sunny starry skies

I'm quite happy to have as evidence the jetsteam moving south giving NW Europe colder winters - the last couple of winters support that hypothesis nicely (not enough of a sample to prove the case of course as VP says). But the crucial point I think Iceberg was making is that he fails to see how that would make the N Hemisphere as a whole cool down. Yes, NW Europe and parts of the USA have been cold this winter, but the Northern Hemisphere as a whole has been unusually (record-breakingly) warm. Hence there is no evidence there to support a southward shift in the jetstream producing a cooler hemisphere. The evidence to me suggests that whatever perturbation, PDO, solar forcing, whatever, that has moved the jetstream south, has forced a redistribution of temperatures within the hemisphere, but not a cooling of the whole hemisphere. BFTP, there's no evidence for a slowing in the warming trend. Tamino's riddle-me-this post which I have linked to too many times shows this beyond reasonable doubt. Any trend in the temperature data shorter than 15 years was shown statistically to be within the noise, rather than the trend itself. And recent month plots solidly on average or above average in relation to that rising trend of the last 30+ years. http://tamino.wordpress.com/2009/12/07/riddle-me-this/ http://tamino.wordpress.com/2009/12/15/how-long/ And more interesting work from Tamino, which it seems he's planning to publish too - Watts' claim that station dropout or adjustments in the GISS dataset introdices biases, already shown to be incorrect by others, has been proven to be totally wrong. I wonder if we'll see a retraction from Watts?? http://tamino.wordpress.com/2010/02/25/false-claims-proven-false/ This has been replicated, in true scientific style: http://clearclimatecode.org/the-1990s-station-dropout-does-not-have-a-warming-effect/ http://rankexploits.com/musings/2010/a-simple-model-for-spatially-weighted-temp-analysis/ sss

Palaeo-reconstructions of the Sun appear to be a bone of some contention in the scientific literature so far as I can see. The last 1000 years is quite well constrained, and radiocarbon/beryllium-10 reconstructions are in reasonable (though not perfect, as C-Bob's graph shows) agreement with the sunspots. It's beyond this that things get more tricky. Solanki et al (2004) proposed that he could reconstruct solar activity back 11,000 years, and found the Sun's recent activity remarkably high through that time period. http://www.nature.com/nature/journal/v431/n7012/abs/nature02995.html But they conclude in their abstract: "Although the rarity of the current episode of high average sunspot numbers may indicate that the Sun has contributed to the unusual climate change during the twentieth century, we point out that solar variability is unlikely to have been the dominant cause of the strong warming during the past three decades" However, a brief search provides this article by Ogurtsov (2007) which casts some doubt on Solanki's claim, suggesting that you cannot successfully reconstruct solar activity all that far back using those palaeoclimatic records. http://www.springerlink.com/content/mg547654r7523746/ This link (Muscheler et al, 2005), which should hopefully work for everyone, discusses solar activity and climate as a response to Solanki et al: http://www.cgd.ucar.edu/ccr/raimund/publications/Muscheler_et_al_Nature2005.pdf "The comparison between the physical quantities, the 14C-production rate and the solarmodulation parameter, and the visually based sunspot record reveals similarities and striking differences (Fig. 2). The 11-year solar cycle is distinct in all records. On the other hand, solar magnetic modulation was higher or comparable to today during the late eighteenth (and twelfth) century and around AD 1600, whereas sunspot numbers were highest over the recent decades. Sunspot numbers fell to zero during the Maunder Minimum (AD 1650–1700), whereas 14C production and solar modulation continued to vary." This highlights the nonlinear connection between SN and solar activity directly influencing Earth. Muscheler's take on the 'unusually high solar activity' question at RealClimate is here: http://www.realclimate.org/index.php/archives/2005/08/did-the-sun-hit-record-highs-over-the-last-few-decades/ But, this is threatening to be a longer-than-planned post, as it's an interesting topic! To go back to TWS' question about reliable proxies, I think the answer is a frustratingly vague, yes there are proxies, but not entirely, as the proxies don't vary exactly with sunspot number. But of course, as the proxies are recording changes in energy transfer from the Sun (as opposed to changes on the surface of the Sun), they may be even better than sunspot number for measuring energy received at Earth! But as they don't all agree, it's hard to tell which one to use! But as far as how this affects the temperature indices - both Solanki and Muscheler say that solar activity variations can have only a small impact on recent climate change, so would put them in the brackets of the small variations discussed above. My take on the rate of heating/cooling discussion is that, in my opinion, you have to consider the heating of 1C to be 1K out of 287K heat of the Earth's surface, and therefore it is a very small proportion. Hence the rate of heating or cooling will not change significantly whether the surface temperature is 287K or 286K, so I'm not sure that C-Bob's argument will work. Certainly I don't think the effect would be dramatic in that I think the effect of cooling from 286K (13C) to 285.7K (Maunder Min) would be pretty much the same as cooling from 287K to 286.7K (14C to 13.7C). Unless anyone can say why the effect would be substantially nonlinear? sss

I think B9b just lost it's no-claims bonus.... Well said VP - science is a hard, abrasive place, but the way to succeed with your argument is to use sound logic and come up with evidence. I don't always agree with VP, but at least he's clear and logical about what he says and why. GWO (Dilley) have provided none of this, and shown no knowledge of palaeoclimate. I'm not surprised he's not managed to get it published in anywhere scientific, if his book contains the level of understanding shown here and elsewhere, as I've posted. Here's the latest example of poor science from Dilley: "Numerical data fitting climate cycle curves...my, sure sounds and looks like proof [1]. AGW people cannot fit CO2 data to show CO2 is the cause of warming [2]. Actually it is the reverse, temperatures rise first and then CO2 through natural processes [3]. It is well documented that Milankovich Cycles have a great influence on climate cycles [4]. The lunar cycles are a part of these cycles, so are you ignoring known science?[5]" 1: As VP said, curve fitting does not equal causality. I've seen someone connect global temperature with US presidents... 2: Actually they can, but clearly you have not read the relevant parts of AR4. Oddly enough, it's not a simple linear regression excersie. 3: One of the oldest, and longest-refuted, skeptic claims. If you still hold to this you are truly deluded. Orbitally-forced temperature drove the release of CO2 by warming oceans up until recently, since the industrial period we've released CO2 all by ourselves. CO2, the greenhouse gas, does the rest. Regardless of the particular science here, do you not believe that there is more than one way to skin a cat (or drive a temperature change, or a CO2 release)? 4: The only bit you have right so far. 5: Milankovitch cycles (tilt, precession and eccentricity) do not include the Moon, with the one exception that precession is partially caused by the Moon. So VP was not ignoring the 'known science'. So in the space of three lines, you managed to get four things fundamentally wrong. I suppose you deserve a credit for that. Otherwise it's an 'F' from me. I'm not in the business of handing out 'abuse' as some would call it, but I will call you out when you make incorrect or unsubstantiated assertions. Back to something sensible... While the East Antarctic Ice Sheet is very stable, the serious issue is on the West Antarctic Ice Sheet, which is grounded below sea level, and has steadily retreating grounding lines. High air temperatures may not be required to melt it, as warm ocean water can do the job very effectively from beneath. Additionally, there are observations of accelerations of glaciers draining the WAIS and Greenland. The crucial point is that during the last interglacial, when air temperatures were ~2C higher than at present, sea level was ~6m higher. Where did all that water come from? A reasonable guess is the WAIS, Greenland or both. sss

Solar activity - there's a fundamental difference between attributing the magnitude of changes by looking at observational data in the past and forecasting what those future changes will be. We have a good handle on climate forcings, including solar, by looking at past data, and by understanding the mechanisms by which these forcings work (solar, GHG, volcanic, ENSO). From past data, we can say that solar changes have a ~0.1C effect on the short term, and up to 0.3-0.5C in deep minima, such as Maunder. Now prediction of future solar activity is, as I think we'll agree, an uncertain business. but that does not mean we have no idea about the magnitude of likely future forcing. You can hypothesise about some fantasy super-Maunder minimum, but it has no basis in science as there is no data suggesting this has happened in the recent palaeoclimatic record (which is I think what G-W was driving at?), and notably in radiocarbon production records of solar activity. What this means is that Maunder Min provides a very reasonable low point for solar activity. A very reasonable high point for solar activity is in the last 50 years which, as some have pointed out, is pretty high on the scale for the whole Holocene. Any future forecast will be in between those ranges. If we drop quickly into a full-on Maunder Minimum, then the reduction in forcing will be equivalent to about a 0.3C drop. Maintaining our high activity values will result in no change to our current forcing. So the difference is between what you and I consider to be "solar uncertainty." I consider it to be a range of ~0.3C with recent decades' forcing at the top of that scale. We do not know exactly what the future behaviour will be, but we do have a good idea of the range within which the behaviour will lie. An assertion of a larger range does not appear supported by the facts. You have yet again not provided anything to support your assertions. Can I have a pair of your anti-AGW assumptive-tinted glasses please? The reason it is less important than AGW is obvious - the temperature changes that will be the consequence of GHGs are an order of magnitude larger than the forcing we have seen from the Sun. And are our fault. So no, you did not have it straight. What's a 'negative solar feedback'? Seeing as solar activity would be a driver of any changes, it cannot be a feedback? I think you misunderstand the meaning of the word "feedback". sss

I would encourage anyone who may be swayed by the predictions of GWO to read that link. You'll find that David utterly fails to provide any information as to the source of his temperature graphs, or his secret 'PFM', therefore preventing anybody from reproducing his work scientifically. Tamino picks him up on the fact that his two temperature records don't even agree with each other, yet no response. Hell, he uses a temperature record he goes on to say he's proven false with his method, which sounds dangerously like circular (quite apart from foolish) reasoning to me. To quote Tamino: "He [Dilley] not only made remarkable claims, he contradicts the vast majority of the climate science community. So: I asked him where he got his data. Seems like a pretty simple request to me. After all, if you're going to make remarkable claims about global warming you should have some actual data, right? So far the only answers forthcoming are "world climate report" (a blog with no data) and "Data from present to the year 1000 came from one source and data from present to 5k years ago from another source." WHAT source? Mr. Dilley, do you even have any actual data, or did you just copy somebody else's graphs? Whose graphs? What data?" I couldn't have said it better myself. He has a 5000year data source that he will not reveal that does not agree with all the published Holocene work. No coherent response from Dilley, except for some blethering about global conspiracies of scientists (truly laughable, given the rewards for good new science), and various further demonstrations of an utter failure to grasp palaeoclimatology. But the finest comment had to wait till last... David Dilley, of GWO said this [May 7th 2007 at 8:13am]: "But, it is accurate to say that man was not involved in the other 29 episodes, and thus CO2 can be discounted as the global warming agent." How wrong can one person possibly be? The basic fallacy here is so obvious I need not even point it out. And that is yet another reason why I see no reason to waste my time reading his book. sss

I stated that "From the evidence on here, you're struggling with the difference between weather and climate, let alone palaeoclimate, and so no I am not going to read your book." I am entirely entitled to that opinion, based on the evidence I see presented here, which is evidence of someone who has a very incomplete knowledge of really basic palaeoclimate, weather and climate. Anyone can write a book, but not all books are worth reading. I'd rather base my understanding on somebody demonstrating a knowledge of the basics. I know that NSSC thinks me dismissive of all alternative possibilities for the observed global warming or sea level rise (a good indicator of warming, being due to both increased heat content and to melting of terrestrially-based ice), but I am open to alternative hypotheses, provided they are supported by sound evidence. I get annoyed at those linking cold regional weather to some proposed change to colder global climate, when this is blatantly false. The statement suggesting sea level rise cannot happen in the next 50 or 100 years is also false - just look at the observational data and you will see that this is blatantly incorrent: Recent sea level is on a steady rapid rise, with only very minor fluctuations: http://www.cmar.csir...st_last_15.html Sea level over the last 150 years has been steadily rising, with a distinct accelerating trend (bottom figure): http://www.cmar.csir...ew_hundred.html This sea level rise and accelerating trend is in direct contrast to pre-industrial sea level, which had stabilised, following a decelerating trend through the Holocene. Recent (being last 150 years) sea level rise is a dramatic departure from the long-term behaviour (last 3000 years, bottom graph): http://www.cmar.csir...hist_intro.html Where's your sudden halting of sea level rise going to come from? Why is sea level rising, and the rate of rise accelerating, in a manner quite unexpected, from a system that had stabilised in the pre-industrial period? sss

It's been cold here too - the Met Office have said that this is Scotland's coldest winter since 1963 and I believe that. But, exactly as Jethro posted - regional-scale cold/warm is weather. You do realise that this is one of the warmest winters (if not the warmest) globally on record. Other regions of the world, notably Greenland and Arctic Canada, where the cold air ought to be, are remarkably warm. This was (and others may correct me if I'm wrong) an unusual west-based El Nino, that would not be expected to interact with weather patterns in a 'normal' way. The western US and Canada was clearly remarkably warm too. From the evidence on here, you're struggling with the difference between weather and climate, let alone palaeoclimate, and so no I'm not going to read your book. sss

Oh dear. Did you write that with a straight face? Not really worth responding to, as you clearly are more interested in politics than hard science, and have little idea about the science of palaeoclimatology. Dare I ask for some evidence for these bizarre ideas? Your phantom cooling cycle and falling sea levels are yet to be observed. I particularly like the "because global cooling began in 2008." Clearly you were on holiday for the last four record or near-record warm months globally. Have you even looked at temperature records? The current view is that sea level rise was underestimated in AR4. Vermeer and Rahmstorf 2009: http://www.pnas.org/content/early/2009/12/04/0907765106.full.pdf "We propose a simple relationship linking global sea-level variations on time scales of decades to centuries to global mean temperature. This relationship is tested on synthetic data from a global climate model for the past millennium and the next century. When applied to observed data of sea level and temperature for 1880–2000, and taking into account known anthropogenic hydrologic contributions to sea level, the correlation is >0.99, explaining 98% of the variance. For future global temperature scenarios of the Intergovernmental Panel on Climate Change’s Fourth Assessment Report, the relationship projects a sea-level rise ranging from 75 to 190 cm for the period 1990–2100." sss

We've been here before. How do you get Quaternary glacial cycles without the positive feedbacks identified in the climate system, given that the orbital forcing trigger is small, and CO2 alone cannot amplify the signal to the required magnitude? Why do you get a 'sawtooth' in the general pattern of glacial cycles? The physical feedback mechanisms are straightforward: higher temperature = more water vapour in the atmosphere, reduced albedo = less incoming radiation reflected to space. These are not hypothesised, they are demonstrable physical processes. On forecasting - What has been the accuracy of the Met Office's annual global temperature forecast over the last 10 years, and why is it so good? Luck? Are you seriously trying to connect uncertainties in AGW theory and forecasting of solar activity?? Time for me to do some head-banging because they are two different sciences altogether. We have a decent handle on the forcing factors of Earth's climate, whether you like it or not, and as shown many times over in attribution studies, and in year-to-year forecasting of global temperature. We do not have anything like the same handle on forecasting the activity of the Sun, and so revisions in forecasts are entirely expected, and not to be sneered at. FYI, Landscheidt does not appear to be correct either, as he forecast <50 sunspot number peak, which does not look to be happening. Reduced activity, yes, but no Maunder Minimum just yet. Reduced solar activity will at most plausibly be Maunder Minimum in scale, as there is no palaeoclimatic evidence for more dramatic cold episodes in the Holocene, hence Iceberg's discussion of a ~0.3C global temperature drop. That pales into insignificance when compared to a ~2C to ~4C rise forced by GHGs. "bigger negative solar feedbacks tha[n] the likes of Landscheidt has proposed"?? Too much to hope for, but.... any evidence????? sss

CB, you'll hurt your head if you keep doing that! Iceberg's right, though. You can point to "up to 1C dips", but the mean is rather less dramatic than that.... in fact right in line with our understanding of a ~0.1C modern-day variation, and a ~0.3C dip in LIA. Sorry it's not in line with what you think to be right, but unless you have evidence to say otherwise, I have to agree with Iceberg. Iceberg does outline an internally-consistent and straightforward suggestion for the cause of the Maunder Minimum, and why it wouldn't have that much effect in the face of GHG forcing. http://science.nasa.gov/headlines/y2009/29may_noaaprediction.htm Lots of uncertainty in future predictions, plenty of revisions and competing hypotheses, but no forecast imminent Maunder Minimum, or sunspot number below 50 as per Landscheidt's predictions. sss

There's a pretty obvious difference between monitoring activity and modelling future projections. Why has NASA's monitoring been dodgy? Since when has forecasting solar activity been an exact science? It's still uncertain as to how strong cycle 24 will be, let alone 25, which is well out in the region of conjecture. So I really love your "belatedly growing admission" comment, where you try and suggest that solar physicists would be, erm... hiding the decline.... I think you'll find that the challenge of forecasting future solar activity has always been a difficult challenge, and so the signs over the last couple of years of a deep solar minimum were entirely likely to cause revisions in forecasts. Do you have some supporting evidence as to why you think these 'minority' scientists you speak of would be more likely to be right? I know you state it as 'your opinion', but I'd be curious as to know what you based your opinion on? Or do you simply generally distrust "mainstream" scientists of all flavours, be they astrophysicists or climate scientists? Do you ever think seriously why there may be such a thing as 'mainstream' in a branch of science, given the intellectual/career advantages of finding something new? BTW, whether or not Landscheidt was onto something is neither here nor there - unless you can show that the radiative forcing effect of anthropogenic GHGs is far less than observed and predicted. It may slow greenhouse warming (unlikely to reverse it, the forcing effect is too small) a little for a while, but then when solar activity picks up again, future generations will have to deal with both high GHG (the larger effect) and high solar... sss

I think there are efforts to gather this data, but, to paraphrase the dude from 'Armageddon'... "Mr President, it's a big-ass ocean." Detailed temeprature-depth profiling of the ocean is hard to do at very many localities, and I don't think you can do it remotely (satellites), as you can with atmospheric temperatures. Back to the 'Warming has halted' fallacy... November: record November high temperature December: very nearly record high for December (4th place I think) January: record high January temperature February: looks on UAH to be a clear record high February temperature. Now, where did I put the evidence of 'global cooling'.... :lol: sss

Good post Iceberg - the really important thing is 'regional' versus 'global' climate, Regionally (UK, North Atlantic), we can talk of a >= +1C Medieval Warm Period of sorts, although the maximum is not at the same time everywhere. And In the same regions we can talk of a <= -1C Little Ice Age, frost fairs and the like. But globally, neither event is all that strong, and in many cases is entirely absent from records that ought to show it (ie there is clear 'evidence for absence', rather than 'absence of evidence'). So the combined influence of a strong regional cold plus relatively little effect on the rest of the world is a dilution of the signal, and smaller effect on the global mean temperature, say ~-0.3 to -0.5C for the LIA. It's exactly the reason why the MWP-LIA signal does not show strongly on global summaries of temperature data over the last 1000 years. It's present, only it's less pronounced than those whose historical reference frame is couched in northwest Europe would expect. So a solar change of -0.3C for the Maunder Minimum is entirely reasonable, given historical data, with a little extra impetus to the cold added by volcanic eruptions. Interestingly, if the solar signal was felt relatively strongly in NW Europe, a future solar minimum may affect our temperatures in a comparable way. The difference this time is that the global temperature baseline is rising, and the sources for all our cold air will be warmer than they were previously, as a result of the worldwide warming. Ultimately I would not be surprised to see UK/NW Europe having colder winters than recently in a Maunder Minimum (southerly jet perhaps?), but not with the severity of winters past (note overall record high global temperatures this winter). sss

Just had a report from a friend that 31 inches (75cm) snow has fallen west of Kinloch Rannoch (~200m.a.s.l.) :shok: No plough round yet so those communities are well and truly stuck! Still nothing but cold rain/sleet in Edinburgh...

so one iceberg triggers the release of another one, and somehow it's solar activity and PDO.... oh dear oh dear oh dear... "i dred to think how cold it would have been without it." Weather and climate, we've been over this about a million times. You do understand the concept of weather patterns, the possibility of high snowfalls in warmer air, and not least where we are for global temperature at present? And where we are in relation to the long-term global temperature trend? Moving right on... The whales article is not very good, one thing I'll agree on, but northern hemisphere taking a battering? In terms of unusual weather patterns for parts of the hemisphere, yes, but in terms of low temperatures, a resounding and absolute no! Good fun for the Scottish ski resorts though! sss

This one really is intriguing. All the talk about the Gulf Stream being cut off etc etc was significantly down to fresh water input affecting deep water formation spots in the ocean. So the mechanism is known about, and has been invoked to explain some climate shifts in the past for the NH. The tricky thing is that the deep water formation areas are (so far as I know) very small and localised, so an iceberg the size of Luxembourg may have some impact if it's in the right place. The Heinrich events, however, had vast iceberg armadas pouring into the N Atlantic, so I'd have thought were on a considerably larger scale than this particular berg. I would remain to be convinced that one berg can disrupt AABW formation all on its own, but I guess we're about to find out... sss

I'm a bit concerned that one appears to have been written from a certain perspective (particularly in their assertions of linearity for some concepts), though maybe some of the material may be sound. No time (nor probably the ability) to do a proper critique though, so I'll leave any criticisms to others. Looking around, I found this one, which seems very intuitively right for me and explained a lot of what I didn't get about CO2 concentrations: http://chriscolose.wordpress.com/2010/02/18/greenhouse-effect-revisited/ It has a rather good explanation of why the effect of CO2 is logarithmic, in relation to the spectrum of outgoing longwave radiation. It thus explains beautifully why methane is far more 'effective' a greenhouse gas by the same principle. It explains why small quantities have such a strong impact, and how the saturation effect does not prevent CO2 from being a continuing effective GHG at ever-increasing quantities. sss

Nothing much in Edinburgh, but remaining hopeful for the front returning south. Been pretty nondescript here for the last month. A couple of cms of slush was all we had from an entire morning of wet snow yesterday - once again just the wrong side of marginal. Highlighted by the incidents yesterday, looks like the avalanche hazard will be really high for a while (deep snow and windslab on top of weak layers of frost in places) - I hope mountaineers are sensible and extremely wary of these conditions. Here's hoping the roads can be cleared to get to the ski centres though! sss

I'm afraid my statistical knowledge is far below Tamino's, and most likely yours in this matter, although what Tamino said appeared to make some sense. From Wiki: "Brown [red] noise can be produced by integrating white noise. That is, whereas (digital) white noise can be produced by randomly choosing each sample independently, Brown noise can be produced by adding a random offset to each sample to obtain the next one." This is very like the climate signal. I see your point (3) about linear least-squares regression, though have just read (again on wiki, but I need to be quick here I'm afraid!) that the assumption of "Statistical independence of the observations is not needed, although it can be exploited if it is known to hold." So far as I'm aware (and I may be wrong, hey we all are learning aren't we!), you don't need the data to be entirely independent, but you need to allow for non-independence when calculating confidence limits associated with a trend. Your last point about using means I think is pretty good, though I think the aim of using trends in this case is to highlight the underlying signal of warming, showing that we're on a trajectory at present, and for now have not left that trajectory. In future, we may leave that trajectory in either direction of course. sss

Are you thinking of this one?: Turner et al, 2006: Significant warming of the Antarctic winter troposphere. Science 311, 1914-1917 http://www.sciencema...t/311/5769/1914 [abstract] http://www.sciencema...l/311/5769/1914 [full text, may not be accessible] Looks like observations of remarkable upper tropospheric warmth in Antarctica, as well as stratospheric cooling. They conclude that while this is the pattern expected from GHG warming (no reference annoyingly as I'm really interested in the expected patterns and why), they cannot attribute it directly as the models show too much variability in expected pattern over Antarctica. I wonder, does ozone depletion factor into this (am not sure off the top of my head)? sss

http://tamino.wordpress.com/2009/12/15/how-long/ Speaking of statistical significance in the trend, here's a nice article by the same author discussing how you establish error estimates on a trendline for a temperature timeseries. Because the variability about the mean is autocorrelated (one data point is frequently related to the next), you need to treat the variability as red noise, rather than white noise, and so the standard error margins (1-sigma etc) are larger. What this all means is that in order to determine a trend in the data, you need a bare minimum of 15 years, statistically, to identify your trend in the temperature datasets. Anything less (let alone cherry picking 1998, 2005 or whatever), and you are establishing the slope of the noise rather than the slope of the trend. sss

Interesting points TWS and VP. (BTW, VP, I was aware the data came from Arrhenius and not because you'd missed it out). Just been having a look at the 'polar amplification' issue in a reference from IPCC, and it seems that Holland and Bitz (2003) suggest that much of the amplification is albedo-related, cloud cover may also play a part. http://www.cgd.ucar.edu/oce/pubs/03pubs_files/Holland-ClimDyn.pdf [found in AR4, regional climate] That to me makes sense with sea ice reduction and snowpack reductions in the Arctic, but I wonder about Antarctica. It's a different system altogether with the isolating effect of the circumpolar storms and currents, and with a large ice sheet in the centre, rather than sea ice. Is it the case that the Peninsula warming is as expected, as albedo at those latitudes is affected by sea ice, while the interior's albedo remains little changed as much of it is kilometres-thick ice? There seems to be a lot of uncertainty about Antarctic trends and the reasons why - just not enough hard data. sss

I'm still waiting for the evidence, SC and NSSC. For those suggesting arrogance, I've presented quite a lot of evidence to support my position, and I am entirely willing to view opposing evidence. So far, all I've got is a "I can't be bothered to find it now" approach - why don't you try me (and others) with your evidence? Or are you afraid that it won't stand up to the same scrutiny you expect of all evidence supporting the AGW theory? Are you going to suggest that the trends clearly identifiable in GISS, RSS, UAH and HADCRUT3 are all bunkum? Or any evidence to contradict my opinion the only way you can find a cooling trend is by cherry-picking a massive outlier as your start point: http://tamino.wordpress.com/2009/12/07/riddle-me-this/ Nobody has responded to this one: take the trend from 1980 to 2000, project it forward for the next ten years, and what do you find? Any change? What's the slope on all graphs between 2000 and 2009 (albeit not significant as it's such a short dataset) - is it positive or negative? Please, SC, all I'm looking for is good evidence to support your point of view, but the only way you can suggest the world has cooled is if you use the great 1998 El Nino as your cherry-picked start point. And even that is not the warmest year in all global records. sss

Yes, but opinion gets us nowhere, and runs the risk of seriously misinforming other people. Even some sort of evidence to back up some of the spurious claims of 'no warming' or, 'CO2 not responsible' would be nice, after all, people should have some solid basis for having their opinion. If your opinion is based on whether you feel cold when you jump into the sea, then please forgive me for not taking your opinions as seriously as others! Hopefully your opinion is based on more than just that. For example, looking at: http://www.cefas.co.uk/data/sea-temperature-and-salinity-trends.aspx http://www.cefas.co.uk/data/sea-temperature-and-salinity-trends/presentation-of-results/station-24-weymouth.aspx There's not much evidence for significant cooling post-1998, and the Weymouth data (the nearest one with a long enough timeseries) contradicts your 'feel'. I think Edinburgh feels colder over the last few years, but I'm not taking into account overnight minima, or instrumental observations that are far superior to "it feels colder" or "it feels warmer". And of course Edinburgh's temperatures over a few years have a fractional effect on global climate. It may have been remarkably warm in Yellowknife, Borneo and Timbuktu, but I can't see them outside my kitchen window, but I understand that to get a picture of global climate, I need to know what's been going on in other regions of the world far beyond MBY. sss

If I'm not much mistaken, is this not just indicative of the greater effect of CO2 at higher latitudes, in line with modern thinking? (and there's not data there for latitudes above 70 or below -40). Some evidence there for the greatest change in influence being between 20-40 degrees too, indicating that the tropical regions are least sensitive. Or was there another point you were making? sss