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Comments 60201 to 60250:

  1. NASA Climate 'Skeptics' Respond with Science! Just Kidding.
    Great blog post on this approach to denial: introducing 'TILT' (The Impressive Letter Technique). Love it! Includes a superb video of the world's ocean currents.
  2. Stephen Baines at 02:47 AM on 14 April 2012
    Why David Archibald is wrong about solar cycles driving sea levels (Part 1B)
    Alex C, FYI. It's rather easy to show that the OLS Y on X slope (A) and the OLS X on Y slope (B) are mathematically related via the coefficient of determination (R2) according to A*R2 = 1/B. As the R2 approaches 1, the slopes become more and more alike. This is kind of an elementary statistics 101 error. I guess it is one that's easy to make if you are trying a bunch of different things. Still, it's something one should catch.
  3. Why David Archibald is wrong about solar cycles driving sea levels (Part 1B)
    Gosh, a couple edits. Unfortunately my changes made to the post early on weren't reflected in later self-references in the post, so hopefully they're fixed now. Pardon the sloppiness in wording.
  4. Why David Archibald is wrong about solar cycles driving sea levels (Part 1B)
    Frankly this was an issue that I didn't fully recognize at first. I had mistakingly regressed the conventional way when I had tried to recreate his own regression, and thought "interesting, why would one be better than the other?" but somewhat dismissed it because I wanted to go on to other topics. It wasn't until I started getting further into my research for these posts that it started to dawn on me that this was a pretty important concept, and that my initial question did have an answer. I think though that if one isn't being too careful, it's a mistake that is rather easy to make.
  5. Why David Archibald is wrong about solar cycles driving sea levels (Part 1B)
    I updated the post to make a part early on (about minimizing vertical residuals, or dependent residuals) clearer; it was a change I had made to the structure of the post a few days ago, taking out some sentences, but apparently didn't fully mesh the two parts left over. @kiethpickering #1: I don't think so myself, at the very least for that reason but I don't think so nonetheless. His post tried to demonstrate that sea levels would fall, and whether that happened by -1.whatever mm/year or whether that happened by less (er, more? less in magnitude), it's still a fall.
  6. keithpickering at 01:19 AM on 14 April 2012
    Why David Archibald is wrong about solar cycles driving sea levels (Part 1B)
    My guess: Archibald did it both ways, and chose the method that showed the larger "relationship" between sunspots and sea level. Then he got cagey about his language in the hope that nobody would notice. Nice job noticing.
  7. NASA Climate 'Skeptics' Respond with Science! Just Kidding.
    For another take on this matter, check out: “Letter to NASA is Common Ploy in Climate Change Denial” by Nancy Atkinson, Universe Today, April 12, 2012 Michael Mann, Gavin Schmidt, and Waleed Abdalati are quoted.
  8. Daniel Bailey at 00:20 AM on 14 April 2012
    Linking Weird Weather to Rapid Warming of the Arctic
    Keep in mind, mercpl, that the ice you reference is seasonal, new ice (with some nilas ice mixed in) and historically will melt in its entirety (and rapidly, when it goes). Like the ice in Hudson Bay does. Bering Strait ice history Sea of Okhotsk ice history Hudson Bay ice history
  9. Linking Weird Weather to Rapid Warming of the Arctic
    mercpl, keep in mind that extent only requires 15% ice area... and says nothing about volume. If you look at the thickness and concentration of the ice it becomes apparent that the high 'extent' near the Bering straight currently is mostly just thin ice spread out by currents. Extent can fluctuate sharply based on (literally) a change in wind direction.
  10. Linking Weird Weather to Rapid Warming of the Arctic
    Agnostic, Are you suggesting that warming due to methane emissions is localised? Spitsbergen and East Central Siberia clathrates melt and emit methane therefore Spitsbergen and East Central Siberia warm more. I would be surprised if the effect would be so localised. BTW, what's going on with sea-ice extent this year. Seems like a hell of a lot of ice hanging around south of the Bering Straight in the northern Pacific.
  11. Data Contradicts Connection Between Earth's Tilt and the Seasons
    They might have to snip out most of the content? It appears to support the idea of a round ball-like planet going around the Sun. Might hurt sales in some regions. :p
  12. Linking Weird Weather to Rapid Warming of the Arctic
    #13 continuing RE: Antarctica... Sea ice in Antarctica is much less common in summer too. ~3 million sq km versus the ~8 million sq km that the Arctic started off with (although recently been dipping below 5 million) I think the Antarctic Circumpolar Current has also been implicated in 'insulating' parts of Antarctica (well, not like normal insulation, but as in moving heat away from certain areas), but my Antarctic knowledge is pretty weak.
  13. Linking Weird Weather to Rapid Warming of the Arctic
    Daniel Bailey, comment 13: that's a fantastically intuitive description of the difference, thanks.
  14. Data Contradicts Connection Between Earth's Tilt and the Seasons
    Yes, just had a quick search for the BBC Orbit series and it looks like it is only currently available in the UK (officially). There appears to be an episode on Youtube, but it isn't on the BBCs Youtube account so may not be there for long. It isn't clear if the BBC are trying to sell it globally.
  15. NASA Climate 'Skeptics' Respond with Science! Just Kidding.
    ...by my count they include 23 administrators,...
    OK skeptics, let's clear this up: This person is a climate-scientist: This person is *not* a climate-scientist: Any questions?
  16. Eocene Park: our experiment to recreate the atmosphere of an ancient hothouse climate
    If I can buy into the debate, Bernard J is seriously overestimating the pace of evolution. Human ancestors have been upright walkers for five million years but we still experience back problems. We have had children born with large crania for two million years, but mothers still die in child birth. Taking an extreme case, our ancestors have been fully sighted for 400 million years but we still have inverted retina. On a smaller scale, we still have lactose and gluten intolerance in populations that have relied on cows milk and wheat as major sources of nutrition for thousands of years. Evolution is typically a very slow process for any major adaption, or adaption that requires modification of multiple proteins. Adaption rates allowing full adaption with 500 generations require both a simple adaption and very high mortality or infertility rates for those who lack the adaption. When it comes to cold/heat adaption, humans - specifically Homo sapiens where largely confined to tropical Africa where we evolved up to 200 thousand years ago until about 55 thousand years ago. Consequently some human populations have only had about 50 thousand years to evolve cold adaptions. The majority of human populations, however, have always remained in the tropics and have retained the adaption for high heat required. Of those that have evolved for greater cold adaption, even Eskimos have not yet achieved the body proportions that the genuinely cold adapted Neanderthal's had. That shows that human cold adaption is still incomplete and that, for example, physiologically Eskimos are almost as well adapted for the tropics as they are for their current environment. Consequently, given time to acclimatize and general good health, no modern human population would have its survival significantly threatened by merely tropical heat. Against that, if we continue on BAU, even European latitudes will be facing significantly more than tropical heat, taking todays tropical temperatures as a benchmark. However, until temperatures routinely exceeded 40 degrees C with very high humidity, human survival and prospering will not be threatened by mere physiology. In sharp contrast human agricultural productivity will be threatened by even small rises in global temperature. This is due to a number of factors, or which the most important is likely to be a lack of year to year predictability of climate conditions in any location. Coupled to that will be large changes in climate conditions, and slow soil development rates. If, as is likely, southern European and US latitudes become arid, while the Sahara becomes wetter, we will not be able to switch agricultural production from one to the other because it will take generations for suitable soils to develop in the Sahara, or indeed in current tundra. On top of that will be issues of increase virulence of diseases (both human and crop), pest species such as cockroaches, locusts and rats, and the need to find a substitute for fossil fuels to provide the large fertilizer needs of modern agriculture. The biggest threat to human civilization in the coming century will not be from the physiological effects of heat, or even disease, but from a limited ability to feed ourselves.
  17. Doug Hutcheson at 12:08 PM on 13 April 2012
    Data Contradicts Connection Between Earth's Tilt and the Seasons
    Moderator Response: [mc] Apparently only available as video if you're in the UK!
    Darn!
  18. NASA Climate 'Skeptics' Respond with Science! Just Kidding.
    HuangFeng, I agree with you that press releases and the more advanced instructional material should contain links to relevant papers. I also think basic instructional material should contain links to more advanced material which should link to papers, so that diligent students can find their way to the relevant papers if they want to. Having said that, I find that NASA GISS is far better in this regard than every other educational or research institution I have visited on the web. Anybody interested enough can simply go to the publications tab on the side bar of their site and find a full list of publications listed under an author index, by date, and by citation. Given that the former NASA employees are complaining about a lack of substantiating science rather than just a lack of links, this means they have ignored the most publicly accessible data base of climate science papers in the world, provided by NASA. It shows that not only are they not expert in climate science, they are not even expert in basic internet aided study techniques, or at least that they have turned of those skills when it comes to climate science.
  19. Monckton Misleads California Lawmakers - Now It's Personal (Part 2)
    Hopefully the 5 legislators who attended Moncktons' misinformation session have been provided with a copy of this analysis. The article states that ... "Monckton's accusation of fraud here assumes that like a sine wave, the global temperature has zero long-term trend and will start to cool any day now". This is wrong. In a 2010 ABC interview with Monckton he asserted that “there has been very, very sharp global cooling on all measures since 2001”. Utter nonsense of course - but then what else can one expect from an eccentric? Interesting that on his slide 17, Monckton displays a portcullis and chains. This is the exclusive badge of the Palace of Westminster (where the Houses of Parliament sit) to which he has neither membership or the right to use its badge. One day the Clerk of the Parliaments may get round to summonsing him and demand he desists(?)
  20. NASA Climate 'Skeptics' Respond with Science! Just Kidding.
    Spherica @35, 36 The aim of more referencing would be to limit the influence of denial. I would say the chance of the signatories changing their stance to be very unlikely. This letter seems to have spread so rapidly amongst the numerous usual suspects that everyone has it except NASA, and must be influencing plebians. Whatever can be done to limit the influence of this non science based opinion piece should be considered. Going to extremes, I'd have journalists do actual fact checking and citing references too. I want more science! Sphaerica: Except such a request would be a waste of time - "request that the signatories identify the specific instances" For the signatories, very likely. The request would be more for the purposes of showing that NASA processes all things in a proper manner and behaves in an unbiased manner toward people, even science denying ex-employees.
  21. NASA Climate 'Skeptics' Respond with Science! Just Kidding.
    funglestrumpet @30, my noting of Wysmuller's views was on topic on this thread because it illustrated the lack of expertise of one of the former NASA employees. Further discussion of the natural or anthropogenic origins of CO2, and how we should respond to the source is, I suggest, of topic on this thread and should be taken to a more appropriate thread. Note, I am only suggesting this as a commenter, as you are responding to me, and it would be unfair for me to make that direction to you as a moderator. Being fair to you, I do not believe any SkS thread is directly related to your view point, although this thread would be as close as any. You may like to write a blog post expounding your point of view and submitting it for possible publication on SkS. Obviously I cannot guarantee publication, and the post will need to go through ordinary SkS editorial proceedures. However, I think such a post would be of interest even though I would disagree with it.
  22. Daniel Bailey at 11:09 AM on 13 April 2012
    Eocene Park: our experiment to recreate the atmosphere of an ancient hothouse climate
    Not to speak for the eloquent Bernard, but it is precisely the unusual stability of the climate since the beginning of the now-ended Holocene that has allowed mankind's techologically-based civilization to thrive. Where shall we assign the arrow with the legend: "Agriculture (and thus civilization) ends"
  23. Doug Hutcheson at 11:08 AM on 13 April 2012
    Eocene Park: our experiment to recreate the atmosphere of an ancient hothouse climate
    Sapient Fridge @ 27
    Imagine what we would think of the ancient Greeks if they had done that to us!
    IIRC, the Greeks and similar ancient civilisations pretty well deforested large swathes of land around the Mediterranean, in their search for timber to build their navies. Those civilisations destroyed an ecosystem, leaving their descendants a denuded landscape and impoverished soils, not to mention the massive changes this brought to the survival and distribution of endemic species. We also have the example of the inhabitants of Easter Island, who consumed their resources and left nothing for those who followed. Clearly, our species is not good at learning the lessons of history.
  24. NASA Climate 'Skeptics' Respond with Science! Just Kidding.
    uknowispeaksense @33 "to be fair, those webpages are directed at young school children" Some are, some are simply educational for all ages and some are news stories. I doubt even many of the better educated deniers would be able to comprehend much of the science, which requires a solid bases of the underlying web, and a likely symptom of their pseudoskepticism. I don't see a problem with early exposure to real science, particularly if more experienced people were exploring the subject and would benefit from advanced information. Much like SkepticalScience's brilliant "intermediate/advanced" options. uknowispeaksense "When I go to the doctor and he gives me advice, I don't ask him to provide a reference." Ah but you should! A good doctor will have the references or can easily access them. However many doctors have way too much research coming in to be evaluating it all on top of treating people. Add to this you have pharma companies using all manner of persuasions to push their products - and sometimes providing their version of evidence. Doctor–patient communication about drugs: the evidence for shared decision making. Fiona A Stevenson, et al. Social Science & Medicine. Vol 50:6, 2000, pp 829–840. The Reluctant Consumption of Evidence-Based Decision Making. Thomas Workmana. Health Communication, Vol 25:5, 2010 Selling sickness: the pharmaceutical industry and disease mongering. Ray Moynihan, et al. British Medical Journal, 2002, Vol 324, pp 886-891. General practitioners' perceptions of effective health care. Zelda Tomlin, et al. British Medical Journal 1999: vol 318, pp 1532-1535. A smattering of references, there are better, please forgive my short review.
  25. NASA Climate 'Skeptics' Respond with Science! Just Kidding.
    TOP @37, which one do you refer to? If it is Tom Wysmuller, then see my post @11. In a quote attributed to Werner Heisenberg, "An expert is a person who knows all the most basic mistakes in their field, and how to avoid them." Tom Wysmuller does not know how to avoid the mistake of attributing recent CO2 increase to the warming climate. Nor does he know how to avoid the mistake of treating Lamb's schematic diagram based on anecdotal evidence as a genuine reconstruction. That means he is no expert.
  26. Eocene Park: our experiment to recreate the atmosphere of an ancient hothouse climate
    @Bernard. We may not have evolved in a very warm climate, but we seem to have survived for centuries in very warm places (e.g., Africa, Brazil, India, Israel, Iraq), and we survived despite lacking much of the knowledge and technology that we have accumulated since then. I would predict that any parts of the world that end up no warmer in the future than India is now, will have people in them. We may not have evolved in those conditions, but we have demonstrated an ability to survive seemingly indefinitely in those conditions, and in large numbers. This is plain history, not theorizing about properties of human existence. You seem to have a theory that because we did not evolve under these conditions, we will not persist under these conditions. How do you explain all the people living in warm places already? I seem to be completely talking past you, because have I've said all of the above before. The way it looks to me, you have a theory. I have data. My data is inconsistent with your theory. Data wins. How could you disagree with this? Do people not live in India? Is it not much warmer there (and other places) than in most of the US? Is very much of the US predicted to become warmer in the future, than India is now? Same for Europe, Canada, Russia, portions of Africa and South America. And yes, there are predictions for a sufficiently warm world where some places become physiologically uninhabitable. That's not all places, and that's also a very warm world (+12C). And note also (from the article above): "the poles in the Eocene were 30°C warmer than today but the tropics were only a few degrees warmer". The places that are warmest now would not get that much warmer. And I should also admit that when I say "civilization", I have a pretty broad definition. We could have a ten-years-shorter expected lifespan, and it would suck, but it could still be civilization. Less nice than now (sitting in a nice rocking chair, drinking a cold microbrewed beer, tappety-tapping on my laptop, in a climate-controlled room) is pretty damn easy to imagine. And disease -- we survived untreatable disease for millennia. When my great-great-grandfather was my age, he'd been dead thirteen years, from TB probably contracted in the Civil War. Nonetheless, he survived.
  27. Daniel Bailey at 10:47 AM on 13 April 2012
    Linking Weird Weather to Rapid Warming of the Arctic
    "why it so much more pronounced than Antarctic amplification?" Antarctica is essentially a continent-sized monolithic ice block stretching more than 2 miles into the sky. The Arctic is a warm chunk of the ocean (and therefore at sea level) surfaced with a thin skim of ice surrounded by cold continents, fed by warming tendrils of currents from the Pacific and Atlantic. The proximity to the enormous thermal inertia of the world ocean means that the polar amplification is felt sooner, and much more strongly, in the Arctic than in the Antarctic. But polar amplification is already affecting the Antarctic Peninsula and the ice shelves of the WAIS, PIG and Thwaites glaciers. And in time, by the EAIS itself. EAIS = East Antarctic Ice Sheet WAIS = West Antarctic Ice Sheet PIG = Pine Island Glacier
  28. NASA Climate 'Skeptics' Respond with Science! Just Kidding.
    thepoodlebites @24, the 'correct' comparison in figure 7 on the page to which you linked is with the lime green line, which shows a composite index of land-ocean surface indices. The various indices of which it is an average are shown in figure 4. GISTEMP is among them, but shows a lower 1998 El Nino peak than does Nick Stoke's index, and much lower than does the HadCRUT3 or Zeke Hausfather's index. The inclusion of the later two indices raises the average significantly compared to GISTEMP. The GISTEMP graph you linked to shows monthly values, whereas the graph above shows smoothed values. I think they are smoothed annual values, but am not certain. Because the peak value in 1998 is so much higher than the nearby values, the smoothing reduces it significantly. In contrast, the 2005 and particularly the 2007 peaks are not so high above their neigbours, so are not reduced as much. As a result the smoothed chart gives a better idea of long term trends because the eye is not drawn to outliers, thus distorting our impression of the overall trend. For a proper comparison, you should look at the GISS annual values.
  29. Linking Weird Weather to Rapid Warming of the Arctic
    An interesting Paper, outlining mechanics responsible for changes in mid latitude weather – seemingly down to the phenomena known as Arctic amplification. But what exactly are the causes of Arctic amplification and why it so much more pronounced than Antarctic amplification? The Paper suggests Arctic amplification is caused by the slow feedbacks of more rapid losses of sea ice and snow cover. On the other hand once could argue that acceleration of these slow feedbacks is caused by, rather than causative of, Arctic amplification and that the latter is largely the product of methane emissions not evident in the Antarctic. One of the highest areas of temperature increase in the Arctic appears to affect areas in close proximity to Spitsbergen and East Central Siberia. Both of these regions are notable for sub-surface methane deposits which, due to ocean warming, are venting from the seabed and are expected to increase. If this is causative of Arctic amplification, it should be expected that this will result in continuous and accelerating loss of sea ice and land-based snow cover producing further weakening of the jet stream and higher incidence of “extreme” weather in mid latitudes. As Daniel Bailey is wont to say … we live in interesting times.
  30. Climate Scientists take on Richard Lindzen
    Re: Chris G I think that you and I have different definitions for "integrity". To me, a scientist that accuses other of manipulation of data, without looking closely at the data - and especially, who does it very publicly without attempting to contact the people that produced the data for an explanation - is not acting with integrity. It is quite conceivable that the apology was sincere. It is also conceivable that it was done in the realization that to not apologize - in view of the seriousness of both the accusation and the error committed by Lindzen - would destroy what credibility he has left, or even cost him money in a lawsuit. If he would address and correct the many other errors and distortions in the presentation, then I might be more inclined to think he has integrity. Fool me once, shame on you. Fool me twice, shame on me (or is that "you can't fool me twice"?)
  31. NASA Climate 'Skeptics' Respond with Science! Just Kidding.
    One of the signatories does have an ounce of climate expertise.
  32. NASA Climate 'Skeptics' Respond with Science! Just Kidding.
    31, HuangFeng,
    NASA should request that the signatories identify the specific instances on the NASA site, then provide links to relevant science.
    Except such a request would be a waste of time, because I think I can pretty much guarantee that these guys don't actually have anything specific. They published the letter because they deny climate change and NASA doesn't. That's as detailed as it gets for them. They're a literal embarrassment to NASA, and not in the way they had intended.
  33. NASA Climate 'Skeptics' Respond with Science! Just Kidding.
    HuangFeng, I understand what you're saying: the point of my hyperbole is that we're not talking about garden variety deniers here, we're talking about people who have a serious basis in engineering and science. They have no such excuse. The volume of climate science available in the Internet age is almost unfathomable. As uknowispeaksense says, the pages are aimed at school children. Demanding that NASA go further because retired NASA engineers and scientists might get confused and accidentally publish a refutation of NASA research... well, you can see where I keep going with this. I don't buy into your premise of "setting the grounds for more conservative initiated funding cuts," either. I seriously doubt that a crew of retired NASA employees has any more influence over government budgets than any ex-employee of any other company has over their corporate "alma mater." The bottom line is that the letter doesn't claim that NASA fails to support it's statements, it says that those statements "are not substantiated" in the sense that they are saying that the evidence does not exist. (snip) It is also flat out denial of the truth. I don't think NASA needs to change anything, except maybe to clarify for these loons (yes, "loons") that having once been a valued employee of NASA does not entitle one to careening off of the rails and putting one's voice to criticizing actively working NASA employees over something for which one has quite evidently no appreciable knowledge. What disgusts me in this affair is to look at the comments by the (snip) deniers who see these men as trustworthy heroes, whose years of gallant service entitle them to speak on this, and at the same time declaring they are somehow more qualified to do so than James Hansen. The spin the denialsphere is putting on this letter speaks volumes about where their heads are really at.
    Moderator Response: TC: Accusation of dishonesty and inflammatory comments snipped as per comments policy.
  34. Eric (skeptic) at 09:50 AM on 13 April 2012
    Linking Weird Weather to Rapid Warming of the Arctic
    Sorry Daniel Bailey, I didn't realize it was a reprint. My comment is related to the piece. As Don quotes in his comment, the AO modulates the strength of the vortex (which is shown in figure 2).
  35. NASA Climate 'Skeptics' Respond with Science! Just Kidding.
    Sphaerica, Essentially correct. Minus the "Herculean" and "dim-witted". NASA pages are (AFAIK) science based, but do not always refer to the science explicitly. I feel that the people most in denial of the extent of AGW are those least likely to seek out the science, and those in the general public on the edge of denial are much the same. NASA is a key reference site and can do so much more for clearing the path to understanding and should have enough talented researchers to simply reference the science. My guess is that the letter is setting grounds for more conservative initiated funding cuts for NASA, or denying requests for increased funding. A basic dismissal of the letter will likely not serve very well for either a funding committee or general deniers. You might catch borderline denial, but, as your handbook says, they will likely remember the message. If NASA has references to actual science then the letter fails not only from exaggeration of the credentials of the signatories, but also demonstrably fails at the premise of their argument - with evidence right at the source pages on NASA.
  36. uknowispeaksense at 09:44 AM on 13 April 2012
    NASA Climate 'Skeptics' Respond with Science! Just Kidding.
    @ Huangfeng 31. I kind of see what you're getting at but to be fair, those webpages are directed at young school children. Providing links to peer reviewed science is probably a liitle inappropriate for such a target audience. NASA cannot be expected to nor should they need to clutter these basic informative articles with references just so that idiotic deniers can't try and use them in pointless letters. One would hope that the children accessing these pages for their school projects or just out of interest are learning in their science classes that information provided by NASA can be trusted to be accurate because the work they do is subject to the rigours of peer review. When I go to the doctor and he gives me advice, I don't ask him to provide a reference.
  37. Eric (skeptic) at 09:39 AM on 13 April 2012
    Linking Weird Weather to Rapid Warming of the Arctic
    Thanks for clarifying Don. The start of the piece is Arctic amplification as shown in figure 1. Then DB says: "As high latitudes warm more than mid-latitudes, however, this north-south temperature difference weakens, which has two impacts on the jet stream [slower and more wavy]". The paper I linked in #1 theorizes that in winter the high latitude oceans retain heat while the land masses cool which increases the horizontal temperature gradient which strengthens the jet. The only difference in explanations is which temperature gradient is more dominant. It seems likely that the dominance is not constant, but varying due to factors other than the temperature gradients themselves. Kevin C, as Don has pointed out, my graph is not Arctic Amplification (or temperature) but AO, an index of Arctic pressures related to the jet stream and its undulations. Sorry for the confusion, but my diagram is related to figure 2 in the OP, not figure 1.
  38. Sceptical Wombat at 09:26 AM on 13 April 2012
    Linking Weird Weather to Rapid Warming of the Arctic
    OMG Spring Snow Extent has been increasing since 1968!
  39. Daniel Bailey at 09:23 AM on 13 April 2012
    Linking Weird Weather to Rapid Warming of the Arctic
    If Eric wishes to specifically discuss the AO more, better threads than this exist for that purpose. The subject of the OP (itself but a reprint of a well-written exposition by researcher Dr. Jennifer Francis) is "Linking Weird Weather to Rapid Warming of the Arctic".
  40. Daniel Bailey at 09:20 AM on 13 April 2012
    Linking Weird Weather to Rapid Warming of the Arctic
    "Don9000, it's pretty much the same" Actually, Don9000 has the right of it. The only thing the two terms have in common is the word "Arctic". AO and AA are to each other as weather is to climate or polo is to golf. One describes a meteorological conditional with a short temporal sphere of influence; the other describes in a summary fashion the net effects of forcings and feedbacks in the polar regions. That the South Pole experiences polar amplification differently than does the North Pole is entirely due to the vagaries of geography/geomorphology.
  41. NASA Climate 'Skeptics' Respond with Science! Just Kidding.
    HuangFeng, So, just to be clear... you're not saying that NASA makes unsupported statements. You're saying that NASA doesn't go to sufficiently Herculean lengths to make sure that even the most dim-witted retired NASA engineer or astronaut would be able to find and read the supporting material so that they can ascertain for themselves that the statements are well based in science, and also to do so before they publicly publish an outlandishly ignorant letter criticizing NASA for making statements that are "not substantiated, especially when considering thousands of years of empirical data." Do I have this right?
  42. NASA Climate 'Skeptics' Respond with Science! Just Kidding.
    Moderator Response: [Sph] Please provide references for your assertion (and theirs) that NASA has produced a "statement without reference." That whole part of their letter confuses me. NASA conducts an amazing amount of science, generates a lot of knowledge and papers that contribute to the knowledge, and produces what are fairly detailed and informative articles. What exactly are these "unproven remarks in public releases and websites" to which they (and you) are referring? Note that I am not saying unproven, proof being a loaded word. Also I am not going as far as their statement, hence my careful wording "faint hint". I would like to see NASA's site better referenced to decrease this sort of denial. We know what deniers are reluctant to perform a literature search. If references, and even better: links were to be provided then you would force them into denial of science rather than lazy hand waving of the letter, claiming the statements are unsupported. NASA What is climate change Cold Snaps Plus Global Warming Do Add Up NASA Study Predicts More Severe Storms With Global Warming Earth Impacts Linked to Human-Caused Climate Change As opposed to The Ups and Downs of Global Warming Again, because the letter provides no specific examples there is no real recourse to tackling the science that the signatories are allegedly wanting. Mind you, you would not list specifics in such a letter, perhaps an appendix if you were diligent. NASA should request that the signatories identify the specific instances on the NASA site, then provide links to relevant science. The task should take a couple research students a few weeks of work, of course this is dependent on the signatories actually being concerned about science rather than just simply attempting to raise doubt.
  43. Linking Weird Weather to Rapid Warming of the Arctic
    Eric, I still think you are talking about oranges when Bailey is discussing apples. I will wait for him to clarify the issue, but . . . If you click on the Arctic Amplification link in the post, the explanation of the term includes this definition: "“Polar amplification” usually refers to greater climate change near the pole compared to the rest of the hemisphere or globe in response to a change in global climate forcing, such as the concentration of greenhouse gases (GHGs) or solar output (see e.g. Moritz et al 2002). Polar amplification is thought to result primarily from positive feedbacks from the retreat of ice and snow. There are a host of other lesser reasons that are associated with the atmospheric temperature profile at the poles, temperature dependence of global feedbacks, moisture transport, etc. Observations and models indicate that the equilibrium temperature change poleward of 70N or 70S can be a factor of two or more greater than the global average." Thus, as I understand the Arctic Oscillation, which has to do with atmospheric pressure variations and not "greater climate change near the pole", it is not the same as Arctic amplification The AO is defined by the National Snow and Ice Data Center as follows: "An atmospheric circulation pattern in which the atmospheric pressure over the polar regions varies in opposition with that over middle latitudes (about 45 degrees North) on time scales ranging from weeks to decades. The oscillation extends through the depth of the troposphere. During the months of January through March it extends upward into the stratosphere where it modulates in the strength of the westerly vortex that encircles the Arctic polar cap region. The North Atlantic Oscillation and Arctic Oscillation are different ways of describing the same phenomenon."
  44. Linking Weird Weather to Rapid Warming of the Arctic
    Eric: I see what you're saying in terms of the effects on the jetstream being similar, but Arctic amplification looks nothing like the graph you show above. Look at this figure: Arctic amplification describes difference in rate of warming between the Arctic and the rest of the planet. As you can see, there is no significant difference before about 1980, but after 1995 the difference goes through the roof.
  45. Eric (skeptic) at 07:05 AM on 13 April 2012
    Linking Weird Weather to Rapid Warming of the Arctic
    To followup my first comment, here's a post with an AO description and although the chart there is a little out of date: it looks like the long term trend is still positive. Although variable, this past winter's AO index was mostly positive. See http://www.cpc.ncep.noaa.gov/products/precip/CWlink/daily_ao_index/ao.sprd2.gif
  46. funglestrumpet at 07:04 AM on 13 April 2012
    NASA Climate 'Skeptics' Respond with Science! Just Kidding.
    Yet again the debate gets bogged down in where this pesky CO2 comes from. If it were from some unidentified non-human source, would it be o.k. to ignore it and let the planet just go on heating up? I rather think not. If these people think that CO2 does not act as a greenhouse gas if it comes from a non-human source, all they have to do is prove it. Being ex NASA and obviously all wise in all things scientific, they surely have the evidence at their finger tips. However, until such evidence is forthcoming, we have to accept that the planet is heating up relentlessly, as several recent items on this site have clearly shown and the curret science is that that heating is largely due to the greenhouse effect of CO2, period. Unless we want future generations to suffer, we would be wise to reduce the atmospheric CO2 content by what ever means possible and as quickly as possible. (And that would still be true, even if the heating were due to the Sun, say, or some other cause.) As we remember the sinking of the Titanic, we can consider whether these ex-NASA experts, had they been in charge of the ship, would have even tried to steer away from the iceberg. Let's face it, the iceberg could hardly be said to be human in origin and the origin of things seems to be the issue that rattles their cage. Looking at their letter, it seems to me that they would have just carried on full-steam ahead, which probably explains why they are described as 'former' NASA employees.
  47. Eric (skeptic) at 06:50 AM on 13 April 2012
    Linking Weird Weather to Rapid Warming of the Arctic
    Don9000, it's pretty much the same, the positive AO described in the paper I linked is a measurement corresponding to a stronger polar jet (i.e. 500mb zonal winds in figure 2).
  48. NASA Climate 'Skeptics' Respond with Science! Just Kidding.
    While I respect the bravery and talents of NASA astronauts in their fields of endeavor, I've heard and seen enough from some former NASA astronauts to conclude that they are not all brilliant polymaths. When I was initiated into an honorary society a number of years ago at Florida State University, I had to listen to a keynote address by Norman Thagard, an astronaut and engineer, and a graduate of my university. Thagard's message was filled with so much optimistic mush that was in direct contradiction to the reality that people like me were experiencing that I wanted to walk out of the auditorium. Similarly, just because the late James Irwin was an astronaut, does not mean that experience lends credence to his belief that Noah's Ark was waiting to be found on the side of Mount Ararat in Turkey. On the other hand, his belief (so strong that he was involved in several expeditions to the mountain in search of the Ark) does show us that at least one astronaut has held a rather strong belief in the veracity of the biblical flood story. I'm reasonably sure few astronauts are similarly fundamental in their world views, but it does point out the flaw in trying to imply that because a person is an astronaut we have to accept what he or she utters as the equivalent of Holy Writ.
  49. Data Contradicts Connection Between Earth's Tilt and the Seasons
    That was a good series, Paul D, and it even gave a good explanation of the tilt/wobble/orbital changes that lead to and out of ice-ages. Orbit : Earth's Extraordinary Journey
    Moderator Response: [mc] Apparently only available as video if you're in the UK!
  50. Data Contradicts Connection Between Earth's Tilt and the Seasons
    We recently had a very good BBC TV series in the UK about Earths orbit around the Sun and how it determines the seasons/weather. One point made was that the summer in the Southern Hemisphere is generally cooler than in the Northern Hemisphere, basically because of the land mass in the North and the greater water mass in the South. Well worth watching if you get the chance.

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