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Comments 116651 to 116700:

116651. Lon Hocker at 11:47 AM on 27 June 2010
        Is the long-term trend in CO2 caused by warming of the oceans?
        Oops, should have been "increases the uptake" instead of "reduces the uptake"
116652. Lon Hocker at 11:45 AM on 27 June 2010
        Is the long-term trend in CO2 caused by warming of the oceans?
        Peter: Thank you for the excellent comment. I agree with pretty much everything you wrote. The carbon ratios support the emission of CO2 from the equator and absorption near the poles with a half time of about 5 years, regardless of model, as long as you accept the 100GtC flow. No question that there is a net flow of CO2 into the ocean from anthropological sources. The higher atmospheric CO2 due to anthropogenic sources reduces the amount that would have been emitted by the ocean for the same temperature increase (and decreases the uptake), and that would have been a clearer description than my stating that it came from the oceans. With a 5-year tome constant, the anthropogenic contributions to the CO2 increase would be about 25% of the observed increase, leaving the rest for the temperature change. I realize that this is an emotional subject for all, and I likely would have been more politic to not have written such a aggressive headline! In any event the science is far from settled, and I wanted to present a contrasting argument to that usually accepted. I greatly value postings, such as yours, that provide information and opinion dispassionately . I know that my understanding of this is far from complete, and I am open to changing my mind on pretty much everything, except for the Mauna Loa and satellite data, and my understanding of math and calculus! Again, thank you, and I would enjoy hearing more of your perspectives.
116653. Berényi Péter at 11:03 AM on 27 June 2010
        Temp record is unreliable
        #61 Ned at 00:20 AM on 5 April, 2010 The close agreement between satellite and surface temperatures is a bit of a problem for those skeptics who believe that the surface record is hopelessly contaminated by UHI effect Ned, the problem with satellite "temperatures" is that satellites do not measure temperature, not even color temperature, but for a specific layer of atmosphere (e.g. lower troposphere) brightness temperature is measured in a single narrow IR band. This measurement may be accurate and precise, but it is insufficient in itself to recover proper atmospheric temperatures. In order to make that transition, you need an atmospheric model. With the model atmosphere you can calculate the brightness temperature backwards and tune parameters until a match is accomplished with satellite brightness temperature data. Then you can look at the lower troposphere temperature of the model and call it temperature. However, with no further assumptions, the relation is not reversible, i.e. many different atmospheric states lend the same brightness temperature as seen from above. The very assumptions in the model, that make reverse calculations possible are the hidden backlink to surface temperature data. For there is no other way to verify model reliability than compare it to actual in situ measurements. Therefore if the surface temperature record is unreliable, so are atmospheric models used to transform satellite measured brightness temperatures to atmospheric temperatures. That makes the whole satellite thing dependent on surface data, in spite of independent sensor calibration methods.
116654. Doug Bostrom at 10:24 AM on 27 June 2010
        IPCC were wrong about Amazon rainforests
        Resurrecting "Amazongate?" Now, I am not saying that the claim is wrong. I do not know whether it is or not. But you'll bring it up because it's handy rhetoric. IPCC has something like a "four nines" reliability record with cites, so dredging up this silliness is only going to continue playing badly for those using it for impressionist art purposes. Read what Nepstad himself had to say. Senior Scientist Daniel Nepstad endorses the correctness of the IPCC’s (AR4) statement on Amazon forest susceptibility to rainfall reduction: "The IPCC statement on the Amazon is correct, but the citations listed in the Rowell and Moore report were incomplete. (The authors of this report interviewed several researchers, including the author of this note, and had originally cited the IPAM website where the statement was made that 30 to 40% of the forests of the Amazon were susceptible to small changes in rainfall). Our 1999 article (Nepstad et al. 1999) estimated that 630,000 km2 of forests were severely drought stressed in 1998, as Rowell and Moore correctly state, but this forest area is only 15% of the total area of forest in the Brazilian Amazon. In another article published in Nature, in 1994, we used less conservative assumptions to estimate that approximately half of the forests of the Amazon depleted large portions of their available soil moisture during seasonal or episodic drought (Nepstad et al. 1994). After the Rowell and Moore report was released in 2000, and prior to the publication of the IPCC AR4, new evidence of the full extent of severe drought in the Amazon was available. In 2004, we estimated that half of the forest area of the Amazon Basin had either fallen below, or was very close to, the critical level of soil moisture below which trees begin to die in 1998. This estimate incorporated new rainfall data and results from an experimental reduction of rainfall in an Amazon forest that we had conducted with funding from the US National Science Foundation (Nepstad et al. 2004). Field evidence of the soil moisture critical threshold is presented in Nepstad et al. 2007. In sum, the IPCC statement on the Amazon was correct. The report that is cited in support of the IPCC statement (Rowell and Moore 2000) omitted some citations in support of the 40% value statement.
116655. Willis Eschenbach at 09:38 AM on 27 June 2010
        IPCC were wrong about Amazon rainforests
        Riccardo, thanks for the links. The WWF document cites the Nature document (Nepstad 1999) as their source for the statement that

        "Up to 40% of the Amazonian forests could react drastically to even a slight reduction in precipitation".

        I don't find that. The nearest I could find is a quote in the 1994 paper that supports the statement referred to in the head post:

        "A 1994 paper estimated that around half of the Amazonian forests lost large portions of their available soil moisture during drought."

        Yes, forests lose soil moisture during a drought. That is a very different statement from saying that the Amazon could "react drastically to even a slight reduction in precipitation." In fact, the 1994 paper says that in 2001, half of the Amazon suffered a 50% loss in soil water ... but it says nothing about that causing a "drastic reaction". I find nothing in the cited document that makes the 40% claim. This website says that the WWF citation is incorrect, that they really were relying on a 1994 document, Nepstad 1994. It is unknown how this website came to that conclusion ... but the practice of randomly substituting one citation for another hardly inspires confidence. Now, it's possible they were relying on the 1994 document (although we have only this website's word for it). But I find nothing in that document that makes the 40% claim either ... perhaps someone could quote where in the 1994 document the 40% claim was made. Now, I am not saying that the claim is wrong. I do not know whether it is or not. I do think, however, that for the IPCC to rely on a WWF document whose cited reference for a claim does not support what the WWF document says is ... well, it is far away from Pachauri's claim that the IPCC depends 100% on peer reviewed science. This is not even second-hand peer reviewed science, the citation doesn't support the claim. And for this website to say that the WWF document is really referring to a totally different paper (and one which does not contain the 40% claim either) is Monday morning quarterbacking. You present no evidence at all that the WWF was referring to the 1994 paper. Now that you know that the 1994 paper does not contain anything even remotely similar to the claim that "Up to 40% of the Amazonian forests could react drastically to even a slight reduction in precipitation", I suppose that you could come up with some other citation that kinda supports the claim if you squint at it in the right way ... but that's not the point. The point is that the IPCC relied on a WWF paper which was not peer-reviewed, and the citation listed for that WWF claim did not back up the claim ... Finally, you say:

        However, the 40% figure comes from several other papers by the same author that the WWF failed to cite. ... In 2004, new rainfall data showed that half of the forest area of the Amazon Basin had either fallen below, or was very close to, the critical level of soil moisture below which trees begin to die (Nepstad 2004).

        Sorry, not possible. The WWF paper is not dated, but the most recent citation is from 2000, and it refers to 2001 as "the future", viz:

        So when will the next El Niño occur? Scientists at the American Climate Prediction Centre believe that La Niña conditions will prevail globally until March 2000 and it is too early to say when the next El Niño will be. However, the Eighth ASEAN Ministerial meeting on Haze in August concluded that as “La Niña is expected to weaken by the end of this year, meteorological experts have predicted a likely recurrence of dry conditions associated with the El Niño phenomenon next year or by 2001”.

        So unless WWF has invented time travel, the idea that the WWF "failed to cite" a 2004 document is simply not possible ...
116656. Riccardo at 07:58 AM on 27 June 2010
        IPCC were wrong about Amazon rainforests
        For the lazy readers, here's the Global Review of Forrest Fires, Nepstad 2004, Nepstad 2007 and Philips 2009. And should the webmaster at WHRC decide to move their pages again, we won't let them hide anything: Nepstad, D., P. Lefebvre, U. Lopes da Silva, J. Tomasella, P. Schlesinger, L. Solórzano, P. Moutinho, D. Ray, and J. Guerreira Benito. 2004. Amazon drought and its implications for forest flammability and tree growth: a basin-wide analysis. Global Change Biology 10(5):704-717. Nepstad, D.C., I.M. Tohver, D. Ray, P. Moutinho, and G. Cardinot. 2007. Mortality of large trees and lianas following experimental drought in an Amazon Forest. Ecology 88(9):2259-2269. John, you might want to update your link and delete this comment.
116657. gallopingcamel at 07:53 AM on 27 June 2010
        September 2010 Arctic Ice Extent Handicapping Via ARCUS
        CBDunkerson (#54), No big deal. When one is looking at the poles satellite data would be more convincing. Somewhere on another thread it was shown that there are only a handful of high latitude ground stations in the NASA and NOAA data bases. Perhaps you or Berenyi Peter can say how many ground stations there are above 66 degrees latitude. I suspect that the number is too small to justify the fine grained contours seen on NASA anomaly maps.
        Moderator Response: There's no specific thread (yet) for discussion of polar temperature measurement and interpolation so for the time being please continue discussing the polar instrumental temperature record on the Temperature Record Is Unreliable thread. Thanks!
116658. Doug Bostrom at 07:03 AM on 27 June 2010
        IPCC were wrong about Amazon rainforests
        Welcome to Skeptical Science, Willis. Do you have anything more substantial to offer other than pointing out expired links?
116659. Willis Eschenbach at 07:00 AM on 27 June 2010
        IPCC were wrong about Amazon rainforests
        Two of your links go nowhere. The third says nothing about "up to 40% of the Brazilian forest". How is this supposed to convince anyone?
116660. J Bowers at 06:56 AM on 27 June 2010
        How Jo Nova doesn't get past climate change
        To complement this post, I highly recommend Prof. David Greenwood's comment at Climatesight, which is a very lucid description of what we know. http://climatesight.org/the-credibility-spectrum/#comment-2320 Jo Nova should it read it, too, especially as David Greenwood started out as a sceptic.
116661. CBDunkerson at 05:41 AM on 27 June 2010
        September 2010 Arctic Ice Extent Handicapping Via ARCUS
        It's just another aspect of the old 'we cannot predict the weather so we cannot predict climate' fallacy. No, we can't precisely predict the minimum sea ice extent in any given year... but that doesn't change the fact that the long term trend is clearly in sharp decline and we CAN predict eventual complete melt of the Arctic sea ice in Summer. That said, sea ice predictions are constantly improving and have now entered the realm of having some practical usability... specifically they've now got a good enough grasp on some of the dynamics to provide estimates of coastal sea ice stability about a week in advance. This is similar to weather prediction or volcano monitoring... so long as the prediction is limited to situations we have a good handle on they have some viable utility. There is a good article on the subject here.
116662. Peter Hogarth at 05:29 AM on 27 June 2010
        Ocean acidification
        Berényi Péter at 01:56 AM on 27 June, 2010 Being charitable, I see what you have done on your final charts. With hindsight an obvious misunderstanding that should be very quickly clarified here. When we talk about “ocean acidification” we are really talking about pH changes in the upper layers, and not the entire water column. As you have found, deeper waters are much less alkaline anyway (pH around 7.6 at around 700m in this case) and clearly it is the interaction with increasing atmospheric CO2 in the upper layers that is driving the “acidification” process - top down. If you had tracked down and read Dore 2009 (linked above) and looked at figures 1 and 2 you might have saved yourself a bit of aggravation. The variation of pH with depth, and the rate of change of pH with depth, for both the measured and “calculated” values, are shown in figure 2 and it is definitely worth showing on this thread, though I would advise looking at the original, as there is a pleasing level of detail. Hope this is all starting to make sense.
116663. Philippe Chantreau at 04:58 AM on 27 June 2010
        Ocean acidification
        Well it's a good thing that Peter, Riccardo and Doug were here to audit the auditor, isn't it? Let's see what kind of language we find in the "audit": "Outrageous, impermissible, no trend whatsoever." All generously sprinkled with subtle suggestions of incompetence or fraud, based on a superficial and rather incompetent "audit" that the auditor himself now acknowledges as needing to be entirely redone. Perhaps BP should hold on the emotional response, the grandiloquent language and the veiled suggestions of fraud or incompetence until absolute certitude is established that someting is amiss.
116664. dhogaza at 04:57 AM on 27 June 2010
        September 2010 Arctic Ice Extent Handicapping Via ARCUS
        "I have to disagree with this because one thing it does tell us is just how good our understanding of arctic sea ice is. These are the best arctic scientists. Its good to know just how good they are given so much rides on what they are telling us. It's a good complement to peer-review." What they know is arctic sea ice predictions will always be less reliable than long-range weather forecasts, because the variability between years depends so much on weather. If weather forecasters were able to tell arctic sea ice experts what wind patterns (and the partially dependent water circulation patterns), temp anomalies, etc lie in store between now and the third week of September, sea ice forecasting would be far more accurate. But the weather people can't, and therefore sea ice minimum forecasts are guaranteed to be a crapshoot.
116665. Doug Bostrom at 04:38 AM on 27 June 2010
        September 2010 Arctic Ice Extent Handicapping Via ARCUS
        One of the SEARCH predictions might be spot-on this year but that's not going to tell us much about the skill of the method employed. Although we ought to be happy that skills change and improve over time, from another perspective it would indeed be interesting to see the exact methods chosen by each group using a reproducible system applied over several years' time, maybe a decade. Short of that one year is going to teach us very little about the validity of any system of prediction against the other. As Chris suggests this is at the level of a spectator sport for us, or maybe watching tournament poker. It's fun (maybe in a morbid fashion) but shouldn't be taken too seriously. Trends are what we should be paying attention to from a more serious perspective.
116666. chris at 04:22 AM on 27 June 2010
        September 2010 Arctic Ice Extent Handicapping Via ARCUS
        HumanityRules at 03:47 AM on 27 June, 2010 I have to agree with CBW here. We may understand Arctic sea ice quite well, but that doesn't mean that our single year predictions will necessarily be accurate. Predictions should encompass both the essential scientific understanding of sea ice response to warming and its seasonal progression (likely increasingly good) and the inherent uncertainty that results from stochastic variability (aka "weather" in this context). Sea ice response to global warming should increasingly be predictable in relation to the longer term trend that averages stochastic variability. Prediction of yearly levels is fun for the peanut gallery, but doesn't say a huge amount about our understanding of Arctic sea ice unless we (i.e. those that study this) have a good handle on the predictability of weather-related influences. My prediction is lots of blogospheric hot air to come!
116667. HumanityRules at 03:47 AM on 27 June 2010
        September 2010 Arctic Ice Extent Handicapping Via ARCUS
        35 CBW at 01:27 AM on 26 June, 2010 "I find all of these predictions interesting, but not particularly helpful to the discussion of AGW" I have to disagree with this because one thing it does tell us is just how good our understanding of arctic sea ice is. These are the best arctic scientists. Its good to know just how good they are given so much rides on what they are telling us. It's a good complement to peer-review.
116668. HumanityRules at 03:39 AM on 27 June 2010
        September 2010 Arctic Ice Extent Handicapping Via ARCUS
        29 doug_bostrom at 16:19 PM on 25 June, 2010 "Further to HR's thoughts about psychological influences on predictions" No psychological angle from me, are you referring to my use of the word bias? If so what I meant is that the very low 2007 extent is in someway playing through the different methods used to make the prediction. The most likely thing is because so much ice disappeared in 2007 we have very little multi year ice, this effect will continue until next year. I suspect the methods give too much value to this lost ice.
116669. HumanityRules at 03:33 AM on 27 June 2010
        September 2010 Arctic Ice Extent Handicapping Via ARCUS
        25 Neven "I've also written a piece on the Cryosphere Today archive data and the discrepancy with the daily ice concentration map on the front page. No conclusions, unfortunately, but the archive maps look fishy to me." They are not fishy, they just use a different colour scale compared to the images on the front. I don't understand why they don't bother to be consistent.
116670. Doug Bostrom at 02:56 AM on 27 June 2010
        Sea level rise is exaggerated
        Dan, rhetorical laughter is not a persuasive argument. You need to undo some statistics in sufficient detail to show how the measurement uncertainty reported by Donnelly is in error: This 700-year record from Barn Island provides a SLR estimate free of vertical displacement due to autocompaction of the peat column. A linear rate of rise of 1.0 ± 0.2 mm/year intersects all the 2s uncertainty boxes of the record from the 14th to the mid-19th century (Figure 2). Linear regression of the NYC tide-gauge data reveals an average rate of SLR of 2.8 mm/year from 1856–2001 A.D. Why don't you attack the Donnelly paper in detail? Until you do so your credibility does not seem equal to that of the authors you're critiquing.
116671. CBDunkerson at 02:05 AM on 27 June 2010
        September 2010 Arctic Ice Extent Handicapping Via ARCUS
        gallopingcamel, does it matter? Given that the satellite and ground temperature records match other than minor variations, as even the UAH satellite team acknowledges, what's the difference? That said, the anomaly map in question was compiled by NASA from ground station data.
116672. Berényi Péter at 01:56 AM on 27 June 2010
        Ocean acidification
        #60 Peter Hogarth at 10:21 AM on 26 June, 2010 It is a shame you get angry instead of taking time to be more thorough and thoughtful Yes, it is. Let me apologize for that. Fortunately you guys are here to set things straight. What I have actually done is to lump together pH measurements for all sites (there are 24 of them, STNNBR 1-19,50-52,60-61) and all depths (down to 4909.7 dbar, that's about 4821 m). This is what is shown in the graphs above and this is why pH values are so low. Now I see mean surface values are defined as average of measurements taken between 0-30 dbar, that is, the upper 30 m of ocean. As for the sites, Aloha is STNNBR 2. I can see two more, Kahe (1) and Kaena (6). Could not find documentation for the rest. It may be due to the fact neither hot*.sea nor Readme.water.woce referenced in the BEACH Water Column Chemical Data Format Document are to be found at the FTP site. As 87.4% of all measurements were performed at STNNBR 2 (Aloha), depth must be the real problem. At that site only 17.2% of measurements were done "at surface" (down to 30 dbar). With these in mind I will redo my analysis and let you know the results. I assume pH calculations based on other parameters were done by the co2sys. As source code is not available at the CDIAC site, it is a bit cumbersome to perform a proper audit. Documentation of algorithms implemented is also deficient. IMHO no scientific work should be based on closed source applications.
116673. Peter Hogarth at 01:47 AM on 27 June 2010
        Ocean acidification
        Berényi Péter at 04:34 AM on 26 June, 2010 I anticipate that some may argue that the ALOHA data set could be some freak regional anomaly. I mentioned that other oceans and regions are showing similar trends. From NOAA coral reef watch for Greater Caribbean region. Data is surface Aragonite saturation state (used because this is related to coral calcification rates). This is directly proportional to carbonate ion concentration, and hence indirectly to pH. It is up to date and based on ongoing geochemical measurements backed by modeling based on satellite measurements of SST etc. Solid points are confirmed measurements, open points are preliminary. Methodology is described here There are also long time series (25 years) for the high North Atlantic Olafsson 2009 and an admittedly limited number of others. Whilst it is true we do not have a global monitoring network for ocean chemistry yet, we do have enough information from continuous independent measurements from various locations to state that the change in Ocean pH (call it what you will, semantics won’t alter the data) is a reality and is directly caused by the increased atmospheric CO2. We know that this pCO2 increase is a global phenomenon, but is interestingly highest in the North Atlantic. Feely 2010 et al call for a new comprehensive integrated observational network to maintain and increase the reliability and coverage of our data. Take a look at the organizations below the author list. This represents a great deal of collective expertise. To gain further insight into the reality of what we are measuring look at the presentations in pCO2 workshop 2007 These are sobering. Increased pCO2 is evident almost everywhere we look, it tracks the steadily rising atmospheric CO2, mostly just below, meaning on average the Ocean is a sink. For example: Many areas previously identified as CO2 sources are now unambiguously net sinks. Global average pH is steadily decreasing in the upper layers. Some small comfort may be derived from the possibility that reducing Arctic ice cover will allow a significant increase in area of open water that will increase the net CO2 sink.
116674. CBW at 01:37 AM on 27 June 2010
        September 2010 Arctic Ice Extent Handicapping Via ARCUS
        dhogaza: "There are problems with melt ponds on top of the ice fooling the various ice measurement algorithms, but year-to-year comparisons should still be apple-to-apple." This isn't quite true. If surface temperatures are warmer than normal, you could see more melt ponds, which would tend to cause an underestimation of ice area. At the same time, you could have colder sea temperatures keeping the ice from melting through. Given arctic temperatures this year, it's likely that at least the first part of this is happening. If the second part is also happening, we'll likely see a recovery in ice volume (from the straight down trajectory PIOMAS is currently showing), and ice area, once the freezing starts again. But it's unlikely to move the ice volume back to anywhere near the 1979-2009 trend line. That looks broken for good. In any event, the existence of abnormally extensive melt ponds is in itself an important observation. Either way, things are warming up in the arctic.
116675. dhogaza at 23:59 PM on 26 June 2010
        September 2010 Arctic Ice Extent Handicapping Via ARCUS
        a_yeeles "Precisely. Which is why, as AMSU-A shows global temperatures continuing to track well above average, an exceptional arctic ice season may well be in prospect." People talk about weather patterns and melt because water is a much more effective melter of sea ice than warm air. The warmer temps are going to accelerate melting, of course, but for a truly exciting melt season we need more than that. We need ice being pushed down from the arctic basin into the (relatively) balmy narrows of the Nares Strait, or the ocean south of the Fram Strait. At least, that's what the 2007 season told us. If it stays super-warm up there over the next three months, as it is currently doing, maybe that will have a bigger effect on extent and area of coverage and the movement of ice into warmer waters won't be so important. Each day that passes leads me to believe we might, as you say, have a very low minimum extent. The next four weeks will tell us a lot.
116676. gallopingcamel at 23:30 PM on 26 June 2010
        September 2010 Arctic Ice Extent Handicapping Via ARCUS
        CBDunkerson (#46), Is that temperature anomaly map based on satellite or ground station data?
116677. daniel at 22:03 PM on 26 June 2010
        Sea level rise is exaggerated
        To doug-bostrom post # 19 Sorry it has taken me a month to get back to you doug. You're links were a little hard to follow to be honest and I will say that it is probably because they are lengthy wafflings about how we can test the outputs of a simple two term equation to a "simulated" millenial scale model and recent sea level observations. We all know that water expands when heated and although there may be some credibility issues with the global temperature record of the last 200 years we can safely assume that things have warmed a bit since the LIA and that the sea level may have responded. The question is, just like the temp record, is it unprecedented? Rather then spend time reading how the two term equation predicts future sea levels I decided to turn my attention instead to the papers cited by the above article. The article claims that skeptics are guilty of interpreting small recent trends from noisy data as significant. Here's a quote: "The lesson from this is to treat with skepticism anyone who concludes long term trends from several years of a noisy signal (after all, skepticism should cut both ways)" Yes indeed it does cut both ways. What the author of this article doesn't realise is that the two papers cited for paleo sea levels make the mistake of claiming an unprecedented rapid sea level rise from very noisy data. The Donnely paper, on the reconstruction of SLR at Barn Island Connecticut, on it's own is simply an utter joke. 10 or so paleo samples with quite large height and age uncertainties are used to construct a linear 1mm/year sea level trend over 1300-1850 A.D. There is more than enough slack in this data to periodically reproduce the apparently rapid sea level rise of 2.8mm/year in the NYC tide gauge data of the last ~150 years (cited and compared to by the authors). The Gehrels paper I would say is a much more commendable attempt at reconstructing sea levels off the west Icelandic coast. The low resolution issue is adressed but the uncertainty issue does not disappear. Height and age error estimates again provide more than enough slack to allow the reproducuction of the modern rates of sea level rise. The authors fail to discuss the suspicious nature of the sudden and relatively linear increase in sea level reconstruction at ~ 1800 A.D. which also marks the point at which the age of the reconstruction is measured by Pb and Cs isotopic ratios and paleo-magnetism rather than the seemingly much less certain C14 analysis. As I have mentioned elsewhere on this website (see "There is no concensus" argument page) the claim that "experts" of climate science have a more credible opinion on this issue is highly insulting to scientists from other fields. Scientists who after having found the time and inclination to review the data of climate scientists are utterly apalled at the conclusions drawn.
116678. a_yeeles at 19:09 PM on 26 June 2010
        September 2010 Arctic Ice Extent Handicapping Via ARCUS
        Oops, sorry Link should be http://discover.itsc.uah.edu/amsutemps/ Apologies
116679. a_yeeles at 19:06 PM on 26 June 2010
        September 2010 Arctic Ice Extent Handicapping Via ARCUS
        CBDunkerson #46 "Actually, temperatures in the Arctic have been further above normal than any other part of the world." Precisely. Which is why, as AMSU-A shows global temperatures continuing to track well above average, an exceptional arctic ice season may well be in prospect. ( http://discover.itsc.uah.edu/amsutemps/execute.csh?amsutemps )
116680. Pete Dunkelberg at 11:18 AM on 26 June 2010
        September 2010 Arctic Ice Extent Handicapping Via ARCUS
        "... or if the reports of rotten older ice last year turn out to be important." As a_yeeles says, the heat is important. BTW, watch for new information Tuesday.
116681. Peter Hogarth at 10:21 AM on 26 June 2010
        Ocean acidification
        Thanks Doug, Riccardo, Berényi Péter at 04:34 AM on 26 June, 2010 It is a shame you get angry instead of taking time to be more thorough and thoughtful. I have always tried to treat your responses and somewhat tangential offerings in a gracious manner. In response to your unnecessary detective trail, allow me to clarify. The image I presented was one of many from sources around the world I could have chosen, but it had the merit of being clear and uncluttered. Here is one from Doney 2010 (which I think you should purchase and read) using updated data, and the image is adapted from Dore 2009 which is free, but which you should also read in full. You question the colour coding of the data presented in my first image. Well here is the correct explanation (from the Doney 2010) image which is at odds with your assumed one. All values are measurement based. You are wrong to simply assume otherwise based on some bias you seem to have, or some quick internet search. Red symbols are partial pressure of CO2 in seawater calculated from measured DIC (dissolved inorganic carbon) and TA (total alkalinity). Green symbols are direct measurements of pH in water-saturated air at in situ seawater temperature. Further let me quote from Doney 2010 as you have previously seen fit to reproduce an image from Doney 2006 to support your argument: “The rates of change in global ocean pH and are unprecedented, a factor of 30 to 100 times faster than temporal changes in the recent geological past, and the perturbations will last many centuries to millennia. The geological record does contain past ocean acidification events, the most recent associated with the Paleocene-Eocene Thermal Maximum 55.8 million years ago. But these events may have occurred gradually enough and under different enough background conditions for ocean chemistry and biology that there is no good paleo-analog for the current situation” Perhaps you should consider my calm measured interpretation of what the experts and Oceanographers around the world are saying, and apologise.
116682. michael sweet at 10:00 AM on 26 June 2010
        September 2010 Arctic Ice Extent Handicapping Via ARCUS
        Several of the SEARCH predictions mentioned the amount of second and third year ice present north of Alaska. The first year ice there has mostly melted out now. In the next few weeks we will see if the older ice holds out against melt, or if the reports of rotten older ice last year turn out to be important. The sea ice melt is such a fast event for global climate that is is easy to watch closely.
116683. CBDunkerson at 09:18 AM on 26 June 2010
        September 2010 Arctic Ice Extent Handicapping Via ARCUS
        a_yeeles #45: "...or are arctic weather patterns immune to what's happening in the rest of the world?" Actually, temperatures in the Arctic have been further above normal than any other part of the world. The map below shows anomalies for May, with red being warmer than normal and blue being cooler;
116684. chris at 09:16 AM on 26 June 2010
        Robust warming of the global upper ocean
        Ken Lambert at 23:26 PM on 10 June, 2010 You persist in pursuing an illogic argument Ken. If you argument is to have any merit you should produce some evidence that the geothermal heat flux has miraculously accelerated hugely (i.e. doubled) during the last couple of decades during which we've seen an apparent large increase in deep ocean heat. This has been explained in response to your previous pursuit of this odd argument here, and here.
116685. chris at 08:41 AM on 26 June 2010
        Astronomical cycles
        Ken Lambert at 23:44 PM on 21 June, 2010 I know I shouldn't be talking about ocean heat, but I can't let a couple of your comments go unremarked: "Chris and I have debated the TOPEX - Jason satellite transition - and if the two trends are linearized - there is a flattening in the Jason record closer to 2.0mm than 3.2mm per annum often quoted over the combined record. There is also the probably of an offset error in the transition." That's incorrect on two counts Ken. (i) There is no contemporary "flattening" of the Jason sea level record. There was a temporary apparent slow down in the rate of sea level rise during the period around 2006-2008. That may or may not have been real (if so it's quite interesting, yes?). However if you are going to assert that that slow down is of significance (it may well be), then you really should take on board the fact that during the 2.4 year period from 2008 until the present, the Jason sea level rise regresses to a value of 6.5 mm.yr-1; a massive acceleration. More realistically, the sea level rise continues around the trend of the last 17 years near 3.2 mm.yr-1 (it may be accelerating; time will tell). That is simply incompatible with the absence of ocean heat uptake that you are attempting to deduce. (ii) Your insinuation of a "probably of an offset error in the transition" is completely unsubstantiated. We saw in a previous discussion how this was unlikely to be the case. You can't just assert "offset errors" willy-nilly to support a particular viewpoint.
116686. a_yeeles at 08:39 AM on 26 June 2010
        September 2010 Arctic Ice Extent Handicapping Via ARCUS
        As an (ex) biologist who's followed the arctic ice situation with interest for a couple of years I'm somewhat perplexed that while a number of comments have emphasised the crucial importance of weather patterns in determining the eventual ice melt this year (eg #25 Neven "Of course it's all down to weather...."), no-one has mentioned that globally the first months of this year have been the warmest on record, or that record high temperatures have been recorded in country after country recently. It would surely be paradoxical if the increased heat energy in the earth's system does not have at least a modicum of influence on arctic weather over the next couple of months, and thus on the eventual ice minimum. For example, Weather Canada is predicting that Resolute, Cormwallis Island, will experience *night* temperatures in excess of the average daytime values for an extended period this week as a result of hot air being dragged up from far down in the US Great Plains. Is this common (I don't recall this happening last year) or are arctic weather patterns immune to what's happening in the rest of the world?
116687. tobyjoyce at 07:31 AM on 26 June 2010
        September 2010 Arctic Ice Extent Handicapping Via ARCUS
        The "tape" graphic from Cryosphere is significant, IMO. This year is the first year there has been such a precipitious drop this time of year. As Neven pointed out, the June daily melt rate has been the highest on record and the melt season is only beginning. The chart is the NH Sea Ice Anomaly, the sentre line is the 179-2008 mean.
116688. dhogaza at 07:18 AM on 26 June 2010
        September 2010 Arctic Ice Extent Handicapping Via ARCUS
        BP:

        It is not proper to use it to study year to year changes. PIPS, is known to be not terribly useful for sea ice other than perhaps motion; definitely not thickness.

        I'm curious as to what about this statement is so difficult to understand.
116689. CBDunkerson at 06:53 AM on 26 June 2010
        September 2010 Arctic Ice Extent Handicapping Via ARCUS
        BP #41, how are you defining 'worse'? The 2010 June extent is the lowest of the bunch... and in that sense it is "worse" than ALL of them. Presumably you're still concentrating on the green/yellow/red mass in the Arctic basin... but that doesn't look any larger than it was at this point in 2007 (though the shape is different). It is also CLEARLY much smaller than it was in 2002-2005, especially 2004. All these predictions are, of course, contingent upon the weather. In truth anything between 3 and 6 could happen depending on what the weather does. However, we are currently at both the lowest extent and fastest rate of decline on record for this time of year. That perforce means that unless conditions change significantly we're looking at a low extent this year.
116690. Berényi Péter at 06:28 AM on 26 June 2010
        September 2010 Arctic Ice Extent Handicapping Via ARCUS
        

        	I've put 21 June 2002-2009 PIPS2 images along with smallest extent for each year. Plus 21 June, this year. It does not look worse than any one of them, except the stripe of old extremely thick ice on the western side is gone.

116691. Doug Bostrom at 06:27 AM on 26 June 2010
        Ocean acidification
        BP, a suggestion. Rather than become angry, why not follow step-by-step the methods used by HOT and identify where you think they run off the rails, where their method is specifically defective? The graphs you're displaying create a strong impression but your argument boils down to There is no way one can get the red line from these raw pH data. This is remindful of the ocean heat matter. You say it's wrong, but you can't say how, exactly. Just so we're on the same page, here's the method as reported by HOT: Feb 17, 2009 - All HOT pH data presently available through HOT-DOGS were collected using the spectrophotometric method of Clayton and Byrne (1993) and are reported at a constant temperature of 25°C. The +0.0047 unit correction suggested by DelValls and Dickson (1998) has NOT been applied to any HOT data. The 1992-1993 HOT pH data were originally reported on the Seawater Scale, while later data have all been reported on the Total Scale. For the sake of consistency, the 1992-1993 pH data have as of today been converted to the Total Scale according to Lewis and Wallace (1998). The Total Scale values are approximately 0.01 pH units higher than the Seawater Scale values they replace. The cruises affected are HOT 36-47 and HOT 49-50. Prior to 1992, on HOT 23-32, pH measurements were made using a pH electrode calibrated with NBS buffers and were reported on the NBS Scale. Potentiometric measurements of pH are inherently less precise than spectrophotometric measurements. Moreover, the relationship between the NBS Scale and the Total Scale is not exact and depends on characteristics of the electrode employed. Given these difficulties, we have not attempted to correct the pre-1992 data to the Total Scale. They are available in the raw data files via FTP and remain as reported on the NBS Scale, but have been assigned a questionable quality flag and thus are not accessible through HOT-DOGS. References: Clayton, T.D., and R.H. Byrne. 1993. Spectrophotometric seawater pH measurements: total hydrogen ion concentration scale calibration of m-cresol purple and at-sea results. Deep-Sea Res. I 40: 2115-2129. ; DelValls, T.A., and A.G. Dickson. 1998. The pH of buffers based on 2-amino-2-hydroxymethyl-1,3-propanediol (tris) in synthetic seawater. Deep-Sea Res. I 45: 1541-1554. ; Lewis, E., and D.W.R. Wallace. 1998. Program Developed for CO2 System Calculations. ORNL/CDIAC-105. Carbon Dioxide Information Analysis Center, Oak Ridge National Laboratory, U.S. Department of Energy, Oak Ridge, Tennessee.
116692. Riccardo at 05:49 AM on 26 June 2010
        Ocean acidification
        Berényi Péter, if the data you found over the internet do not match what's published you have two possibilities: 1) assume you're doing something wrong or misunderstanding something and eventually ask to the people responsible for the data; 2) assume you're right, get angry at the scientists and join the "it's a conspiracy" crew. You choice. The rest of the readers might want to take a look at the "official" data.
116693. Gneiss at 05:22 AM on 26 June 2010
        September 2010 Arctic Ice Extent Handicapping Via ARCUS
        Quite a fracture developing upstream from Nares Strait, between apparently shorefast ice attached to N Greenland, and a soup of floes that looks like it all wants to float south. Looking at past years' NSIDC minimum maps, I didn't see open water in this area. Have features like this long fracture been common, or is it something new?
116694. VoxRat at 05:16 AM on 26 June 2010
        Ocean acidification
        GeoGuy #55 "From what I've found out only 15% is converted, the balance being held in a "molecular trap" of water molecules." But it turns out you're wrong about that. Where did you get this (mis)information?
116695. Berényi Péter at 04:34 AM on 26 June 2010
        Ocean acidification
        #44 Peter Hogarth at 20:54 PM on 25 June, 2010 overarching concerns on anthropogenic CO2 (specifically) and reduced alkalinity of the Oceans can be summarized in the following images And you show us this picture: The original one in Feely, et al. PICES Press 16(1), 22-26 (2008) looked like this: Caption: Atmospheric carbon dioxide from Mauna Loa (ppmv) and pCO₂ (μatm), and surface ocean pH time series data from Ocean Station Aloha So pCO₂ and pH are not from "North Pacific Ocean" in general, but specifically from monthly cruises to the deep-water Station ALOHA (A Long-Term Oligotrophic Habitat Assessment; 22° 45'N, 158° 00'W) as part of the Hawaii Ocean Time-series (HOT). You can have a look at ocean pH at the HOT site by choosing "pH Comparison". It is the pH data trend as derived by the HOT sampling program and looks like this: It is not exactly the graph shown by Feely in light blue, but looks similar. Alas, it is not all actual data, but some measurement (red) overlaid on something calculated by the HOT sampling program in an unspecified way (blue). Values actually measured, then adjusted by HOT look like this: Not quite the trend above, but still. Fortunately HOT also has an ftp site with all the raw data from 206 cruises. ftp://ftp.soest.hawaii.edu/dkarl/hot/water/ If one takes pH measurements from there, gets something like this: Now that's outrageous. There is no way one can get the red line from these raw pH data. The first run, before 2000 is obviously unusable. It is pure junk. But let's have a closer look at the latter part, between 2003 and 2008. N O   T R E N D  whatsoever. Data enhancement like this in any other branch of natural sciences would be considered impermissible. However, it is standard practice in mainstream climate science (sorry, but I am getting angry).
116696. Geo Guy at 04:07 AM on 26 June 2010
        Ocean acidification
        VoxRat # 32 - The issue deals with how much of the CO2 that is taken up by the ocean does in fact convert to carbonic acid. From what I've found out only 15% is converted, the balance being held in a "molecular trap" of water molecules. Hence the basis of my post is that not all of the CO2 going into the ocean is converted to carbonic acid and once you've factored that in, the role of SO2 in acidification becomes much more evident...nuff said.
116697. Pete Dunkelberg at 04:05 AM on 26 June 2010
        September 2010 Arctic Ice Extent Handicapping Via ARCUS
        I predict a record low. Note how the ice is declining while the temperature is "inclining". Why should either of these things change much by September? Of course the current fast melt will run into some thicker ice. The winds associated with the very negative Arctic Oscillation reduced ice export through the Fram Strait last winter and caused a relative buildup of thicker ice. The same winds and surface driven currents kept the Arctic warmer than usual last winter. Watch the ice melt. dhogaza: "It's going to be a good summer to watch ice." I totally agree.
116698. Albatross at 04:05 AM on 26 June 2010
        How many climate scientists are climate skeptics?
        ChrisG @124, "It appears to me that, about 100 years ago, AGW proponents were the voice in the wilderness. Over time, and much research, their position has grown in strength." You make an outstanding observation Chris! Have you read Weart's book "The discovery of global warming"? Probably. In 1910, scientists thought Arrhenius was out to lunch. Specifically, skeptics thought that the saturation effect was problematic to his thesis. The skeptics' argument "the CO2 effect is saturated" was raised 100 years ago, and over time science and observations have since dismissed that concern. Yet to this day, that argument is still being made by "skeptics". Callander faced a skeptical and dubious audience when he made his presentation to the Royal Met. Soc. in 1938. Back then (in the late thirties) and to quote Weart "The idea that humans were influencing global climate by emitting CO2 sat on the shelf with other bric-a-brac, a theory more peculiar and unattractive than most". Astounding to think that after all our collective advances in the science and knowledge, and multiple, independent lines of evidence supporting the theory of AGW, that to this day there still remain intelligent and well-educated people who remain highly skeptical and who still hold opinions geld back in the early 20th century. So a fully concur when you say "In that light, the anti-AGW proponents are more like the last holdouts rather than leading edge drivers of a new paradigm."
116699. michael sweet at 03:24 AM on 26 June 2010
        September 2010 Arctic Ice Extent Handicapping Via ARCUS
        The daily images at Cryosphere Today come from the University of Bremen and are AMSR-E images. The comparison images look like the daily images at NSIDC, which are DSMP SSSM/I images. The AMSR-E images are supposed to be more accurate, but they often show melt ponds as open water. The cutoff for ice free is also different in the two images. If you compare the two they do not look the same on a single day. On the other hand, the comparison ap on Cryosphere Today shows two images from the same sensor so they are useful for comparing two different dates. It often does not work to compare two ice images from different sources. BP: I copied this letter from Goddard's blog at WUWT. Someone wrote the NSIDC and asked about PIPS data. As you can see, Dr. Meier thinks that you cannot use the PIPS data to determine ice volume as you have done. He says both the thickness and concentration are known to be inaccurate. PIPS data is not intended to be used to determine volume-- the scientists at PIPS do not make a claim of ice volume. WUWT likes to use this data because it seems to conform to their agenda, even though it is known to be inaccurate. On the other hand, PIOMAS data is intended to measure ice volume, and PIOMAS is at a record low. “Thank you for contacting NSIDC. Walt Meier, one of our sea ice scientists provided some thoughts which I will sum up along with a few other points from talking with other scientists here at NSIDC: Unfortunately, there are no continuous, Arctic-wide measurements of sea ice volume/thickness which is why models are used to estimate volume/thickness. Sea ice extent on the other hand is derived from remotely sensed data from satellites. The PIPS model is an operational model, and is designed to forecast the ice a few days into the future (for navy submarine use, etc). It is not proper to use it to study year to year changes. PIPS, is known to be not terribly useful for sea ice other than perhaps motion; definitely not thickness. Our assessment at ( http://nsidc.org/arcticseaicenews/) is based on (1) the ice age fields we get from data from our colleagues, Charles Fowler and James Maslanik, Colorado Center for Astrodynamics Research, University of Colorado Boulder, (2) models better suited to tracking thickness year to year, such as the University of Washington, PIOMAS model we’ve discussed in the past couple articles, and (3) consultation with operational ice centers that have very high quality data and human expertise at assessing the state of the sea ice. The PIOMAS model is looking back in time and estimating what the volume was in order to monitor trends. It has the benefit of “hindsight” and can incorporate actual recorded measurements (weather, satellite data etc.) that by nature are not available to make a forecasts. The most recent update of the PIOMAS model looks to be May 30th. Let me know if you have any more questions or need more information. Regards, Kara Gergely NSIDC User Services” here is the original blog post http://www.climat-evolution.com/article-banquise-arctique-pips-piomas-52419993.html
116700. Chris G at 02:23 AM on 26 June 2010
        How many climate scientists are climate skeptics?
        It's unfortunate, but we are in a situation where a judgment has to be made, because withholding a decision is the same as deciding to do nothing, and made by those who really aren't capable of understanding the deeper technical aspects of the science. It's rather like a jury faced with rather technical forensic evidence. They have only the judgements of the experts to base their decision upon. I think that is why there is as much interest in the consensus argument as there is.

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