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Comments 120401 to 120450:

120401. Alexandre at 01:49 AM on 25 April 2010
        Has Arctic sea ice returned to normal?
        Marcel #9 Understood. Answering this good question of yours would be the role of a cause attribution study. I think I already saw one about this issue somewhere.
120402. Marcel Bökstedt at 01:40 AM on 25 April 2010
        Has Arctic sea ice returned to normal?
        Ian Forrester> Yes, the submarines give a point in favour of the model. It does not look like a strong confirmation; there seems to be deviations on the order of meters of thickness. Also, it's hard to evaluate the quality of the submarine measurements from the web page. Maybe someone knows more about this? Alexandre> My question was not about AGW or not, but about the connection between the warming of the Arctic and the loss of ice. I just wanted to make the point that this connection might be more complex than what one would immediately assume.
120403. suibhne at 01:15 AM on 25 April 2010
        Where is global warming going?
        chris The anticipated comment to which I refer; The reference is: Joshua Halpern, Christopher M. Colose, Chris Ho-Stuart, Joel D. Shore, Arthur P. Smith, Jörg Zimmermann (2010) Comment On “Falsification of the Atmospheric CO2 Greenhouse Effects within the Frame of Physics”, (to appear in) International Journal of Modern Physics (B), Vol 24, Iss 10, March 30 2010. The six authors put in some hard work to find any alleged "flaws" in the G&T paper. The previous "refutations" unfortunately did not cut the mustard. I for one was rather surprised by the approach of some of previous attempts. I think any reasonable person would agree that it is wrong to prejudge the as yet unpublished comment. If and when it is published however I would expect to have some observations which I will share with the Deltoids.
120404. Alexandre at 00:47 AM on 25 April 2010
        Has Arctic sea ice returned to normal?
        Marcel #5 Scientific papers often use the expression "this is consistent with..." instead of categoric assertions like "this is proof that...". There are lots of evidence pointing to AGW. Arctic ice loss is just one of them. Is it possible that other factors concur (as you rightly pointed out)? Sure. Do we have any evidence of that? Hardly. I think of it like a crime investigation. The accused was seen entering the victim's house before the estimated time of the murder, and a car like his was seen leaving the neighborhood an hour later. The crime weapon was his property, and his hand had the chemical marks of firing the gun. He had the gun when the cops searched him afterwards. The victim had an affair with the accused's wife (there was a motive). Does it prove beyond refutation the accused is guilty? Not quite. We can imagine some unlikely story in which he practiced shooting in his backyard and went to a friendly visit to the victim, and a third party stole his gun for an hour just to make him look guilty. But there's no evidence of this made-up story. On the other hand, do we have enough information to take concrete measures about it (eg convict the accused)? Most likely. Your question is a good one, and maybe some other commenter here knows a cause attribution study about this ice loss. I just feel it's important to keep the issues in perspective.
120405. Ian Forrester at 00:45 AM on 25 April 2010
        Has Arctic sea ice returned to normal?
        Marcel Bokstedt said:

        Zhang's thickness graph above goes back to 1980, but it seems to be based on models, so we only believe it if we believe in those models.

        However, if you read the linked information you will see that Zhang's model has been confirmed by recently released US Naval measurements from it's under polar ice submarine patrols.

        PIOMAS has been extensively validated through comparisons with observations from US-Navy submarines, moorings, and satellites.

120406. Steve L at 00:27 AM on 25 April 2010
        Has Arctic sea ice returned to normal?
        I agree that sea ice extent may not be the best metric of a warming Arctic, and I imagine the choice of the 15% cut-off adds to this, while sea ice volume should be better (given that it can be measured well). But sea ice area is quite important mechanistically in terms of albedo. Therefore I'm fine with skeptics focusing on extent. It will come back to bite them in the end, though, since you can only spread a given volume so thin.
120407. Sean A at 00:26 AM on 25 April 2010
        The significance of past climate change
        "Using ice cores, we can work out past temperature change, the level of solar activity plus the amount of greenhouse gases and volcanic dust in the atmosphere." A bit of explanation on how all that information can be gleaned from ice cores might be helpful. Isn't this an important feedback... in the past, during a warming trend, increasing temperatures caused the oceans to release dissolved CO2, which caused further warming.
120408. Marcel Bökstedt at 00:20 AM on 25 April 2010
        Has Arctic sea ice returned to normal?
        When you look at graphs of Arctic sea ice extent plotted against time, graphs like the one John posted above, two conclusions seem visually obvious. There are very large random fluctuations, and there is a very clear long term decreasing trend. Because of the large short time variations, I don't think that one shoud be too impressed by either the sea ice minimum of 2007 or by the alleged recovery. These could be random events, and do not touch the long term trend. The available data on ice thickness are strongly suggestive, but they only span about 5 years. Because we already know that we have to deal with strong short time variations, it is not clear to me that they do represent a long term trend. Zhang's thickness graph above goes back to 1980, but it seems to be based on models, so we only believe it if we believe in those models. Still, the data on ice extent very clearly points to a trend towards less ice. The most obvious explanation would be global warming. But is it certain that this decrease is linked to that - yes, it does sound like a very foolish thing to say, but after all, we know that the situation in the Antarctic sea is very complicated. The sea around Antarctica is warming, but the extent of ice in that warming water is increasing. There are several interesting attempts to explain this, including a subtle model by Jinlun Zhang et al., but I don't think that we really understand what is going on there. If we don't understand the dynamics of ice around Antarctica, how can we be sure that we understand the dynamics of ice around the North Pole?
120409. Alexandre at 00:16 AM on 25 April 2010
        Has Arctic sea ice returned to normal?
        Watts -as most deniers- is a cherry picker. I remember when he cheerfully tried to capitalize on the 2008 La Niña temperature drop, and now totally ignores the recent temperature rise. Many people believe him, but that's just the human problem of sticking to anyone that says what one wants to listen. It does not have anything to do with the quality of data, or accuracy of analysis.
120410. Ken Lambert at 00:03 AM on 25 April 2010
        Tracking the energy from global warming
        BP #72 Your post #67 explains that the last 6 years (2004-2010) of the TOA curve in your G62 graph is the same shape as the G60 graph (slightly negative trend slope) except that the G62 is sitting on a linerr positive trend slope which represents a systemic offset error in the CERESFlash TOA flux. Right? I subtract the two trend slopes and come up with a positive slope difference which equates to 1.11E22J/year which equates to a TOA flux error of +0.69W/sq.m Is not that an estimate of the 'large and unknown' CERES TOA flux error, derived from your G60 and G62 graphs? We all agree that CERES tolerances of 2 +/-5 W/sq.m is a useless number for evaluating radiative forcing imbalances. You have said that CERES TOA is high precision but low accuracy, meaning that it is good for relative measures wrt time, but no good for absolute numbers. You claim that the 2004-10 Argo OHC measurements are the opposite - presumably no good for relative time series comparisons but good for absolute numbers. So if your G60 graph is meaningful - it does provide a way of calibrating the CERESflash TOA flux with an absolute number derived from assuming that Argo measured OHC heat (top 700m) energy absorbed equals the integral of the CERESflash TOA flux. Right? If that is not right, please explain why. Your last papagraph in #72 is confusing - "Effective temperature of Earth as seen from space should have decreased by 0.15 °C if climate sensitivity is 3 °C for carbon dioxide doubling as claimed." Did you mean 'increased by 0.15 degC' for a 5% CO2 increase and that equates to 0.56 W/sq.m extra energy flux imbalance at TOA? Was this a sardonic remark doubting the existence of the 0.56 W/sq.m of extra radiative forcing from 5% increase in CO2? You also have a major problem with von Schukmann finding lots of heat down to 2000m from the Argo buoys. I noticed that Dr Trenberth has already used this VS paper as evidence for his 0.45W/sq.m (0.9 postulated and 0.55 found)of missing heat in his email exchange with Dr Pielke Snr. What about mechanisms like the thermohaline circulation to get heat down to 2000m in these short timeframes?? BP, I think you are on the right track with your posts, so please expand your ideas into language more accessible to the non-expert climateer (dumber engineers like me). You might yet be the man to crack the AGW case..
120411. HumanityRules at 23:56 PM on 24 April 2010
        Has Arctic sea ice returned to normal?
        A genuinely puzzling question. If ice volume is a better gauge of arctic sea ice and if the trend is more worrying why is this not regularly used as the standard for measuring arctic sea ice condition? The way you word things it sort of suggests that WUWT are cherry picking the ice extent to tell a certain story. But most of the serious science website that provide day-to-day arctic sea ice coverage focus on ice extent as well (NSIDC, arctic roos, DMI, cryospere today etc). Are there uncertainties with measuring ice volume?
120412. Marcus at 23:24 PM on 24 April 2010
        Has Arctic sea ice returned to normal?
        Also, I do find it amusing that the skeptics leap on a single years worth of "good" news to prove their point, yet they're the quickest to dismiss even a few years of *bad* news, claiming its insufficient to prove a trend. They certainly score zero points for consistency ;)!
120413. Marcus at 23:22 PM on 24 April 2010
        Has Arctic sea ice returned to normal?
        As I understand it, one of the key problems with a reliance on sea-ice extent is-whilst you may have one good year of ice recovery-that this ice will be relatively new & thus more prone to melting come the next Summer. As I also understand it, what concerns scientists is the lack of multi-year ice. For my part, when non-specialized trade vessels can sail the extent of the North-West Passage-in late Autumn-then there is something to be concerned about!
120414. chris at 19:08 PM on 24 April 2010
        Where is global warming going?
        re: suibhne at 18:03 PM on 24 April, 2010 Not really suibhne. Arctic sea ice is on a downward trend. Sea ice area coverage will obviously show considerable interannual variation; however as the downward trend progresses strongly warming years will eat into old ice which requires several sufficiently cool years to recover, and so sea ice volume is likely to be diminishing without the amount of interannual variability of sea ice area. Thus, as pointed out by Peter Hogarth evidence indicates that total sea ice (i.e. sea ice volume) in March was the lowest March sea ice volume on record: Polar Science Center, Univ. Washington re: suibhne at 18:12 PM on 24 April, 2010 suibhne, jibal was referring to your curious reluctance to address straightforward questions on the Deltoid thread. He wasn't referring to the in press comment on the dodgy IJMBP paper.
120415. suibhne at 18:12 PM on 24 April 2010
        Where is global warming going?
        jibal at 16:48 PM on 22 April, 2010 Jabal refers to another site where the imminent release of a comment by Halpern, Smith, Colose and three others was promised (March 20). As this has not happened as yet it might out of courtesy to them be better to wait for its release. http://scienceblogs.com/deltoid/2009/03/gerlich_and_tscheuschner_oh_my.php
120416. suibhne at 18:03 PM on 24 April 2010
        Where is global warming going?
        James Wight 37 Your figures for Arctic Sea Ice may need an update. Now highest for last 8 years. http://wattsupwiththat.com/
120417. damien at 14:16 PM on 24 April 2010
        Skeptical Science Housekeeping: flags, printable versions, icons and links... lots of links
        This repository is awesome. Can you publish statistics on the number of articles published in each "camp" for comparative purposes? For example a plot of number of articles in a category for each month, with the option of comparing graphs side by side. Also, it would be helpful for the Peer Reviewed articles if it listed the actual journal/conference it was published, not just springerlink.com, which could be any number of journals.
120418. kdkd at 13:42 PM on 24 April 2010
        Tracking the energy from global warming
        I'm really not convinced of the validity of treating a stochastic system as if it deterministic. Seeing as the OHC/TOA system is certainly part of a stochastic system, we'd need a good bit more data than 9 annual cycles (the annual cycle should be the basic unit of analysis here) in order to understand properly the contribution to the climate system. Given the similarities with the global temperature record (another part of the system), around 30 years of data would be a bare minimum with which to reach robust conclusions.
120419. Berényi Péter at 13:01 PM on 24 April 2010
        Tracking the energy from global warming
        #70 Ken Lambert at 23:45 PM on 23 April, 2010 This converts to a systemic error of +0.69W/sq.m in the CERESflash flux. I don't think so. The systematic error is large and unknown. Net flux at TOA is estimated to be 2 ± 5 W m^-2, i.e. even the sign is doubtful. In this sense TOA flux is not measured at all by CERES. However, interannual variation is much better constrained. The large difference between figures in #60 & #62 comes from OHC. The transition around 2003 from MBT/XBT stuff to ARGO has a huge intercalibration problem. That is how the "missing heat" was produced. If the unknown offset of CERES FLASHFlux is aligned to the early 21th century OHC data, one gets a positive slope but poor fit with much missing thermal energy by the end of this decade. On the other hand, if it is done the other way around and FLASHFlux is aligned to the late part of OHC, the fit is excellent except before mid 2003. In this case we do not have any recent "missing heat", but excess heat before 2003. My guess is the thermal energy was there, in the upper 700 m of oceans, just was not measured properly (e.g. in southern Pacific). In this case one does not have to invent mysterious processes transferring heat into the abyss directly through a 700 m deep cooling layer. What is more, this process would only carry heat, but not dissolved carbon dioxide. After all CO₂ deep mixing is supposed to be extremely slow. So far so good. However, we still have a problem. Not with measurement, but with theory. OHC and net TOA flux measurements can be made consistent, but at a price. We have a negative energy balance for the last six years. The climate system is not gaining energy, but losing it. A -118 mW m^-2 rate may not sound much, but is enough to bring havoc to standard greenhouse theory. It is about the decrease in TSI (Total Solar Irradiance) due to weak and late cycle 24. But wait, CO₂ has increased from 375 ppmv to 389 ppmv between 2003 & 2010. The change in radiative forcing during this period is about 5% of a CO₂ doubling. Effective temperature of Earth as seen from space should have decreased by 0.15 °C if climate sensitivity is 3 °C for carbon dioxide doubling as claimed. It is equivalent to a positive energy imbalance of 560 mW m^-2 at TOA, which is not seen.
120420. Alexandre at 07:55 AM on 24 April 2010
        Skeptical Science Housekeeping: flags, printable versions, icons and links... lots of links
        Now that we don't have that "skeptical article of the week" anymore, how's the argument ranking position defined?
        Response: On the latest articles page, they're ranked by date from latest to earliest.
        
        If anyone misses the Skeptic of the Week feature, I can easily add that back in - I just commented out the code.
        
120421. chris at 07:11 AM on 24 April 2010
        Earth's five mass extinction events
        batsvensson at 05:15 AM on 19 April, 2010 batsvensson, I told you in detail why I reject your idea. If you don't agree, you really need to say why! If you can "imagine" "scenarios" "which (my) list seams not to contradict", you really need to tell us what these scenarios are. We can hardly be expected to address ideas that are in your "imagination", that you don't tell us about. We aren't mind-readers!
120422. chris at 06:27 AM on 24 April 2010
        The significance of past climate change
        Steve Berry at 04:57 AM on 24 April, 2010 Steve, the Earth's thermal energy comes almost exclusively from the sun (a tiny amount from radioactive decay within the Earth). Since greenhouse gases are largely transparent to solar radiation of the energies that directly impact the atmosphere and the Earth, enhanced greenhouse gases don't have much of an effect on incoming solar radiation, which impacts those regions of the Earth's atmosphere and surface that are facing the sun (i.e. during daylight hours). On the other hand radiative equilibrium (largely constant Earth surface temperature) is achieved by the incoming solar radiation being balanced by radiation returning to space. Some of this occurs by reflection [from the atmosphere, or clouds or highly reflective (high albedo) Earth surface, especially surface ice]. A large part of the radiation returning to space is that which is emitted from the Earth's surface. This is long wave infra red (LWIR), that is emitted by all bodies that have temperatures above zero Kelvins. It is this thermal radiation that is "trapped" by greenhouse gases and which warms the atmosphere. LWIR is an inherent property of all warm bodies, and occurs continuously, including during the night. So whereas daytime temperatures are dominated by the incoming solar radiation (depends on incident angle; i.e. seasonality) and reflective cloud cover, night time temperature variability is dominated by warmth trapping cloud cover and the efficiency of emission of LWIR back to space. All else being equal (i.e. solar irradiation, albedo and cloud cover), in a world with continuously rising greenhouse gas concentrations, we expect the night time temperatures to increase faster than day time temperatures, since LWIR is only one of several contributions to loss of thermal energy to space during the day, whereas it is a dominant factor in night time heat loss. This isn't the whole story. In a warming world we might expect to observe somewhat higher cloud cover at night, since enhanced atmospheric temperatures means more atmospheric water vapour with possible enhanced cloud formation as the atmosphere cools at night. On the other hand, man made increases in atmospheric greenhouse gases is accompanied by enhanced atmospheric aerosols, and this tends to decrease solar radiation at the Earth's surface, reducing the night/day warming difference...
120423. Tom Dayton at 06:22 AM on 24 April 2010
        The significance of past climate change
        RSVP, greenhouse gas radiation does not cancel out, because the gas acts as layers instead of a single slab. Each layer radiates in all directions. When a layer has another layer above it, that upper layer in turn intercepts the radiation that is headed toward space, then radiates it in all directions, including down. I'll not finish the explanation here, because you can read it on Spencer Weart's Simple Models of Climate page. Use your browser's Find function on that page to find the text "shorthand way," and read down from there.
120424. physicalscientist at 06:22 AM on 24 April 2010
        Skeptical Science Housekeeping: flags, printable versions, icons and links... lots of links
        John - Thank you very much for the collated links to peer-reviewed papers. This is a valuable service and it will be very helpful for students and others less familiar with the list of reputable journals to find appropriate material. Don't worry too much about the skeptic, neutral, pro-AGW classifications, we can figure it out. Although I would probably fall in the 'pro-AGW' camp, I definitely am not really pro-AGW. It actually would be much better if the deniers were right and we had nothing to worry about. Unfortunately, we definitely do.
120425. KR at 05:05 AM on 24 April 2010
        The significance of past climate change
        Unrecovered, here where you talk about understanding positive feedback, you have a good point. Many people seem to assume that positive feedback is unstable. One way to explain this is to note that positive feedback results in the system moving further from the starting point than the unmodified forcing would take it. That extra change causes more feedback, and so on, and so on. If the feedback is <1x the change, each successive feedback amount is smaller, and the sum of all the changes damps out. If the feedback is >1x the change, however, each iteration of feedback will be larger, and the system will run away (until some other form of feedback limits matters). Fortunately the vast majority of systems are stable - I suspect unstable ones just blow up when they arise.
120426. Steve Berry at 04:57 AM on 24 April 2010
        The significance of past climate change
        Can someone explain to me why most of the observed global surface warming of recent decades is occurring mostly at night? Why, if CO2 is a warmer, is it that daytime temps have remained pretty much stable, but nighttime temps have risen? Wouldn't this indicate that increased cloudiness is a major factor? Thanks.
120427. RSVP at 04:45 AM on 24 April 2010
        The significance of past climate change
        Incremental CO2 in the atmosphere could just as easily act as a staging for additional IR radiation. Why not then consider this as providing as much negative feedback as positive feedback (basically resulting in a net canceling towards warming)?
120428. garythompson at 03:47 AM on 24 April 2010
        The significance of past climate change
        #73 chemware - if you were to plot the average global monthly surface temperatures anomolies from HADCRUT3 vs. Mauna Loa average monthly CO2 concentrations you would not get a very nice correlation. from 1958 to 1974 there was a flat response, followed by a linear reponse (and what appears to be good correlation) then back to a flat response in 1999 which continues today. it just shows there are other variables at play here.
120429. Chris G at 03:16 AM on 24 April 2010
        The significance of past climate change
        Mikko, good point, I try to make point this out whenever I hear complaints about cows or local grassland burning. Chemware and Barry, Interesting graphs, but I think there are a couple of major flaws, one each per graph. On the temp graph, it's pretty well established that temperature response is logarithmic, and you have applied a linear best-fit. Hansen tends to be on the upper end of estimates for long-term equilibrium response, and I think he's estimating about 6 K for a doubling of CO2, under current planetary conditions. Aside from thermal expansion, there is a hard limit of how much sea levels can rise that is determined by how much ice there is to melt. Even if you accept that the earth will eventually be ice-free if a 450 or greater ppm level is maintained, there's only about 80 m of ice available. In contrast, you graph is off the chart at 450 ppm. http://pubs.usgs.gov/fs/fs2-00/
120430. bookworm at 02:48 AM on 24 April 2010
        The significance of past climate change
        might be useful to look at the reverse situation. If climate had NOT changed significantly in the past, change skeptics would then be arguing that man could not possibly have any effect on world climate - that climate is self correcting in response to various challenges. The only overall conclusion from the fact of past change is that future change is possible. As other posts have pointed out the skeptic argument above is really a non-sequitur. reversing the situation helps people understand that. Only then get into the details - discussions of time scales and the like.
120431. kdkd at 23:54 PM on 23 April 2010
        Tracking the energy from global warming
        Just to confirm, if I annualise the TOA/OHC data rather than have it in quarters like at the moment (actually over 9 years), neither the regression nor the correlation give statistically significant parameter estimates due to the loss of statisical power.
120432. Ken Lambert at 23:45 PM on 23 April 2010
        Tracking the energy from global warming
        BP #67 Think I have got it. Excuse my slower engineer's brain. If we can name your charts Graph #60 and Graph #62, then am I right in assuming that your G#60 is the 'right' measure of OHC because the integral of the TOA flux fits the Argo 700m OHC? If so, then the diffence in slopes of the TOA integral between G#60 and G#62 represents the systemic error in the CERESflash flux. Taken over the last 6 years, your G#60 slope is -0.19E22J/yr and the G#62 slope is about +0.92E22J/yr with the difference being about 1.11E22J/yr. This converts to a systemic error of +0.69W/sq.m in the CERESflash flux. Could you then suggest why the 2000 - 2004 part of your G#62 TOA curve has a pretty flat slope of about 0.25E22J/yr, implying a much lower systemic error or if the error is constant at +1.11E22J/yr; a large decline in OHC for 2000-2004?
120433. James Wight at 23:44 PM on 23 April 2010
        Skeptical Science Housekeeping: flags, printable versions, icons and links... lots of links
        Do the dates refer to the date the article was added to the database, or the date the article was published?
        Response: Published. It automatically prefills it with the current date but you can manually update it. It's not that big a deal for recent blog posts or mainstream media posts but for peer-reviewed papers published in previous years, good to get the year correct.
        
120434. chris at 22:11 PM on 23 April 2010
        Where is global warming going?
        Yes, fine Peter, but it still doesn't address the point. If we want to assess Arctic surface temperatures as mspelto's point related to, then your response that "The "Arctic" has only one active GHCN station in Canada" is a non-sequitur. If we want to assess Arctic temperatures then the full set of Arctic temperature station data and satellite sea suface temperature data for the Arctic should be used (in fact the method by which NASA Giss assesses Arctic temperatures means that the Arctic data has some distance-scaled contributions from non-Arctic sites. I don't know the reason why Eureka was dropped. if you find out I'm sure we'd all be interested to know...
120435. Berényi Péter at 21:46 PM on 23 April 2010
        Where is global warming going?
        #47 chris at 17:33 PM on 23 April, 2010 Peter, I was addressing your non sequitur I have mentioned Canada because GHCN artic station dropoff is most serious in that country. But we can get more specific if you wish. I have pulled off most recent GHCN v2 data at 2010-04-23 08:00 UTC from the GISSTEMP site. There are 108 stations in the database north of the Arctic Circle (66.5619° N). The distribution according to 1° latitude bands is as follows: 66 8 67 13 68 25 69 15 70 13 71 5 72 6 73 4 74 2 75 1 76 6 77 2 78 3 79 2 80 1 81 1 82 1 According to country: CANADA - 43 RUSSIAN FEDERATION (ASIAN SECTOR) - 25 NORWAY - 15 GREENLAND (DENMARK) - 10 UNITED STATES OF AMERICA - 7 RUSSIAN FEDERATION (EUROPEAN SECTOR) - 3 FINLAND - 3 SWEDEN - 2 Of these 108 stations 38 (35.2%) can be considered "active", ie. having data for January-March 2010. Latitudal bands: 66 2 (25% / 8) 67 5 (38.5% / 13) 68 8 (32% / 25) 69 4 (26.7% / 15) 70 5 (38.5% / 13) 71 2 (40% / 5) 72 1 (16.7% / 6) 73 1 (25% / 4) 74 2 (100% / 2) 75 0 (0% / 1) 76 2 (33.3% / 6) 77 1 (50% / 2) 78 1 (33.3% / 3) 79 2 (100% / 2) 80 1 (100% / 1) 81 1 (100% / 1) 82 0 (0% / 1) Country: CANADA - 6 (14% / 43) RUSSIAN FEDERATION (ASIAN SECTOR) - 17 (68% / 25) NORWAY - 7 (46.7% / 15) GREENLAND (DENMARK) - 3 (30% / 10) UNITED STATES OF AMERICA - 2 (28.6% / 7) RUSSIAN FEDERATION (EUROPEAN SECTOR) - 2 (66.7% / 3) FINLAND - 0 (0% / 3) SWEDEN - 1 (50% / 2) As you can see, station dropout rate in Canada Arctic is 86%, pretty high. I would rather not go into arcane details, just consider a single case, Alert, Nunavut. It is the northernmost permanently inhabited place in the world with not just an operational weather station, but also part of Global Atmosphere Watch. Still, it was dropped from GHCN in September 1991. It is not that data are not available. One can even download them in tabular format from Weather Underground for free. The closest active GHCN station is Eureka, 480 km away. Can you think of any valid reason it was dropped?
120436. chris at 19:59 PM on 23 April 2010
        The significance of past climate change
        Chemware at 09:53 AM on 23 April, 2010 I'm not sure how seriously you're taking your graphs, but they're not teriibly helpful in relation to the expected/anticipated response of the climate system (temperatures; sea levels) to raised CO2 levels. The first graph tells us something about the response of the carbon cycle to raised earth temperature, and more specifically the temperature-induced redistribution of CO2 from ocean and terrestrial stores into the atmosphere. Your data indicates that if Earth temperatures rise by 1 oC, then the equilibrium atmospheric [CO2] levels rise by around 20 ppm. Since the glacial to interglacial earth temperature rise is 5-6 oC globally averaged and the glacial to interglacial [CO2] increase is around 90 ppm (from 180 ppm glacial to around 270 ppm interglacial), we get 15-18 ppm of increased [CO2] from a 1 oC temperature rise through glacial cycles; pretty much in line with your plot. (It's not quite so simple, since one must also factor in the feedback warming from the raised [CO2]. A similar problem arises with your sea level plot. Sea levels respond to temperatures. One can relate these causally to [CO2] levels only under the circumstance that the dominant influence on temperature is [CO2] changes (as is largely the case now). That wasn't the case during glacial-interglacial cycles, so the second plot has the same flaw as the first...
120437. Riccardo at 17:58 PM on 23 April 2010
        Models are unreliable
        cloneof, you might be interested in this paper in press which specifically addresses Spencer and Braswell 2009 and to this discussion. Thanks to Ari Jokimäki at AGWObserver for informing us on this not yet published paper.
120438. chris at 17:33 PM on 23 April 2010
        Where is global warming going?
        gallopingcamel at 13:53 PM on 23 April, 2010 No the NASA link is current right through to the present. Click on the Arctic region of the map on the NASA page I linked to. You will get lists of all the stations within 1500 km, and can select those that are Arctic ( >66 o N), and can discover which ones have data through 2010. There are quite a lot of these. The NASA Giss temperature for the Arctic is based on the full set (not just Eureka and Resolute). Berényi Péter at 15:41 PM on 22 April, 2010 Peter, I was addressing your non sequitur. If we want to address Arctic temperature station coverage, we should addres Arctic station coverage, not just Canadian Arctic station coverage..
120439. Mikko at 17:05 PM on 23 April 2010
        The significance of past climate change
        The argument: "Rising CO2 levels are an external forcing" would be easier to understand if you emphasize that the extra carbon is coming from sources of stocks of fossil carbon i.e. the carbon is coming in to the system (biospehere) from external sources (“carbon is coming into the system from under ground”). That is what is different in burning trees than burning fossils. In the first case you burn carbon that is already in the system (internal carbon). In the second case you burn carbon that is not in the system (external carbon).
120440. Ari Jokimäki at 14:54 PM on 23 April 2010
        Skeptical Science Housekeeping: flags, printable versions, icons and links... lots of links
        Also, the "Latest climate articles & papers" could use an "all" option to all search parameters.
120441. Ari Jokimäki at 14:51 PM on 23 April 2010
        Skeptical Science Housekeeping: flags, printable versions, icons and links... lots of links
        There was one thing I was missing. You used to have a good set of links to useful websites and such in the "Links" page but now it just contains the argument links. I just noticed that in the bottom of the Links-page there is a link that says "Links" which leads you to the old Links-content. That should be more visible somehow, I think.
        Response: I'll add it to the navigation drop down. Am going to have to come up with better names for everything - I can't call all these different pages "Links".
        
120442. gallopingcamel at 13:58 PM on 23 April 2010
        Where is global warming going?
        It just struck me July 13 is the eve of Bastille Day. Given that we are talking about Canada, could there have been some celebrating going on?
120443. gallopingcamel at 13:53 PM on 23 April 2010
        Where is global warming going?
        Chris (#39), The NASA link you provided cuts off at the year 2000 so you should look at more recent information: http://diggingintheclay.blogspot.com/2010/01/station-drop-out-problem.htm Ned has challenged me to find the reasons behind the station drop offs. With this in mind I am planning a trip to North Carolina during May. My correspondence with staff members at NOAA, Asheville and Environment Canada is going well but I still don't understand why so many stations have "dropped off". With regard to the Canadian Arctic, by 2004 only Eureka was left in the GHCN v2. Resolute appears to be back but I overlooked it as the station number changed. One of the problems with having so few stations is that METAR data errors can cause huge changes in NASA's anomaly maps of the polar regions. Berenyi Peter has already pointed to the "huge anomaly" of about 4 degrees Celsius for polar regions in March 2010. This anomaly may result from some strange readings at Eureka on March 29. This issue popped up on WUWT today. They found something similar on July 13, 2009: http://wattsupwiththat.com/
120444. kdkd at 11:38 AM on 23 April 2010
        Tracking the energy from global warming
        I'm still not sure that I understand this TOA/OHC stuff properly. So here's what I've done to BP's spreadsheet though: First to get OHC and TOA in the same units, I standardise them so that the mean is 1 and the standard deviation is 1. Now I run a linear regression model which comes out as: std(OHC) = 0.5 X std(TOA) + 1.4 E10-16 So for every unit that OHC increases, TOA decreases by 0.5. The adjusted R squared for this regression model is 0.22 indicating that TOA predicts 22% of the variance of OHC. The F statistic for the regression is 11.8 (df=1,37) indicating that the regression predicts better than chance. Next I move over to correlation because for a single variable correlation, it's equivalent, and slightly easier to understand. So the correlation between the two variables is -0.49 (p < 0.01) which is strong enough to convince me that autocorrelation isn't an especially big problem, although I lack the knowledge to examine that formally. The 95% confidence interval of the corelation is between -0.70 and -0.21. So what I want to do next is compare the performance of this regression against the UAH satellite data for tropospheric temperature anomaly. Again using standardised data for the 29 years data I have for the satellite record, the formula for predicting standardised temp anomaly from standardised atmospheric co2 is: std(temp) = 0.62 * co2 + 0.3E16 F(df=1,27) = 16.79, p < 0.001 Adjusted R squared is 0.36 The correlations are: 0.62 (95%CI = 0.32 - 0.80) So with 30 data points we're getting a similarly good prediction of some measures of the response to some climate variables to the OHC/TOA data. Now I don't have quarterly data easily to hand for the sattelite data or co2 levels, but I can just look at the final 10 years in the series to see how good that is. However for the data that I have to hand, with only 10 observations, the statistical power is so poor that the regression and correlation is not statistically significant. My conclusion is that the TOA/OHC data that BP presented is what we would expect for a moderately sensitive system with only a small number of data points - and thus limited statistical power. I don't think there's enough data to be able to draw conclusions about the relationship between OHC and TOA to global warming until quite a lot more data comes in. Meanwhile we need to rely on the temperature data, and the associated measures (e.g. ecosystem sensitivity etc) in order to use scientific data to formulate policy.
120445. HumanityRules at 10:45 AM on 23 April 2010
        Tracking the energy from global warming
        67.Berényi Péter The OHC variablity looks seasonal. Have you tried averaging over a year? "On the other hand, net TOA flux should be very close to proportional to the time derivative of OHC, because there is no other heat reservoir in the climate system with comparable storage capacity." I started to think about the ability of the ocean to release energy. It's easy to imagine that at different times the rate at which energy is lost from the ocean varies allowing build up or loss of energy on a short time period which doesn't always match the incoming energy.
120446. Chemware at 09:53 AM on 23 April 2010
        The significance of past climate change
        #55 Barry: very nice analysis and data, but it only covers the last 150 years. So the temperature is not in equilibrium as [CO2] is rapidly changing, and the whole climate system is far from equilibrium. That is, if we stopped emitting CO2 right now, the temperature would continue to climb for several decades-centuries. I was after the long-term, equilibrium temperatures, which I think are best obtained from paleo data, because the [CO2] is changing very slowly, and the climate is close to equilibrium. #57 Barry: Yes, this is the Vostok data, which I simply re-graphed to plot Temperature as a function of [CO2], over the last 100 kYears. #67 Chris: Yes, the same old Vostock data, combined (in Fig 1A) with Red Sea sea level data. But simple-minded experimentalist me has just taken the next step and said that if Temperature and Sea Level correlate with [CO2] (as Hansen's graphs clearly show), then let's just plot them against [CO2]. This is shown below. Re-plot of Vostok Ice Core data Plot of Bard's sea level data against Vostock CO2 data These are the sort of graphs that Engineers love: if [CO2] is X ppm, then I need to design for a Temperature of Y C, and a Sea Level of Z m. While one must always be extremely careful with extrapolation, the goodness of fit and the slope of both graphs is very worrying.
120447. johnd at 08:26 AM on 23 April 2010
        Flowers blooming earlier now than any time in last 250 years
        Given the First Flowering graph was based on UK data I wanted to relate the days of the year to how the seasons progress here in south eastern Australia. Here the autumn equinox happens on day 80, winter solstice on day 172, spring equinox on day 266, and summer solstice on day 356. In the northern hemisphere it follows that spring equinox happens on day 80, summer solstice on day 172, autumn equinox on day 266, and winter solstice on day 356. That means that day 140 on the first flowering index falls a full 60 days after AFTER the spring equinox and just 32 days before the summer solstice. That is certainly different to what we are used to on this opposite side of the world with the first flowering expected weeks BEFORE the Spring equinox. It would seem then that conditions that are global such as the solstices and equinoxes are less relevant than perhaps local conditions. Perhaps it comes down to the plants themselves, or the composition of the species, more spring flowering plants and less summer flowering. I realise it is the relative change that the article focuses on, but given the obvious differences between different parts of the world, it seems to be stretching credibility quite a bit to assume it represents what is occurring globally.
120448. scaddenp at 07:04 AM on 23 April 2010
        Skeptical Science Housekeeping: flags, printable versions, icons and links... lots of links
        John, I might be missing the obvious but how do you find these links from the main page? Its not obvious to me. I would have expected this under Links (Resources) page, but no go. Is this just failing eyesight?
        Response: The navigation system needs a serious overhaul - hopefully the next housekeeping effort will include a bunch of navigation dropdowns drilling directly to all these hidden nooks and crannies.
        
120449. scaddenp at 06:45 AM on 23 April 2010
        Greenland's ice mass loss has spread to the northwest
        Acushla - I think you are being suckered by misinformation. There are good historical documents for the Greenland colony - confined to 2 southern fiords and plenty of archeological evidence about the settlement too. The ice sheet was firmly in place then, as now. There is no possible doubt about this.
120450. Jim Eager at 03:39 AM on 23 April 2010
        Skeptical Science Housekeeping: flags, printable versions, icons and links... lots of links
        VoxRat, you have to set the three search parameters at the top your self.

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