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CBDunkerson at 04:32 AM on 13 April 2010Arctic Sea Ice (Part 1): Is the Arctic Sea Ice recovering? A reality check
Ultimately, the only statistic which tells us which way Arctic ice is going is the total volume. Extent is easy to measure, but not particularly useful. Consider; A single cube of ice 10' x 10' x 10' in size has a volume of 1000 cubic feet and an extent of 100 square feet. If we then chopped that block up into 1000 1' x 1' x 1' cubes, tossed out 950 of them, and arrayed the remaining 50 in a 'checkerboard' pattern the resulting volume would be just 50 cubic feet but the extent would still be 100 square feet. This is because 'extent' is defined as the area of ocean with at least 15% sea ice... and thus indeed a carefully scattered 15 one foot cubes could STILL cover an 'extent' of 100 square feet. From this example we see that two equal 'extents' can represent VAST differences in ice volume and even the surface area of actual ice (i.e. it only takes 15 square feet of ice surface to create an extent of 100 square feet). Thus, something as simple as a prevailing wind causing ice to bunch up in an area or scatter more widely can have a huge impact on 'extent' without changing actual ice area (and thus albedo) or volume at all. All studies indicate that total Arctic ice volume is still decreasing. Ergo, all the talk about blips in the 'extent' data is meaningless... even if they weren't classic examples of ignoring a pronounced long term trend to focus myopically on minor short term statistical variation.Response: I wouldn't say sea ice extent data is meaningless. Just that extent shows a lot more variability than sea ice volume as extent is also affected by weather, wind, sunlight and year-to-year temperature changes (eg - an unusually cold winter will lead to greater reforming of first year ice). Nevertheless, Arctic sea ice extent is a good proxy for Arctic temperatures when considering long-term trends - you just need to be careful drawing conclusions from short-term fluctuations. -
nhthinker at 04:24 AM on 13 April 2010CO2 lags temperature
Doug, Science, by definition, has to be predictive otherwise it is not science. The middle ages was full of charts that would be constantly updated to seem predictive but never took into account the theory of gravity. These tables that the "scientists" of the middle ages were made to exhibit "self-consistency". Self-consistency is a necessary but not a sufficient condition to determine true science. Prediction while measuring other potential factors is typically necessary to be considered a hard science. Again I ask- what prediction of global warming science are you most proud of? The graph presented with this article covers half a million years. Barton's paragraph referred to even greater time scales. His assertions were correct for the timeframes he covers. Ned claims that previous points in history are not instructive to the present time at the present scale. And that new "science", that does require long term testable data, is not needed: all that is required is ever changing self-consistent models... Just like what we had in the middle ages. If this article, instead of showing half a million years, actually pointed to data sets from history that shows a substantial burst of CO2 (with similar levels of dust that are being produced today) and show that there was clearly a jump in temperatures that could not be explained by solar variation then I would take notice. What is the best unchanged global warming model that is over ten years old? What did it predict correctly? Climate is much more complicated than today's models describe and there is no historical data presented here that CO2 is a forcing function to global climate- The next 50 years will dramatically change our knowledge of climate and how humans can control it to make it more hospitable for any species humans choose. I expect the importance of ionization, solar variability, and magnetic fields will bring the actual models of decadal climate prediction to the level of today's weather prediction. I'll leave my faith in the physicists - they do not seem to be as steeped in political biases. An overemphasis on things that are observable for very long periods of time have fooled scientists in the past and are destined to continue to do so. Your last paragraph was clearly regarding policy and so I will not respond to it as that it has been deemed inappropriate to discuss policy here. -
Riccardo at 04:07 AM on 13 April 2010It's the sun
Another link between the sun and earth climate broken. It's the old Scafetta et al. 2003 hypothesis of a link between solar flares or other sun related fluctuations (e.g. Scafetta et al. 2004 and West et al. 2008) and temperature variability. In a new paper Rypdal et al. found that the claimed "complexity linking" is due to a faulty analysis and that proper tests show that the opposite is true: "These results suggest that the stochastic properties of the global temperature record is governed by the long-memory internal dynamics of the climate system and are not linked to the short-memory intermittent fluctuations which characterize the solar output." In a interview reported by physorg.com Rypdal adds: "A corresponding theory of global warming of solar origin does not exist. What does exist is a set of disconnected, mutually inconsistent, ad hoc hypotheses. If one of these is proven to be false, the typical proponent of solar warming will pull another ad hoc hypothesis out of the hat. This has been the strategy of Scafetta and West over the years, and we have no illusion that our paper will put them to silence" Quite a strong statement, I'd say. -
Ed Davies at 03:54 AM on 13 April 2010Skeptical Science Housekeeping: Preview, translations and icons
Your feed appears to be broken, according to the feed reader I use, RSSOwl. The web site Feed Validator agrees.Response: Fixed, thanks for the heads up. It was due to the YouTube animations in the latest Arctic sea ice post. Embeddable YouTube movies are a wonderful resource but they are also the bane of my WYSIWYG blogging existence! -
Doug Bostrom at 03:36 AM on 13 April 2010Arctic Sea Ice (Part 1): Is the Arctic Sea Ice recovering? A reality check
I believe I mentioned it elsewhere here but for those keen on remote sensing as it relates to Arctic ice, good news as CryoSat 2 (link to comprehensive SpaceFlightNow story) was successfully launched a few days ago. This satellite is specifically equipped to monitor draft or thickness of Arctic ice. -
Peter Hogarth at 03:24 AM on 13 April 2010Arctic Sea Ice (Part 1): Is the Arctic Sea Ice recovering? A reality check
Jesús Rosino at 02:57 AM on 13 April, 2010 Many thanks, I hadn't found those ones. Here's the link for Kwok 2010 -
Doug Bostrom at 03:16 AM on 13 April 2010CO2 lags temperature
Nhthinker, it seems to me when you repeat yourself by restating obvious and acknowledged facts such as that C02 did not trigger the end of glacial stades, when you ignore that scientists have devoted scrupulous attention to solar forcings, you're shadowboxing, arguing against nobody. Those matters are recognized and integrated into research on climate, and so far the hypotheses explaining how they fit into the big picture are functioning well as small parts of a large mechanism. You go on to say that science is at its best when it is accurately predictive and can be tested to complete satisfaction. True enough, but in this case we do not have a laboratory large enough and with the correct features to run controlled experiments on a global climate. More, there are so many variables at play here that I don't think the sort of controlled experiments you have in mind are even possible. What we can instead look to is how the burgeoning collection of research results we have from multiple disciplines fit together. Do we see observations that appear to be mutually exclusive, that cannot be explained in the presence of other observations? No. The ultimate metric of validity, the requirement for self-consistency, is satisfied despite the vast gulf between many of the avenues of inquiry related to climate change. What we have is a synthesis of multiple lines of inquiry, each yielding predictions and observations that taken together describe the gross features of our climate, features on the scale we're concerned with. For all the criticism leveled at it, that is what the IPCC report is, a synthesis, and the message of that synthesis is robust against the very most stringent criticism. Again, self-consistency-- a key metric of scientific validity-- is satisfied. Now, policy makers also do not have the luxury of being able to run experiments of a global scale in laboratories. They must operate in the day-to-day world of human affairs. Multiple lines of mutually consistent scientific inquiry tell us our human affairs are modifying the climate. Human affairs are going to need some adjustments. At a certain point we need to come to grips with the self-consistent message multiple disciplines have delivered to us and make some changes in our habits. -
Jesús Rosino at 02:57 AM on 13 April 2010Arctic Sea Ice (Part 1): Is the Arctic Sea Ice recovering? A reality check
#9 doug_bostrom, Yes, I immediatly wrote John to let him know that I had missed a bold closing tag in the first reference. I hoped he could add this closing tag, but never mind. These were the references for #2 HumanityRules: Minn et al 2008 and Mitchel et al 2009. I haven't read his two references, but I would bet they don't say or imply that the (amplified) temperature trend is not the main driver of the sea ice long-term downward trend.Response: I fixed your original comment and removed Doug's #9 response. Don't forget to use the preview button if you're posting HTML tags in your comment :-) -
Tarcisio José D at 01:56 AM on 13 April 2010Skeptical Science on steroids: the EPA response to 300,000 public comments
Re #18 "And the best climate models attempt to account for and reproduce the responses of the earth's climate to the varying influences over time, and, IMHO, do a pretty remarkably good job of it." But these climate modelers did not predict that the ammonium produced by decomposition of organic matter disperse and waterproofs the clay soil. Today, the evaporation of water on the continents is reduced and requiring to the oceans to warm up to replenish the moisture in the air. I'm trying to draw attention of the scientific world to this fact. -
Jesús Rosino at 01:50 AM on 13 April 2010Arctic Sea Ice (Part 1): Is the Arctic Sea Ice recovering? A reality check
#8 Tarcisio José D'Avila, Water vapour is a feedback, not a forcing (or here) -
Tarcisio José D at 01:42 AM on 13 April 2010Arctic Sea Ice (Part 1): Is the Arctic Sea Ice recovering? A reality check
Okay. I accept the assertion that the ice is thawing. But what is the explanation for this phenomenon?? We need to analyze the relationship vapor/fog water in the atmosphere because water vapor is the thermal battery of our planet. It's the "battery" that provides thermal energy to warm the night (no sun) and to soften the harsh winter (low sun). In summer the water and/or fog for to pass into the vapor state (potential energy - the latent heat) reducing the temperature of the planet releases this energy in the winter making it less strict. The same can be said of the temperatures of day and night. The greater the difference the winter/summer or day/night the greater the occurrence of extreme events. Defrost is an extreme event. Translate this paper (portuguise/Inglish) http://www.scam.com.br/tjdavila/solo/termostato.htm -
Jesús Rosino at 01:35 AM on 13 April 2010Arctic Sea Ice (Part 1): Is the Arctic Sea Ice recovering? A reality check
#2 HumanityRules, Well, this post is about whether there is a receovery in sea ice. The Arctic has experienced more warming than any other region in the whole world. It is difficult to imagine how this can contribute to a stable trend in sea ice. I have not read the two documents you've linked, but I would bet that none of they say or imply that temperature is not the main driver of the long-term declining trend. Anyway, I would try with these ones: Human influence on Arctic sea ice detectable from early 1990s onwards Min et al 2008 Geophys. Res. Lett., 35, L21701, doi:10.1029/2008GL035725 On the Detection and Attribution of Anthropogenic Global Warming Using Northern Hemisphere Sea Ice Extent Mitchell, John F. B. - Garrett, Donald - Robock, Alan - Parkinson, Claire L. - Walsh, John E. - Stouffer, Ronald J. - Vinnikov, Konstantin Y. - Zakharov, Victor F. - Cavalieri, Donald J. - -
Peter Hogarth at 01:22 AM on 13 April 2010Arctic Sea Ice (Part 1): Is the Arctic Sea Ice recovering? A reality check
HumanityRules at 00:07 AM on 13 April, 2010 My apologies, your first reference is actually Ogi 2009, here is a link to Ogi 2010 to which I was referring. -
cynicus at 01:21 AM on 13 April 2010Arctic Sea Ice (Part 1): Is the Arctic Sea Ice recovering? A reality check
#2 HumanityRules, this article covers the latest blog noise about a claimed recovering arctic sea ice extent, it's not about exploring the cause of the decline (or claimed recovery). Therefore, complaining about a missing explanation to link the decline to temperature increase seems a red herring to me. This site has explored the cause before in Arctic-sea-ice-melt-natural-or-man-made. And I assume that this article could have linked to the papers you mention, but do those papers add something important that was not already covered in the article (see below) or in any of the other linked papers whether sea ice extent is decreasing or increasing? The amount of Arctic sea ice can almost be regarded as a self calibrating proxy for regional temperature, but there are several inter-related dynamic factors driving the high latitude weather patterns, air and oceanic temperatures, currents, and thus ice area and thickness. -
Peter Hogarth at 01:05 AM on 13 April 2010Arctic Sea Ice (Part 1): Is the Arctic Sea Ice recovering? A reality check
chriscanaris at 23:18 PM on 12 April, 2010 Estimates of older ice, and overall average thickness and volume continued to decrease through 2007, 2008 and 2009. I don't exclude any future possibilities!, but it is sobering to look at previous "recoveries" with an eye on the trend. -
Peter Hogarth at 00:58 AM on 13 April 2010Arctic Sea Ice (Part 1): Is the Arctic Sea Ice recovering? A reality check
HumanityRules at 00:07 AM on 13 April, 2010 I am familiar with the references. Ogi 2010: The Fram strait and winter ice export is mentioned only once in passing, in the context of a paper by Shimada. From the summary of Ogi: “In addition, the polar atmosphere has displayed rapid warming. These changes probably caused the rapid sea ice loss after 1996, but the direct influence of atmospheric trend to sea ice needs to be studied”. Kwok 2010, from the conclusion: “If there is a decreased likelihood of arch formation as the ice cover becomes thinner and weaker due to warming, there is the potential for the Nares Strait to shift to a higher flow state”. You were saying? -
HumanityRules at 00:07 AM on 13 April 2010Arctic Sea Ice (Part 1): Is the Arctic Sea Ice recovering? A reality check
You can make the observation of a decline in arctic sea ice without it necessarily being linked to temperature change. Your article shows many depictions of the decline but doesn’t show that this is linked to temperature. In fact you could have mentioned two recent papers both of which describe mechanisms for ice loss from the arctic and neither of which rely on temperature increase. GEOPHYSICAL RESEARCH LETTERS, VOL. 37, L07701, doi:10.1029/2009GL042356, 2010 Ogi et al - Influence of winter and summer surface wind anomalies on summer Arctic sea ice extent Geophys. Res. Lett., 37, 3, doi:10.1029/2009GL041872, 2010 Kwok et al - Large sea ice outflow into the Nares Strait in 2007 The first describes the influence of wind for ice export in the Fram Strait and the second discusses the formation of ice arches that block the flow of thick multiyear ice out to the Greenland sea. -
nhthinker at 23:51 PM on 12 April 2010CO2 lags temperature
Ned, You said yourself that you thought Barton's "first and last sentence are about something else entirely". If you assume for a moment that Barton is not irrational and actually was capable of making a rational paragraph, then it needs to start with a reach if the sentences of a paragraph can be logically related and he is not just spewing random sentences. You have inappropriately narrowed the interpretation of the scope of his second and third sentences to global warming of today- there is nothing to justify your assertion. The CO2 produced after a warming period cannot be the cause of that particular warming period. If the argument is that additional CO2 produced necessary causes a warming period and that variability in solar influences are much less important, then the CO2 warming proponents need a better explanation of the dramatic trend change at the typical start of an interglacial. Clearly, the CO2 levels 130 Kyrs ago were not high enough to prevent the dramatic temperature trend shift at the start of the preceding interglacial. I fully understand that CO2 levels are higher today and are trending higher than they have been in millions of years. But the Earth and life on it, have survived with many times more CO2 than we currently have. Science requires models that are accurate predictors of controlled experiments or future events. What prediction of Global warming science are you most proud of? How many years into the future was that prediction? CO2 scientists tend to very much underestimate the importance of solar emission variability changes to the Earth orbit. If CO2 were a warming forcing function, then the model should predict a plateau at the start of an interglacial instead of the typical sharp peaks. Is there any literature that demonstrates how the formulas from today's global warming computer models can be applied to the previous 3 interglacials? Thanks. -
chris1204 at 23:18 PM on 12 April 2010Arctic Sea Ice (Part 1): Is the Arctic Sea Ice recovering? A reality check
If 2007 was the lowest sea ice on record, I would expect ice coverage in 2008, 2009, and 2010 to consist of a considerably larger proportion of 'new ice' and for total volumes of Arctic Sea ice through 2008 and 2009 to still be among the the lowest on record. What is more interesting is that for whatever reason new ice is still forming. The post argues that the 2007 decline was an anomalous increase in an inexorable downward trend. However, given the physically impossibility for newly formed ice suddenly to turn into multi-year ice, we can't exclude the possibility that ice coverage may indeed be showing signs of recovery. New ice by its nature will be thin and fragile. Of course, we won't know for sure for another five or ten years (unless the present seeming recovery proves illusory over the next one or two years). -
aj1983 at 22:14 PM on 12 April 2010It's land use
This topic has been a bit weak of a defence for the allegations that the trends above land (and global trends) are significantly influenced by UHI AND other non greenhouse gas influences. I think it would be nice for the climate science community to look into this more seriously, because there is an increasing amount of literature pointing into the opposite direction. -
ProfMandia at 21:45 PM on 12 April 2010Skeptical Science on steroids: the EPA response to 300,000 public comments
This is OT but I wish to offer KUDOS to John Cook because at a recent Brookhaven National Lab hosted event titled Alan Alda Brings Passion for Communicating Science to Brookhaven Lab, John Cook was hailed as somebody who was doing science messaging the right way!Response: Thanks for the kind words in your blog post, Scott. -
Miriam O'Brien (Sou) at 21:33 PM on 12 April 2010Skeptical Science on steroids: the EPA response to 300,000 public comments
@19 - Happy to note the volume and page number. Would you like the bookmarked pdf files? (It will take a while to go through them all.)Response: Whatever is easiest - just posting comments with missing arguments as you go is fine. I downloaded all the PDFs (but not with your bookmarks, of course). -
scepticmike at 20:11 PM on 12 April 2010Skeptical Science on steroids: the EPA response to 300,000 public comments
Damn I missed out a "not" after "work" of course! -
scepticmike at 20:09 PM on 12 April 2010Skeptical Science on steroids: the EPA response to 300,000 public comments
Why has this huge amount of useful work had a lot more publicity instead of the storm in a tea cup that was so-called "Climategate" Very good to see it being brought to our attention. -
Miriam O'Brien (Sou) at 17:49 PM on 12 April 2010Skeptical Science on steroids: the EPA response to 300,000 public comments
I've been going through the EPA's responses to the comments and they are excellent. I've been adding bookmarks in the pdf files so as to easily refer back to specific points. Most of the issues raised are fairly standard and already covered on SkepticalScience, but if I come across any that aren't I'll add them to your list.Response: When you add them, could you also post a comment here mentioning the argument (perhaps also including the volume and page #)? Would save me a little time in tracking it down in the EPA reports. Many thanks! :-) -
Riccardo at 16:17 PM on 12 April 2010Human CO2 is a tiny % of CO2 emissions
nocompromise, yes, G (Giga) is a prefix. There are many more indeed. -
Bern at 13:40 PM on 12 April 2010Skeptical Science on steroids: the EPA response to 300,000 public comments
RE #17: You're absolutely right, nature is not a static phenomenon. And the best climate models attempt to account for and reproduce the responses of the earth's climate to the varying influences over time, and, IMHO, do a pretty remarkably good job of it. Which is exactly why a "no disruptions" economic model is suspect, because, as the events of the past 2 years demonstrate, the global economy is also very far from a static system, and is, in fact, far more volatile than the earth's climate. (I'd hate to think what kind of climate change would be equivalent to the 1929 crash or the GFC - perhaps some of those mass extinctions from ancient prehistory?) In any event, I suspect I'll be losing a few evenings to perusing the EPA responses... the ones I've looked at so far are quite well written! -
nocompromise at 08:38 AM on 12 April 2010Human CO2 is a tiny % of CO2 emissions
It appears that 'billion tonnes' and GTons are interchangeable? -
Doug Bostrom at 06:28 AM on 12 April 2010Glaciers are growing
Another collective datapoint: Almost 90 percent of Austrian glaciers shrank in 2009, some by as much as 46 metres (150 feet), the Austrian Alpine Association (OeAV) said Friday. In a report, the OeAV said 85 out of 96 glaciers had shrunk over the past year. The biggest changes were seen in the Oetz valley in western Tyrol province, where three glaciers retreated by over 40 metres, and eight by over 20 metres. "The ice is very thin over large areas, so the glaciers are retreating very quickly," noted Andrea Fischer of the University of Innsbruck, who conducted the measurements for the alpine club. One glacier bucked the trend and expanded, but only by a few dozen centimetres. Temperatures were higher than average by about 0.2 degrees Celsius in the winter of 2008-2009 and by 2.1 degrees last summer, the OeAV noted. More: Almost all Austrian glaciers shrank in 2009
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Jacob Bock Axelsen at 06:01 AM on 12 April 2010Ocean acidification: Global warming's evil twin
Berényi Péter ... pH during an El Niño event gets higher. The problem is not too much CO2, just the opposite. In fact in 1998 NTCO2 (Salinity-Normalized Total Inorganic Carbon) in eastern parts of the Pacific got extremely low, which implies higher than normal pH. Nice graph. However, coral bleaching is when the corals are vacated of algae, the socalled Zooxanthellae, due to the fact that either photosynthetic pigment is lost or cellular adhesion is disrupted altogether mostly due to Heat Shock. pH drops only exacerbates this or may act alone. In your example, pH elevations under rising temperatures apparently do not alleviate this - which seems rather logical. -
Doug Bostrom at 04:24 AM on 12 April 2010The human fingerprint in global warming
philc, put a transparent cap on the paint can and the same thing will happen; the effect does not depend on evaporation. Or can you describe why it won't? Insulating the can reduces not only convection but also causes backscattering of energy radiating from the can. Or can you explain how it does not? I'm not concerned with illustrating this situation for you, specifically, but instead for others who may be reading comments on this thread. You of course are free to believe whatever you wish, just as my cat is free to gag up the pills I give him for the hyperthyroid condition that will kill him if it goes untreated, heh! -
Steve L at 04:00 AM on 12 April 2010Ocean acidification: Global warming's evil twin
I mentioned @59 that carbonate availability was the main negative impact of ocean acidification. I just came across this about kelp and this about promotion of bacteria at the EPOCA blog. I guess this is a rapidly growing field and we'll be learning a lot about other impacts in the future. PS. I remember something called ATOC that was going to measure global warming in the oceans and I also remember reading somewhere that ocean acidification was going to make the ocean louder (with consequent effects on cetaceans). Ah, the EPOCA site again. Anybody else 'hear' of other potential impacts? -
Steve L at 03:16 AM on 12 April 2010Ocean acidification: Global warming's evil twin
guinganbresil @62: I was wondering about that too (@23), so thanks for the map. Of course, circulation patterns are affected by AGW and coastal areas often receive excess nutrient input. It may be hard to distinguish direct acidification from CO2 emissions from indirect via changes in ocean currents from other anthropogenic sources through decomposition. But we know how much CO2 is getting dumped into the atmosphere, and we know pretty well how much of this is absorbed by the ocean, and therefore some attribution of pH change to various causes should be possible. -
philc at 03:11 AM on 12 April 2010The human fingerprint in global warming
Please read the argument again: "A comparison between satellite data from 1970 to 1996 found that less energy is escaping to space at the wavelengths that greenhouse gases absorb energy (Harries 2001)." The fact that GHG absorb some specific frequencies of outgoing radiation is not in doubt. What is in doubt is whether or not the TOTAL TOA radiation is in balance or not. The example in #81 is a flawed analogy. An open paint can will evaporate water, carrying away energy. Very, very little of the earth's water is evaporated into space. Insulating the can simply turns the apparatus into a version of a plain old greenhouse and doesn't speak to any of the mechanisms that slow the rate of energy flow in the climate system. -
Steve L at 03:01 AM on 12 April 2010Ocean acidification: Global warming's evil twin
BP @63 -- Didn't you have anything to say about my previous comment? You're at it again, saying: 1. El Niño is associated with higher pH, and 2. El Niño is bad for Galapagos corals, therefore 3. Higher pH is bad for Galapagos corals. This is a fallacious argument, because you're not accounting for impacts other than pH that are associated with El Niño (e.g., increased temperature associated with bleaching). Somewhat aside from this problem with logic, there is another specific issue here, within point 1: you say total inorganic carbon is low and "implies higher than normal pH". In my previous comment I tried to point out that the negative effects of low pH are exerted largely through making carbonate unavailable to shell-building creatures. Carbonate ion is inorganic, so low total inorganic carbon may imply carbonate undersaturation as much as it implies low pH. -
Berényi Péter at 02:28 AM on 12 April 2010Ocean acidification: Global warming's evil twin
#61 Jacob Bock Axelsen at 21:51 PM on 11 April, 2010 There was indeed large mortality of coral reefs at Galapagos during El Niño 1998 Yes. But as I've already mentioned, pH during an El Niño event gets higher. The problem is not too much CO2, just the opposite. In fact in 1998 NTCO2 (Salinity-Normalized Total Inorganic Carbon) in eastern parts of the Pacific got extremely low, which implies higher than normal pH.
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guinganbresil at 02:11 AM on 12 April 2010Ocean acidification: Global warming's evil twin
I have seen a fair amount of discussion on the effect of atmospheric CO2 on ocean surface pH. Unfortunately there has been a confounding between deep ocean upwelling and acidification from atmospheric sources. The ocean pH decreases with depth, with a minimum of around pH 7.6 at a depth of about 800 meters. When this deep water upwells to the surface it mixes and reduces surface pH. Areas that are subject to upwelling are a function of the thermohaline circulation and wind conditions near coastal regions:
Here is an example of a commonly referenced research of ocean surface pH drops attributed to atmospheric CO2 in a region subject to upwelling - Wootton (2008)
It is vitally important for the cause of sound science to look at all causes for ocean pH changes and accurately represent their relative impacts. Otherwise, this "advocacy science" will cast doubt on the whole community.
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Riccardo at 01:14 AM on 12 April 2010Human CO2 is a tiny % of CO2 emissions
nocompromise, not sure what numbers you're looking at. The data you link are fossil fuel carbon emissions which correspond to the data shown in fig.2 here. Where is the orders of magnitude difference? If instead you need to reconcile fig. 1 (29 GTons) and 2 (8 GTons), it's due to the diffent mass of C and CO2, a factor of 3.6. -
Ned at 01:08 AM on 12 April 2010CO2 lags temperature
Okay, last in a series of three comments, and sorry about being so verbose. So, what's the relevance of the time-lag in ice cores to our current situation? Not much. In the Pleistocene, CO2 was a feedback amplifying warming/cooling caused by the Milankovich cycle. Like many feedbacks, it took a while to kick in, so there was a time lag. Today, in contrast, we're directly adding CO2 to the atmosphere. It's a forcing in its own right, not just a feedback (though there are additional CO2 feedbacks). So the time lag in the ice cores is irrelevant to the current situation. Likewise, the fact that temperature stopped increasing during previous interglacials doesn't mean that temperature won't keep rising if we keep burning fossil fuels today. It stopped rising then because the M. cycle changed. But the M. cycle doesn't have any effect on the decade-to-century time scale we're dealing with now. Hopefully this clears up some of the confusion. -
Ned at 01:00 AM on 12 April 2010CO2 lags temperature
With that out of the way, let's talk about the lag itself. nhthinker writes: If you want to argue that the temperature requires CO2 to elevate which causes further temperature rise and that solar changes are NOT the primary cause of temperature changes, then you really need to explain convincingly what causes the temperature and CO2 levels to STOP their rises at the entry of interglacial periods. During the Pleistocene glacial/interglacial cycles, the primary forcing of temperature changes was variations in the seasonal and latitudinal distribution of insolation caused by variations in the Earth's orbital geometry (Milankovich cycles). Everyone here knows this. Without these spatial-temporal variations in insolation, there wouldn't have been swings in temperature. However, those changes in temperature were amplified by various positive feedbacks (e.g., water vapor, CO2, and ice albedo). Without those feedbacks, the magnitude of the temperature swings would have been much smaller. One could logically ask, if there are such positive feedbacks in the climate system, why did the temperature stop rising (or falling)? (This is the meaning of your "STOP" sentence, I believe.) There are at least two answers: (1) A positive feedback does not imply unlimited increase, as long as the feedback coefficient is between 0 and 1. Many people (on both sides of this argument) don't understand this point, and assume that a positive feedback in the climate system has to lead to either runaway warming (like on Venus) or to a frozen snowball Earth. That's incorrect, though. (2) Most importantly, the Milankovich cycles are cyclical. They alternately provide a warming forcing followed by a cooling. As soon as the direction of this forcing reversed (say, from warming to cooling), the CO2 and other feedbacks would likewise reverse (with the usual time lag, of course). So there's nothing that needs to be explained about the fact that the temperature stopped rising during the interglacials (or why it stopped falling during the glacials, for that matter). How is this relevant to the current situation? See the next comment ... -
Ned at 00:47 AM on 12 April 2010CO2 lags temperature
nhthinker, it's still not clear to me why or how you think that Barton is being misrepresented in the quote at the top of this thread. John quoted two sentences where Barton is discussing the lag between temperature and CO2 in the ice core records. Barton suggests that the existence of this lag shows that CO2 did not cause the glacial/interglacial changes in temperature ("a rise in carbon dioxide levels could not have caused a rise in temperature if it followed the temperature"). The article at the top of this thread rightly explains that Barton's point is misleading, because in the period Barton is referring to CO2 functioned as a feedback whereas now it's acting as a forcing (more on this in the next comment). You suggested that there was some context being left out, specifically the following: * A preceding sentence and footnote (iv) discussing higher CO2 levels in the Eocene and Oligocene. This is tens of millions of years ago, i.e. two orders of magnitude further back in time than the glacial/interglacial cycles that are the subject of this thread. There are no ice cores that go back that far, and no evidence for any lag. Higher levels of CO2 in the Eocene and Oligocene don't somehow change the wrongness of Barton's discussion of a lag in Pleistocene ice core data. It's a completely different subject. * A footnote (v) to a paper about the lag in the ice cores, and a concluding sentence with an appeal to authority (citing somebody from NAS who Barton says mentioned the lag in congressional testimony). These, likewise, are completely irrelevant -- all they do is provide support for Barton's claim that there was a lag in the ice core records. But nobody thinks that there wasn't a lag in the ice core records. If anybody is making a straw-man argument here, it's Barton himself! So no, I don't see anything in the extended version of the Barton quote that even remotely suggests he is being misrepresented. You will need to be much more specific if you still think there's a problem somewhere there. -
nocompromise at 00:42 AM on 12 April 2010Human CO2 is a tiny % of CO2 emissions
I'm having trouble reconciling the values presented in this article vs the CO2 amount measured in: http://cdiac.ornl.gov/trends/emis/graphics/global.total.gif and http://cdiac.ornl.gov/trends/emis/tre_glob.html (cited by the CO2 article in wikipedia) They are orders of magnitude different! Am I missing something here?Response: What I'm displaying in my carbon cycle graph is the flux of carbon dioxide. What you're looking at in the CDIAC graph is the flux of carbon. To convert carbon to carbon dioxide, you multiply by 3.66 (I explain the process in more detail here - and actually use the CDIAC data from your link). So for example, the CDIAC graph finds that our current rate of CO2 emissions is around 8000 million metric tons of carbon. This is around 8 gigatonnes of carbon which equates to 29 gigatonnes of carbon dioxide.
I opted to use units of carbon dioxide in my carbon cycle graph because I thought it would be less confusing - people relate to carbon dioxide emissions, not the carbon element of the carbon dioxide molecule. I've regretted it ever since because the convention is to use carbon and hence much confusion has ensued. I will update my carbon cycle graphs with units of carbon sometime down the track (when I get the time). -
Jacob Bock Axelsen at 21:51 PM on 11 April 2010Ocean acidification: Global warming's evil twin
Berényi Péter (...) Galapagos coral reefs are still well and alive. With emphasis on 'still', I suppose. There was indeed large mortality of coral reefs at Galapagos during El Niño 1998. During large extinction events corals are the ones who suffers the most as in e.g. the Cretaceous–Tertiary extinction event. Just because corals did not become extinct as a class so far in no way precludes that we can not drive them to extinction. -
Alexandre at 21:51 PM on 11 April 2010The human fingerprint in global warming
Is Chen 2007 peer-reviewed? In which journal? -
Berényi Péter at 20:27 PM on 11 April 2010Ocean acidification: Global warming's evil twin
I'd recommend reading Biogeosciences (An Interactive Open Access Journal of the European Geosciences Union). It has a nice Public Peer-Review & Interactive Public Discussion process and the papers are published under the Creative Commons Attribution 3.0 License, both Discussion Papers (BGD) & Final Revised Papers (BG). In most cases there is also some Supplement. This is how all scientific publication should look like. -
James Wight at 17:03 PM on 11 April 2010Are we too stupid?
This to me goes to show that websites like this one are doing their bit by working on requirement b) “the population is sufficiently enlightened about the facts”. -
James Wight at 16:53 PM on 11 April 2010Every skeptic argument ever used
John, I have some more suggestions about your list of arguments. I realize the list is not entirely your own anymore, so some of the things I point out may be other people’s additions that have slipped under the radar. (That’s the danger of allowing anybody to contribute!) In particular, somebody has added an argument with the rather unwieldy title “CO2 emissions/absortion rates from nature are largely unprecise. More unprecise than accounted emissions by humans. We can't be sure if it is all an accounting error.” Maybe this should be shortened to a single sentence like the other arguments? Also, “absortion” should be spelled “absorption” and “unprecise” should be “imprecise”. “Kilimanjaro snow does not melt because of warming” is also a bit unclear. Does it mean that Kilimanjaro snow *isn’t* melting because of warming (an argument that would belong under “Mt Kilimanjaro’s ice loss is due to land use”), or Kilimanjaro snow *wouldn’t* melt if it was warming (which would belong under “It’s not bad”)? Come to think of it, “Glacier melt is natural” itself doesn’t really belong under “Climate’s changed before” either. It seems to me that “Gulf Stream is stable” and “Conveyor belt won’t stop” are essentially the same argument – unless one is meant to refer to ocean conveyor belts generally and the other to the North Atlantic specifically, but that isn’t clear from the articles submitted. Also, I’m not sure what the difference is between “CO2 effect is saturated” and “Saturated Greenhouse Effect”. Does the latter mean that all greenhouse gases are saturated, not just CO2? I think “Freedom of Information requests were ignored” belongs under “Climategate”. And maybe “Corals survived during past periods of high CO2” should go under “It’s not bad”. (Incidentally, do you realise the “It’s not bad” link on the taxonomy page goes to an error message?) I also noticed you’ve separated the last category of arguments into two topics, “It’s too late” and “It’s too hard”. I suggest that “CO2 limits will hurt the poor”, “Famine and disease are a higher priority”, and “CO2 limits take money away from real threats” all belong in the “It’s too hard” category.Response: The list of skeptic arguments that I originally set up is like a complex garden that constantly needs pruning and maintenance to keep in order. Then I let everyone else add to it which means it now needs constant weeding also! So I appreciate your periodic proofreading of the skeptic list, helps keep it relatively under control. I've just made the following changes:- Shortened the "CO2 emissions/absortion rates from nature are largely unprecise..." argument to "Carbon cycle uncertainty is high"
- Merged the two Kiliminjaro arguments into one
- Merged "gulf stream is stable" and "conveyor belt won't stop"
- Merged "co2 is saturated" and "greenhouse is saturated"
- Recategorised "FOI requests were ignored" under climategate
- Recategorised coral reef arguments under "it's not bad"
- Fixed the broken link to the "It's not bad" page
- BTW, while I was there shuffling things around, I swapped the ordering around so "It's too hard" comes before "It's too late". If you consider the arguments as stages of denial, it makes more chronological sense.
-
Jacob Bock Axelsen at 06:43 AM on 11 April 2010Are we too stupid?
embb Geo-engineering is sure to go wrong - and any social engineering is sure to have no negative impact, as if the precautionary principle could only be applied very very selectively. According to the Milinski papers all it takes is letting people discriminate against the ones who defies scientific evidence - much like discrimination against criminals. That can hardly be considered social engineering from a historical perspective. If one finds the consequences of global warming exaggerated, then being in favour of geo-engineering would constitute a contradiction. If one does not accept climate science, the consequences of geo-engineering cannot currently be scientifically calculated. If climate science is correct and the consequences are perceived as dire, then there is no good reason to significantly increase the risks by attempting geo-engineering on top of the problems. That is, unless in an emergency where CO2 reductions alone would not suffice. -
Steve L at 04:17 AM on 11 April 2010Ocean acidification: Global warming's evil twin
BP, I'd like to take issue with your comment @50. Unfortunately I don't have time to do a good job of it, so I'll limit myself to two points. First, this form of argument -- "there's low pH at location or time X and species Y is doing okay there/then" -- is interesting but not convincing. Biochemically harsh environments like tide pools and thermal vents have species that do well in them, too, and there are shellfish in fresh water (pH below 7). One cannot conclude that critters in other environments will be unaffected by changes to pH that are within the range of "location X". For example, the shellfish doing well in fresh water (and low pH) should give us very little comfort that shellfish in the ocean are going to do fine as pH declines. Further, your suggestion that low pH is good because bleaching occurs during El Nino ignores interrelated factors that are important (eg. temperature!). The full suite of environmental parameters and ecological context (including species composition) matters. That brings me to my second point, and I repeat to some extent Riccardo's comment earlier @18. The reduction of pH is a problem because it increases the solubility of carbonate such that it forms bicarbonate which isn't very available to creatures to make their shells. My understanding is that the aragonite (a more highly soluble form of carbonate used in many invertebrate shells) saturation horizon will become shallower in the high latitudes before it changes much in the tropics (despite pH being generally lower in the tropics, in absolute terms). By 2100, the aragonite saturation horizon is projected to go from 120m (current) to 0m in the high North Pacific or Bering Sea, from 730m (current) to 0m in parts of the Southern Ocean, and 2600m (current) to 115m in the North Atlantic. For these kinds of contextual reasons, Alaska Department of Fish and Game (for example) is worried about their production of pink salmon (who feed on pteropods, who make shells of aragonite). What happens in specific coral reef locations may depend greatly on the saturation states of carbonate there, and although pH influences these states, the relationship is not so simple that the other parameters can be ignored. In summary, I think you raise interesting questions, but I don't think you can assume that corals persisting in low pH conditions in "location X" mean that corals in "location Y" will be fine when exposed to similar pH levels. You may also want to check on whether or not your beloved Galapagos corals are expected to be exposed to further decreases in pH. -
Doug Bostrom at 03:16 AM on 11 April 2010CO2 lags temperature
Nhthinker, I believe in looking at past events you're failing to recognize or at least keep in mind that what we're doing right now is to inadvertently innovate new processes that we're adding to the normal functioning of the climate. There's a lot to be learned from past events, but trying to strictly analogize between stade-interstade behavior of the climate will necessarily fail to describe what we see happening to the climate today. The researchers who have looked at past behavior of the climate have built a pretty strong case to show how those sequences emerged, how an initial rise in temperature due to solar variations triggered a feedback amplifying that rise. The exact details may still be in play, but at the end of the day it's important to remember, those events happened in the dim past and were triggered and driven by processes different than today. The burp of carbon we're eructating today actually analogizes better with other episodes better characterized as catastrophic in nature, such as periodic eruptions of flood basalt in Eastern Washington.
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