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Post by magellan on Sept 21, 2009 2:11:57 GMT
Oceanic Influences on Recent Continental Warmingtinyurl.com/5mr99fAbstract Evidence is presented that the recent worldwide land warming has occurred largely in response to a worldwide warming of the oceans rather than as a direct response to increasing greenhouse gases (GHGs) over land. Atmospheric model simulations of the last half-century with prescribed observed ocean temperature changes, but without prescribed GHG changes, account for most of the land warming. The oceanic influence has occurred through hydrodynamic-radiative teleconnections, primarily by moistening and warming the air over land and increasing the downward longwave radiation at the surface. The oceans may themselves have warmed from a combination of natural and anthropogenic influences.
Now glc and socold, is it too difficult to add 2+2 and end up with 4? Take the above paper and combine it with Shaviv, Lindzen and the most recent on amplification of solar radiation effects and what does that leave for CO2? About zero. Is the picture getting clearer now?
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Post by glc on Sept 21, 2009 9:00:54 GMT
First of all, Nautonnier suggests I read Shaviv. From the abstract, he quotes the following
"We find that the total radiative forcing associated with solar cycles variations is about 5 to 7 times larger than just those associated with the TSI variations, thus implying the necessary existence of an amplification mechanism, although without pointing to which one."
i.e. the TSI variation is amplified which implies a strong positive feedback and suggests HIGH climate sensitivity.
I responded by saying that the work by Lindzen and Spencer indicated negative feedback and LOW climate sensitivity. I questioned the sceptic stance on sensitivity.
Hunter then jumped in with this
“To assert a strong positive feedback climate is to believe in science fiction.”
Ok - does this that mean Shaviv's work is Science Fiction or what?
Magellan then asks me (and socold) to
Take the above paper [see below] and combine it with Shaviv, Lindzen and the most recent on amplification of solar radiation effects and what does that leave for CO2? About zero.
What?? Shaviv and Lindzen say completely different things. One implies high sensitivity the other low.
The “above paper” Magellan refers to includes the phrase “Atmospheric model simulations of the last half-century with prescribed observed ocean temperature changes…..”. So let me get this right. Can we use models or not? Or can we only use them when they give a result which supports our particular point of view.
But it gets better.
I’m forever being told that, due to thermal inertia, the temperature response to a change in solar forcing won’t be immediate. Apparently that’s why, even following a solar cycle of average activity and, despite a deep solar minimum, global temperatures are still higher than they were in the 1980s and 1990s when the more intense cycles occurred. No-one has yet pinpointed exactly what the time lag is but I notice it’s starting to get longer. But we can be sure that the effect is most definitely not immediate…..or can we….. Magellan has posted a graphic which shows that the response to TSI changes in the arctic is most definitely immediate. There is no lag whatsoever. The graph is, almost certainly, nonsense. If it weren’t it would be more widely distributed on sceptic sites. I can spot a few suspicious features. But the real point is that there is no consistency.
You people claim to be sceptics – but you’re not. You’re just the flip side of the AGW alarmists. Alarmists embrace anything which supports their belief which is no different to what happens on blogs such as this. True sceptics question everything – not just the results they don’t like.
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Post by jurinko on Sept 21, 2009 10:09:49 GMT
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Post by glc on Sept 21, 2009 12:38:42 GMT
But this is feedback and sensitivity to solar radiation, not to some trace atmospheric gas.From my post 7:26 pm Yesterday: Perhaps a change in solar forcing is different to other forcings. Is it ? If so - why is it? Possible amplifiers were described in recent work Meehl et al. www.ucar.edu/news/releases/2009/solarcycle2.jsp I don’t think your link answers the question. From the link we have the following An international team of scientists led by the National Center for Atmospheric Research (NCAR) used more than a century of weather observations and three powerful computer models…..So it is alright to use models, then. Do others agree? ….. to tackle one of the more difficult questions in meteorology: if the total energy that reaches Earth from the Sun varies by only 0.1 percent across the approximately 11-year solar cycle, how can such a small variation drive major changes in weather patterns on Earth?This is looking at how the ~11 year solar cycle might influence weather patterns. It does not suggest a mechanism for the sustained warming over the past several decades. I don’t believe that this, in any way, provides an explanation for 20th century climate fluctuations. If there is a cyclical process driving the climate (e.g. solar, ocean, whatever) then we should always end up roughly where we started. Now the argument is that, as well as the short term cycles (e.g. ENSO, Solar), there are longer term cycles which explain periods of long term warming (or cooling). But even if (a big if) the long term solar cycles exist there is less variation than over the 11 year cycle so the whole thing falls apart. In fact, it's now becoming apparent that solar output (TSI) has varied even less than previously thought over the past ~150 years. Most reconstructions (e.g Lean) significantly over-estimate solar variability. The solar link is in trouble.
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Post by magellan on Sept 21, 2009 13:39:13 GMT
First of all, Nautonnier suggests I read Shaviv. From the abstract, he quotes the following "We find that the total radiative forcing associated with solar cycles variations is about 5 to 7 times larger than just those associated with the TSI variations, thus implying the necessary existence of an amplification mechanism, although without pointing to which one."i.e. the TSI variation is amplified which implies a strong positive feedback and suggests HIGH climate sensitivity. I responded by saying that the work by Lindzen and Spencer indicated negative feedback and LOW climate sensitivity. I questioned the sceptic stance on sensitivity. Hunter then jumped in with this “To assert a strong positive feedback climate is to believe in science fiction.” Ok - does this that mean Shaviv's work is Science Fiction or what? Magellan then asks me (and socold) to Take the above paper [see below] and combine it with Shaviv, Lindzen and the most recent on amplification of solar radiation effects and what does that leave for CO2? About zero.What?? Shaviv and Lindzen say completely different things. One implies high sensitivity the other low. The “above paper” Magellan refers to includes the phrase “ Atmospheric model simulations of the last half-century with prescribed observed ocean temperature changes…..”. So let me get this right. Can we use models or not? Or can we only use them when they give a result which supports our particular point of view. But it gets better. I’m forever being told that, due to thermal inertia, the temperature response to a change in solar forcing won’t be immediate. Apparently that’s why, even following a solar cycle of average activity and, despite a deep solar minimum, global temperatures are still higher than they were in the 1980s and 1990s when the more intense cycles occurred. No-one has yet pinpointed exactly what the time lag is but I notice it’s starting to get longer. But we can be sure that the effect is most definitely not immediate…..or can we….. Magellan has posted a graphic which shows that the response to TSI changes in the arctic is most definitely immediate. There is no lag whatsoever. The graph is, almost certainly, nonsense. If it weren’t it would be more widely distributed on sceptic sites. I can spot a few suspicious features. But the real point is that there is no consistency. You people claim to be sceptics – but you’re not. You’re just the flip side of the AGW alarmists. Alarmists embrace anything which supports their belief which is no different to what happens on blogs such as this. True sceptics question everything – not just the results they don’t like. glc said: What?? Shaviv and Lindzen say completely different things. One implies high sensitivity the other low.
Nir Shaviv: On Climate Sensitivity and why it is probably smallwww.sciencebits.com/OnClimateSensitivity Shaviv's paper on oceans does not imply high climate sensitivity. You haven't the foggiest idea, and it is made obvious by the ignorant statement that Lindzen and Shaviv are contradictory. The oceans as a calorimeter www.sciencebits.com/calorimeterIf only solar irradiance is the cause of the solar-related climate variations, it would imply that the small solar variations cause large temperature variations on Earth, and therefore that Earth has a very sensitive climate. If on the other hand there is some amplification mechanism, it would imply that solar variations induce much larger variations in the radiative budget, and that the observed temperature variations can therefore be explained with a smaller climate sensitivity.
Magellan has posted a graphic which shows that the response to TSI changes in the arctic is most definitely immediate. There is no lag whatsoever. The graph is, almost certainly, nonsense. If it weren’t it would be more widely distributed on sceptic sites. I can spot a few suspicious features. But the real point is that there is no consistency. Ah yes, words of a "true skeptic" of AGW (caused by rising CO2 levels). The graph you say is nonsense is recent published material by Willie Soon. I have the articles, but you will need to do your own homework. Nonetheless, go ahead and bless us with your infinite knowledge and point out the suspicious features. It would also behoove you to read Tsonis on synchronized chaos.
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Post by radiant on Sept 21, 2009 14:08:03 GMT
The solar link is in trouble. If upper atmospheric chemistry is very important to the earth and UV radiation is currently reduced by 6% that seems pretty big to me. It is easily possible to imagine that a different chemistry or a different rate of change could create different minute solid particles in the atmosphere or changing amounts that return to earth to alter cloud formation rates. And apparently while the rest of the world is almost totally ignorant about the sun and it takes supposedly one million years for photons to move from the core of the sun to the surface and man has had the ability to observe the sun outside the atmosphere for about 50 years the solar link is in trouble.
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Post by glc on Sept 21, 2009 15:03:24 GMT
Shaviv's paper on oceans does not imply high climate sensitivity. You haven't the foggiest idea, and it is made obvious by the ignorant statement that Lindzen and Shaviv are contradictory.
This is from the Shaviv abstract
"We find that the total radiative forcing associated with solar cycles variations is about 5 to 7 times larger than just those associated with the TSI variations, thus implying the necessary existence of an amplification mechanism,
1. Does Shaviv suggest there might be an amplificatiom mechanism . There is a clue is there somewhere if you'd just look for it.
2. If there is an amplification mechanism - does this not suggest a positive feedback, i.e. in the sense that the resultant forcing is greater than that from TSI variation alone.
3. If there is a positive feedback - does this not suggest high climate sensitivity - or higher than no (or negative) feedback, at least. I'd suggest that an amplification factor of 5 is would be considered high sensitivity.
Shaviv is trying to have his cake and eat it. He is trying to argue that there is an amplification mechanism which operates independently of TSI (though in sync with TSI). He has no idea what this mechanism might be but he needs it to explain the magnitude of global temperature change. It's complete guff and you can't recognise it as such.
Re: the Soon rubbish.
As I said in the earlier post. No sceptic site - reputable or otherwise - has published this graph. There are a number of very good reasons for this. One of them being that Solar activity peak was in ~1958. The strongest cycle recorded was SC19 which ran from ~1954 until ~1964. The Soon plot suggests that average TSI over this entire cycle was ~1.5 w/m2 lower than other cycles. It's complete nonsense.
I have the TSI figures from a number of reconstructions as well as the PMOD and ACRIM figures. I've no idea where Soon gets his data but it's wrong.
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Post by icefisher on Sept 21, 2009 15:14:44 GMT
This is from the Shaviv abstract "We find that the total radiative forcing associated with solar cycles variations is about 5 to 7 times larger than just those associated with the TSI variations, thus implying the necessary existence of an amplification mechanism, 1. Does Shaviv suggest there might be an amplificatiom mechanism . There is a clue is there somewhere if you'd just look for it. 2. If there is an amplification mechanism - does this not suggest a positive feedback, i.e. that in the sense that the resultant forcing is greater than that from TSI variation alone. 3. If there is a positive feedback - does this not suggest high climate sensitivity - or higher than no (or negative) feedback, at least. I'd suggest that an amplification factor of 5 is would be considered high sensitivity. Seems to me GLC you are mixing metaphors above. Very clearly radiative forcing by definition is NOT a feedback. You say "the resultant forcing". Which implies to me you read it correctly but are just being stubborn. It appears clear to me the author is not venturing into the zone of trying to say what it is. . . .only you are. TSI's could be an indicator of a stronger force. Further Xrays into outer space blocking cosmic rays may be a feedback of the entire universal system. . . .but its incorrect to say such a feedback is an indicator of high climate sensitivity. As I pointed out one can invest too much baggage in ones nouns if one is not careful. Here you are very clear trying to take advantage of a confusion you are trying to invent and nobody is buying it.
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Post by glc on Sept 21, 2009 18:20:12 GMT
Seems to me GLC you are mixing metaphors above. Very clearly radiative forcing by definition is NOT a feedback.
Fine - then why doesn't Shaviv tell us what the "amplification mechanism" is. Shaviv is saying it's not a feedback because that implies high (very high) sensitivity. This means there must be a separate (from TSI) forcing which is 5-7 times larger than the TSI forcing. But we don't know what this other forcing is.
So how does Shaviv know that it's not a feedback effect? How, for that matter, does he know it's not an enhanced ghg effect.
Actually I 've just read your post again . In particualr - this bit
You say "the resultant forcing". Which implies to me you read it correctly but are just being stubborn. It appears clear to me the author is not venturing into the zone of trying to say what it is. . . .only you are
I don't disagree with this. The conclusion is that the study tells us very little. Magellan was wrong to bring it up.
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Post by glc on Sept 21, 2009 19:04:31 GMT
Re: The Soon graph posted by Magellan
The data used by Soon looks as though it might come from Doug Hoyt's old reconstruction. That's the closest match I can find.
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Post by socold on Sept 21, 2009 19:33:00 GMT
By the way, socold asserts the following: "Well that's a shame because many skeptics could benefit from understanding what things like climate sensitivity, climate feedbacks and radiative forcing are and the relationship between them. RealClimate is perhaps the only blog that explains these concepts nicely. These were all long ago posts, they've pretty much run through all those concepts by now." What a load of utter bs. RC is a propaganda site that exists to sell AGW. RC is not about climate science. RC is about AGW. Schmidt is to climate science what Elizabeth Sanger was to evolution. en.wikipedia.org/wiki/Margaret_SangerYou'll find a lot to learn from the early realclimate articles which explained modern climatology concepts such as radiative forcing, feedbacks, climate sensitivity, energy balance, etc. I know I found them very useful as that kind of information didn't exist anywhere else online at the time.
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Post by socold on Sept 21, 2009 19:53:46 GMT
Oceanic Influences on Recent Continental Warmingtinyurl.com/5mr99fAbstract Evidence is presented that the recent worldwide land warming has occurred largely in response to a worldwide warming of the oceans rather than as a direct response to increasing greenhouse gases (GHGs) over land. Atmospheric model simulations of the last half-century with prescribed observed ocean temperature changes, but without prescribed GHG changes, account for most of the land warming. The oceanic influence has occurred through hydrodynamic-radiative teleconnections, primarily by moistening and warming the air over land and increasing the downward longwave radiation at the surface. The oceans may themselves have warmed from a combination of natural and anthropogenic influences.
First of all I notice you are putting forward model based evidence, ie it's evidence that you don't accept. Second it doesn't diminish the role of co2, it's about the land warming being primarily driven by the ocean warming and we all know what the models say about the cause of that. Again of course you disagree. Furthermore notice they cite the warming response of moistening of the atmosphere over the land. Oh no that's the dreaded water vapor feedback. Of course again you will disagree. There's something darn odd about a person posting a paper that disagrees with their own view on multiple points. Here's two interesting papers: "“ The cyclic variation in the cosmic ray rate is observed to be delayed by 2–4 years relative to the temperature, the solar irradiance and daily sun spot variations suggesting that the origin of the correlation is more likely to be direct solar activity than cosmic rays. Assuming that the correlation is caused by such solar activity, we deduce that the maximum recent increase in the mean surface temperature of the Earth which can be ascribed to this activity is ~<14% of the observed global warming.”" www.iop.org/EJ/article/1748-9326/4/1/014006/erl9_1_014006.html"“A decrease in the globally averaged low level cloud cover, deduced from the ISCCP infrared data, as the cosmic ray intensity decreased during the solar cycle 22 was observed by two groups. The groups went on to hypothesize that the decrease in ionization due to cosmic rays causes the decrease in cloud cover, thereby explaining a large part of the currently observed global warming. We have examined this hypothesis to look for evidence to corroborate it. None has been found and so our conclusions are to doubt it. From the absence of corroborative evidence, we estimate that less than 23%, at the 95% confidence level, of the 11 year cycle change in the globally averaged cloud cover observed in solar cycle 22 is due to the change in the rate of ionization from the solar modulation of cosmic rays" www.iop.org/EJ/article/1748-9326/3/2/024001/erl8_2_024001.html[/QUOTE] You forgot one critical fact: Arctic and Global temperature trends are not the same. Therefore if solar activity correlates with the arctic temperature record it doesn't correlate with the global temperature record. In fact it looks like co2 correlates better with the global temperature record over the 20th century. Solar doesn't even really correlate well with arctic temperature in recent years. I am told by skeptics that the recent warm arctic datapoints have nothing to do with the loss of sea ice.. Maybe we should have a thread devoted to the divergence in arctic temperature vs solar activity in recent years.
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Post by socold on Sept 21, 2009 20:15:38 GMT
We have one group of skeptics claiming recent warming is due to reduced cloud cover caused by cosmic rays.
But we have a different group of skeptics claiming clouds respond to warming by increasing in cover therefore reducing any warming and acting as a strong negative feedback.
One group is relying on clouds to amplify a weak solar signal. While the other is relying on clouds to dampen warming.
Is this a contradiction? Im not certain but it doesn't on the face of it seem to make sense.
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Post by sigurdur on Sept 22, 2009 0:29:56 GMT
We have one group of skeptics claiming recent warming is due to reduced cloud cover caused by cosmic rays. But we have a different group of skeptics claiming clouds respond to warming by increasing in cover therefore reducing any warming and acting as a strong negative feedback. One group is relying on clouds to amplify a weak solar signal. While the other is relying on clouds to dampen warming. Is this a contradiction? Im not certain but it doesn't on the face of it seem to make sense. Yes it does Socold: It is called science. Both sides are open to arguement and need further research.
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Post by sigurdur on Sept 22, 2009 0:45:17 GMT
We have one group of skeptics claiming recent warming is due to reduced cloud cover caused by cosmic rays. But we have a different group of skeptics claiming clouds respond to warming by increasing in cover therefore reducing any warming and acting as a strong negative feedback. One group is relying on clouds to amplify a weak solar signal. While the other is relying on clouds to dampen warming. Is this a contradiction? Im not certain but it doesn't on the face of it seem to make sense. Yes it does Socold: It is called science. Both sides are open to arguement and need further research. Just as the AGW idea is open to arguement and needs further research. You are very quick to blame co2 for all sorts of things. Yet, upon examination of the literature, one can find radical climate shifts in the past that only took 30 years. And these shifts were warming and cooling...and no one really knows why. And looking at current temps, they are absolutely nothing new in the Halocene period. Even the rate of increase since the mid 1880's is nothing new in this period. I know you are in love with Mann's hockey stick, and so be it. There is so much evidence that his hockey stick is wrong that, as smart as you are, I can't believe that you are still hoodwinked by it. The main thing to understand in allllll of this is that when you are talking climate, you are not talking decades unless those decades are in a shift. Average climate is a slow moving beast, and the warming for the past 160-180 years only shows that it is warming, as it has done in the past, and it will cool, as it has done in the past. Co2 on every graph that I know off, and that is quit a few is a lagging indicator of temp. I know you will tell me Real Climate took care of that, and shows that it is mutual of temps, but one question that never got posted.....or I should say got posted but didn't get through the censors, was why does co2, in everyyyy period keep rising when the temp drops at the end of a warm period. That is a million dollar question is it not? IF co2 was such a strong driver, the temp should keep rising as it rises, but historically that is not the case. The temp peaks, co2 keeps climbing for 100's of years as the temp falls.
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