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Comments 116451 to 116500:
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Doug Bostrom at 02:56 AM on 27 June 2010Sea 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. -
CBDunkerson at 02:05 AM on 27 June 2010September 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. -
Berényi Péter at 01:56 AM on 27 June 2010Ocean 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.
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Peter Hogarth at 01:47 AM on 27 June 2010Ocean 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.
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CBW at 01:37 AM on 27 June 2010September 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. -
dhogaza at 23:59 PM on 26 June 2010September 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. -
gallopingcamel at 23:30 PM on 26 June 2010September 2010 Arctic Ice Extent Handicapping Via ARCUS
CBDunkerson (#46), Is that temperature anomaly map based on satellite or ground station data? -
daniel at 22:03 PM on 26 June 2010Sea 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. -
a_yeeles at 19:09 PM on 26 June 2010September 2010 Arctic Ice Extent Handicapping Via ARCUS
Oops, sorry Link should be http://discover.itsc.uah.edu/amsutemps/ Apologies -
a_yeeles at 19:06 PM on 26 June 2010September 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 ) -
Pete Dunkelberg at 11:18 AM on 26 June 2010September 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. -
Peter Hogarth at 10:21 AM on 26 June 2010Ocean 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.
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michael sweet at 10:00 AM on 26 June 2010September 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. -
CBDunkerson at 09:18 AM on 26 June 2010September 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; -
chris at 09:16 AM on 26 June 2010Robust 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. -
chris at 08:41 AM on 26 June 2010Astronomical 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. -
a_yeeles at 08:39 AM on 26 June 2010September 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? -
tobyjoyce at 07:31 AM on 26 June 2010September 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. -
dhogaza at 07:18 AM on 26 June 2010September 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. -
CBDunkerson at 06:53 AM on 26 June 2010September 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. -
Berényi Péter at 06:28 AM on 26 June 2010September 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. -
Doug Bostrom at 06:27 AM on 26 June 2010Ocean 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. -
Riccardo at 05:49 AM on 26 June 2010Ocean 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. -
Gneiss at 05:22 AM on 26 June 2010September 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? -
VoxRat at 05:16 AM on 26 June 2010Ocean 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? -
Berényi Péter at 04:34 AM on 26 June 2010Ocean 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).
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Geo Guy at 04:07 AM on 26 June 2010Ocean 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. -
Pete Dunkelberg at 04:05 AM on 26 June 2010September 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. -
Albatross at 04:05 AM on 26 June 2010How 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." -
michael sweet at 03:24 AM on 26 June 2010September 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 -
Chris G at 02:23 AM on 26 June 2010How 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. -
Doug Bostrom at 02:20 AM on 26 June 2010Ocean acidification
Stop whining about C02 Is it an insurmountable intellectual challenge to realize that we're capable of causing more than one problem simultaneously and that different problems may act on different time scales? Please, you can do better. -
dhogaza at 02:19 AM on 26 June 2010September 2010 Arctic Ice Extent Handicapping Via ARCUS
"Currently the arctic is (and has been for a month) at its record low in extent. If going toward the pole the ice is thicker than that found last summer it may slow down a bit. But if the increased thickness is due to ridging it may not happen, it cracks and melts more easily." The thing I find interesting is that the cryosphere ice area calculation is dropping like a rock. It took a real step turn downwards a couple of weeks ago, while the extent estimates continue on roughly a linear pace. 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. So it appears that not only is extent dropping rapidly, but there's more open water within the extent area compared to the last couple of years, due to recent acceleration of the decrease in area mentioned above. I still think 2008 < 2010 < 2009 but am prepared to be surprised on the low end. It's going to be a good summer to watch ice. -
Chris G at 02:10 AM on 26 June 2010How many climate scientists are climate skeptics?
I would have been interested in seeing the charts above with an added dimension of time. The reason I say that is because I get the impression that the deniers believe that the anti-AGW researchers are like a voice in the wilderness that will eventually be proven correct. 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. In that light, the anti-AGW proponents are more like the last holdouts rather than leading edge drivers of a new paradigm. -
Philippe Chantreau at 02:01 AM on 26 June 2010How Jo Nova doesn't get the CO2 lag
Arkadiusz, is there such a thing as "official scientific reviewer" in IPCC terminology? I remember the term "expert reviewer", a status in fact so open that it does not mean much. Are you talking about the same thing? We already had that conversation about Dip Phil Courtney, who is just a PR guy by trade. Full information indeed is necessary, as in the Maxwell Bay sediment core story. The expert review invitation thingy was discussed long ago here: http://rabett.blogspot.com/2008/02/on-astounding-diplphil-courtney.html -
Riccardo at 01:42 AM on 26 June 2010September 2010 Arctic Ice Extent Handicapping Via ARCUS
There will always be more multi-year ice when last summer did not melt as much as the second last. This is trivial. To have volume you have to combine thickness and ice extent or area. Trivial, again. Currently the arctic is (and has been for a month) at its record low in extent. If going toward the pole the ice is thicker than that found last summer it may slow down a bit. But if the increased thickness is due to ridging it may not happen, it cracks and melts more easily. I will not bet on next september minimum, too complicated to put a reasoned one. Considering the standard deviation of 0.5 MKm2 calculated from NSIDC data, I don't see much of a difference between the various estimates. But one thing seems likely, the lack of recovery after 2007 (as a trend, not a few years) will be confirmed. -
Philippe Chantreau at 01:32 AM on 26 June 2010How many climate scientists are climate skeptics?
This is so funny. On one hand we have Watts and Goddard doing grotesquely inept maths with percentages so that they can claim "Western snow pack is 137% of normal." And the Hoi Polloi crowd goes wild: "I've had so much snow this winter." Skepticism nowhere to be found. On the other hand we have the Anderegg survey and statements like this in Slate: "perception that climate activists will credulously push any news that might further their case." The double standard has gone so far, it's downright ludicrous. But no "skeptic" protest is to be heard. Skeptics by name only, a name they actively empty of all the substance it used to have. -
CBW at 01:27 AM on 26 June 2010September 2010 Arctic Ice Extent Handicapping Via ARCUS
HR: "I also predict that PIOMAS will underestimate again this year." Note that the Zhang prediction isn't entirely based on PIOMAS. Here is a link to the prediction page: http://psc.apl.washington.edu/zhang/IDAO/seasonal_outlook.html Also, Ron Lindsay (also at PSC) has his own prediction method: http://psc.apl.washington.edu/lindsay/September_ice_extent.html I find all of these predictions interesting, but not particularly helpful to the discussion of AGW because they distract from the data. The long-term trend is what is important. The predictions, while they serve a useful purpose for regional economic and environmental activities, give critics ammunition when they are wrong, as they often will be in an area with weather systems that are as variable as those of the arctic. The data alone make the case well enough. The long-term trends of arctic sea ice extent, area, and volume are downward, and that is very strong evidence of a warming arctic climate. -
Philippe Chantreau at 01:15 AM on 26 June 2010September 2010 Arctic Ice Extent Handicapping Via ARCUS
I wouldn't venture to any prognostic myself. Arctic sea ice is very weather dependent from year to year. Right now it is rather low and the decline since the max extent has been quite steep. But the summer decline is dependent on wind patterns perhaps more than anything else. If winds do not disperse the ice, it won't be carried away and melt. Prognostic is much of a gamble. All we can do is wait and see -
snapple at 01:15 AM on 26 June 2010September 2010 Arctic Ice Extent Handicapping Via ARCUS
Some of those denialists spin more than a baby seal being tossed by an orca! http://legendofpineridge.blogspot.com/2010/06/george-monbiot-attacks-delingpole-spins.html -
dhogaza at 01:09 AM on 26 June 2010September 2010 Arctic Ice Extent Handicapping Via ARCUS
"Given that the ice sheet extent is on track to dip below the record low Sept/Oct 2007 levels that caused panic at the IPCC, you folks are showing admirable restraint. Nobody is going ape s**t." IPCC suggests that the arctic will become ice free in summers in the 2050-2100 time frame, hardly panic. If you want panic, note that those noted warmists Watts and Goddard recently predicted an ice free arctic by 2060. Much more pessimistic than the IPCC! Of course there's been a flurry of posts afterwards trying to live that down, since they were apparently under the misapprehension that the consensus date for an ice free arctic is 2013... -
Peter Hogarth at 23:28 PM on 25 June 2010Is the long-term trend in CO2 caused by warming of the oceans?
Lon Hocker at 17:37 PM on 24 June, 2010 Thank you for commenting here, and the effort at reasoned discussion. I’m late to this conversation, and just posted these images on another thread on “acidification”. They are pertinent to this one also, so I hope all will forgive the repetition.This image is from here which shows gridded annual average air/sea carbon flux. By measurement and best estimates the ocean is a net CO2 sink and is changing pH most rapidly in areas of highest uptake. If we accept what NOAA and other Oceanographic Institutes etc are telling us, then your premise is suspect without invoking any maths. How can you account for a trend of more measured CO2 in the ocean over time (and with overall warming in the same period), rather than less? The ocean is absorbing a large proportion of the extra emitted anthropogenic CO2, which also explains the difference between increasing measured atmospheric concentration and estimated anthropogenic output, ie the extra emissions not residing in the atmosphere are going somewhere (split between Ocean and other sinks such as increased vegetative biomass in NH). These strands of evidence are consistent.
From R. Feely, Pacific Marine Environmental Laboratory, NOAA, with atmospheric data from Pieter Tans and seawater data from David Karl. Adapted from Feely (2008) in Levinson and Lawrimore (eds), Bull. Am. Meteorol. Soc, 89(7): S58. Enough instrumental evidence has now accumulated so that this trend in overall pCO2 increase and reduction in alkalinity is now accepted as measured fact rather than possible emerging trend, model or theory. As such, your proposed mechanism needs revision. However the correlation between temperature and CO2 derivatives is interesting, and would go some way to explain the variations superimposed on the rising trend. To counter this however, I would suggest you check Southern Hemisphere CO2 seasonal variations (relatively much more Ocean), which are considerably less than NH variations (relatively more land). Just a thought.
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VoxRat at 23:17 PM on 25 June 2010Ocean acidification
"THESE WARM SEA’S CHARACTERIZED MOST DIVERSE AND VARIED LIFE IN OCEANS AS WE KNOW." I don't think anyone is suggesting that dropping the pH a few tenths of a point - even a full point or two - or raising the temperature a degree or two or five is incompatible with life, which seems to be the strawman argument you're addressing. Try this thought experiment: change the temperature in the Red Sea to that of the mid-Pacific. What happens to the that "MOST DIVERSE AND VARIED LIFE"? Now change the pH to that of the mid-Pacific. What happens? Now, change both of them, and not over the tens or hundreds of thousands of years that (I'm guessing) the Red Sea biome had to adapt to the current conditions, but in the course of a century or two. What happens? -
Arkadiusz Semczyszak at 23:16 PM on 25 June 2010Ocean acidification
“A team of scientists from the New York-based Wildlife Conservation Society (WCS) has reported a rapid recovery of coral reefs in areas of Indonesia, following the tsunami that devastated coastal regions throughout the Indian Ocean four years ago today. The team, which has surveyed the region's coral reefs since the December 26, 2004 tsunami, looked at 60 sites along 800 kilometers (497 miles) of coastline in Aceh, Indonesia. The researchers attribute the recovery to natural colonization by resilient coral species, along with the reduction of destructive fishing practices by local communities. While initial surveys immediately following the tsunami showed patchy (albeit devastating) damage to coral reefs in the region, surveys in 2005 indicated that many of the dead reefs in the study area had actually succumbed long ago to destructive fishing practices such as the use of dynamite and cyanide to catch fish. [...] It is also possible that the crown of thorns starfish—a marine predator—had caused widespread coral mortality.” -
Arkadiusz Semczyszak at 22:41 PM on 25 June 2010Ocean acidification
Arabian Sea - with a pH of one of the lowest in the world (less than 7.95) ... In my youth, the first textbook about the life of the sea was, of course, "Sea Life" (Demel, 1974) Professor Demel, the eminent scientist (already dead), a member of many international scientific societies ... Recently, after many years, I found this book. Today I found there the following passages: "The Red Sea is a sea of the world's hottest maximum temperature in summer on the surface to 30oC, with "slots" extremely hot waters with temperatures exceeding 50 ° C and at depths to 2000 meters, not falling below 21.5 ° C ...", they has: "many strange sponge and very rich [...] coral reefs." and: "Persian Gulf, plate, lying on the shelf, the highest in the sea water temperature (up to 36 deg. C) is a place in the richest fishing mollusc (Pteriidae) of global world... " Professor ends like this: "THESE WARM SEA’S CHARACTERIZED MOST DIVERSE AND VARIED LIFE IN OCEANS AS WE KNOW." -
CBDunkerson at 21:35 PM on 25 June 2010Is the long-term trend in CO2 caused by warming of the oceans?
Lon Hocker #116: "CBDunkerson: Thank you for your strangely illogical comment. I found it amusing. As with e, I see little hope in helping you. Doug: Stop picking on e and CBDunkerson!" Ah. Trolling. Ok, you've officially passed the point of being worth bothering with. -
CBDunkerson at 21:27 PM on 25 June 2010September 2010 Arctic Ice Extent Handicapping Via ARCUS
BP #14/30, why would the yellow spot forming in the Beaufort be indicative of HIGH extent this year? Essentially what is happening is that a large area of thinner ice is being compressed into a smaller area of thicker ice by the gyre. Given that extent is 'ice area / concentration' wouldn't decreasing area and increasing concentration serve to yield a LOWER extent? That said, I expect the yellow swathe will break up as the season continues. That's the kind of pressed together 'rotten ice' they've been finding which doesn't really have much solidity to it. As to the general premise of the arctic basin ice being thicker this year than last - there has been alot of dispute about that with different methodologies coming up with different thickness measurements. However, I don't think it is as significant as you suggest... from the rate of decrease on the map it seems very likely that all the ice now at 2.5 meters in thickness or less is going to melt (indeed by the end of the animation the only such ice left is a small band that previously was 3+ meters thick). If you then look at the 3+ meter ice on the last frame of that 2010 map you'll see that it covers roughly a triangular shape "anchored across the northern edge of Greenland and Ellsmere Island and stretching northwards towards Severnaya Zemlya"... in other words, precisely the section I predicted would NOT melt this year. So yes, there is a core of potentially thicker / more solid ice (though some studies seem to indicate it is thinner/weaker than aerial observations suggest) in the Arctic basin this year. But if that is all which survives the melt, as seems very likely, then we're still looking at a very low extent this year. -
chris at 21:18 PM on 25 June 2010Ocean acidification
Berényi Péter at 21:07 PM on 25 June, 2010 Peter, you really need to read the Manzello paper whose abstract you linked to. The very fact that upwelling waters are [CO2] rich and thus relatively acidic means that coral reefs struggle in regions of upwelling. Manzello states this explicitly. In fact it's much of the point of his study, namely that as ocean acidification becomes widespread the degradative effects on coral reefs he observes in the eastern Pacific and around the Galapagos, will occur throughout the oceans. I just described this here with an excerpt from the Manzello paper -
Berényi Péter at 21:07 PM on 25 June 2010Ocean acidification
#38 Peter Hogarth at 18:32 PM on 25 June, 2010 "These naturally high-CO2 reefs persist near the Ωarag distributional threshold for coral reefs and are thus expected to be the first and most affected by ocean acidification" And how do you plan to prevent upwelling? BTW, damage to Galápagos reefs occurred during super El Niño events. When upwelling is suppressed, ocean pH goes up, and corals are starved to death. -
VoxRat at 21:05 PM on 25 June 2010Ocean acidification
Arkadiusz: ? No, it's not "acid". It's acidification: a drop in pH.
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