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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

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Comments 120951 to 121000:

  1. watchingthedeniers at 11:56 AM on 13 April 2010
    Skeptical Science on steroids: the EPA response to 300,000 public comments
    By the way, has anyone seen Jo Nova's article on ABC drum? She is spinning up a storm, comments thread well over 350. She is claiming CRU is a white wash... when is the media going to cotton onto to how the deniers exploit the "fair and balanced" approach?
  2. Flowers blooming earlier now than any time in last 250 years
    hooray....... the earlier the better
  3. CO2 lags temperature
    nhthinker writes: 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. No, Barton's second and third sentences aren't about "today", they're about the EPICA and Vostok ice cores, covering the past half-million years prior to the start of the current interglacial. See where Barton refers to a "lag"? That's the data set and time period with the lag. That's what Barton is talking about, and that's what this thread is about. Continuing, nhthinker writes: 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. I discussed this in detail in my comment above. There's not really any problem here, this is pretty well understood. Then, nhthinker writes: But the Earth and life on it, have survived with many times more CO2 than we currently have. Nobody's suggesting that the Earth will not survive, or that life will not survive. The question is what will be the economic and social impacts of rapid climate change, especially things like increased drought in continental interiors (a la 1930s Dust Bowl). 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? This is actually a good question, and one that might make an interesting topic for a full post here. There have been a number of good predictions. Since this thread is about the temperature/CO2 lag in Antarctic ice cores, here's a nifty example of a test of the predictive power of climate models. The EPICA Challenge to the Earth System Modeling Community The basic idea is that in June 2004 the EPICA team released the analysis of climate data from 740,000 years of the Dome C ice core, but they only released the greenhouse gas data for the most recent 430,000 years. They invited modeling groups to make predictions about what the unreleased 300,000+ years of CO2 data would look like, as a way of testing the models. The model predictions are compared here: Modeling Past Atmospheric CO2: Results of a Challenge. Most or all of the groups produced pretty accurate predictions (see Figure 4 here for an example of a comparison of one group's predictions vs. the actual ice core CO2 data). So yes, there are lots of predictions, and in fact we can even find some nice examples which are actually on topic for this thread!
  4. iskepticaluser at 09:04 AM on 13 April 2010
    Arctic Sea Ice (Part 1): Is the Arctic Sea Ice recovering? A reality check
    Re #CBDunkerson - “Extent is easy to measure, but not particularly useful.” There’s one way in which extent of sea-ice (and snow cover) is absolutely critical - its impact on albedo. Sea ice reflects around 80 per cent of incoming solar radiation; open water absorbs about 80 per cent, and the effects of the subsequent warming can extend inland over 1000 kms. From a preliminary study by the PEW Environment Group on the CURRENT feedback impact of melting sea-ice and snow (albedo effect) and permafrost (methane release): “In 2010, the loss of Arctic snow, ice and permafrost is projected to cause warming equivalent to 3 billion metric tons of carbon dioxide, equal to 40 percent of total annual U.S. emissions.” Apparently this study is the first formal attempt to quantify these feedbacks. Its findings, if confirmed, are truly hair-raising.
  5. Arctic Sea Ice (Part 1): Is the Arctic Sea Ice recovering? A reality check
    The "Long term seasonal trends in Arctic Ice extent." graph going back to around 1870. How come this doesn't seem to match up with the temperature reconstructions of the arctic going back that far? In particular those temperature reconstructions show warming in the early 20th century (eg here), which I would have caused quite a bit more sea ice decline than appears in the sea ice reconstruction?
  6. Arctic Sea Ice (Part 1): Is the Arctic Sea Ice recovering? A reality check
    Thanks to Dr. Hogarth for this interesting post. I would like to echo his and others' comments speaking to the fact that the role of winds on modulating Arctic sea ice has long been known. The role of warmer temperatures conditioning the sea ice to be more sensitive to extreme events such as 2007 has also been established. Also, see figures below to see how the number of melt days has been increasing over the satellite record. I'm afraid the 2007 event is going to become the sea-ice equivalent of the 1998 spike in global SATs, and will be seized upon by those in denial about AGW to confuse lay people and to muddy the waters. 2010 is going to be an interesting year. How this melt season pans out will be determined, in part, by what the AO does in the next 5 months or so. Perhaps more importantly, there is a lot of young and thin ice over the Arctic basin (about 10% is covered by ice more than two years old, compared to 35% in the early eighties): Claims that the Arctic sea ice is "recovering" based on just a few data points are irresponsible and premature.
  7. Arctic Sea Ice (Part 1): Is the Arctic Sea Ice recovering? A reality check
    There seems to be a "recovery" in multiyear ice(older than 3 years) http://nsidc.org/arcticseaicenews/ http://nsidc.org/images/arcticseaicenews/20100406_Figure6.png If this is really a "recovery" is debatable, as most of this "multiyear ice" is really 3-year ice. Older ice is still at record lows. It will be nice to see an estimation of ice THICKNESS based on those sea ice ages, to see if there is any sign of recovery in ice VOLUME.
  8. Jesús Rosino at 05:50 AM on 13 April 2010
    Arctic Sea Ice (Part 1): Is the Arctic Sea Ice recovering? A reality check
    John, inline comment #10, Thanks, John. My fault, and it's not the first mess due to my quick writing (though I didn't imagine I could affect the whole thread). I'll be more careful. Peter Hogarth #11, Thank you for this post, I'm looking forward to reading the upcoming 2nd part! Let's see if I can find the time to finish the translation of this one before that :)
  9. Tarcisio José D at 05:41 AM on 13 April 2010
    Arctic Sea Ice (Part 1): Is the Arctic Sea Ice recovering? A reality check
    RE #8 OK. I read the article in your Linck. He analyzes the steam only in the vapor state. Do not analyzes the transformations vapor / fog / cloud / vapor or rain dominated the "latent heat". We need to analyze the relationship vapor/fog of 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 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. 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 by requiring 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. http://www.pnas.org/content/104/39/15248.full.pdf "Because SSM/I moisture retrievals are unavailable over the highly emissive land surface (18), our focus is on the total column water vapor over oceans, Wo, for a near-global domain." Translate this paper (portuguese/Inglish) http://www.scam.com.br/tjdavila/solo/termostato.htm
  10. CO2 lags temperature
    Nhthinker, leaving aside the multitudinous observational evidence confirming the central predictions from bulking up the atmosphere's C02 inventory, our understanding of how additional C02 will affect the primary radiative physics of the atmosphere is well understood. The sort of large scale experimentation you insist is required to understand the phenomenon and make successful first order predictions is actually not necessary. Exactly what knock-on effects will transpire from the changes to the physical behavior of the ocean-atmosphere system we're launching by altering the radiation characteristics of the atmosphere are as yet emergent. But again, the gross effects of the work we're performing on our atmosphere are not actually controversial. If I've not already done so, I suggest you spend some time reading an introduction to the topic of C02's characteristics as they pertain to radiative physics and our atmosphere. You can hardly do better for a primer on this subject than Weart: The Carbon Dioxide Greenhouse Effect And pardon me for mentioning policy. My concern is that on the one hand we do have an admirable desire for perfectionism when it comes to creating hermetically airtight science, yet on the other hand pragmatism suggests that at some point we must accept that multiple arrows of hypothesis leading to theory and then conclusion tell us we've got a need to take the conclusions we're reaching and act on them.
  11. Arctic 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.
  12. CO2 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.
  13. It'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.
  14. Skeptical 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!
  15. Arctic 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.
  16. Peter Hogarth at 03:24 AM on 13 April 2010
    Arctic 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
  17. CO2 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.
  18. Jesús Rosino at 02:57 AM on 13 April 2010
    Arctic 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 :-)
  19. Tarcisio José D at 01:56 AM on 13 April 2010
    Skeptical 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.
  20. Jesús Rosino at 01:50 AM on 13 April 2010
    Arctic 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)
  21. Tarcisio José D at 01:42 AM on 13 April 2010
    Arctic 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
  22. Jesús Rosino at 01:35 AM on 13 April 2010
    Arctic 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. -
  23. Peter Hogarth at 01:22 AM on 13 April 2010
    Arctic 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.
  24. Arctic 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.
  25. Peter Hogarth at 01:05 AM on 13 April 2010
    Arctic 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.
  26. Peter Hogarth at 00:58 AM on 13 April 2010
    Arctic 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?
  27. HumanityRules at 00:07 AM on 13 April 2010
    Arctic 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.
  28. CO2 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.
  29. Arctic 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).
  30. It'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.
  31. Skeptical 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.
  32. Miriam O'Brien (Sou) at 21:33 PM on 12 April 2010
    Skeptical 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).
  33. Skeptical Science on steroids: the EPA response to 300,000 public comments
    Damn I missed out a "not" after "work" of course!
  34. Skeptical 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.
  35. Miriam O'Brien (Sou) at 17:49 PM on 12 April 2010
    Skeptical 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! :-)
  36. Human CO2 is a tiny % of CO2 emissions
    nocompromise, yes, G (Giga) is a prefix. There are many more indeed.
  37. Skeptical 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!
  38. Human CO2 is a tiny % of CO2 emissions
    It appears that 'billion tonnes' and GTons are interchangeable?
  39. Glaciers 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
  40. Jacob Bock Axelsen at 06:01 AM on 12 April 2010
    Ocean 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.
  41. The 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!
  42. Ocean 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?
  43. Ocean 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.
  44. The 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.
  45. Ocean 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.
  46. Berényi Péter at 02:28 AM on 12 April 2010
    Ocean 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.
  47. guinganbresil at 02:11 AM on 12 April 2010
    Ocean 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.
  48. Human 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.
  49. CO2 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.
  50. CO2 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 ...

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