from bidirectional radiative is appreciably GREATER appropriately compared to net of moist convection bidirectional which is 0 W/m^2 (80 up evapo-transp. – 80 down rain) in the famous cartoon. The 80 down is a component of the 333 shown.
It’s a matter of understanding proper scientific usage. Radiative emissions
from any parcel of matter above 0K are indeed omnidirectional. But the heat
transfer–the NET vector of energy fluxes between juxtaposed parcels–is
always unidirectional, from warmer to colder. It is to the latter, not to
directional radiative intensities per se, that conservation laws apply.
Thus in K&T’s cartoon, the insolation of 161W/m^2 absorbed by the surface is
closely balanced by the sum of moist convection (97W/m^2) and an outgoing
radiative transfer of 63W/m^2. Clearly, much greater radiative transfer
could not be sustained by available insolation, which is the sole source of
energy considered here. Conversely, any oppositely directed radiative fluxes
yielding an outgoing NET of 64W/m^2 from the surface would algebraically
balance the insolation.
Not even K&T, however, indulge in the fanciful notion that moist convection
is is somehow balanced thermally by falling rain. It’s only the masses of
evaporation and precipitation–not their thermal energy content–that balance on
climatic time-scales. There is no such component in their backradiation figure.
1sky1 3:59pm: Ok omnidirectional if you will. In a hemisphere of directions away from a positive radii surface. 1st law applies to the omnidirections in accounting energy transfers to/from an object, the net being the end result producing a stable T in that object or changing T if unbalanced energy transfer, not stable.
In the cartoon global moist convection including thermals is balanced 97 up (LH energy transfer up at expense of L&O surface energy) and 97 down (release of LH & downdrafts at expense of atm. energy in 333) balanced over the approx. 4 years observed, no net change in 1st law energy transfer accounting to the reasonable accuracy available from study of these global processes.
The surface insolation 161 is roughly in balance omnidirectional over the 4years with 160 net outgoing omnidirectional (your net 63+97=160) with ~1 net absorbed (after round off) for politics. And lengthy blog discussions.
There’s still much confusion evident in your claim that a 97W/m^2 downward transfer occurs due to “release of LH and downdrafts.” This is simply algebraic conjecture without any basis in physics. And it’s senseless to speak of “omnidirectional balance” with insolation when the actual heat transfer is either zero or has a distinct direction, which in the case of climate is from from thermalized surface through the atmosphere to space.
1sky1 4:17pm – Don’t understand what you mean by “omnidirectional balance” as I didn’t write that and omnidirectional is your word. The radiation leaves the surface in a hemisphere of directions. The science is well founded by tens of different authors. Many different earth energy budget papers. The 333 all-sky emission to surface bath has 4 components, reasonably explained in the papers.
I wrote of omnidirectional emissions from an arbitrary parcel of matter. You wrote: “The surface insolation 161 is roughly in balance omnidirectional…” Can’t make any sense of that. Nor does the assertion that “The science is well founded…” make any sense in relation to a supposed downward component of heat transfer that ostensibly cancels the transfer via moist convection. I fear your confusing mass transfer with heat transfer and kinetic energy with potential. In any event, the 333W/m^2 backradiation in the cartoon is a highly tenuous, model-based figure, which varies widely from author to author.
How does the IPCC TSI annual change of 22% correspond to the annual variation of the so called solar constant between 1414 and 1323 perihelion to aphelion? That is a swing of about 90 W/m2.
I also want to echo several of the comments that I suspect the variation of the spectral composition may need to be taken into greater account. I think this could be summarized by pointing out that
Not all Watts are equal. (apologies to the site owner)
Indeed, not all watts are equal due to energy residence time. See my post up-thread here for more detail if interested. http://wattsupwiththat.com/2014/10/25/changes-in-total-solar-irradiance/#comment-1771661
The 22 W/m2 is your ~90 W/m2 divided by four to give us a global 24/7 average. Your number is correct, but it’s for the instantaneous TSI, and in general forcings are calculated on a global 24/7 average basis..
So, if I read this right, your point is that the earths orbit creates a 22W/M-squared change based on our distance from the sun. Which is vastly greater than the variation of TSI or any component of it. If this is true then your cloud based negative feedback system is most likely correct, or we would have frozen or fried a long time ago.
Would you suppose that the issue then is not too much energy (earth seems to handle that fine) but what about if the incoming energy is insufficient to maintain current temps, could that be a driver to the occasional abrupt cold shift. Since I am reasonably sure that no one disregards the Ice Ages.
Anyhow, I have to agree Willis, you continue to make a sound argument.
To me that is the simplest and most likely explanation. I believe the ITCZ reacts quickly to changes in TSI while everything else is lagging.
Willis, is there also a breakdown of monthly variation in spectrum? As Milodon noted above, the uv spectrum is much more energetic. Perhaps an increase in UV proportion compensates for lowered TSI.
Yes there are monthly data, but SORCE & SUSIM show some differences:
http://link.springer.com/article/10.1007%2Fs11207-014-0535-5
Here’s the big picture:
http://wattsupwiththat.com/2010/12/22/sorces-solar-spectral-surprise-uv-declined-tsi-constant/
With good commentary by Leif, aka Dr. Svalgaard, the Sun King.
“where is the effect of the ~ 22 W/m2 annual variation..”
I agree that the climate system is somewhat buffered from external forcings …”the system reacts to maintain the same temperature despite the changes in forcing.”
I would add that the thermal lag of the climate system is VERY significant, here is one example, maximum ice extent in some Greenland areas occurs around March 22, a full 3 months after the summer solstice, and well after the surrounding air temperature has reached maximum. Who knows what deep ocean currents do to incoming heat.
I’ve heard that the deep ocean hides incoming heat.
“maximum ice extent in some Greenland areas occurs around March 22, a full 3 months after the summer solstice, and well after the surrounding air temperature has reached maximum”
I don’t think that makes any sense. You must mean Antarctica not Greenland.
[Maximum solar radiation is the first week in January at 1410 watts/m^2.
Minimum southern ice extents varies a bit, about Feb 22 on average, as you noted.
Maximum northern (Arctic) ice extents occurs a bit later, about March 22 – April 5.
equal solar exposure occurs on the equinox at ar 22 each year., regardless of solar insolation.
Maximum Arctic solar exposure (not solar insolation!) occurs on June 22.)
Minimum solar radiation is much later at July 15 – 20 at about 1320 watts/m^2)
Equal solar exposure occurs again on September 22.
Minimum Arctic extents happems about the same time (Sept 15 – 26) each year.
maximum Antarctic sea ice extents occurs shortly thereafter between Sept 22 and Oct 6 each year. .mod]
Mod, thank you.
It may be a good topic for a lead post to cover your insertion above. It was not really clear to me prior to your addition and may help put into perspective (at least for any new to the discussion of climate) the magnitude of any difference in TSI.
Systems that are stable (and our climate has been stable for millions of years) contain negative feedback. How else could they remain stable. Is it credible that we could have lasted this long without a mechanism (like clouds reflecting light) providing negative feeddack? If a “tipping point” existed, wouldn’t something have pushed us past it already?
I agree that negative feedbacks must dominate in a homeostatic system such as the earth’s climate. However for 2.6 million years its climate has fluctuated within a broad range around ten degrees C or more from glacial to interglacial phases. That’s stable, but with wide swings on the order of tens to hundreds of thousands of years. Before that, there have been even wider swings between Ice House (as now) & Hot House conditions.
http://news.discovery.com/earth/earth-atmosphere-shrinking.htm CO2 is blamed for everything. Hot cold….doesn’t matter. Don’t you forget it. Truth is…. Your TSI is missing CME.
Someone please tell me why the dst index can no longer crack -150
“Rapid solar irradiance variations with larger amplitude are superimposed on the 11‐year cycles; decreases on time scales of days to weeks can be as large as 4.6 W m−2.”
Greg Kopp and Judith L. Lean, A new, lower value of total solar irradiance: Evidence and climate significance, 2011
URL:
http://chicagowilderness.org/members/downloads/Strategic/February%2011_CCTF_solar_irradiance.pdf
My comment on Kopp & Lean:
To put this in context, Loeb et al.(2012) cite 0.5 Wm-2 as the radiative imbalance stored in the world ocean.
Norman G. Loeb, John M. Lyman, Gregory C. Johnson, Richard Takmeng Wong, Brian J. Soden and Graeme L. Stephens, Observed changes in top-of-the- radiation and upper-ocean heating within uncertainty Nature Geoscience, 2012 .
http://www.met.reading.ac.uk/~sgs02rpa/PAPERS/Loeb12NG.pdf
Variations in solar irradiance were reported in greater detail in 2010 with suggestive indications of regional differences in downward and upward radiative flux.
Pamela E. Mlynczak, G. L. Smith and P. W. Stackhouse Jr. Interannual variations of surface radiation budget, 22nd Conference on Climate Variability and Change, 2010.
https://ams.confex.com/ams/pdfpapers/163815.pdf
Reliance on TSI alone in the GCMs is, sad to say, not even the worst assumption behind the GIGO models which the CACA Team imagine to be good enough for policy makers to dismantle civilization.
It is interesting that some scientist insist they are measuring all outgoing radiation, even though there are two giant holes where the satellites can not measure, namely the poles. If basic ocean atmospheric theory is right, then heat gets transported to the poles in vast amounts to be radiated into space. In many ways ocean science is only possible to understand because we assume that the ocean has been around long enough to achieve equilibrium. So energy in by definition has to equal energy out for the total system. Trying to measure most of the earth and all the incoming energy, by definition is not going to be equal. I would say we should do a better job of measuring but in reality, there are many more important things to spend money on!
“”””……Figure 1. Variations in TSI. The upper panel (red) shows the actual measured TSI. …..”
I think that I read here that this is variations in TSI , and I believe you stated that means Total Solar Irradiance, and I also read the above excerpted annotation, that the red shows the actual measured TSI, which I take to mean that these numbers are taken from an actual radiometer instrument, rather than derived from some model formula.
Now I actually have such a radiometer of sorts; not as sophisticated, as NASA satellite borne instruments, and calibrated to read in a different set of units, so I have to apply a conversion factor, to get W/m^2.
Also, I have to measure at sea level, so I lose in the atmosphere transmission.
And never ever have I got a reading as low as 330 to 350 W/m^2.
So I would really like to see an actual photograph of an actual radiometer instrument readout that reads numbers like those red ones.
Numbers derived from a climate model, are NOT “actual measured numbers”.
Your post brings up the other problem, the TSI being discussed is the average for the earth. The spot directly in line with the sun is about 1360. Half the earth is at 0. The side facing the sun goes from very small to a maximum of 1360 or so. Averages, means etc are useless for models because they create strange behavior in the model. To be accurate the model has to actually get relatively accurate numbers. I can’t imagine that any good modeler would actually use an average like that. So mostly the idea of an Average TSI is not a very good way to talk about TSI related to Climate. Particularly if Willis’s Hypothesis is true. What makes his Hypothesis so powerful is that the clouds would be moderating a 1360 W/MSquared signal. So small variations in cloud cover would have a huge change in energy into the system. In practice this is demonstrated by the strange cap to surface ocean temperatures in the tropics. So your correct, it is highly unlikely that you would ever get a reading as low as 330-350 in the middle of the day.
a^4+b^4 doesn’t equal (a+b)^4
Being a bit more serious – could it be that the difference in albedo during the summer months at the poles is enough to negate the difference (as well as a little lag in response)?
George, as David said, the 340 W/m2 are a global 24/7 average. If you only take measurements during the day you will assuredly get higher numbers most of the time.
Your assumption that this means that the scientists are using models, or that they are not using instruments to do the measurements, is simply wrong.
Regards,
w.
For a^4+b^4 = (a+b)^4, there are uncountably infinite number of solutions for a when b is 0, and vice versa!
Well Willis, I don’t believe I’m wrong at all.
“”””…Total solar irradiance, also called “TSI”, is the total amount of energy coming from the sun at all frequencies. It is measured in watts per square metre (W/m2). …”””
See it says TSI is the “total” amount of energy coming from the sun at all frequencies. It doesn’t say it is the “average” value over the earth.
And let’s all just ignore, like good scientists, that it is not energy at all, but the instantaneous areal density of POWER; the instantaneous rate at which solar energy arrives at earth orbit. Power is not an average of anything, it is a differential instantaneous quantity. The “average” power delivered by the atomic bomb dropped on Hiroshima, is almost unmeasurable. But that city did not respond to that average power, it reacted to the instantaneous power in real time, and was completely destroyed.
The earth also responds to the instantaneous power from the sun in real time, and it has a value of about 1362 +/- 45 W/m^2 over the course of a yearly orbit of the sun. And those are the numbers that are reported from the several satellites that continuously measure it.
You don’t have to explain to me about dividing by four. That is a necessary fiction of a model, that thinks the earth responds to averages. And nobody ever measured an average; it is a computed number from a model.
No matter how long you wait, you can never boil an egg on a sidewalk that receives a continuous “tsi” input of 340 W/m^2.
george e. smith October 26, 2014 at 11:01 pm
george, please re-read what I said. I said:
Note what I said was wrong.
As to whether we should use averages or not, averages are used all the time in science. Despite that, you say:
“Necessary fiction of a model”? george, averages and other calculated quantities are used in nearly every walk of life, and for a good reason—they increase our knowledge about what’s going on. Knowing whether the median family income is going up or going down is an important piece of information, despite the fact that nobody ever measured a median.
In particular, in climate science we have both intermittent downwelling radiation from the sun, and continuous downwelling radiation from the GHGs in the atmosphere … how do you propose to compare their global effects, or prepare a global energy budget, without using averages?
Yes, you are correct that “nobody ever measured an average” … but so what? The fact that averages are calculated from measurements doesn’t make them useless, we use them daily in all kinds of real-world situations, along with a host of other calculated quantities (e.g. standard deviations, medians, ranges) that are also calculated from measurements. If you say that the temperature measured in a certain spot varied by 13.6° over a given time period, that’s not measured either, it’s calculated just like averages and standard deviations … again, so what? It still tells us something we didn’t know about the physical situation.
Finally, are there times when an average can mislead us? Most certainly, particularly averages of intensive quantities. Don’t get me wrong, I’m not fond of averages. I use them with caution.
But TSI is an extensive quantity, so perhaps you could give us a real-world example of where using a global 24/7 TSI average, when discussing the global situation, has actually led us to a false conclusion that would have been avoided using the observational data.
w.
PS—You say:
True, and I understand the issue you are raising … but that’s a horrible example. You can never boil an egg on a sidewalk, period. Go try it sometimes, set a pot of water out on a sidewalk and report back to us on how long it takes to boil.
I’ll give you a quick one: The so-called Arctic death spiral falls on its face if you don’t use “global averages and average albedos and average solar exposure times over average months.”
Analyze the solar radiation absorbed and reflected from Arctic sea ice and from open ocean water through a clear atmosphere at the latitude of the edge of the measured sea ice in the Arctic and Antarctic for every day of the year and for every hour of every day. For seven month’s of the year, more heat energy is lost from the open Arctic ocean compared to an ice-covered Arctic than is gained by the “darker albedo” of the open Arctic Ocean. Less Arctic sea ice, more energy losses seven months of the year.
But, every month of the year, more energy is reflected from the ever-expanding Antarctic sea ice than was absorbed by its formerly open surface. The difference becomes particularly striking when you realize that the lowest measured albedo of Arctic sea ice occurs at the same time of the year as the lowest TOA radiation values. But when Antarctic sea ice is exposed to continuous sunlight – while it is NOT at its minimum extents yet! – it is receiving 92 watts/sec MORE solar radiation than the Arctic sea ice was up north under its partial sunlight. Look at both at March 22: Exactly equal sunlight hours, but the Arctic sea ice edge is at its maximum extents at latitude 70 – 71 north. The Antarctic sea ice is expanding from its minimum, but is also at latitude 67.5 south. Both receive about the same energy, right?
Now look at the other equinox: The Antarctic sea ice is near maximum at latitude 58-59 south, but the Arctic sea cie is at its yearly minimum of 3 – 4 Mkm^2 at latitude 78 – 79 – 80 north. Sure, the two areas receive the same hours of sunlight. But each square meter of Antarctic sea ice receives five times the solar energy the Arctic sea ice receives!
All frequencies? How did they measure the microwave energy? And at the other end ultra high UV and x rays? Or did they measure it at all? No where is the energy flux explained or the spectrum isolated. You do know why c4 plants start to change when the earth shifts in the fall. I know .. the atmosphere filters out a certain frequency 770 nanometers. Wait is that infrared?? Did they actually measure the frequency of microwave radiation that water responds to? WHOA call the CAGW people co2 is going to cause plants to stop blooming in the spring. So many averages!!! The IPCC averaged the spectrum response, (if they did that) then they averaged the totals… and then averaged the averages… I don’t think they did much science, I think they are guessing to prove a point.
rishrac October 27, 2014 at 11:48 pm
All frequencies? … Or did they measure it at all?
This is one the most persistent misconceptions on this topic. YES we measure ALL frequencies by the simplest of methods: letting raw sunlight fall into the sensor and measuring how much the sensor heats up [actually the sensor is kept at a constant temperature and the electric current needed to heat the sensor to keep it at a constant temperature is a measure of the energy received by the sensor – but this is a detail]
Most amplifiers I would consider useful have an input, an output, and some kind power requirement. Just where would this TSI amplifier get its power from ?
From the sun, ie solar irradiance.
http://wattsupwiththat.com/2013/04/17/another-solar-to-climate-amplification-mechanism-found/
The TSI both the input and the power supply ?
BS, someone has concocted a clever sounding phrase and built a fable around it
W-
If you XY plotted your 3rd (difference) graph’s data vs. the SSN record since 2000, then you’d probably have an R^2 of about 0.9. That graph is just another proxy for the 11 year solar (last half of 23, first half of 24) cycle. And we’ve gone over that many times here at WUWT, ad nauseum, on the full historical SSN vs temp anomalies, etc.
Meanwhile KC is getting spanked by SF, dangit!!!
Cheers,
Joel
…Lots of folks claim that the small ~ 11-year variations in TSI are amplified by some unspecified mechanism, and thus these small changes in TSI make an observable difference in some aspect of the temperature….
Actually…
…Lots of folks claim that the small ~ 11-year variations in TSI [influence] some [unknown] mechanism, and these small changes in TSI [contribute] to an observable difference in temperature….
I just did a quick run through the thermal lag effects to be expected due to the oceans. All else being equal, about 160/240 of that 11 w/m^2 oscillation amplitude ought to be absorbed by the oceans. Earthly surface temperatures aren’t going anywhere without the ocean surfaces going along. The result of the calculation is about a 0.2 C temperature oscillation amplitude repeating yearly with a normal seaonal lag. My guess is that cloud and wind pattern variations would smear that out into something much smaller yet.
Willis, Thanks for asking a very pertinent question. Very astute! Clearly there must be a very strong negative feedback somewhere or those ocean temperature variations would stick out like a sore thumb.
There is this interesting plot http://stevengoddard.wordpress.com/2014/10/25/relationship-of-sea-level-and-lower-troposphere-temperature-along-the-equator/ (that for me makes the satellite data look suspicious) that shows there is a large effect of changing ocean currents on global temperature and everything else is insignificant.
At the risk of stating the obvious and of asking a really silly question, why are there two peaks and one trough every 12 months in the seasonal component of TSI shown in fig1? If it is a “global 24/7 average” with global being the operative word, shouldn’t there be two peaks and two troughs in 12 months?
If the answer is yes, then the hemispherical changes would cancel each other.
If there is a “real” global annual change in TSI it should be occurring every three months (Equinox, solstice, equinox, solstice).
My apologise Willis, if I’ve been impertinent.
I did struggle to understand what you meant.
cheers,
Scott
There is one peak [on Jan. 4th] and one trough [on June 4th] each year as is clear from Willis’s graph.
So Svalgaard, the peak in Willis’s graph coinciding closely with NH winter, which also coincides closely with perihelion, means that NH winters are both shorter and receive more insolation than SH winters. Does this not mean that the solar variation portion of global warming would necessarily be more pronounced in the NH?
Thank you for entertaining a fool! I was mixing up the word seasonal and thinking of axis tilt and not perihelion and aphelion!
cheers,
Scott
Only even year dates are given, the odd year dates are omitted. There is only one peak and one trough every 12 months – as is should be.
TSI reconstructions completed by solar scientists show between 1.5 W/m2 and 2 W/m2 and 3.5 W/m2 of TSI increases just between 1900 and 1950, and between 2.5 W/m2 and 3 W/m2 and 4.5 W/m2 of TSI increases since the 1600s/1700s:
———————————————-
http://lasp.colorado.edu/images/science/solar_infl/Surface-Temp-w-paleo.jpg
http://www.biocab.org/Solar_Irradiance_English.jpg
http://www.climatedialogue.org/wp-content/uploads/2014/10/Scafetta-fig-1.png
———————————————
But the real solar forcing comes in shortwave, especially from variations in clouds and aerosol depth that allow more or less solar radiation to penetrate the Earth’s oceans. These changes in albedo dwarf the radiative forcing power of CO2.
Here’s what the IPCC says about the total amount of radiative forcing in W/m2 contributed by human activity (mostly burning fossil fuels) from the years 1750-2005:
————————————————-
“The understanding of anthropogenic warming and cooling influences on climate has improved since the TAR, leading to very high confidence that the effect of human activities since 1750 has been a net positive forcing of +1.6 [+0.6 to +2.4] W m–2.”
————————————————-
So, according to the IPCC, the total amount of radiative forcing contributed by humans to the energy flux balance has been just 1.6 W/m2 during the 256 years between 1750 and 2005. The IPCC authors also wrote this about how climate change occurs:
————————————————
“Global climate is determined by the radiation balance of the planet (see FAQ 1.1). There are three fundamental ways the Earth’s radiation balance can change, thereby causing a climate change: (1) changing the incoming solar radiation (e.g., by changes in the Earth’s orbit or in the Sun itself), (2) changing the fraction of solar radiation that is reflected (this fraction is called the albedo – it can be changed, for example, by changes in cloud cover, small particles called aerosols or land cover), and (3) altering the longwave energy radiated back to space (e.g., by changes in greenhouse gas concentrations). In addition, local climate also depends on how heat is distributed by winds and ocean currents. All of these factors have played a role in past climate changes.” —IPCC AR4
————————————————
Of course, (3) is where the 1.6 W/m2 of anthropogenic RF comes into play. The changes in surface incident solar radiation (2) are elicited primarily by changes in clouds and aerosols (albedo). Simply put, more cloudiness and aerosol depth means less sunlight penetrates to the Earth’s surface, or dimming. Less cloudiness and aerosol depth means more sunlight reaches the Earth’s surface, called brightening.
There is a well documented record of global brightening and global dimming trends during the 20th century. And this record clearly shows a correlation with temperature, and a much, much stronger radiative forcing (W/m2) influence relative to the anthropogenic influence. During the 1980s to 2000s alone, albedo changes (brightening) contributed between 2.5 and 10 W/m2 of radiative forcing, which directly corresponds to the warming that took place during this period. This easily dwarfs the radiative forcing strength of the anthropogenic influence alleged by the IPCC (0.3 W/m2 per decade between 1951 and 2011).
——————————
Below are just some of the many papers that document the global brightening and dimming trends of the 20th century, including the dimming that led to flat to cooler temperatures during the 1950s-1980s, and the brightening that led to the warmer temperatures in the 1980s, 1990s, and 2000s.
—————————————
ftp://bbso.njit.edu/pub/staff/pgoode/website/publications/Palle_etal_2005a_GRL.pdf
Traditionally the Earth’s reflectance has been assumed to be roughly constant, but large decadal variability, not reproduced by current climate models, has been reported lately from a variety of sources. There is a consistent picture among all data sets by which the Earth’s albedo has decreased over the 1985-2000 interval. The amplitude of this decrease ranges from 2-3 W/m2 to 6-7 W/m2 but any value inside these ranges is highly climatologically significant and implies major changes in the Earth’s radiation budget.
—————-
http://onlinelibrary.wiley.com/doi/10.1002/2014JD021877/abstract
Radiative forcing in both the short and long-wave lengths reaching the Earth’s surface accounted for more than 80% of the inter-annual variations in the mean yearly temperatures measured at Potsdam, Germany during the last 120 years [1893-2012]. Three-quarters of the increase in the long-wave flux was due to changes in the water content of the lower atmosphere; the remainder [25%] was attributed to increases in CO2 and other anthropogenic, radiatively active gases. Over the period radiative forcing in the short-wave flux [solar forcing] slightly exceeded [0.76 W/m2 per decade] that in the long wave [0.64 W/m2 per decade].
[The total long term radiative forcing for the Sun was 9.12 W/m2 for the 120-year period. The total long term radiative forcing from CO2 was 1.92 W/m2 for the 120-year period.]
—————-
http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-12-00482.1?journalCode=clim
Surface incident solar radiation G determines our climate and environment, and has been widely observed with a single pyranometer since the late 1950s. Such observations have suggested a widespread decrease between the 1950s and 1980s (global dimming), that is, at a rate of −3.5 W m−2 decade−1 (or −2% decade−1) from 1960 to 1990. Since the early 1990s, the diffuse and direct components of G have been measured independently, and a more accurate G has been calculated by summing these two measurements. Data from this summation method suggest that surface incident solar radition increased at a rate of 6.6 W m−2decade−1 (3.6% decade−1) from 1992 to 2002 (brightening) at selected sites.
—————-
http://www.sciencedirect.com/science/article/pii/S1352231014007456
Total global solar shortwave (G) irradiation and sunshine duration were recorded at nine Spanish stations located in the Iberian Peninsula. Averaged series (using the nine locations) showed a statistically significant decrease in annual G [global dimming] from 1950 to the mid 1980s (−1.7%dc−1) [-8.5 W/m2] together with a significant increase [global brightening] from the mid 1980s to 2011 (1.6%dc−1) [+8 W/m2].
—————–
http://onlinelibrary.wiley.com/doi/10.1029/2008JD011290/abstract
The decadal trend shown in the 5-year running mean indicates a period of rapid increase [solar radiation reaching the surface/brightening] starting in late 1930s and continuing to early 1950s with a change of 10 W m2. The dimming trend from the early 1950s to the late 1980s shows a decrease of 13 W m2. The subsequent increase starting in late 1980s is about 10 W m 2 by 2005. These changes are not confined to a small number of stations in western Europe, but shared by more than 400 other sites where global irradiance has been continuously observed for more than 40 years.
—————
http://onlinelibrary.wiley.com/doi/10.1029/2010JD015396/abstract
We find distinct patterns of dimming and brightening in the aerosol optical depth and thus clear-sky downward surface shortwave radiation (SSR) in all analyzed subregions. The strongest brightening between 1973 and 1998 under clear-sky conditions is found in mid-Europe (+3.4 W m−2 per decade [8.5 W m−2 total], in line with observations).
——————
http://www.sciencemag.org/content/308/5723/850.abstract
Long-term variations in solar radiation at Earth’s surface (S) can affect our climate, the hydrological cycle, plant photosynthesis, and solar power. We observed an overall increase in S [solar radiation] from 1983 to 2001 at a rate of 0.16 watts per square meter (0.10%) per year [3.04 W/m-2 total].
——————
http://www.atmos-chem-phys.net/13/8505/2013/acp-13-8505-2013.html
[T]here has been a global net decrease [of 3.6%] in 340 nm cloud plus aerosol reflectivity [which has led to] an increase of 2.7 W m−2 of solar energy reaching the Earth’s surface and an increase of 1.4% or 2.3 W m−2 absorbed by the surface [between 1979 and 2011].
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http://journals.ametsoc.org/doi/pdf/10.1175/BAMS-D-11-00074.1
Literature estimates for the overall SSR decline during dimming (1950s to 1980] range from 3 to 9 W m−2, and from 1 to 4 W m−2 for the partial recovery during subsequent brightening [1980s to 2000] (Stanhill and Moreshet 1992; Liepert et al. 1994; Abakumova et al. 1996; Gilgen et al. 1998; Stanhill and Cohen 2001; Alpert et al. 2005; Kvalevag and Myhre 2007; Kim and Ramanathan 2008; Wild 2009).
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http://onlinelibrary.wiley.com/doi/10.1002/joc.4107/abstract
The annual sunshine duration mean time series shows a decrease from the early 1960s to the late 1970s [in Iran], in line with the widespread dimming of surface solar radiation observed during this period. By the early 1980s, there is an increase in sunshine through the end of the 20th century, aligning with a well-known and well-documented brightening period.