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Robbo the Yobbo at 18:19 PM on 22 July 2009Climate time lag
All I can suugest is that you take on the advice below. 'Thanks for the post Kyle. I hope you’re wrong though, because the thought of 10 more years of the deniers screaming (increasingly loudly) about how global warming is a bunch of not happening BS is a bit more than I for one can take. They could really use this to very damaging political advantage, weakening proactive action just when it’s most needed.' [Response: When the Keenlyside paper came out, Andy Revkin had a nice blog article on whether the drive for carbon mitigation action could survive (another) decadal interruption in warming. It's a good question, but one I wouldn't presume to know how to answer. Our best armory for the arguments you fear quite rightly is to build up our understanding of decadal variability and the extent to which it can cloud the long term trend. It's too soon to say whether the current "pause" in warming is anything more than statistics being clouded by one unusual El Nino event, but we should be thinking now about possible explanations just in case something more interesting is going on. --raypierre] -
Robbo the Yobbo at 18:08 PM on 22 July 2009Climate time lag
Oh I remember - I got to: save gaia says: 12 Jul 2009 at 5:27 pm Maybe this annomaly you speak of has something todo with the montreal protocol? http://en.m.wikipedia.org/wiki/File:Ozone_cfc_trends.png and gave up. -
Robbo the Yobbo at 18:01 PM on 22 July 2009Climate time lag
No - I gave up on the thread - it was appallingly silly. Did you read the paper? "'realclimate' are now saying T will level off over the next decade or so". Um, no, they are not. One guest paper by two academics have suggested that the well known El NIn-La Nina cycling might, in 1998 have caused an even bigger jump than predicted from CO2 alone, and that there will be a discontinuity until the effects of greenhouse essentially catch up to where they would have been anyway." Perhaps not - because the level of understanding exhibited is entirely inadequate. The paper excluded sudden climate shifts and calculated a residual warming from all other causes of 0.1 degrees centigrade/decade. To my knowledge, no one has ever claimed that temperature didn't increase in the 20th century. There may be a farmer in Woop Woop - but look at it this way - he is still as right as you. -
Robbo the Yobbo at 17:59 PM on 22 July 2009Climate time lag
No - I gave up on the thread - it was appallingly silly. Did you read the paper? "'realclimate' are now saying T will level off over the next decade or so". Um, no, they are not. One guest paper by two academics have suggested that the well known El NIn-La Nina cycling might, in 1998 have caused an even bigger jump than predicted from CO2 alone, and that there will be a discontinuity until the effects of greenhouse essentially catch up to where they would have been anyway." Perhaps not - because the level of understanding exhibited is entirely inadequate. The paper excluded sudden climate shifts and calculated a residual warming from all other causes of 0.1 degrees centigrade/decade. To my knowledge, no one has ever claimed that temperature didn't increase in the 20th century. There may be a farmer in Woop Woop - but look at it this way - he is still as right as you. -
David Horton at 16:58 PM on 22 July 2009Climate time lag
Which part of "superimposed upon an overall warming presumably due to increasing greenhouse gasses" did you not understand? And yes, I did read the guest blog, written, as you know, by Kyle Swanson, as a summary and explanation of the Swanson-Tsonis paper. And the thread. Did you? -
Robbo the Yobbo at 16:35 PM on 22 July 2009Climate time lag
I was obviously optimistic to think that people would read the paper before rejecting it. It's OK David, just read the 'guest blog' and the posts - it won't challenge your preconceptions. -
Robbo the Yobbo at 16:20 PM on 22 July 2009Climate time lag
Sorry - is it the squid that are getting bigger because of global warming or the sheep that are getting smaller? Must be all that CO2 snow. I think the Swanson and Tsonis paper says that the recent rate of warming (between 1977 and 1997) is 0.1 degrees centigrade per decade from all other causes when the points of rapid climate shift are excluded – and that there will be no warming trend for the next decade or so. I made no other argument – simply that in my value judgement, 0.1 of warming between 1977 and 1997 from whatever cause, and there are many, is insufficient justification for continued global warming silliness. The 50 year modulation of ENSO is involved but so are modes of major climate variability. The Swanson and Tsonis paper uses coupled climate parameters - ENSO, the Pacific Decadal Oscillation, the North Atlantic Oscillation, and the North Pacific Index – and postulates that when these modes of major climate variability resonate, or are ‘synchonised’, the ‘character of ENSO variability’ is changed for 2 or 3 decades with a break in the ‘the global mean temperature trend’. They say that clouds may be involved. Acknowledging the limited cloud data available from the ISCCP – it is a possibility for the latest climate shift in 2001/2002. Swanson and Tsonis are recognising an underlying physical reality. The ‘modes of climate variability’ are real, quantified and, as I say, not simply the 2 to 7 year ENSO variation. ‘Extension of this analysis to the entire 20th century as shown in the bottom panel of Figure 1 reveals three climate shifts marked by breaks in the temperature trend with respect to time, superimposed upon an overall warming presumably due to increasing greenhouse gasses. Global mean temperature decreased prior to World War I, increased during the 1920s and 1930s, decreased from the 1940s to 1976/77, and as noted above increased from that point to the end of the century. Insofar as the global mean temperature is controlled by the net top-of-the-atmosphere radiative budget [IPCC 2007], such breaks in temperature trends imply discontinuities in that budget. Such discontinuities are difficult to reconcile with the presumed smooth evolution of anthropogenic greenhouse gas and aerosol radiative forcing with respect to time [Hansen et al. 2005]. This suggests that an internal reorganization of the climate system may underlie such shifts [Zhang et al. 2007]. And ‘However, the nature of these past shifts in climate state suggests the possibility of near constant temperature lasting a decade or more into the future must at least be entertained. The apparent lack of a proximate cause behind the halt in warming post 2001/02 challenges our understanding of the climate system, specifically the physical reasoning and causal links between longer time-scale modes of internal climate variability and the impact of such modes upon global temperature.’ I take it you will entertain the idea, reject it and accuse me of being psychologically aberrant. You might try these for a little background – I suggest that you take your time because real understanding comes from a considered and balanced approach. http://www.aoml.noaa.gov/phod/docs/ETPacInterdecadal.pdf http://climate.gi.alaska.edu/researchprojects/pages/AKpaper10.html -
David Horton at 16:10 PM on 22 July 2009Climate time lag
#159 Look thingy, that kind of stuff goes down well in talk back radio, or on the letters page of "The Australian", or at a branch meeting of the National Party, but your in the wrong venue here. "not even examine solar effects and solar heat lag" - two different things, as you must know. Solar effects (and I assume you are including Milankovitch cycles here) are well known, taken seriously, included in all models, account for some climatic changes in the past and present. never any dispute about that, much as you might try to mislead people. "Solar heat lag" as an explanation of current warming is, on the other hand, nonsense. John's original post points this out, and a number of us have responded on this thread. But I'll bet you keep saying it and keep writing it endlessly into the future, each time pretending it is a new idea never considered, Nobel Prize winning research. "'realclimate' are now saying T will level off over the next decade or so". Um, no, they are not. One guest paper by two academics have suggested that the well known El NIn-La Nina cycling might, in 1998 have caused an even bigger jump than predicted from CO2 alone, and that there will be a discontinuity until the effects of greenhouse essentially catch up to where they would have been anyway. It's just a hypothesis, considering the very big jump in 1998. I don't think it's correct, nor do many of the posters on the very long thread that follows (read that have you, thought about it?), but in any case it has absolutely no bearing, as the authors say, on the inevitable CO2 induced warming. To pretend that it does (or that warming has somehow stopped in the last decade) is denialist dishonesty of the most obvious kind. You might say it is "discouraging rational inquiry". And a concern for the future of the planet (last time I looked, the only one for miles around suitable for my grandchildren to live on) is a "greenie rant"? So be it. -
thingadonta at 15:59 PM on 22 July 2009Climate time lag
"That people like you or thinga with his obsession on transposing the diurnal "heat lag" to a larger scale would try to give lessons in assessing the science is, well, ironic". Transposing scale in natural systems is very common-eg from atomic to mesoscopic (eg crystal structure), eg fractal geometry, eg diurnal to annual, annual to decadal, and so on. In my field we use the term 'bonzai'-when comparing features of the very small to the very large. It is a very common scientific practice. But of course my field isn't strictly 'climate science', so it isn't relevant... There are numerous examples of scale correlations, and lag effects in nature, so I don't know what bee is in your bonnet about it, but one of the reasons I bring lag effects up is because some academics/ideologists tend to hate/miss the idea of a lag effect, because they can't directly 'match' causes and effects, which means they can't easily reduce innate variation down to their preferred mantra. It is the same reason historically that various ideologists tended to hate the idea of Einsteins relativity when it came out -it produces a mismatch between ideology, causes-effects, and general perspective. -
thingadonta at 15:40 PM on 22 July 2009Climate time lag
re150: Ideology attempts to place everything within the same set of related ideas and reduce inherant uncertainty, chaos and variation; it always takes the same side where there is fundamental ambiguity, and it usually suits vested interests-call them banks, academics, greens or whatever. Another feature of ideology is over-confidence, another suppression of valid dissent etc etc. To not even examine solar effects and solar heat lag on the 'energy imbalance' in Hansen 2005 reveals an ideological stance. Or even better, an 'ideological imbalance'. You could argue that I have a solar ideological bent, but with good reason, the sun tends to completely dominate earth climate variation historically/geologically, there is no reason this should suddenly cease in the last few centuries. Your c02 and general greenie-rant is a good example of an ideological stance. Pity you can't see it, but that's the nature of extreme ideology-it denies its own existance, or in Dawkins words-the ideology/meme complex secures its own perpuation by discouraging rational inquiry. But getting back to the topic, because the earth is not warming quite fast enough, 'realclimate' are now saying T will level off over the next decade or so. (Perhaps they have secretly taken a look at the sun lately-like KGB agents secretly trying to figure out why the capitalist system works so well). -
Philippe Chantreau at 14:22 PM on 22 July 2009Climate time lag
Boy that Yobbo is a horse that can talk. And that carbonic snow cone, you'll have it chocolate or vanilla? LOL. Oh, I forget, it's so darn cold in Vostok. That people like you or thinga with his obsession on transposing the diurnal "heat lag" to a larger scale would try to give lessons in assessing the science is, well, ironic. -
David Horton at 14:02 PM on 22 July 2009Climate time lag
#151 Silly me, so it's the CO2 ideology that says you can burn all of the carbon sequestered underground for millions of years and pump all that extra CO2 into the air while having no effect on the climate, while minor changes, up and down, in the sun, and which, conveniently, we can do nothing about, account for whatever climate change we have seen in the last 50 years. Oh and you might want to re-read the RC paper on "warming interrupted", and the discussion which follows. It doesn't say what you think it says, and in any case you do know it's an hypothesis and has nothing to do with solar variation, don't you? You did read the sentence "it’s important to note that we are not talking about global cooling, just a pause in warming" didn't you? You do know that this is just a variation on the already well known effect of El NIno-La NIna variation on the long term rise and rise in emissions-caused general global warming, don't you? I certainly wouldn't call you an egghead. -
Robbo the Yobbo at 13:15 PM on 22 July 2009Climate time lag
Pseudo egghead? I resent the implication that I'm not a real egghead. You really should spend some time on the science before leaping into the fray. The realclimate dicussion is here: http://www.realclimate.org/index.php/archives/2009/07/warminginterrupted-much-ado-about-natural-variability/ And the Swanson and Tsonis paper is here. http://www.uwm.edu/~kswanson/publications/2008GL037022_all.pdf -
Robbo the Yobbo at 13:11 PM on 22 July 2009Climate time lag
Pseudo egghead? I resent the implication that I'm not a real egghead. You really should spend some time on the science before leaping into the fray. The realclimate dicussion is here: http://www.realclimate.org/index.php/archives/2009/07/warminginterrupted-much-ado-about-natural-variability/ And the Swanson and Tsonis paper is here. http://www.uwm.edu/~kswanson/publications/2008GL037022_all.pdf -
Lee Grable at 13:06 PM on 22 July 2009Climate time lag
It's actually 9:00 PM on July 21st. I know, non relevant. -
Lee Grable at 12:33 PM on 22 July 2009Climate time lag
Get a life for crying out loud!!!! -
Lee Grable at 12:30 PM on 22 July 2009Climate time lag
When I first came across his website, I was excited. "Finally, I've found someplace that really examined the "skeptic arguement", I.E,the tactics they used to maintain the illusion of a debate. What I ended up finding was a place where a bunch of psuedo eggheads congregate to impress themselves and each other with how smart they sound. What a waste of cyberspace! -
Robbo the Yobbo at 12:28 PM on 22 July 2009Climate time lag
I think it might be the ideology of ocean acidification is 10 times worse than calculated, the ideology of an ice free Arctic by 2010, the ideology of 7m sea level rise by the end of the century, the ideology of a few pairs of breeding humans surviving in Antarctica by 2100. It is an ideology that not even a failure of the oceans to continue to warm (at a minimum) and falling surface temperatures cannot dent. It is the ideology that argues that the planet is still warming. It is an ideology that prefers GISSTEMP over HADCRU because GISSTEMP includes some marginal arctic stations but refuses to countenance the independent UAH or RSS satellite methods because they are showing less warming. It is an ideology that says that any exaggeration is responsible if it scares people into acting, any action is moral if it advances the cause and any opposition is evil and corrupt. This is an ideology that fails to recognise obvious 50 year climate cycles in global temperature, fisheries, sea surface temperature, Arctic temperature, rainfall, North American temperature etc. Not even last week’s effort on realclimate can put a dent in their confidence. Let me repeat the message of realclimate – no warming trend for 20 to 30 years (i.e. a 25 year cooling phase) from 2001/2002 and a background warming of 0.1 degree C/decade from all other factors. We are in a cooling trend and it will continue for a decade or 2 more. There is a trend of temperature increase of bugger all (an Australian technical term) in the UAH globally and depth average lower troposphere temperature. A value judgement – a trend of 0.10C/decade in temperature rature is insufficient to justify all of the present silliness and outright perverse self righteousness of Co2 ideology. -
David Horton at 10:15 AM on 22 July 2009Climate time lag
#147 - well, there's a new one "CO2 ideology". I wonder what that could be? Is it the ideology that shows, from physical principles, that CO2 is a greenhouse gas: or could it be the ideology that shows CO2 levels increasing? Or the ideology that shows, from the isotope signature, that the increase comes from human use of fossil fuels? Or perhaps the chemistry ideology that shows increasing ocean acidity as usual buffering effect of the oceans starts to be overwhelmed by the speed of increase in CO2? Or could it be the ecological ideology that finds rapid changes in the behaviour and distributions of animal and plant species? Or the ice ideology that measures the reduction in glacier lengths and ice cap volumes? So much ideology, so little science eh? Or am I thinking of the opposition? -
Lee Grable at 02:36 AM on 22 July 2009Climate time lag
This is just like the huffpost, except with bigger, fancier words. -
shawnhet at 01:51 AM on 22 July 2009Climate time lag
Chris: ""Phenomena do not typically have long-term with one another when there is not some causal connection" But we've already seen that this simply isn't true for the very phenomenon we've been discussing. A large set of analyses described in my post #71 indicates that any correlation between CRF and climate-related influences (low level clouds) is NOT causal, and is an artefact of the correlation of the CRF with the solar cycle, components of which DO correlate with the effect." The fact is that at best, the only thing that has been disproved is *one particular interaction of CRF* with climate. Further, as I have already mentioned, climate science is very complex, and what appears true today is not necessarily so(adjustments to climate data are pretty common). Finally, there is no inherent reason why short term "weather" fluctuations might not obscure a CRF signal, that might become clearer over the long-term. Fundamentally, what is clear is that there must be some sort of solar amplification to climate, and we don't know what it is yet. Also, be advised that there are yet other lines of evidence(that we haven't talked about yet) for CRF-climate links which detail climate fluctuations for periods when the relationship btw CRF and solar irradiance is known to be altered. "I'm happy to leave it there until evidence accrues that allows us to make more detailed causal interpretations of Holocene N. hemisphere climate variability. I have no problem with accepting uncertainty where this exists - what we certainly don't do is to introduce Kirkby-style "catch all fill-in-the-blanks type mechanisms" to "fill in" uncertainty, particularly when the causality associated with the mechanism is increasingly found to be suspect." Yes, I think that if you agree that there is some form of solar amplification, we aren't that far apart. You are missing the point of the Kirkby paper, though. It is saying that the CRF-climate interaction is worth studying precisely because it appears such an unknown amplification that CRF can help fill. Cheers, :) -
thingadonta at 22:52 PM on 21 July 2009Climate time lag
re: 144 David Horton This is a quote from the press release from Hansen himself, about Hansens et al's 2005 paper on the so-called energy imbalance: "the climate system is now being pushed so hard that I have suggested that we can say with confidence that 2005 will have a warmth comparable to that of 1998, and the remarkable 1998 global temperature record will soon be broken, if not this year than within the next several years.)," (http://junkscience.com/Greenhouse/imbalance_release.pdf) Note: the years from and including 2005 were not 'record breakers'. Also, ocean T has flattened or cooled since the early 2000s. His 'energy imbalance', supposedly driven by c02, is just not working. The cause(s) of the 'energy imbalance' in the paper of Hansen et al 2005,(if the 'energy imbalance' is indeed real-which it may not be), NEVER took into account the possibility that oceans have been heating from 1955-1998 in line with a solar heat lag effect from the solar peak in the 20th century, he simply assumes ocean heat is being driven by c02/greenhouse gases. He checks this with 'models', no models have been run regarding solar heat lag, clouds etc. However, it could equally be a confirmation of the solar heat lag one would expect from the mid 20th century-that is- there seems to be nothing 'driving' the heat in the oceans when modelled with the energy (apparently) leaving the atmosphere. Hansen et al 2005 never even investigate or consider thispossibility, because they are so bound up with c02 modelling and ideology. The years since this paper, 2005, have also invalidated his alarmist predictions above, and if the solar heat lag alternative theory is correct (or a version of it), there is no '0.6C warming left in the pipeline', since the sun is now waning, as is T. -
thingadonta at 22:47 PM on 21 July 2009Climate time lag
re: 144 David Horton This is a quote from the press release from Hansen himself, about Hansens et al's 2005 paper on the so-called energy imbalance: "the climate system is now being pushed so hard that I have suggested that we can say with confidence that 2005 will have a warmth comparable to that of 1998, and the remarkable 1998 global temperature record will soon be broken, if not this year than within the next several years.)," (http://junkscience.com/Greenhouse/imbalance_release.pdf) Note: the years from and including 2005 were not 'record breakers'. Also, ocean T has flattened or cooled since the early 2000s. His 'energy imbalance', supposedly driven by c02, is just not working. The cause(s) of the 'energy imbalance' in the paper of Hansen et al 2005,(if the 'energy imbalance' is indeed real-which it may not be), NEVER took into account the possibility that oceans have been heating from 1955-1998 in line with a solar heat lag effect from the solar peak in the 20th century, he simply assumes ocean heat is being driven by c02/greenhouse gases. He checks this with 'models', no models have been run regarding solar heat lag, clouds etc. However, it could equally be a confirmation of the solar heat lag one would expect from the mid 20th century-that is- there seems to be nothing 'driving' the heat in the oceans when modelled with the energy (apparently) leaving the atmosphere. Hansen et al 2005 never even investigate or consider thispossibility, because they are so bound up with c02 modelling and ideology. The years since this paper, 2005, have also invalidated his alarmist predictions above, and if the solar heat lag alternative theory is correct (or a version of it), there is no '0.6C warming left in the pipeline', since the sun is now waning, as is T. -
thingadonta at 22:06 PM on 21 July 2009Climate time lag
re: 144 David Horton This is a quote from the press release from Hansen himself, about Hansens et al's 2005 paper on the so-called energy imbalance: "the climate system is now being pushed so hard that I have suggested that we can say with confidence that 2005 will have a warmth comparable to that of 1998, and the remarkable 1998 global temperature record will soon be broken, if not this year than within the next several years.)," (http://junkscience.com/Greenhouse/imbalance_release.pdf) Note: the years from and including 2005 were not 'record breakers'. Also, ocean T has flattened or cooled since the early 2000s. His 'energy imbalance', supposedly driven by c02, is just not working. The cause(s) of the 'energy imbalance' in the paper of Hansen et al 2005,(if the 'energy imbalance' is indeed real-which it may not be), NEVER took into account the possibility that oceans have been heating from 1955-1998 in line with a solar heat lag effect from the solar peak in the 20th century, he simply assumes ocean heat is being driven by c02/greenhouse gases. He checks this with 'models', no models have been run regarding solar heat lag, clouds etc. However, it could equally be a confirmation of the solar heat lag one would expect from the mid 20th century-that is- there seems to be nothing 'driving' the heat in the oceans when modelled with the energy (apparently) leaving the atmosphere. Hansen et al 2005 never even investigate or consider thispossibility, because they are so bound up with c02 modelling and ideology. The years since this paper, 2005, have also invalidated his alarmist predictions above, and if the solar heat lag alternative theory is correct (or a version of it), there is no '0.6C warming left in the pipeline', since the sun is now waning, as is T. -
David Horton at 21:32 PM on 21 July 2009Climate time lag
John - time you stepped in again. Your attempt to set the record straight (so to speak) on "heat lag" has made the heat lag obsessives even more so. It is a theory that can't be falsified, because you simply choose whichever time lag will allow a close match with your non-cause. -
thingadonta at 17:14 PM on 21 July 2009Climate time lag
Things (so far) that a solar heat lag of ~40-60 years explains: -the so called "energy imbalance" of Hansen 2005-ie why the oceans have heated up to the early 2000s, in apparent imbalance with air T and heat flux(Hansen et al don't bother examining solar heat lag to explain this ocean warming 1955-1998). -ocean heat flat-lining since the early 2000s. (ie: its after 2:30pm on any average day now) -air T flat lining since early 2000s (same as above) -flattening sea levels in last few years -increasing T since ~1980, despite no apparent increase in solar activity (heat lag effect) -sun slowly waning yet no marked decrease in T yet, only flat-lining (heat lag effect) -inability of c02 theorists to recognise heat lag effect since one can't easily match immediate causes and effects (which academics are generally trained to do). -possibly delayed low cloud cover after solar peak is reached, excaberting T in late 20th Century, particularly in temperate zones with less low cloud cover (closer to condensation point, and cosmic rays). -not examined or even thought of by Gore, Hansen and co because doesnt fit c02 ideology. Prediction: T flat lines and then wanes from early 2000s-2020+, as opposed to Hansen's 2005 prediction of "record breaking years" within 3-4 years after 2005 by his so called 'energy imbalance' (already invalidated)-which is just a solar heat lag effect. -
Robbo the Yobbo at 16:49 PM on 21 July 2009Climate time lag
There is an amount of energy called the enthalpy of fusion. In the ice/liquid phase transition – the energy from the atmosphere or ocean used to melt ice is internalised as kinetic energy. This energy is ‘hidden’ but it is not sufficient to make a huge difference to global energy budgets. Melting ice may cause oceans to be cooler – just like the ice in your glass. Ocean temperature is measured but the calculated heat content of the ocean is the important metric. Just like the total heat in an insulated container containing ice and water doesn’t change rapidly – although the enthalpy of fusion may be significant on that scale. The total heat content of the planet doesn’t change as a result of melting ice other than with the minor enthalpy change noted. It is no great mystery why the ocean is not warming at the anticipated rate – or while the atmosphere is cooling at the same time. http://bbso.njit.edu/Research/EarthShine/literature/Palle_etal_2008_JGR.pdf There has been a decrease in shortwave forcing since 1998 of 2 W/m2. Earth albedo was at a minimum in 1998 and has increased since. Both low level and high level cloud decreased to 1998 and increased thereafter in the climatically important equatorial zone. I am inclined to accept the Usoskin’s correlation of cosmogenic isotopes – over 1150 years. A correlation against global and hemispheric reconstructions of temperature. I am inclined to accept as plausible the mooted mechanisms of a cosmic radiation cloud connection. The experiment evidence in the SKY experiment is intriguing. I am inclined to think that there is a correlation of the aa geomagnetic index with 20th century temperature as below. The question is – is the cloud response characteristic of 20 to 30 year climate cycles found everywhere in the climate record? Not enough cloud data. But the cycles remain – adding to temperatures in the warming phase of 1976 to 1998 and masking warming since. In the current cool phase - there appears to be a cloud connection. The regularity of phase changes suggests that we are looking for a cyclic phenomenon. http://academicjournals.org/ijps/PDF/Pdf2006/Oct/El-Borie%20and%20Al-Thoyaib.pdf Can we use the aa geomagnetic activity index to predict partially the variability in global mean temperatures? M.A. El-Borie1 and S.S. Al-Thoyaib2 1 Physics Department, Faculty of Science, Alexandria University, Alexandria, Egypt. 2 Physics Department, Al- Rass Teacher’s College, Al-Qaseem, K.S.A. Accepted 17 October, 2006. Data for geomagnetic activity index aa and solar sunspot number Rz for 1868-2004 were subjected to correlation analysis with the global surface temperature (GST). The annual-means GT show that it had two warming phases and one cooling period. Observations of the Earth's near-surface temperature showed a global-mean temperature increase of approximately 1.1° C since 1877, occurred from 1887 to 1940 and from 1970 to the 1998. The temperature change over the past 35 years (1970-2004) is unlikely to be entirely due to internal climate variability. Attribution of the warming early in the century has proved more elusive. The correlation analysis between the variation of global temperature and both aa geomagnetics and solar activity are +0.5 ± 0.05, for any lag or lead, indicating a significant role in such variation. All graphs have illustrated strong correlations between the solar activity and geomagnetics and surface global temperature. Our results do not, by any means, rule out the existence of important links between solar activity and terrestrial climate. Our results displayed that the present changes in aa geomagnetics may reflect partially some future changes in the global surface temperatures. Key words: Geomagnetic induction, Atmospheric sciences, Climatology, Climate and interannual variability. -
thingadonta at 11:58 AM on 21 July 2009Climate time lag
#130 - "Now that the oceans T appear to be flattening and cooling since early 2000s " How many cubic miles of land ice are running into the oceans as ice-cold water in recent years? Has this number been increasing? Wouldn't this have some effect on ocean temps in the same way adding ice to your drink will cool your drink. No this doesnt work with the volumes involved. If you warm a cup of water with ice in it, the ice melts but does not cool the water overall, as the water is also warming when you warm the cup. The ice can only cool the water if there is a very large ice/water differential with poor heat transfer, which is not the case here-there is a large ocean/ice differential. The oceans are cooling because the sun is now waning. c02 has no effect on ocean T. -
chris at 09:27 AM on 21 July 2009Climate time lag
"Phenomena do not typically have long-term with one another when there is not some causal connection" But we've already seen that this simply isn't true for the very phenomenon we've been discussing. A large set of analyses described in my post #71 indicates that any correlation between CRF and climate-related influences (low level clouds) is NOT causal, and is an artefact of the correlation of the CRF with the solar cycle, components of which DO correlate with the effect. That could hardly be plainer. We don't choose the "simplest theory possible" if the theory is incompatible with the evidence. We know that the CRF generally varies in line with solar outputs (whether or not there is a strict linear relationship) and in very many studies is used as a proxy for solar output variation. We can hardly assert that changes in solar irradiance are insufficient to account for the phenomenon observed if we don't (a) have a measure of the solar irradiance contemporaneous with the phenomenon of interest and (b) have a good handle on the magnitude of solar irradiance required to influence the phenomenon. I don't see any point in introducing "catch all fill-in-the-blanks type mechanisms" as pseudo-explanations (CRF) when the evidence doesn't support these. What we do have is abundant evidence that ocean/atmosphere circulation changes are associated with much of the variation in high Northern latitude climate variation through the Holocene. We can accept that (heat transfer variations) as a fundamental proximate cause of temperature proxies observed since the evidence is very strong. We don't have to postulate global scale phenomena since the evidence doesn't support this. We don't understand the ultimate causes of the circulation changes very well- these do seem to have a solar component for Bond cycles observed in the Northern latitudes. The evidence indicates that this isn't due to the CRF component of the solar influence. Where we do have some evidence (MWP/LIA) this is likely solar irradiance/volcanic sea surface temperature influences (see Trouet et al, 2009 cited above, for example). I'm happy to leave it there until evidence accrues that allows us to make more detailed causal interpretations of Holocene N. hemisphere climate variability. I have no problem with accepting uncertainty where this exists - what we certainly don't do is to introduce Kirkby-style "catch all fill-in-the-blanks type mechanisms" to "fill in" uncertainty, particularly when the causality associated with the mechanism is increasingly found to be suspect. -
shawnhet at 08:50 AM on 21 July 2009Climate time lag
Chris: "That's a self-contradictory assertion. It contradicts the essential basis of scientific understanding namely . We've already seen that there is abundant evidence for THC contributions (Lund et al, 2006; Denton and Broecker, 2008; Trouet et al, 2009; see Thornalley et al 2009 below) to the events we've been discussing; we could cite much more of this. You reject it without giving any evidence." My point is that saying that THC changes are responsible for something when we don't know what causes the THC to change is simply begging the question. I think THC is a symptom of climate "fundamentals", not properly the cause of them. For you to simply accept that the THC causes climate change without understanding what causes the THC is not "supporting fundamental interpretations". ""I don't know enough about the Bond effects to consider causality in detail, but I'd be very interested to see what scientific analysis informs your views on this. In the meantime, I'm prepared to accept Bond's interpretation of solar forcing with some potenial THC amplification. Since we don't know the magnitude of solar irradiance contemporaneous with these events we can hardly assert that this was not sufficient to mediate these phenomena. Your either this/either that binary choice is non-scientific, since it pre-selects for interpretations that are not necessarily consistent with the evidence. For example, it's quite possible that the Bond events report changes in heat transport through variations in thermohaline circulation that predominantly affect the high Northern latitudes. That's consistent with much of the science I've already cited (including Bond et al 2001) as well as additional recent evidence for Holocene oscillations in North Atlantic heat and salinity driven by variations in the THC [*], and observations that the events observed in the High Northern latitudes (Bond events, MWP; LIA) generally don't have deep Southern Hemisphere correlates [**] " First off, if THC is the result of an amplification of some sort then THC-forcing is simply an indirect solar forcing. Secondly, the large climate events correlate to CRF, so if the magnitude of CRF doesn't correlate with the magnitude of irradiance, then that is good evidence that CRF *on its own* has climate impact. You call this either-or science, I call it simple logic. Phenomena do not typically have long-term with one another when there is not some causal connection. I think it is always preferable to have the simplest theory possible. Cheers, :) -
chris at 08:26 AM on 21 July 2009Climate time lag
whoops, I left out a word: My first two sentences should read: That's a self-contradictory assertion. It contradicts the essential basis of scientific understanding evidence. -
chris at 08:22 AM on 21 July 2009Climate time lag
"I don't really want to get into the reasons why THC based explanations aren't very good IMO. That is a whole other line of argument. I don't really have a fundamental problem with them as *response* to long-term solar heating, I suppose. It is simply with them as a catch all fill-in-the-blanks type mechanism, I object to." That's a self-contradictory assertion. It contradicts the essential basis of scientific understanding namely -
shawnhet at 06:05 AM on 21 July 2009Climate time lag
What Bond et al. are rather clear on is the correlation btw solar events and climate ones and the magnitudes thereof. They don't mention CRF, of course, (and I never said they did), but they do say such things as "Our correlations are evidence, therefore, that over the last 12,000 years virtually every centennial time scale increase in drift ice documented in our North Atlantic records was tied to a distinct interval of variable and, overall, reduced solar output." They provide various possible amplifiers for solar input, because solar input alone doesn't work. Obviously, CRF climate interactions are one possible solar amplifier. "Think about it. Your assertion requires that you know the magnitiude of the irradiance changes contemporaneous with the events. We've been talking about contributions from irradiance changes (0.2 oC's worth) during a period where there's a reliable reconstruction (Lean et al back to the Maunder Minimum). Do you know what the irradiance values were further back in the Holocene? I don't think so…" There are two options here. Either the magnitude of solar irradiance has a (more or less) constant relationship to the level of CRF fluctuations or it does not. If the first case is true, then the pattern of climate fluctuations to the solar proxies implies that there is an amplifying agent, which is why Bond et al. proposes some. If, OTOH, the magnitude of solar changes is not constant wrt CRF changes then there is no reason why the correlations that Bond et al find should exist at all. IAC, perhaps we are making headway here - do you agree with Bond et al. that some sort of solar amplification is likely? I don't think we have enough evidence to tell what the nature of the solar amplification is, but we do IMO have enough to tell us that one does exist. I don't really want to get into the reasons why THC based explanations aren't very good IMO. That is a whole other line of argument. I don't really have a fundamental problem with them as *response* to long-term solar heating, I suppose. It is simply with them as a catch all fill-in-the-blanks type mechanism, I object to. Cheers, :) -
chris at 04:56 AM on 21 July 2009Climate time lag
I've read Bond et al shawnet. I was referring to some research published in the intervening period based on research that isn't nearly 10 years old. Your idea that research fields can be fully defined by recourse to single papers or dodgy reviews is not going to give you much insight into these difficult subjects! Note that you've mis-interpreted Bond et al who are rather consistent with the evidence from the pukka science that I've been discussing, and makes no mention of any CRF effects. In fact Bond et al interpret their data in terms of solar irradiance changes, amplified by thermohaline circulation effects:"Each of those episodes also corresponds to paired intervals of reduced solar irradiance and increases in North Atlantic ice drift in our records" and: "Results of recent atmospheric general circulation (GCM) modeling, however, have shown that a decrease of only ~0.1% in solar activity over the 11-year sunspot cycle could produce a change in surface climate through the atmosphere's dynamic response to changes in stratospheric ozone and temperature"
Whereas you consider the thermohaline circulation "pretty speculative" (even 'though I provided papers referring directly to evidence for this for the periods specified), Bond et al certainly don't consider it to be speculative:The Arctic-Nordic Seas thus may have been a key region where solar-induced atmospheric changes were amplified and transmitted globally through their impact on sea ice and North Atlantic thermohaline overturning. Reduced northward heat transport, moreover, could have further altered North Atlantic latitudinal temperature and hydrologic gradients, potentially enhancing the climate response in low-latitude climates [e.g., (39)].
This assertion of yours is illogical: "Do you know of a minor change that would cause a 2C change in the Atlantic ocean. Certainly, it couldn't be solar which can only change irradiance by about 0.2C or so". Think about it. Your assertion requires that you know the magnitiude of the irradiance changes contemporaneous with the events. We've been talking about contributions from irradiance changes (0.2 oC's worth) during a period where there's a reliable reconstruction (Lean et al back to the Maunder Minimum). Do you know what the irradiance values were further back in the Holocene? I don't think so… -
Thumb at 04:26 AM on 21 July 2009Climate time lag
#130 - "Now that the oceans T appear to be flattening and cooling since early 2000s " How many cubic miles of land ice are running into the oceans as ice-cold water in recent years? Has this number been increasing? Wouldn't this have some effect on ocean temps in the same way adding ice to your drink will cool your drink? -
shawnhet at 04:17 AM on 21 July 2009Climate time lag
Chris:"That's not to say that there isn't also a lot of evidence over very long periods for N. hemisphere – S. hemisphere "see-saw" with compensating temperature rises and falls, or at least hemispherically-dominant phenomena. That's partly the theme of the Denton/Broecker paper in my post #116. For example the Dansgaard-Oeschger events that indicate large periodic temperature fluctuations in the Greenland cores are barely represented in Antarctic cores, and these are also interpreted in terms of exactly the same ocean/atmosphere heat transfer varaibility that likely underlie much of the MWP/LIA temperature variation. It's just that the D/O events entailed far more dramatic heat transfer changes possibly involving complete shutdown and later on rapid resumption of the thermohaline circulation in the N Atlantic." The thermohaline explanation is pretty speculative frankly, but IAC, the point is that the see-saw doesn't operate symmetrically on both sides of the equator. The Northern side fluctuates much more than the Southern side(and the Southern side doesn't really go up, when the Northern side goes down). ""I'm not going to comment on Bond events (other than in relation to D/O events for which Bond events might be a Holocene-scale minor continuation). I don't know enough about these and haven't got time to do much hunting in the scientific literature (last Thurs to Sat I was ill at home and found lots of time to do this – as well as watching the Open, the Ashes and the Tour de France!). If you know of any scientific literature that provides a good account of these phenomena as well as a discussion of potential causality I'd be more than happy to read these…" Bond events aren't minor. Do you know of a minor change that would cause a 2C change in the Atlantic ocean. Certainly, it couldn't be solar which can only change irradiance by about 0.2C or so. In that context, the correlation btw such changes and CRF makes no sense. IAC, good luck with your search. Let me know what you find out when you have explored other avenues of evidence. Here is a pretty good place to start IMO - Bond, G.C., B. Kromer, J. Beer, R. Muscheler, M.N. Evans, W. Showers, S. Hoffmann, R. Lotti- Bond, I. Hajdas and G. Bonani, Persistent solar influence on North Atlantic climate during the Holocene, Science 294, 2130–2136 (2001). Cheers, :) -
chris at 02:52 AM on 21 July 2009Climate time lag
re #131 shawnet, we've already seen that there is some uncertainty in the analysis of temperature changes during the time of the MWP/LIA, in solar irradiance reconstruction and so on. So whether the solar irradiance contribution is 0.14 oC or 0.2 oC is pretty immaterial; either of these is entirely consistent with the scientific evidence and it's hair-splitting to suggest that one or other (0.06 oC over hundreds of years!) is more correct. The point is that the currently best evidence for solar irradiance changes indicates that they are significant, and these, plus our understanding of likely greenhouse gas contributions to temperature change over this period, plus the evidence for ocean/atmosphere circulation contributions (see my post #123), allows a pretty self-consistent interpretation of (N. hemisphere) temperature variation over the period we've been discussing. Sadly, Kirkby gives a completely false picture of the science on this subject since he resolutely pretends that there has been no role for CO2 changes in paleotemperature variation, and completely misrepresents current science on solar contributions (let alone the other contributions we've discussed). There isn't any evidence for a CRF contribution during these periods whereas Kirkby insinuates that it's almost entirely CRF driven. That's not to say that there wasn't a small CRF, or other non-irradiance contribution…there just isn't any evidence for it, nor is there a requirement for it in order to understand the phenomena. I don't understand your point about "variance in Northern-Southern hemisphere temperature changes". The point I'm making based on the analysis of the Trouet paper in my post #123 (and quite a wealth of other work this subject, none of which is referred to by Kirkby who seems reluctant to give his readers a reliable account of research on this subject)….is that changes in N. hemisphere temperatures during the MWP/LIA periods likely have contributions from variations in heat trasfer from the equator to the high Northern latitudes. That doesn't imply that the S.H. had "….a larger climate response in any period, than the Northern one did." Far from it. In fact we expect that the climate response to be significantly less in the S.H. during changes in heat transfer to the high Northern latitudes for exactly the reason you suggest – there is a lot more ocean in the S.H. Again that's consistent with the evidence that the MWP/LIA were largely N. hemisphere phenomena and were likely fairly insignificant in terms of global scale warming/cooling. That's not to say that there isn't also a lot of evidence over very long periods for N. hemisphere – S. hemisphere "see-saw" with compensating temperature rises and falls, or at least hemispherically-dominant phenomena. That's partly the theme of the Denton/Broecker paper in my post #116. For example the Dansgaard-Oeschger events that indicate large periodic temperature fluctuations in the Greenland cores are barely represented in Antarctic cores, and these are also interpreted in terms of exactly the same ocean/atmosphere heat transfer varaibility that likely underlie much of the MWP/LIA temperature variation. It's just that the D/O events entailed far more dramatic heat transfer changes possibly involving complete shutdown and later on rapid resumption of the thermohaline circulation in the N Atlantic. Not sure what you mean by "current climate changes". If you truly mean "current" (i.e. contemporary) then these have essentially zero evidence for a casual CRF connection (we've discussed this at great length here!). Notice that the ITCZ changes are understandable in terms of the ocean/atmosphere heat transfer changes of the sort that Trouet et al provide additional strong evidence for (my post #123). As they suggest the trigger for these may be ocean surface heat changes arising from solar irradiance and volcanic forcing. It's unnecessary to attempt to sneak in spurious CRF contributions when these have been shown likely to be insignificant. Kirkby's own analysis indicates that these can't have made significant contributions to the MWP phenomenon, and they're certainly not required for the LIA as we've discussed. I'm not going to comment on Bond events (other than in relation to D/O events for which Bond events might be a Holocene-scale minor continuation). I don't know enough about these and haven't got time to do much hunting in the scientific literature (last Thurs to Sat I was ill at home and found lots of time to do this – as well as watching the Open, the Ashes and the Tour de France!). If you know of any scientific literature that provides a good account of these phenomena as well as a discussion of potential causality I'd be more than happy to read these….. -
shawnhet at 01:48 AM on 21 July 2009Climate time lag
Chris; "[FOUR] Note that the ~ 1 W/m^2 of Wang et al. (2005) is a general interpretation from two analyses using slightly different models that Wang et al made. One analysis gives a TSI cycle-averaged TSI change at the Maunder Minimum of 1.0 W/m^2; the other (containing a secular varying ephemeral region background) gives a change of 1.4 W/m^2. 1.4 W/m^2 gives almost exactly 0.2 oC temperature contribution to reduced surface temperature at the Maunder Minimum from irradiance variation using our parameters." So, IOW, if you take the highest value for TSI variation in the last few hundred years, you can account for the solar induced temperature change. However, if your reconstruction is on the high side, there will still be room for a solar amplification of some sort. Further, none of this really explains the close long term correlations btw precipitation and cosmic rays(as, for instance, with changes in the ITCZ and there relationship to Bond events). If cosmic rays had no effect on cloudiness, you would not expect this correlation to be present(and Bond events are much larger in magnitude than can be produced by TSI changes alone). As I keep saying, current climate changes are but one line of evidence for the CRF climate connection. "[FIVE] Again there are several uncertainties. We've already seen that the MWP and the LIA are predominantly defined in the N. hemisphere and we've used the paleoreconstruction having the largest variation (Moberg et al. (2005)). The atmospheric/ocean current changes that seem to be involved in MWP/LIA N hemisphere temperaturevariation (see my post just above) likely involve large changes in heat transfer to the high Northern latitudes, and the volcanic and solar influences on these might be amplified somewhat by albedo effects from slow Arctic sea ice regression/expansion over the long time scales involved. So the climate sensitivity might be a tad larger than the 0.8 W/m^2 over the very long timescales encompassing MWP/LIA temperature variation.." Just for the record, I don't buy these explanations for the variance in Northern-Southern hemisphere temp cahnges. I don't think anyone can find any evidence that the Southern Hemisphere has ever had a larger climate response in any period, than the Northern one did. There is a very simple reason for this IMO, the Northern hemisphere has more land than the Southern one, and land is more sensitive than water to changes in forcing. One only needs to look at maps of the ice extent in the N & S hemispheres during the last ice age to see what I mean. Cheers, :) -
thingadonta at 19:07 PM on 20 July 2009Climate time lag
The so called 'energy imbalance', ie the warming oceans over the last ~50 years, simply confirms the solar heat lag effect. (eg like air warming between 1 and 3 pm on any normal day). There is no 'energy imbalance' (eg like air warming between 1 and 3 pm on any normal day). Now that the oceans T appear to be flattening and cooling since early 2000s (ie like after 3pm on any normal day-already invalidating Hansen's prediction of "record-breaking T" in the 3 or 4 years after 2005- "the climate system is now being pushed so hard that I have suggested that we can say with confidence that 2005 will have a warmth comparable to that of 1998, and the remarkable 1998 global temperature record will soon be broken, if not this year than within the next several years.)," (http://junkscience.com/Greenhouse/imbalance_release.pdf) Another failed prediction of Hansen...thus, because the 'energy imbalance' is simple a heat lag efect from the sun, the air T will not rise much further,there is no 'imbalance', and oceans will probably cool further. This solar heat lag is really so simple, yet it is not investigated either here, or by Hansen. I he had of bothered to model solar heat lag into his imbalance he would have found it fitted nicely with the energy that has gone into the ocean from the solar peak in the 20th century, with heat lag. How the oceans are cooling, in line with the subsiding heat lag effect and subsiding sun. Too simple for 'global warmists by humans' to even bother investigating. -
Robbo the Yobbo at 15:22 PM on 20 July 2009Climate time lag
All the Spencer link form 1997 says is that a more complex vertical temperature structure is evident in the satellite data than is evident in the land based observations. Spencer still does this work for NASA. 'Analysis of the satellite record that began in 1979 indicates that global temperatures are increasing in the mid-troposphere, but the magnitude of the trend differs based on the analysis methods used in adjusting for factors such as orbital decay and inter-satellite differences. Mid-tropospheric and lower stratospheric temperature data are collected by NOAA's TIROS-N polar-orbiting satellites and adjusted for time-dependent biases by the Global Hydrology and Climate Center at the University of Alabama in Huntsville (UAH). An independent analysis is also performed by Remote Sensing Systems (RSS) and a third analysis has been preformed by Dr. Qiang Fu of the University of Washington (UW) (Fu et al. 2004)**. Not sure what the problem is? Let's see if I have got the Swanson paper right. There was a 1976/77 climate shift and one that occured in 2000/2001. Ignoring the end points as climate shifts - gives an underlying warming trend - between 1977 and 1997 of 0.1 degrees centigrade per decade. Not enough to be a serious concern. The current warming hiatus is likely to last 20 to 30 years. Yes I think that's everything. -
thingadonta at 13:05 PM on 20 July 2009Does ocean cooling disprove global warming?
The ocean T is flattening/cooling because there is no energy imbalance, and solar heat lag effects are now subsiding. Human c02 is having very little effect on surface or ocean T, with the sun and its heat lag on the oceans now waning. -
NewYorkJ at 09:18 AM on 20 July 2009Climate time lag
Re: #115 Robbo: "Spencer has done an ernormous amount in satellite sensing at temperature. He still works for NASA. " He even won an award for this work in the mid-90's. That was before a series of very large and embarassing errors were discovered, some by others, in the UAH data product. The errors have been numerous, of great magnitude on the global trend, and with corrections going almost all in the same upward direction. http://www.nsstc.uah.edu/data/msu/t2lt/readme.18Jul2009 Robbo: "Dr Roy Spencer has always been measured and rasonable." Hardly. When his data showed a per decade cooling trend, he uncritically accepted that it was entirely correct, all other data was wrong, and GCMs were mainly bunk - displaying the opposite characteristics of a good measured and reasonable skeptic. Article: Spencer and co-author Dr. William Braswell of Nichols Research Corporation have great confidence in the quality of their satellite data. "We've concluded there isn't a problem with the measurements," http://science.nasa.gov/newhome/headlines/essd5feb97_1.htm This is one reason why it's odd that he's still the go-to-reference for some. What's a bit more strange is I still see the 1997 NASA link above being cited by skeptics on occasion. -
chris at 03:03 AM on 20 July 2009Climate time lag
re #124 shawnet, Kirkby simply isn't a good guide for reliable understanding of these issue as we've seen already. I used the reconstruction of Judith Lean: Y.-M. Wang, J. L. Lean and N. R. Sheeley, Jr. Modeling the Sun's Magnetic Field and Irradiance since 1713 Astrophysical J. 625 522-538 Lean, J. L., and D. H. Rind (2008), How natural and anthropogenic influences alter global and regional surface temperatures: 1889 to 2006, Geophys. Res. Lett., 35, L18701 Here's the sentence on page 6 of Kirkby which you have used to make your calculation: "The increase in irradiance amounts to less than 0.5 W/m^2, which corresponds to about 0.08 W/m^2 at the top of the atmosphere, globally averaged (Fig. 5). Assuming a climate sensitivity of 0.7 K/W/m^2, this would contribute less than 0.06C of the estimated 0.6 C mean global warming between the Maunder Minimum and the middle of last century, before significant anthropogenic contributions could be involved." Those two sentences are packed with inaccuracies: [ONE] the data in his "Fig 5" shows two reconstructions of Lean (1995 and 2002). However the reference to the Lean 2002 data refers to a paper (his ref 6) in which Lean only analyzes the solar irradiance back to 1840. [TWO] the data in his Figure 5 assigned to Lean 2002, looks more like a solar irradiance reconstruction that Lean published a few years later in 2005 in which she and her collaborators explicitly considered irradiance changes since the Maunder Minimum (it's the one I used): Y.-M. Wang, J. L. Lean and N. R. Sheeley, Jr. Modeling the Sun's Magnetic Field and Irradiance since 1713 Astrophysical J. 625 522-538 Lean's analysis gives a cycle-average reduction in the total solar irradiance at the time of the Maunder Minimum of ~ 1 W/m^2 (rather than Kirkby's "…less than 0.5 W/m^2). 1 W/m^2 gives a temperature change of 1 * 0.25 (geometry)* 0.7 (albedo)* 0.8 (sensitivity) or 0.14 oC. (see point [FOUR] for a bit more on this analysis). [THREE] We've already seen that Kirkby's statement about "…. the middle of last century, before significant anthropogenic contributions could be involved." is entirely bogus. The anthropogenic contribution to surface temperature results from a pre-"middle of last century" change in atmospheric CO2 from 280 ppm (pre-industrial) to 310 ppm (in 1940). This gives near 0.44 oC of warming at equilibrium within a climate sensitivity of 3 oC. [FOUR] Note that the ~ 1 W/m^2 of Wang et al. (2005) is a general interpretation from two analyses using slightly different models that Wang et al made. One analysis gives a TSI cycle-averaged TSI change at the Maunder Minimum of 1.0 W/m^2; the other (containing a secular varying ephemeral region background) gives a change of 1.4 W/m^2. 1.4 W/m^2 gives almost exactly 0.2 oC temperature contribution to reduced surface temperature at the Maunder Minimum from irradiance variation using our parameters.. [FIVE] Again there are several uncertainties. We've already seen that the MWP and the LIA are predominantly defined in the N. hemisphere and we've used the paleoreconstruction having the largest variation (Moberg et al. (2005)). The atmospheric/ocean current changes that seem to be involved in MWP/LIA N hemisphere temperaturevariation (see my post just above) likely involve large changes in heat transfer to the high Northern latitudes, and the volcanic and solar influences on these might be amplified somewhat by albedo effects from slow Arctic sea ice regression/expansion over the long time scales involved. So the climate sensitivity might be a tad larger than the 0.8 W/m^2 over the very long timescales encompassing MWP/LIA temperature variation.. -
thingadonta at 21:12 PM on 19 July 2009Climate time lag
response to response to 106: "The energy imbalance has been directly observed, independent of models, theories or predictions" This is patently false, and you know it. The 'energy imbalance' has been derived and modelled from all the usual suspects, ie -greenhouse gases, aerosols, and such like. Reference: climate-science.org/PDF/Earth.EnergyImbalance.pdf. You have lost credibility. The energy imbalance of Hansen 2005 is modelled, it is not an "observation", and is certainly not "independant of models, theories and predictions". The model, (even Hansen and co use the word) assumes strong c02 forcing, to arrive at the figure. Solar heat lags are not mentioned or investigated. With a solar heat lag the ocean would indeed warm, but the derived imbalance is actually based on assumed c02 forcing, and then 'checked' by model runs, also assuming c02 forcing. Oceans warming is probably correct, the imbalance estimate is a model. So much for your argument, and ability to properly investigate assumptions, the above is just a re-iteration of the creed of c02, nothing more. -
shawnhet at 03:59 AM on 19 July 2009Climate time lag
Oops, I misread the last bit of your post. Please ignore the last paragraph of my previous post. SOrry. -
shawnhet at 03:57 AM on 19 July 2009Climate time lag
Chris, perhaps I have misunderstood you somewhere, so a point of clarification here. You say that 0.2C was caused by solar changes, so working backwards, this implies approximately 1.5W/m2 increase in TSI by my back of the envelope calculation(1.5W/m2 translates into about a 0.24W/m2 forcing at the top of the atmosphere(globally averaged), which in turn translates into ~.17 deg C. at 0.7Wm2/deg C. I confess I didn't look too closely at every reference you provided, so I may have missed the TSI reconstruction you are using. My understanding is that long-term TSI variations(no matter which one) are currently expected to be much less than that. The source for my conclusions is based on Kirkby's position that TSI varies (in recent times) by about 0.5W/m2. There is clearly a contradiction btw *that number* and the claim that solar influences led to a 0.2C temperature difference. If the 0.5W/m2 number is accurate, then a long-term correlation btw solar and climate influences needs some sort of amplification. BTW, the point about ascribing climate changes to changes in the ocean was that it is begging the question. Clearly, ocean temperature fluctuations have a major impact on the climate, but what causes the ocean's behavior to change? There is no contradiction btw saying that NAO was consistently positive in the MWP and saying that MWP was warmer because of a solar influence. Cheers, :) -
chris at 23:50 PM on 18 July 2009Climate time lag
a bit of a formatting error in my post just above - hope this works better!Chris, you've just spent the last few posts arguing that solar contributions to climate change are negligible. For the LIA, the increase is due to CO2 from land use changes(ignoring the fact that those same land use changes also cool the climate) and for MWP the cause is the TH circulation......
Please don't misrepresent straightforward posts shawnet. What are you hoping to achieve by distortion? Nowhere did I say that solar contributions to climate change are negligible. I have already stated that one cannot understand the paleotemperature/greenhouse relationships over the long earth history without taking into account the steady long term increase in solar output during earth history. I've pointed out the research of solar scientists that the evidence supports a solar contribution of around 0.1 oC to 20th century warming and that the solar contribution to the around 0.6 oC of warming from the Maunder minimum to the mid 20th century was likely around 0.2 oC. As far as the evidence goes, the reduction in N. hemisphere temperature from the baseline -0.35/-0.4 equilibrium temperature to a value near -0.6 oC was likely largely a solar effect as was its recovery back to the equilibrium level near -0.35/-0.4 oC. I didn't say that "For the LIA, the increase is due to CO2 from land use changes" did I shawnet. I pointed out that the well characterised anthropogenic rise in atmospheric from the start of the 19th century to the mid 20th century, the early sources of which were from land use changes, is expected to give a temperature rise approaching 0.5 oC at equilibrium, perhaps giving around 0.35 oC by 1950 with the rest "in the pipeline" to be realized post-1950. I pointed out the likely solar contribution (see previous paragraph) and a volcanic contribution, and cited some empirical evidence for a ocean/atmospnhere heat transfer (Gulf stream) reduction which may have contributed to high N hemisphere cooling during the LIA. I even said in relation to the MWP/LIA: "We don't have to consider a role for CO2 (there was a little contribution but not much) other than the very well-characterised and quite large contribution to the long term temperature rise from around 1800 to the mid 20th century base period." And yet you paraphrase my comments on this subject to infer that I stated that "For the LIA, the increase is due to CO2 from land use changes…Go figure! You did ask a relevant question about about the possible contributions of changes in ocean circulation that could have given rise to the around 0.2-0.25 oC rise in high N. hemisphere temperature and the 0.2-0.25 oC drop in high N. hemisphere during the LIA, according to the Moberg reconstruction. This has been addressed in a recent detailed analysis of ocean and atmospheric circulation in the North Atlantic during the MWP and the LIA: Valérie Trouet et al. (2009) Persistent Positive North Atlantic Oscillation Mode Dominated the Medieval Climate Anomaly Science 324, 787-80 http://www.sciencemag.org/cgi/content/abstract/324/5923/78 (abstract below) What might be the origin of these circulation changes? The authors conclude:"The persistent positive phase reconstructed for the MCA appears to be associated with prevailing La Niña–like conditions possibly initiated by enhanced solar irradiance and/or reduced volcanic activity (21) (Fig. 4D) and amplified and prolonged by enhanced AMOC."
(AMOC being "Atlantic meridional overturning circulation") Solar irradiance and volcanic activity. Again no need to postulate a role for the unsubstantiated CRF hypothesis ------------------------------------------------------- abstract: The Medieval Climate Anomaly (MCA) was the most recent pre-industrial era warm interval of European climate, yet its driving mechanisms remain uncertain. We present here a 947-year-long multidecadal North Atlantic Oscillation (NAO) reconstruction and find a persistent positive NAO during the MCA. Supplementary reconstructions based on climate model results and proxy data indicate a clear shift to weaker NAO conditions into the Little Ice Age (LIA). Globally distributed proxy data suggest that this NAO shift is one aspect of a global MCA-LIA climate transition that probably was coupled to prevailing La Niña–like conditions amplified by an intensified Atlantic meridional overturning circulation during the MCA. -
chris at 23:42 PM on 18 July 2009Climate time lag
Chris, you've just spent the last few posts arguing that solar contributions to climate change are negligible. For the LIA, the increase is due to CO2 from land use changes(ignoring the fact that those same land use changes also cool the climate) and for MWP the cause is the TH circulation......
Please don't misrepresent straightforward posts shawnet. What are you hoping to achieve by distortion? Nowhere did I say that solar contributions to climate change are negligible. I have already stated that one cannot understand the paleotemperature/greenhouse relationships over the long earth history without taking into account the steady long term increase in solar output during earth history. I've pointed out the research of solar scientists that the evidence supports a solar contribution of around 0.1 oC to 20th century warming and that the solar contribution to the around 0.6 oC of warming from the Maunder minimum to the mid 20th century was likely around 0.2 oC. As far as the evidence goes, the reduction in N. hemisphere temperature from the baseline -0.35/-0.4 equilibrium temperature to a value near -0.6 oC was likely largely a solar effect as was its recovery back to the equilibrium level near -0.35/-0.4 oC. I didn't say that "For the LIA, the increase is due to CO2 from land use changes" did I shawnet. I pointed out that the well characterised anthropogenic rise in atmospheric from the start of the 19th century to the mid 20th century, the early sources of which were from land use changes, is expected to give a temperature rise approaching 0.5 oC at equilibrium, perhaps giving around 0.35 oC by 1950 with the rest "in the pipeline" to be realized post-1950. I pointed out the likely solar contribution (see previous paragraph) and a volcanic contribution, and cited some empirical evidence for a ocean/atmospnhere heat transfer (Gulf stream) reduction which may have contributed to high N hemisphere cooling during the LIA. I even said in relation to the MWP/LIA "We don't have to consider a role for CO2 (there was a little contribution but not much) other than the very well-characterised and quite large contribution to the long term temperature rise from around 1800 to the mid 20th century base period." And yet you paraphrase my comments on this subject to infer that I stated that "For the LIA, the increase is due to CO2 from land use changes…Go figure! You did ask a relevant question about about the possible contributions of changes in ocean circulation that could have given rise to the around 0.2-0.25 oC rise in high N. hemisphere temperature and the 0.2-0.25 oC drop in high N. hemisphere during the LIA, according to the Moberg reconstruction. This has been addressed in a recent detailed analysis of ocean and atmospheric circulation in the North Atlantic during the MWP and the LIA: Valérie Trouet et al. (2009) Persistent Positive North Atlantic Oscillation Mode Dominated the Medieval Climate Anomaly Science 324, 787-80 http://www.sciencemag.org/cgi/content/abstract/324/5923/78 (abstract below) What might be the origin of these circulation changes? The authors conclude:"The persistent positive phase reconstructed for the MCA appears to be associated with prevailing La Niña–like conditions possibly initiated by enhanced solar irradiance and/or reduced volcanic activity (21) (Fig. 4D) and amplified and prolonged by enhanced AMOC."
(AMOC being "Atlantic meridional overturning circulation") Solar irradiance and volcanic activity. Again no need to postulate a role for the unsubstantiated CRF hypothesis ------------------------------------------------------- abstract: The Medieval Climate Anomaly (MCA) was the most recent pre-industrial era warm interval of European climate, yet its driving mechanisms remain uncertain. We present here a 947-year-long multidecadal North Atlantic Oscillation (NAO) reconstruction and find a persistent positive NAO during the MCA. Supplementary reconstructions based on climate model results and proxy data indicate a clear shift to weaker NAO conditions into the Little Ice Age (LIA). Globally distributed proxy data suggest that this NAO shift is one aspect of a global MCA-LIA climate transition that probably was coupled to prevailing La Niña–like conditions amplified by an intensified Atlantic meridional overturning circulation during the MCA. -
thingadonta at 21:27 PM on 18 July 2009Climate time lag
Sorry for the capital letters in the last post, I just wanted to differentiate my words from others. I wont do it anymore. -
thingadonta at 20:31 PM on 18 July 2009Climate time lag
re: response to 107: I did read the whole Hansen 2005 paper, and Wong 2005,and I'm not at all convinced that so-called energy imbalances are 'measured' and not modelled-in fact I think Hansen 2005 is actually saying that he does 'model' the imbalance, both current and predicted. Hansen 2005 states that he derives 'predicted' energy imbalance from greenhouse gas models. "First, the predicted energy imbalance DUE TO INCREASING GREENHOUSE GASES has grown to 0.85 ± 0.15 W/m2". (Hansen 2005) (although he also conveniently often fuses the 2-'calculated' and 'predicted'). However, you state the energy imbalance of the climate is "measured" independant of theories, models and predictions: "The energy imbalance has been directly observed, independent of models, theories or predictions". (THIS IS WRONG, IT IS "CALCULATED", USING A MODELLED RELATIONSHIP BETWEEN OCEAN HEAT, ATMOSPHERE T, AND OUTGOING AND INCOMING SOLAR ENERGY.MOREOVOER, this modelling of Hansen 2005 does not take into account solar changes and heat lags in 20th century, it is solely MODELLED using strong c02 forcings of the 20th century. Contrary to what you state, there is NO way this relationship between ocean heat, climate T, and incoming-outgoing heat can be 'measured', outside of modelling, and assumptions. Moreover, the predictions or Hansen 2005 of future energy imbalances are based on greenhouse gas models, further IMPOSED on this exisitn modelling. It is an exquisite case of modelling on modelling on modelling. THERE IS NO INVESTIGATION, OR INPUT FROM SOLAR EFECTS IN THE 20TH CENTURY IN THE HANSEN 2005 PAPER-NOT EVEN MENTIONED. Your points: 1."We predict there will be an energy imbalance due to increasing CO2". (THIS IS A MODEL, AS YOU SAY, BASED ON MODELLED GREENHOUSE -T RELATIONSHIPS IN THE 20TH CENTURY-WITHOUT TAKING INTO AFFECT THE SUN-AS ALSO DOES HANSEN 2005) 2."Empirical observations of increasing ocean heat confirm there is an energy imbalance". (THIS 'IMBALANCE' IS DERIVED FROM GREENHOUSE GAS MODELS IN THE 20TH CENTURY-THERE IS NO "CONFIRMATION" UNLESS ONE FIRST ASSUMES THAT THE SUN HAS HAD LITTLE/NO EFFECT, WITH NO SOLAR HEAT LAGS-WHICH CNACEL THE IMBALANCE) 3."The energy imbalance, calculated from ocean heat measurements, is steadily growing and is currently at 0.85 W/m2" (A MEANINGLESS FIGURE BASED ON MODELS BETWEEN CLIMATE'S CURRENT T AND OCEAN HEAT-AS DERIVED FROM MODELLED PAST RELATIONSHIPS OF SUN-OCEAN RELATIONSHIPS-WONG 2005) "In terms of the sun/heat lag issue, all we need to know is direct observations tell us the planet's energy imbalance has been gradually increasing over the past 40 years". (NO, OCEANS HAVE BEEN HEATING IN LINE WITH SOLAR ACTIVITY AND HEAT LAG-THIS IS NOT INVESTIGATED IN HANSEN 2005 PAPER, IT IS ONLY ASSUMED TO BE DUE TO C02). "Therefore, recent global warming cannot be a case of lagged solar warming which would show the energy imbalance approaching equilibrium (in fact, should've reached equilibrium approximately 20 years ago)". IT IS ONLY ASSUMED TO BE NOT BE APPROACHING EQUILIBRIUM IF ONE FIRST ASSUMES T IS BEING DRIVEN BY C02 EFFECTS, WHICH THEN PRODUCES THE "IMBALANCE", THEN IS NO INVESTIGATION MADE OF SOALR ACTIVITY, SOLAR LAGS, AND EFFECTS ON THIS ON OCEAN HEAT IN 20TH CENTURY. Heat solar lag effects would produce increasing ocean heat content, which would level off, as it has done since the early 2000s in the ocean-land T. There is no 'imbalance', unless one models the ocean-atmosphere-solar system as being driven by c02 - the paper by Hansen 2005 does NOT address solar heat lag, solar effects, it only assumes that there is a long climate heat lag from c02 (not the sun), and then assumes an imbalance from this effect, then predicts a long term lag from this current, modelled imbalance, ALL BASED ON GREENHOUSE GAS MODELLING. Circular, and willfully ignorant. Hansen 2005 paper does not refute solar heat lag, because Hansen himself does not address it in the paper. He states that he uses greenhosue gas modelling. "First, the predicted energy imbalance DUE TO INCREASING GREENHOUSE GASES has grown to 0.85 ± 0.15 W/m2". In other words he assumes that past century T rise is by greenhouse gases first, which has therefore created a "predicted energy imbalance", by "increasing greenhouse gases". If we assume an energy imbalanace, then we get an energy imbalance. Mindbloggingly circular and stupid. There is no evidence to conclude, as he does, that the there is an energy imbalance at present, unless one assumes that T is rising by C02 in the first place, as he states above, that he does. This is not proof, is is circular reasoning. If we assume an energy imbalanace, then we get an energy imbalance. He uses the same argument further down to get a figure of 0.6 degrees C still 'in the pipeline' ie from ocean heat content, ie imbalanced with c02 forcing. NOWHERE does he discuss or address or acknowldedge the fundamental assumptions of the models he bases this figure on, ie that he ASSUMES T rise is being driven by c02, and not the sun. I am not convinved that, both the paper of WONG 2005 and Hansen 2005- that they don't model an "imbalance" based on greenhouse gas modelling, and also neither address solar effects and heat lags. Climate is approaching equilibrium, T has levelled off since the early 2000s, in both land and ocean, and this so-called large climate 'imbalance' is only in the heads of the human-induced global warmists, getting bigger every day as they attempt to explain why the earth is no longer heating sicne the early 2000s.There may be some ocean heat lag leftfrom solar actvity in 20h century, particularly in the southern hemisphere, but c02 is playing very little effect, as can be seen over the last decade as T from the sun levels off-co2 has been trying to heat the earth sicne this time, but it is just way too small to have any effect. There is no large current energy imbalance, this is a conclusion based on assumed strong c02 forcing, conceptually 'stealing' the real climate heat lag discovered from the sun, and which 'model' does not even bother investigating solar activity and solar heat lags (Hansen 2005 Wong 2005).
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