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Climate Hustle

Sun & climate: moving in opposite directions

What the science says...

Select a level... Basic Intermediate Advanced

The sun's energy has decreased since the 1980s but the Earth keeps warming faster than before.

Climate Myth...

It's the sun
"Over the past few hundred years, there has been a steady increase in the numbers of sunspots, at the time when the Earth has been getting warmer. The data suggests solar activity is influencing the global climate causing the world to get warmer." (BBC)

Over the last 35 years the sun has shown a cooling trend. However global temperatures continue to increase. If the sun's energy is decreasing while the Earth is warming, then the sun can't be the main control of the temperature.

Figure 1 shows the trend in global temperature compared to changes in the amount of solar energy that hits the Earth. The sun's energy fluctuates on a cycle that's about 11 years long. The energy changes by about 0.1% on each cycle. If the Earth's temperature was controlled mainly by the sun, then it should have cooled between 2000 and 2008. 

TSI vs. T
Figure 1: Annual global temperature change (thin light red) with 11 year moving average of temperature (thick dark red). Temperature from NASA GISS. Annual Total Solar Irradiance (thin light blue) with 11 year moving average of TSI (thick dark blue). TSI from 1880 to 1978 from Krivova et al 2007 (data). TSI from 1979 to 2015 from PMOD (see the PMOD index page for data updates).


The solar fluctuations since 1870 have contributed a maximum of 0.1 °C to temperature changes. In recent times the biggest solar fluctuation happened around 1960. But the fastest global warming started in 1980.

Figure 2 shows how much different factors have contributed the warming. It compares the contributions from the sun, volcanoes, El Niño and greenhouse gases. The sun adds 0.02 to 0.1 °C; volcanoes cool the Earth by 0.1-0.2 °C; natural variability (like El Niño) heats or cools by about 0.1-0.2 °C; and greenhouse gases have heated the climate by about 0.8 °C.

Contribution to T, AR5 FigFAQ5.1

Figure 2 Global surface temperature anomalies from 1870 to 2010, and the natural (solar, volcanic, and internal) and anthropogenic factors that influence them. (a) Global surface temperature record (1870–2010) relative to the average global surface temperature for 1961–1990 (black line). A model of global surface temperature change (a: red line) produced using the sum of the impacts on temperature of natural (b, c, d) and anthropogenic factors (e). (b) Estimated temperature response to solar forcing. (c) Estimated temperature response to volcanic eruptions. (d) Estimated temperature variability due to internal variability, here related to the El Niño-Southern Oscillation. (e) Estimated temperature response to anthropogenic forcing, consisting of a warming component from greenhouse gases, and a cooling component from most aerosols. (IPCC, AR5, Chap 5)

Some people try to blame the sun for the current rise in temperatures by cherry picking the data. They only show data from periods when sun and climate data track together. They draw a false conclusion by ignoring the last few decades when the data shows the opposite result.


Basic rebuttal written by Larry M, updated by Sarah

Update July 2015:

Here is a related lecture-video from Denial101x - Making Sense of Climate Science Denial


Last updated on 28 November 2016 by Sarah. View Archives

Printable Version  |  Offline PDF Version  |  Link to this page

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Comments 801 to 850 out of 960:

  1. Ok, I am caught up with the discussion. I disagree that this is a sun discussion because my point is the temperature of the Earth changes separate from the energy from the sun for the exact reasons that Tom states in #798.

    The SH varies less because there is more ocean and less land. The NH drives the global temperature because it has more land. As he also pointed out it is simply inaccurate to apply the insolation of London as a global change in energy.

    Rob and Muon continue to miss my point (but deride me anyway). My point is that the Earth's geography plays a very important factor in the Earth's temperature.

    If the Earth's orbit was a perfect circle, but with the same tilt. The Earth as a whole would receive the exact same energy every day of the year. The temperature would vary based on the geography of the land that was receiving the direct and indirect energy. Winters would be colder than they are now and summers would be hotter than they are now.

    I am baffled at the deriding discussion between Rob and Muon when they are ignoring the point of discussion.
  2. John (TIS) @ 801... The problem with your analysis here is that what you're saying doesn't allow a mechanism for current warming. Look at the overall temperature trend of the Holocene (even per your Penny ice cap chart). Compare it with the Holocene shown in the Vostok record and the Byrd ice core. All these put together you can see that over the Holocene we are in a slow cooling trend that is orbitally forced (Miller 2010).

    But we are now seeing nearly all indicators of temperature pointing one direction. Up. The planet is warming. The entire planet. That is clearly not being cause by the difference in land mass between NH and SH.

    John, the whole reason all the temperature data sets use an anomaly is because you have to look at the overall trend, not the annual signal. The annual signal tells you very little, if anything, about any kind of forcing.
    Response: [DB] Fixed date. Rob, we've been hearing a lot of conflation by commenters between temperatures and anomalies lately. It's probably time to put together a post on the subject. I can do one later this week unless someone has more time before then.
  3. TIS: "I am baffled ..."

    I'm baffled at this whole question. To that extent, I guess I am missing your point.

    You stated "In January the Earth gets ~7% more energy than it does in July, but July is also ~4C warmer. Explain the warmer July to me without using geography."

    If I am not mistaken, the 7% in question is the % difference between the Jan and July average solar radiation at TOA, as described in my comment and in this graphic. I checked the values, averaging all latitudes over each day; it is indeed 7% more in January and I agreed with that.

    Forgive the ghastly colors, it was the first one I found.

    By your 'July is 4C warmer,' I naturally took that to be in reference to the NH. The graph for London bears out the point that temperature follows net radiation.

    I'm baffled at how you missed that I mentioned the cited source had several other examples. Here's one from the SH, specifically Bulawayo, Zimbabwe, 20S 29E:


    Once again, temperature follows net radiation, even in the SH. I don't deny that geography has a moderating influence, but it is certainly not a driving factor. Differential heating of land vs. ocean is in response to solar input, is it not?

    But your original question said 'explain the warmer July without geography'. Your question made no mention of the difference between incoming and net radiation and that was the focal point of my response.
  4. Rob (802),
    I understand the reason why anomaly is used. Ignoring the actual temperature is not useful though.

    For instance. During the NH summer the Earth radiates away more energy than it does during the NH winter. That is because RHT is dependent on actual temperature. Snow, ice, humidity are all determined by the actual temperature.

    During the NH summer the average temperature of the Earth is at it's warmest. Enormous amounts of energy go into increasing the total water vapor in the atmosphere. Latent energy transfers to the atmosphere increase as does RHT and convective heat transfer.

    The behavior of the Earth is different at the two ends of the temperature extremes. Geography is the reason why those differences are real.

    These annual cycles are likely drivers of events like the ENSO that does show up in the anomaly charts that you are so concerned about. I pay attention to the trend in the anomaly, but I don't give it the overwhelming weighted importance that you do.

    The global anomaly for February is basically zero for both the UAH and RSS sets, but I don't think that is very important. That temperature of the Earth for February was right at 12.1 °C tell more about how the Earth is behaving than saying the anomaly is zero.

    I do think it is worth considering that over the next three months that will increase to ~16°C while the energy the Earth gets from the sun will decrease by several percent. Saying that this effect is not important is... rather incoherent.
  5. Muon (803),

    If the two hemisphere's had equal geography then January would be warmer than July with the current orbital parameters. The NET energy you refer to is local.

    Picking London explains why that location is cooler in winter, but does nothing for why the entire hemisphere reacts more strongly than the SH. That is where geography enters into the equation.

    Please see #802 for why I say the actual temperature matters.

    None of what I am saying actually goes against global warming, but for some reason when I say something people tend to disagree anyway. I of course understand that, but it is nonetheless an interesting effect by my choice of name.
  6. PS... I meant #804. This discussion is kinda long.
  7. John @ 804... It's not incoherent at all! It's expected. It's understood. It has absolutely no net forcing effect over the natural annual cycle. This is just not a mechanism that is driving any warming or cooling trend.

    When you start focusing on the temperature cycle rather than the trend you are completely missing the point of global climate. If you ignore the trend you are just closing your eyes to any potential forcing mechanisms.

    So, that would be my question to you. How would a natural annual cycle drive the trend one way or the other? How would this annual cycle drive ENSO?
  8. TIS @805, people tend to disagree with what you are saying because they try to interpret it as being relevant to the debate. Because it is irrelevant to the debated, they end up misinterpreting you.

    Perhaps you can point out why you think this fact is relevant, bearing in mind that geography has not changed over the last century, but temperatures (and temperature distributions) have.

    For those trying to understand where Inconvenient Sceptic is coming from, this appears to be a lead in to George White's much refuted nonsense.
  9. TIS: "why the entire hemisphere reacts more strongly than the SH."

    This is, of course, an entirely different question, one that leads to Arctic amplification. Yes, the geography of the hemispheres produces different thermal responses. One might suspect that it also has something to do with the fact that there is a very large ice cube down there in the basement.

    I looked again at TOA insolation figures: on an annual basis, the southern hemisphere actually 'receives' ~2% more than the northern. Hardly a significant difference.

    "over the next three months that will increase to ~16°C while the energy the Earth gets from the sun will decrease" Yes, that's been going on for a very long time. To what point?
  10. Rob(807)

    I am not ignoring the trend, I am trying to get to the relevance, but you are still stuck on anomaly.

    It isn't irrelevant and it has nothing to do with that guy who I have not heard of before, but I will take a look since you linked.

    Thank you for discussing. If there was no CO2 in the atmosphere, how would an identical Earth be different without CO2 in the atmosphere (plants breathe O2 so even plant coverage is identical).

    The geography of the Earth would force the same type of temperature cycle that the Earth currently experiences. NH winter would cause the Earth average to be colder and the NH summer would cause it to be warmer.

    The greater effect would be in the winter when there was less water vapor in the atmosphere. So the Earth would be colder by some value.

    The summer would have a lesser effect because there would be more water vapor that would compensate for the lack of CO2.

    The Earth would still not behave like a blackbody (i.e. there would still be a GHE) because there would still be convection and latent heat transfer to the atmosphere that would keep the atmosphere warmer than 254K.

    So the anomaly difference from normal earth would be greater cooling in the winter, but less of a difference in the summers, but still cooler.

    I am sure we won't agree on the magnitude, but even if the winter difference was 5 °C, then the summer difference would be less than 5 °C. If the summers were 2.5 °C cooler, then on average the Earth would be 3.5-4°C cooler than now.

    One helping factor would be a cooler Earth would need less energy because it would radiate away less energy.

    In this case boundaries of response can be established by looked at the seasonal temperature and atmospheric behavior. Would you agree that the summer effect would be lesser than the winter effect?
  11. TIS,

    How is an unchanging cycle relevant to the trend?

    Plants require atmospheric CO2 for production of food, i.e. photosynthesis.
  12. TIS... You are still failing to explain how this could possibly explain the warming trend.

    My next question is, why do you think even Spencer and Christy present their data as anomaly?
  13. TIS... As to me being stuck on the anomaly, well, everyone is stuck on the anomaly because that is how you see the trend. The trend and related mechanisms driving the trend are what it's all about (Alfie).
  14. Going back to the original premisen that because solar radiation has reduced since 1960, the sun has nothing to do with global temperature rise - this agument is flawed. The reason being that according to Wein's Distribution Law for black body radiation, if the sun has cooled such that its total radiation has reduced, then the radiation peak will have also shifted towards the infra red. These means that the Earth is likely to receive more insolation because we know the Earth absorbs radiation in the infra red region than at higher frequencies ( shorter wavelengths )due to the greenhouse ( and other effects ). Hence the rise in global temperatures. Global warming occurs for complex reasons ( and not that well understood by the so-called experts)and attributing it to man made pollution (alone) is nonsense. It has occurred in the past and will occur again in the future. Our contribution to CO2 etc is nothing compared to that produced by vulcanism.


    [DB] Welcome to Skeptical Science!  There is an immense amount of reference material discussed here and it can be a bit difficult at first to find an answer to your questions. 

    That's why we recommend that Newcomers, Start Here and then learn The Big Picture.

    I also recommend watching this video on why CO2 is the biggest climate control knob in Earth's history.

    Further general questions can usually be be answered by first using the Search function in the upper left of every Skeptical Science page to see if there is already a post on it (odds are, there is).  If you still have questions, use the Search function located in the upper left of every page here at Skeptical Science and post your question on the most pertinent thread.

    Remember to frame your questions in compliance with the Comments Policy and lastly, to use the Preview function below the comment box to ensure that any html tags you're using work properly.

    With that out of the way, there is much indeed wrong with your comment, more than can be summed up by just one thread post.  Please break up your many objections into their individual parts and post them on the appropriate thread (that's where the Search function will help you).  Thanks!

  15. John. Nope. Spectral signature in IR range is insignificant. We measure spectra at TOA and earth-bound and what we see is consistent with GHE, not your idea.

    "Our contribution to CO2 etc is nothing compared to that produced by vulcanism."
    This is false. See Volcanoes and global warming

    Global warming occurs for complex reasons ( and not that well understood by the so-called experts)and attributing it to man made pollution (alone) is nonsense.
    Care to support that assertion with some science?

    You might also like to look at Climate has changed before
  16. Whew! I have just finished reading this entire thread. The reason the stratosphere is stratified as opposed to the convective trophosphere below is that the lapse rate is "inverted" and begins warming, forming a stable lid just like the adiabatic inversion that traps smog in the LA basin. The stratospheric inversion is probably not adiabadic, but is thought to result from the absorbtion of UV photons by oxygen, forming ozone. The top of the stratosphere where the oxygen becomes "saturated" with photons approaches the temperature of the earth's surface during solar maxima. Above the top of the stratosphere the lapse rate becomes normal again but there is another or two poorly understood (at least by me) inversions before the TOA.

    Question: what does a satellite measuring the temperature of the earth from space (255K?) really see? Can it distinguish between the spectrum of CO2 absorbtion at the top of the troposphere and the spectrum of ozone absorbtion (approximately half of which should be radiated back to space), or does it see just the triple net of all the refracted, reradiated, conducted, convected energy from the earth atmosphere system?
  17. Hi. First Post, please be nice :)

    Can someone (anyone?) explain why in this graph we are comparing TSI Actuals against Temperature Anomalies? I've done a (very little) bit of stats and one thing I remember is that if you want to compare things you have to get those things onto the same playing field.

    On the whole, SkS does a great job helping me to understand what's going on. Sometimes (like this for example) I'm left wondering why the author didn't do the proper job...

    Response: Using the anomaly instead of the raw temperature merely is a good way of reducing noise. An example of another way of reducing noise is to smooth a curve with a moving average. The anomaly still addresses our question: Does temperature change across time correlate with TSI? Temperature anomaly change mirrors raw temperature change. Think about what the raw temperature curve would look like next to the anomaly curve. A very rough analogy: It doesn't matter whether you plot the temperature in degrees Farenheit or degrees Celsius, if what you are interested in is the shape of the curve across time.
  18. For me, it's just a simple way of showing that TSI and Temp have come completely unhinged in the last 35 years.
  19. Also, what the various temperature system do is determine a global temperature anomaly, (that is, a spatial average of anomalies because these are strongly correlated). It is extremely difficult to determine a global average absolute temperature that has any meaning.
    See Hansen 2008 for detail.

    However TSI is just a number. You can determine an anomaly if you like by subtracting from an arbitary baseline. It cannot change the shape of the curve however.
  20. Thanks, that's helpful. :)

  21. This paper shows the Models underestimate solar forcing by up to six times.

    It makes perfect sense for us to take time to cool the oceans are vast and deep so 30 years of lag time are more than exeptable.
  22. Cole -
    "This paper shows the Models underestimate solar forcing by up to six times."
    It does no such thing. The paper suggests that other TSI reconstructions underestimate the amplitude of TSI changes in the past. It has very little to do with climate models, and in fact specifically notes that their TSI estimates over recent decades, during which we have good measurements, are no different than previous TSI reconstructions.
  23. Cole, Dana's right. I'm not sure you read that paper. In fig 4 there no net change in solar forcing since 1950.

    And why is the 30 year lag relevant? And what justification for 30 year lag other than " the oceans are vast and deep" do you have?
  24. I'll probably do a post on this paper. To be fair, if the reconstruction is correct (which I don't think is plausible), it does suggest a very low climate sensitivity, so you could argue that climate models are wrong in that sense. Sensitivity would have to be in Spencer/Lindzen territory, below 1°C for 2xCO2 if this reconstruction is right. I don't think it's plausible, but should make for an interesting post.
  25. Cole, your linked paper starts :

    The variable Sun is the most likely candidate for natural forcing of past climate change on time scales of 50 to 1000 years.

    And ends :

    We note that our conclusions can not be tested on the basis of the last 30 years of solar observations because, according to the proxy data, the Sun was in a maximum plato state in its longterm evolution. All recently published reconstructions agree well during the satellite observational period and diverge only in the past. This implies that observational data do not allow to select and favor one of the proposed reconstructions. Therefore, until new evidence become available we are in a situation that different approaches and hypothesis yield different solar forcing values. Our result allows the climate community to evaluate the full range of present uncertainty in solar forcing.

    Can you explain in your own words (i.e. not from WUWT) what you get from that paper ?
  26. I read the following from comment #997 in Jeff Master’s blog today. I expect that someone with knowledge will have to pick his writing apart, as an article is making the rounds on the intertubes, apparantly based on Stockwell's writing. What follows is comment #997:

    Another blow to the AGW theory...

    Dr. David Stockwell who has a PhD in Environmental Sciences submitted a recent paper, that shows that solar activity alone, could explain Global Warming. I believe that GCC has more of an impact than the sun, but it's interesting nonetheless.

    Finally, my hibernation of the last 6 months is coming to an end, with the formal submission to a journal yesterday of the fruits of my labor. The main points:
    1. solar forcing is time-integrated and not direct,
    2. accumulation of the 0.1W/m2 increase in solar irradiance in the 20th century explains global warming,
    3. there is a credible explanation for global warming that does not involve increases in human emissions of greenhouse gasses.

    Figure: Cumulative solar irradiance (blue) and volcanic forcing (red) is highly correlated with HadCRU global temperature and explains the trend in temperature since 1950. The direct solar irradiance (orange) is uncorrelated with temperature.
    There are a lot of other points about the model that no doubt I will get into in time. For the moment, here is the Conclusion.
    Contrary to the consensus view, the historic temperature record displays high sensitivity to solar variations when related by slow equilibration dynamics. A range of results suggest that incorrect specification of the relationship between forcings and temperature may be at the heart of previous studies finding low correlations of solar variation to temperature. The accumulation model is a credible alternative mechanism for explaining both paleoclimatic temperature variability and present-day warming without recourse to increases in heat-trapping gases produced by human activities. The grounds on which a solar explanation for late 20th century warming is dismissed should be reconsidered.
  27. I don't know what's going around the intertubes, I couldn't find the paper. Maybe people is talking about nothing. We'll see.

    [DB] Try Stockwell's blog here.

  28. Thanks DB. Actually there's not much there either, only a figure more. Assuming that it can not simply be "solar forcing integration", we need to know more about his model before commenting. And sure I'd not be thrilled by a "mathurbation".
  29. 826, Tor B,

    Until his work is published in its entirety, and available to all, it is only so much blather, and very unlikely to undergo scrutiny, since no one else to date has been able to accomplish what he claims, and quite to the contrary, a number of existing studies demonstrate the opposite. [See the #2 denial argument, It's the Sun.]

    At this point, all you can do is to claim that he claims that he's submitted the masterful diagnosis which overturns all of modern climate science. Forgive me if I don't sit up too straight in my chair.

    At the same time, he will also need to explain other things, like why CO2 is not causing any warming (considering that the mechanism is very well understood, and it would be a huge surprise if that mechanism is totally and completely misunderstood by all atmospheric physicists around the globe).

    Sorry, but your post is only so much "trust me, I know a guy who knows the truth, just wait" hand waving, and as such is a wholly inappropriate claim to make.
  30. Sigh,

    Let Tamino know...probably another crank paper that needs to be refuted.
  31. Stockwell's "work" sounds like the same-old-same-old overfitting of a curve with a whole bunch of parameters.
  32. Tor B @826, Stockwell provides very little information to provide a counter analysis. The majority of the information comes from this diagram:

    As you can see, he plots temperature against the cumulative solar forcing. The only way that can be appropriate is if there has been no increase in Outgoing Longwave Radiation to dissipate the increased incoming solar energy, thus allowing it to accumulate. As a rise in temperature will result in a rise in OLR all else being equal, he leaves entirely unexplained why OLR has not increased over the period, and why it did increase in previous centuries, thus allowing the solar forcing to dissipate and temperatures to not rise as they have in the twentieth century. What Stockwell needs, therefore, is a mechanism that provides a near linear reduction in OLR over time. (Care to guess where this is going?)

    Oddly, and obviously, there is a known mechanism which has been increasingly been reducing the OLR over the course of this century. It is the increase in the Greenhouse Effect due to increased anthropogenic emissions of Greenhouse Gasses. Indeed, the increased forcing (reduction in OLR for a given surface temperature) has risen approximately linearly over the last half of the twentieth century:

    Further, it turns out that using a linear increase in anthropogenic forcings plus solar forcings, plus volcanic forcings plus the MEI (an index of the El Nino Southern Oscillation), an even better correlation with temperatures can be found than that found by Stockwell:

    So it turns out that the evidence Stockwell has uncovered is in fact evidence of an increasing anthropogenic forcing - he is just not good enough an analyst to realise it.
  33. 832, Tom Curtis,

    You win the Comments-Rebuttal-Of-The-Month Award!!!

    [Darn. I wish I'd worked that one through. Very nice job, and a lesson for anyone who has fallen for any such similar denial nonsense. Just playing with numbers is a parlor game, not science. Casual readers should note that the basic problem with Stockwell's analysis was the creation of an arbitrary mathematical mechanism -- the accumulation of solar input -- without any corresponding physical mechanism to justify the assumption. He picked it just because it fit the data, and didn't take the thought process any further. As Tom demonstrated, the missing physical mechanism that justifies the mathematical trick to demonstrate the incline does exist, but sadly, for Stockwell, it's called the Greenhouse Gas Effect.]
  34. Sphaerica (829) appears to miss the intent of my posting "someone with knowledge will have to pick his [Stockwell's] writing apart". Albatross (830) reflects my view: I read a "new" "it's the Sun" and thought folks here could banish it properly. Tom Curtis (832) has done what I am not able to do. Thanks!
  35. 834, Tor B,

    Apologies. Believe it or not, I read your post several times trying to figure out the intent. I even did a google search looking for your past comments, to see what sort of things you've posted previously.

    My bad. I think I've been getting way too feisty lately. Too much nonsense devoid of substance flying around here of late. It's just frustrating.

    Sorry again.

    -- Bob
  36. I find myself skeptical that the current trend of increasing global warming is currently sustainable reasons.

    1) The current increase in global temperatures is a result of burning fossil fuels, releasing energy into the atmosphere. While the global may increase over a period of time, the heat emitted from burning fossil fuels is contained within the bounds of the earth. Eventually (and discounting any changes in solar output), the heat emitted will be reabsorbed back into the surface of the earth, reducing the atmospheric temperature back to near the original temperature of the pre-combusted fuel (the mass of gas surrounding the earth does not hold a candle to the amount of mass contained within the crust).

    2) Fossil fuel supplies are limited, as is the amount of heat we can eject into the atmosphere is finite. At some point we MUST stop putting energy into the atmosphere.

    3) While the heat island effect exists, it is a two way street. Energy is just as easily emitted into space as it is absorbed into the earth. Granted, there will be larger temperature fluctuations within the city than outside of it due to an increased surface area (sq mile to sq mile). The amount of greenhouse gasses in the atmosphere is nowhere near significant enough to significant detract from that.

    4) The amount of greenhouse gasses in the atmosphere, while significant, are unlikely to have anything to do with global warming for the same reason as item 3 above. If it can contain heat well, it rejects it just as well. Energy from the surface of the earth is reflected with the same percentage as energy from the sun. This is not to say it cannot wreck hell on the earth’s ecosystems, just that it a political issue versus an actual energy issue.

    Essentially we are looking at an energy balance problem. All energy enters the earth via solar radiation, all energy leaves the earth via solar radiation. Unless there is a statistically significant solar change, the current temperature fluctuations are due to the energy revolution of the 1900’s. Recent increases in the global temperature can probably (not going do the work) be correlated relatively accurately to the number of cars in use around the earth (or number of people on the earth).

    So from where I stand, blaming temperature increases on CO2 is a fallacious argument, as it is a neutral player.

    [DB] I'm not even sure where to begin...first-off, please read Newcomers, start here.  Then take a gander at The Big Picture.

    1. The current global rise in temperatures is a result of the energy imbalance at the top of the atmosphere, due to rising levels of CO2.  As long as we keep emitting more CO2, the imbalance will continue and so will the rise in temperatures.
    2. The energy being accumulated is not due to energy being released by us, but by the CO2 we release.
    3. UHI is immaterial as scientists measure anomalies, not absolute temperatures.  See also CO2 effect is weak.
    4. How to put this kindly...this makes little sense as written.

    Energy does not leave the system as solar radiation but as thermal emission from the Earth.  CO2 lengthens the exit path by that radiant thermal emission, so the lower levels of the atmosphere heat up due to the increase in back radiation.  See The Greenhouse Effect has been Falsified.

  37. rdmtask... In addition to the moderator's comments you need to be aware that you are coming to a conclusion that is diametrically opposed to the conclusions of the vast majority of the published literature on this topic.

    If you're genuinely interested in learning about the science of climate change you should spend time reading the articles here on SkS. And you don't even need to take the word of the authors of these articles. Almost every one of them fully cite the relevant research. You can follow those links and read the actual research for yourself.
  38. And further note, that we have enough coal to change the CO2 concentration in the atmosphere back to pre-pliocene levels.
  39. As for #4:

    The incoming energy from the sun primarily is shortwave radiation. This is absorbed by the planet and emitted as longwave radiation. The greenhouse gases absorb and reflect this longwave radiation.

    The "greenhouse effect"

    You are arguing against over a century of accumulated scientific knowledge based on your lack of understanding.
  40. The way I read 1 & 2 of rdmtask's comment, is that he/she thinks the heat driving global warming is from the heat given off by burning of fossil fuels, rather than the CO2 given off increasing the Greenhouse Effect.

    This confusion continues here: "All energy enters the earth via solar radiation, all energy leaves the earth via solar radiation" Where he/she appears to claim that the Earth is a star.
  41. Ken Lambert - If you are talking about forcing imbalances, then statements such as "If TSI is above an 'equilibrium' value and stays constant -there is a constant imbalance in forcing which translates to a linearly increasing gain in energy..." are completely unwarranted, as you should well understand. The climate will respond by warming due to increased energy in the system, and reduce the imbalance due to increased TOA radiation.

    The "constant imbalance" phrase is one you have repeated several times in this context - it's been wrong every time before, and it is wrong now, as it implies a constantly increasing TSI - which is not the case.

    "My point is that the TSI contribution is really unknown unless you know the 'equilibrium' TSI which will produce neither warming not cooling in the absence of all the other AG forcings."

    There is no such thing as an "absence of all other AG forcings". The climate is the sum result of all the forcings and feedbacks. Climate change is the result of changes in one or more forcings.

    TSI has changed very little over the past century, where we've seen the most warming, and the 'equilibrium TSI' would have been long since reached at some equilibrium in the absence of other changes. In particular, there has been essentially no change in TSI since 1980. "E pur si muove" - and yet it moves!

    Essentially, you seem to be looking for a unique equilibrium, when any fixed forcing will reach an equilibrium tied to that forcing. Climate changes from that point are due to changes in forcing, and we have an excellent track of what the TSI changes are - negligible.

    The observed climate change is therefore primarily due to the greater than exponential increase in CO2, hence a greater than linear forcing change.
  42. First it is to notice that 'solar activity' means quite more than the single value of TSI. Also of importance, but unfortunately on a low level of scientific understanding according to the IPCC, are things like intensities of mass ejections, number and intensity of flares (2003 showed the most and most intense flares in history - what of course could explain the sharp rise of the OHC in 2003), magnetic fux and the interplay between magnetic fields of both earth and sun (we had a decrease of the earth MF of about 10% in the last 100 years while the solar magnetic flux nearly doubled in the same time).

    Second I wonder why you talk only about the last 35 years. Looking at the graphs in the basic and intermediate sections makes it quite obvious that the former correlation between TSI and temperature was not broken in the 70th but in the mid 40th instead. (Following the correlation would show a temperature level like the current in the mid 60th, but the TSI-level had not reduced significantly, what means that the level was still high until the mid of the last decade. This, of course, depends on the reconstructions that one uses.)
    From my point of view, it suggests itself that the temperature rise of the last 35 years was not caused by the change in the same time, but by the absence of warming in the area of time before.
    So, look at these graphs and tell me why only to speak about the last 35 years when the link was broken 30 years before.
  43. JoeRG - Please see CO2 is not the only driver of climate, and mentally replace "CO2" with "the sun" throughout the article.

    There are a lot of forcings that affect the climate - when looking at climate change we need to look at what the forcing changes are. TSI changes (as with magnetic storms, and ion counts, and galactic cosmic rays) don't correlate with recent warming.
  44. @KR

    Honestly, I know that there is more than one driver of climate and currently no correlation between TSI and temperature.
    The question is here (because of the topic): when did this correlation break? As it is to see in the graphs it was NOT in the 60th or 70th as the basic or intermediate section suggests, it was obviously earlier: in the 40th.

    The TSI rose until the 60th while the temperatures had a kind of timeout. So, and thats is the main part of the question, why we don't speak about the area from the 40th to the 60th - the time when the correlation was broken? To speak only about the last 35 years is a false trail.

    To imagine what I mean you can make a little backyard experiment:
    Take a cattle full of water on an oven, bring a kind of insulation between cattle and heatplate (so that the water temperatur would be constant at higher power) and turn the plate up to a almost constant high level. After a while remove the insulation. What would you expect?
    Would you really mean that the water would stay with the constant temperature? No? So I wonder why the climate science does.
    Of course, we had some kind of climatic insulation in the past: global dimming in general and, according to a recent study, possibly a little impression what a nuclear winter can look like.

    Finally, a possible conclusion is that we had a delayed (but not unexpected) warming that is caused mainly by the sun, resp. by its near constant high level of activity (until the beginning of the last decade). But if you look only at the recent three decades you wouldn't / can't see it (or possibly not want to? - just a general question, not personally).
  45. JoeRG - the "broken correlation" just tells you that some other factor is more important now. The sun is always important. When the real relationship with temperature is:

    Temp = Func(Sun, Albedo, Aerosol,GHG) (which when you right it out properly tells you the temperature on the surface of any rotating planet) then you can hardly make sense of correlation by just looking at
    Temp = Func(Sun)
    Right through 20th century, all the other factors were changing too.

    The problem with delays (ie "recovering" from LIA) is where's the springs in the climate system? Of course there are delays between applying a forcing and getting a response - it takes a long time to heat the ocean - but if you remove the forcing, then by what mechanism can you continue the warming (same applies in reverse too). Even more puzzling, these hidden "springs" must produce an accelerating response after the removal of a forcing. There is no known mechanism for this whereas our ordinary climate understanding explains observations fine.
  46. @scaddenp #845
    The solar forcing remained nearly constant since the 60th and was higher after the break in the 40th. So there was no significant change, even a slight rise. - For the backyard experiment: we had a constant high level of the heatplate.
    The only forcings that were removed partly are the causes of global dimming, but these were negative. - The insulation was removed.
    In result, the temperature rise in general is physically to expect, naturally, by how much is quite uncertain.

    This leads to the conclusion that we have to search for the natural behaviour.
    If we want to know this and with it about the anthropogenic influence we have to know the natural equilibrium temperature at a comparable solar activity.
    Naturally means that we have Temp=Func(Sun, Albedo, Aerosols (incl. Clouds & Volcanoes)). So we have to search for times with similar conditions. The uncertainties lay in the amounts of albedo and aerosols because for former times we know little about. But we can certainly assume that the natural values might be similar.
    For the sun it means a similar activity level. Solanki tells that this happened at about 8000bp, other studies point it at 5000bp. But these times have one in common: in most studies / proxies they show a warmer climate than today.
    With this knowledge gained we are now able to amount the antropogenic influences and forcings, both the negative and, of course, the positive (GHG, antropogenic aerosols and changes in planetary albedo etc).

    One can conclude that we are not far away from the natural behaviour that could be expected. But it is necessary to broaden the view and put away the look at a cherry of only 35 years.
  47. JoeRG - There's excellent correlation between the sum of forcings and climate, more than just TSI. Just not (currently) between natural forcings and climate, since we've added such a huge anthropogenic forcing.

    I suggest you look at the IPCC discussion of this:

    Figure 9.5. Comparison between global mean surface temperature anomalies (°C) from observations (black) and AOGCM simulations forced with (a) both anthropogenic and natural forcings and (b) natural forcings only.

    The climate moved clearly away from a natural forcing response (TSI, volcanoes, etc) sometime mid-20th century.
  48. @KR

    You cannot deny that a well tuned, means a good model can predict everything wanted.
    Honestly, this IPCC model linked is a bad one.

    The only section that has a nearly proper correlation is the time after 1963 in the upper diagram (anthropogenics included).
    The other part, 1900 until 1963, does not fit at all. This is a mess, because this is the section to which the natural forcings have to be attuned. Neither in the upper nor in the lower diagram there are any signs of fitting the lower peak around 1910 or the higher peak in the 40th. So the predicted temperature curve is much too flat. As well, the effect of global dimming, widely accepted in science, is missing (the natural forces would have caused higher temperatures, countered by this effect).
    This is a clear sign of underestimated natural forcings in this model (both curves are almost identical in this time, so the anthropogenic forcings are negligible).
    One that claims to have a sceptic look at science must have recognized this - and, if I am right, most posters here claim it.

    Regrettably I have to conclude that it is not as you suggest that there would be an excellent correlation. Perhaps some kind of excellence in the part that is claimed to be important, but a mess in the offcut.

    Generally, models, even those accepted by the IPCC, do not always match the reality. You can of course use the models to get your conclusions, but how reliable can models be if the tuning sections don't fit at all?
  49. JoeRG

    I don't know if you are aware of this, but there are several issues with your comment.

    First is that natural variability means that on a short time scale (5-10 years) 'climate' models can only give an approximation of the 'weather', where on 20-30 years they do an excellent job of looking at trends. It's not a miss unless the observations go outside the envelope of model predictions, the orange and blue bands representing the multiple-run envelope.. Therefore the fit with anthropogenic forcings is quite good.

    Second, given recent higher grade measurements of forcings, the post 1950's fit is accordingly better in the models.

    Third, 'global dimming' shows up in both model and measurement data as change to a downward trend around 1940. I think your statement regarding that is unfounded.

    Finally, as to models - they are an important tool for teasing out the contributions and effects of different forcings, as well as a good check on our understanding of the physics involved.

    Based on our understanding of the physics of forcings, the measured changes in solar activity, volcanic activity, etc., natural forcings should have cooled the climate considerably since mid-century. That did not happen - anthropogenic forcings made the difference, hence current warming. So again, the statistically significant (obvious to the point of a boot to the head) break between natural forcings and climate response became visible mid-20th century.

    I suggest you read the Models are unreliable thread if you have such concerns about the use of models as tools.
  50. KR

    First is that natural variability means that on a short time scale (5-10 years) 'climate' models can only give an approximation of the 'weather', where on 20-30 years they do an excellent job of looking at trends. It's not a miss unless the observations go outside the envelope of model predictions, the orange and blue bands representing the multiple-run envelope.. Therefore the fit with anthropogenic forcings is quite good.
    If you didn't notice, the two peaks I mentioned are begin and end of a trend that lasted about 35 years and that, after removing the noise of ENSO effects, was as straight as a temperature trend could ever be. So I didn't speak about a short time effect but about a significant climatic scenario. Besides, it is a good example for underestimation of natural forcings, especially the solar forcing.
    Given that the forcings are to describe as a function like in comment #845 by scaddenp, the function for the natural forcings is: (nat)Temp = Func(Sun, Albedo(clouds), Aerosols(vulcans)). Looking at the conditions shows that in this period the albedo is to assume as nearly constant and the aerosols were slightly lowering with only a very small change after 1915. So the solar forcing remained as the main driver of the occured trend.
    As well, if only the natural forcings were considered, this trend should have been continued until 1963 because there were no significant changes.
    This leads to your next statement:
    Third, 'global dimming' shows up in both model and measurement data as change to a downward trend around 1940. I think your statement regarding that is unfounded.
    Excuse me, but where is it? In the measurements clearly, but where in the models?
    Given the circumstances that no natural forcing had changed that far that the trend could have been stopped (in the period from '45 until '63) results in the conclusion that anthropogenic forcings were at work in the manner of global dimming. This would mean that natural forcings must have caused higher temperatures as anthropogenic forcings in this time. But this never happens in the models.

    Summarized: We have a model that
    1) doesn't consider significant trends,
    2) underestimates natural forcings and
    3) shows wrong values of anthropogenic forcings.
    Sorry, but 'excellent' is something different.

    Finally, as to models - they are an important tool for teasing out the contributions and effects of different forcings, as well as a good check on our understanding of the physics involved.
    Such models give the impression that the physics are not well understood, at least in the climate science.

    Second, given recent higher grade measurements of forcings, the post 1950's fit is accordingly better in the models.
    Not quite. Forcings are calculated based on measured physical values and observed conditions.

    I suggest you read the Models are unreliable thread if you have such concerns about the use of models as tools.
    I didn't mean to go too far off topic, but this model that you've presented is a proper example for an analysis how underestimated solar activities are in the climate models.

    As I see it, because of false trails that exist (and that are powered by such bad models), the research in possible amplifications of solar forcings is too little to get a better understanding.
    For example, as I told before the magnetic field of the Earth weakened by 10% in the last century while the solar magnetic flux nearly doubled. I found only a view studies about this influence on climate, but most of them were made by persons that you would call a 'denier'. In the IPCC documents I found nothing at all, regrettably.
    As well, an influence of number and intensities of solar flares is possibe (and can of course explain the unusual hard rise in the OHC in 2003).
    But as long as only the last 35 years of solar activity are considered (as in the 3 topics and the IPCC reports) there will be probably no change in research.
    And that is not only a 'miss', it is truly a mess.

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