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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 95201 to 95250:

  1. A Swift Kick in the Ice
    muoncounter (RE: 162), All I'm saying is that 30 years is not nearly enough time to establish an accurate range of variability.
  2. A Swift Kick in the Ice
    Rob Honeycutt, "what is so blatantly obvious" What exactly is so blatantly obvious? That there's clear downward trend in Artic sea ice since the start of the satellite record, or that anthropogenic global warming is the cause of the decline? The former is not in dispute.
  3. A Swift Kick in the Ice
    johnkg (RE: 160), "Does this upward trend mean anything to you?" Not much. It's ant crumbs - barely outside the margin of error.
    Moderator Response: [DB] Handwaving and denialism is a poor substitute for facts.
  4. A Swift Kick in the Ice
    Muoncounter... "Sure, satellite data may be 'better' than prior data..." And... the mere fact that the satellite data very closely mirrors the other data sets should give one confidence in all the other data. That's just how it works! It seems far too convenient to dismiss data that you don't want to accept when the data is obviously corroborated via multiple sources.
  5. Skeptic arguments about cigarette smoke - sound familiar?
    Here's a good link illustrating "the tobacco strategy" as used by AGW deniers.
  6. A Swift Kick in the Ice
    Sadly, RW1 has is doing little more than pulling a page from the same tired old denial playbook. Worse still, it's a game that's gone on here before. With 'I don't think its nearly enough' RW1 rejects 30 years of data as an insufficient sample. With 'I'm looking at UAH and RSS,' and 'I tend to only trust satellite on this', RW1 restricts his world to a 30 year dataset, thereby setting up the inevitable infinite loop: Thirty years is all we have; thirty years isn't enough to tell what's happening. We saw this earlier in this thread with ice extent data. Sure, satellite data may be 'better' than prior data (whatever 'better' means here), but that does not mean that prior data are all wrong. I was in the oil business way back in the pencil and paper days; when computer-aided mapping came out, there was a rush to replace anything hand drawn because the computer maps were 'better'. Trouble was, we'd found a heck of a lot of oil and gas with those hand drawn maps. They weren't wrong. In this case, standards exist: "Thirty years was chosen as a period long enough to eliminate year-to-year variations." You don't get to simply declare 'I don't think 30 years is long enough'; that may be your opinion, but if you base your scientific conclusions on opinions, you do so at the risk of all credibility. But this is an ice thread, not a temperature thread. There are plenty of those. Detailed temperature analysis comments should go to the appropriate thread.
  7. A Swift Kick in the Ice
    RW1 - 30 years is plenty of time for statistical significance, as has been well established by looking at the year to year variability. In particular, look at the first figure here, where sea ice minimum extent is multiple standard deviations below previous values and trending steeply downward. I will point out that your repeated "I don't trust anything but the satellite data" statements, joined with your claims that a 1922 article establishes high variability, are rather contradictory. That said, all data is worth something, whether it's Viking reports on sea ice levels from a 1000 years ago or current satellite data - you just have to consider coverage, accuracy, and consistency. The Walsh data drops in accuracy pre-1953, but that's still >50 years of accurate data and best estimates for before that. Now: your initial queries were regarding albedos. That was covered more than extensively on the Lindzen and Choi and the Chemistry of CO2 Absorption threads, not to mention here, where multiple people demonstrated that a simple albedo and gain calculation was insufficient and incorrect for calculating climate response. Exactly what objection to the observed Arctic icecap retreat are you trying to raise? This discussion would benefit greatly from some clarity on that question.
  8. A Swift Kick in the Ice
    #159. Thanks Rob #157. RW1, Does this upward trend mean anything to you?
  9. A Swift Kick in the Ice
    If I take Roy's 13 month running average and put a trend line across the top of it this is what I get.
  10. A Swift Kick in the Ice
    re: 153... I have to say, I always find it interesting that Roy Spencer never adds a trend line to his data.
  11. A Swift Kick in the Ice
    johnkg (RE: 155), "I see a pretty clear upward trend in that graph." No, you are absolutely correct, there is an upward trend of about 3-4 tenths of a degree over the period. Other data sets show a little more, about 4-5 tenths of a degree.
  12. A Swift Kick in the Ice
    I have to say, I am continually fascinated as to how and why people such as RW1 (who is obviously no dummy) can look at the preponderance of evidence pointing to one clear answer, but still look at small pieces of superficially anomalous information (slightly increasing Antarctic sea ice extent) and believe it somehow cast doubt on all the other evidence. I don't mean this to be an indictment of his capacity to comprehend this stuff. That's obviously not the case. But I just don't understand why it's such a challenge to accept what is so blatantly obvious, while at the same time grasping so fearlessly at the smaller contradictions.
  13. A Swift Kick in the Ice
    #153. I see a pretty clear upward trend in that graph. Source data for that graph taken from here: http://vortex.nsstc.uah.edu/data/msu/t2lt/uahncdc.lt. Its the global column (3). Maybe a chartist can bung a line on it and prove me wrong :)
  14. Link to skeptic rebuttals with short URLs
    Great tool for the tweeting world.
  15. Skeptic arguments about cigarette smoke - sound familiar?
    Another analogy is "everyone knows co2 causes warming, but it's not enough to warrant alarm or government regulation"~"everyone knows smoking causes cancer, but 2nd hand smoke is not nearly strong enough to cause problems or warrant government regulation".
  16. Monckton Myth #13: The Magical IPCC
    Moderator, please note that I stated that the proxies were for the NH, at no time have I stated otherwise. Furthermore, we should compare proxy temperatures with proxy temperatures not instrumental records. Personally, I do not care if the temperature in 1010 was slightly hotter or colder than 2010 but we should compare like with like. It is statistically and physically incorrect to compare recent instrumental temperatures with 1000-year old proxies. Marcus, from Figure 6.10c, the rate of rise in proxy temperatures from approximately 950 to 1000 looks very similar to the rate of rise in proxy temperatures from 1940+ but I do not have the original data to make a more accurate comparison. I disagree that my comparison is odius. You have stated other factors appear to have caused the MWP and I do not disagree with these other factors but the fact remains that the MWP was relatively warm (in the NH at least). Why haven't the proxies been updated so that we can compare recent proxies with the 1000-year old proxies? This would also allow comparison between recent proxies and recent instrumental records. I reiterate that Figure 6.10c of AR4 shows similar proxy temperatures 1000 years ago to the most-recent present-day proxies. If anyone has a problem with that then please contact the IPCC; they produced the diagram not me.
  17. A Swift Kick in the Ice
    Marcus (RE: 146), "Thanks for shooting yourself in the foot again RW1.You claim 30 years isn't sufficient data, but apparently a single month is?!?!" No, it's pretty meaningless. The point is it shows how much the temps can fluctuate from year to year. That's all.
  18. Skeptic arguments about cigarette smoke - sound familiar?
    Michael sweet: "Climate skeptic Richard Lindzen has testified in court that the link between tobacco and cancer is not proven." I hadn't heard that. Was that in "Merchants of Doubt"?
  19. A Swift Kick in the Ice
    Marcus, Here is what I'm looking at:
  20. Deep ocean warming solves the sea level puzzle
    HumanityRules #17: You seem to misunderstand my post. It's not about what I like or not, it's just a report of this new study. I'm only reporting what they say in their article. On the mismatch between Purkey & Johnson and this new study, you need to remember that Purkey & Johnson's data is sparse and one point of this new study is to emphasize that there are regional differences in deep ocean warming trends which might be important. The references of the figures used are here quoted from the Song & Colberg article: "Satellite altimeters have observed a global mean SLR of 3.11±0.6 mm/year since 1993 until 2008 [Ablain et al. 2009]." "These in-situ measurements include using conductivity, temperature and depth (CTD) sensors, expendable bathythermographs (XBT), and Argo floats (Argo), which give a rate of 1.2±0.8 mm/year for the same period [Willis et al. 2004; 2008; 2009; Ishii and Kimoto 2009]." "In addition, GRACE (the Gravity Recovery and Climate Experiment) data infer an ocean-mass change of 0.85±0.5 mm/year over 2002-2008, after corrected by a glacial isostatic adjustment (GIA) model [Paulson et al., 2007]."
  21. Link to skeptic rebuttals with short URLs
    Really useful. Very easy.
  22. A Swift Kick in the Ice
    18 Tom Curtis Your problem is that pointing out accurate facts is considered disengenious. At no point in #16 do I suggest what is forcing climate change today. As you suggest Holocene Climactic Optimum is an example of polar amplification forced naturally. It may give you palpitations but it's true.
  23. A Swift Kick in the Ice
    RW1: Seriously, if I'm to believe that complex of a series of factors is likely causing the Antarctic sea ice to grow inspite of 'global warming', why should I not believe that an equally numerous and complex series of factors, and not primarily 'global warming, is what's causing the Artic sea ice to melt? It has already been pointed out to you several times now that the geography is significantly different. The Arctic is significantly warmer than the Antarctic because of those differences. Remember "Global Average Temperature" means exactly what it says. Its that average of global temperatures. The earth does not heat or cool evenly. Why would we expect it to do so. (*BTW, I don't doubt the reasons for the Antarctic increasing sea ice extent are numerous and complex, nor do I doubt that many of the listed mechanisms could very well be playing a role.). Everyone has been presenting evidence to help you understand why there is a difference between the mechanisms in play at the poles. So far you have ignored all of the evidence and simply stated you don't believe. A true skeptic would recognize that evidence, weigh it, ask questions and express concerns if any. How about in the spirit of learning and understanding you give us specific empirical evidence why you don't believe. "observed" in what way? I tend to only trust the satellite data on this. If you only trust satellite data, then why do you cling to a 1922 anecdotal news article and throw out instrumental records in favor of proxy's in the MWP graph. 3 or 4 tenths of degree warming in 30 years is the most rapid warming ever observed? Actually it is more than that which has already been pointed out to you. Can you show data to the contrary?
  24. Miriam O'Brien (Sou) at 01:18 AM on 21 February 2011
    Link to skeptic rebuttals with short URLs
    Hey, that's excellent. I often post links to these topics and the short urls make it a lot easier.
  25. Link to skeptic rebuttals with short URLs
    Just waiting for Pop Tech to post up that these are not real short URLs ;)
  26. Skeptic arguments about cigarette smoke - sound familiar?
    A poor attempt to tar all sceptics with the big tobacco brush.
    Moderator Response: [Daniel Bailey] Mac is making use of analogy; taking a generalization to be all-inclusionary does not necessarily follow. Nice mental imagery, though, with the "tar" & "tobacco brush" verbiage.
  27. Deep ocean warming solves the sea level puzzle
    Avi, This seems like an extraordinary over simplification. You like the model result but fail to mention that Purkey & Johnson have attempted to use observational data to do exactly the same. They find 0.14(0.053+0.093)mm/yr SLR from the deep. That's close to a magnitude lower than the model. If the model fails to match the data shouldn't we question the model? I like the confidence of the title for this article but it seems completely misplaced. Ari I'm also curious where you got the two estimates for the first paragraph? Apart from the fact that you didn't state any dates for those estimates I'm not aware of any recent attempts to close the sea level budget in the literature that gave those figures. Here's four recent one's I've found which focus on the 2003-2007 period. Could you provide a reference for the numbers you use? Chang et al (2010) STERIC −0.11±0.22 MASS 0.70±0.34 TOT 2.67±0.52 Willis et al. (2008) STERIC −0.5±0.5 MASS 0.8±0.8 TOT 3.6±0.8 Leuliette and Miller (2009) STERIC 0.8±0.8 MASS 0.8±0.5 TOT 2.4±1.1(2.7±1.5) Cazenave et al. (2009) STERIC 0.37±0.1 MASS 1.9±0.1 TOT 2.5±0.4
  28. Link to skeptic rebuttals with short URLs
    awesome cool John!
  29. Deep ocean warming solves the sea level puzzle
    zinfan94 #12 How does this paper fit with NOAA chart which shows flat OHC from ARO 2003-2010 since the step jump of the 2002-2003 period? See here: http://www.nodc.noaa.gov/OC5/3M_HEAT_CONTENT/
  30. Captain Pithart at 22:36 PM on 20 February 2011
    Link to skeptic rebuttals with short URLs
    very nice, thank you! p.
  31. Skeptic arguments about cigarette smoke - sound familiar?
    @Sphaerica: Good point. Smoking puts more particulate matter in to the atmosphere, which, in turn, reflects incomming sunlight, thus cooling the earth. So, if you care about global warming, smoke 'em if you've got 'em!
  32. A Swift Kick in the Ice
    TOP @115: 1) You aresimply wrong about outgoing radiation and the ocean. To quote from the first link: "The best up to date measurements of ocean emissivity in the 8-14 μm range are 0.98 – 0.99. The 8-14 μm range is well-known because of the intense focus on sea surface temperature measurements from satellite. From quite ancient data, the average emissivity of water across a very wide broadband range (1-100 μm) is 0.96 for water temperatures from 0-30°C. The values from the ocean when measured close to the vertical are independent of wind speed and sea surface roughness. As the angle of measurement moves from the vertical around to the horizon the measured emissivity drops and the wind speed affects the measurement significantly." An emissivity of 0.96 is higher than that of land, or land plants in the IR spectrum, so rather than ocean emitting less outgoing radiation than land, it emits more. I have seen this in IR cameras over the sea, with the sea surface being bright due to high emissivity while the land of nearby islands are dark due to a relatively lower emissivity and cooler night time temperatures. 2) You wish to adjust the OLR radiation indicated on the graph for the lower unit area per degree latitude at the poles, but you have failed to notice that the scale is already adjusted to compensate for exactly that effect. I even made a note about it. Consequently no further adjustment is required, and the OLR from arctic areas is proven to be substantive by that graph (or more particularly, by the satellite observations summarized in that graph). 3) Ignoring the fact that you repeat the error you discussed in point 1, you are also ignoring the fact that emissivity and absorptivity of different substances vary at different wavelengths. Snow and ice are very good reflectors of visible light. The may or may not reflect UV light well, but as you can become easily sun burnt while swimming, I suspect that they doe not. They certainly do not reflect IR radiation well, instead absorbing it almost completely. In consequence, they are also almost perfect emitters of IR radiation, having about the same emissivity as liquid water. Further, it is quite true that the impact of green house gases depends on the brightness temperature of the outgoing radiation. However, at the tropics, incoming solar radiation greatly excedes the Outgoing Longwave Radiation. The difference, the excess heat, is carried to the poles by air and water currents. Consequently, if GHG's trap 10% more of OLR, they trap less than 10% more of the incoming energy from the sun. If 1/3rd of the incoming energy is transported to the poles, than energy transport by OLR by 10% only results in a net forcing of 6.7% of the incoming solar radiation. In contrast, at the poles, the energy transported by OLR is much greater than that recieved from the Sun. If a third of the incoming energy at the poles is from surface heat transfer, then trapping an additional 10% of OLR energy transfer will trap an additional 15% of the energy incoming from the sun. That means adjusting the energy trapped by OLR is a more efficient driver of temperature at the poles than at the tropics. It really is that simple. But ignoring the actual mechanics involved, or adhering to simply non-physical theories about sea surface emissivity as you are doing will blind you to the fact.
  33. A Swift Kick in the Ice
    Just one more point, though-you do realise that there has been channel data difficulties with the satellites since the start of this year? RSS has actually ceased data collection since the end of last year-& the main AMSU-A channel (channel 04) is currently off-line. So I'd like to know where you're getting that data for January 2011.
  34. A Swift Kick in the Ice
    Here's the point, RW1, if-as you claim-year to year fluctuations are sufficient to wipe out all the warming that's occurred since 1979, then why has the global temperature for the 2000's *never* been as cool as any of the years of the 1980's? Surely we should have had a whole year as "cold" as the 1980's given that solar activity for this decade has been at its lowest since the start of the 20th century.
  35. A Swift Kick in the Ice
    "You appear to be referring to deviation from the average. I'm referring to actual changes in temperature from year to year." Nope, that's just what you want to believe. I'm actually looking at comparing each 12-month period to the 12-month period that follows it &-guess what-it doesn't change by "up to 0.5 degrees" as you claim. Also, I notice you're relying on UAH data, which has already been proven to be the *least* accurate of all the temperature data (ground & land based). Its the preferred data-set of denialists, of course, because it shows the slowest rate of warming-surprise, surprise. As I said, though, nice little thread-jack.
  36. A Swift Kick in the Ice
    "According to UAH, January of this year came back down to -0.01 C below the 30 year average. You're making a mountain out of mole hill with this data. The temperatures don't do anything but go up and down from year to year." LOL. What was I saying about you denialists leaping on even the most insignificant pieces of data to "prove" their point? Thanks for shooting yourself in the foot again RW1.You claim 30 years isn't sufficient data, but apparently a single month is?!?! So what if the UAH data is showing January sitting at around the 1979-2000 average? despite your increasingly ignorant claims, the temperatures don't just simply "go up & down from year to year". They're actually *trending upwards*. The average temperature anomaly for the 1980's is -0.06 degrees, the average temp anomaly for the 1990's is +0.08 degrees (a difference of 0.14 degrees) & the average temp anomaly for the 2000's is +0.53 degrees ( a difference of 0.45 degrees). So its a clearly *accelerating* warming trend. Still, as you're a typical denialist who twists the facts to suit himself, I really don't see the point in dealing with you anymore. Congrats on your thread-jack though-another typical denialist strategy. Now go & hang out with your other denialists-unless you actually now have something remotely *intelligent* or *relevant* to say!
  37. A Swift Kick in the Ice
    Marcus, "So, to further make my point-according to the RSS data, the only time you get a year to year fluctuation of *more* than 0.3 degrees is 1997-1998 (where it went from +0.10 degrees to +0.55 degrees-a change of +0.55 degrees-a change of 0.45) followed by 1998-1999 (where it went from +0.55 to +0.09-a change of 0.46 degrees). So no there are no changes of "up to 0.5 degrees"-only a *single* change of 0.45 degrees. The rest are closer up to 0.2 degrees per year, with the occasional 0.3 degrees per year (usually corrected the following year) as I've already said." You appear to be referring to deviation from the average. I'm referring to actual changes in temperature from year to year.
  38. A Swift Kick in the Ice
    So, to further make my point-according to the RSS data, the only time you get a year to year fluctuation of *more* than 0.3 degrees is 1997-1998 (where it went from +0.10 degrees to +0.55 degrees-a change of +0.55 degrees-a change of 0.45) followed by 1998-1999 (where it went from +0.55 to +0.09-a change of 0.46 degrees). So no there are no changes of "up to 0.5 degrees"-only a *single* change of 0.45 degrees. The rest are closer up to 0.2 degrees per year, with the occasional 0.3 degrees per year (usually corrected the following year) as I've already said.
  39. A Swift Kick in the Ice
    Marcus (RE: 139), "The other point is that, as the data shows, regardless of what the year to year fluctuations are, the minimum & maximum anomalies are shifting up-by around +0.1 degrees-per decade." Actually, the data I'm looking at is showing more like +0.15 C per decade. "i.e. year to year fluctuations have yet to even bring the planet's temperatures back to the averages of the 1990's, let alone the averages of 30 years ago." According to UAH, January of this year came back down to -0.01 C below the 30 year average. You're making a mountain out of mole hill with this data. The temperatures don't do anything but go up and down from year to year.
  40. A Swift Kick in the Ice
    "I'm looking at UAH and RSS. Both show year to year fluctuations up to 0.5 C. Now the temperature departures from the average don't show this much variation but that's to be expected." You're totally full of it RW1. I've got the RSS data right in front of me &-with the exception of the strong El Nino year of 1998-1999, there was never a year-to-year fluctuation of more than 0.3-& even the 0.3 degree fluctuations are rare. Most of them are closer to 0.1 to 0.2 as I already said. All of which deliberately ignores the fact that the baseline anomaly for each decade is climbing by around 0.1 degree per decade. Hardly something that can be easily ignored. Still, I was wondering how long it would take for you to resort to outright fabrication to make your point.
  41. A Swift Kick in the Ice
    Oh &, before you ask-RSS (satellite) data shows similar year to year fluctuations in the temperature anomalies-with the sole exception of 1997-1998, & 1998-1999 (a change of +/-0.45 respectively). You see, what you clearly fail to understand about year to year fluctuations is that they're usually *corrected*, but still the underlying minima & maxima continue to rise (so for the 1980's, its -0.25 & +0.09; for the 1990's its -0.18 & +0.55-for 1998 only-though its most commonly +0.15; for the 2000's, its +0.08 to +0.55-though its most commonly +0.3 degrees. Again, notice the *trend*).
  42. A Swift Kick in the Ice
    Marcus (RE: 139), "GISS global temperature anomalies. Maybe you should check out the data before you go running off at the mouth-especially when you consider that this represents the average anomaly for the entire globe." I'm looking at UAH and RSS. Both show year to year fluctuations up to 0.5 C. Now the temperature departures from the average don't show this much variation but that's to be expected.
  43. A Swift Kick in the Ice
    RW1 (Re:138) GISS global temperature anomalies. Maybe you should check out the data before you go running off at the mouth-especially when you consider that this represents the average anomaly for the entire globe. Its worth noting that the +0.6 degrees of warming over the span of the *entire* Medieval Warm Period was sufficient to wipe out 3 major civilizations (The Anasazi, the Mayans & the Khmer Empire)-so yes there is something to be concerned about. The other point is that, as the data shows, regardless of what the year to year fluctuations are, the minimum & maximum anomalies are shifting up-by around +0.1 degrees-per decade. i.e. year to year fluctuations have yet to even bring the planet's temperatures back to the averages of the 1990's, let alone the averages of 30 years ago.
  44. A Swift Kick in the Ice
    Marcus (RE: 135), "Another typical denialist cult argument, RW1. You clearly haven't even got a *clue* how the temperature anomalies work-or the warming trend-or you wouldn't make such a blindingly ignorant comment. In fact there are no 0.4 to 0.5 degree fluctuations in temperatures, as you claim. Average year-to-year fluctuations are more on a scale of 0.05 to 0.2 degrees." What data are you looking at specifically?
  45. A Swift Kick in the Ice
    The point, RW1, is that your reliance on all the tried-&-true Denialist myths exposes you as yet another resident of the Denialist Cult. As such, I really don't think there's any point in people trying to further address your "concerns"-given that everyone has already been sufficiently patient in the face of your increasingly ludicrous claims. Maybe you should go hang out with your mates Anthony Watts & PopTech, as they have about the same weak grasp on reality as you do.
  46. A Swift Kick in the Ice
    "What statistical circles? I don't think it's nearly enough. I would think at least a 100 years would be needed to get an accurate picture - perhaps even longer." Yet another typical Denialist Argument. Even if we had 100 years of satellite data, you'd still say it wasn't enough-you & your denialist mates keep shifting the goal-posts of what constitutes evidence, so that you can maintain your denial-yet you'll leap on the smallest amount of data to "prove" your point. As a *scientist* myself, I have a very good understanding of what amount of data is accepted as statistically significant-you, on the other hand, have *no clue* about statistical significance. "What about the 30 years of statistical cooling between about 1940 and 1970? If that happened to be the period as the base for the '*average* state of affairs', you'd have concluded it was cooling (or at least that it wasn't warming)." There is so much *noise* in that data that its not actually statistically significant-largely because the time series you use marks the end of the solar induced warming of the first half of the 20th century (1900-1945), & the brief cooling that followed it. It also represents the usual cherry-picking I've equally come to expect from the Denialist Cult. If I take 1945-1975, for example, I get a modest warming trend (though, again, not statistically significant). By contrast, if you take 1950-2010 or 1980 to 2010, you get a very statistically significant warming trend. Anyway, why are you talking about 1940-1970? I thought you only trusted satellite data? "But the average used for the standard deviation is from 1979-2000 and not 1979-2010. Did you catch that? The record low extent didn't occur until 2007. These are some of the kinds of issues that can skew the trend analysis when only such a short period of time is available." Oh, that's too hilarious RW1. Yes, 1979-2000, a period in which the majority of the experts believe that ice loss was already underway (& had been for about a decade). Yet all the ice coverage for 2001-2010 has been below even *this* average. You denialists do have an uncanny knack of shooting yourselves in the foot.
  47. A Swift Kick in the Ice
    "Given that the amount of fluctuation from year to year is frequently as much as 0.4 to 0.5 C, I'm hardly shaking in my boots. The last 30 years could be easily wiped out in just a couple years. " Another typical denialist cult argument, RW1. You clearly haven't even got a *clue* how the temperature anomalies work-or the warming trend-or you wouldn't make such a blindingly ignorant comment. In fact there are no 0.4 to 0.5 degree fluctuations in temperatures, as you claim. Average year-to-year fluctuations are more on a scale of 0.05 to 0.2 degrees. Also, the minimum & maximum anomaly in each decade continues to increase. So in the 1980's, the minimum anomaly was +0.05 degrees & the maximum was +0.31 (in 1988 alone)-with the most common maximum being +0.26. In the 1990's, the minimum anomaly was +0.13 degrees, & the maximum was +0.57 degrees (in 1998 alone), with the most common anomaly for the decade being around +0.35. In the 2000's, the minimum anomaly was +0.32 degrees & the maximum was +0.62 degrees-with the next most common anomaly being around +0.55 to +0.6 degrees. You see a *pattern* emerging?
  48. A Swift Kick in the Ice
    Marcus (RE: 125), "In statistical circles, 30 years of data *is* considered sufficient to arrive at a reasonable *average* state of affairs." What statistical circles? I don't think it's nearly enough. I would think at least a 100 years would be needed to get an accurate picture - perhaps even longer. What about the 30 years of statistical cooling between about 1940 and 1970? If that happened to be the period as the base for the '*average* state of affairs', you'd have concluded it was cooling (or at least that it wasn't warming). "Remember that ice loss isn't just below this average, its more than 2 standard deviations below this average. That makes this ice loss *incredibly* unusual & ongoing. Oh, but its not anecdotal evidence from an article in a newspaper, so how could you *possibly* be accurate?" But the average used for the standard deviation is from 1979-2000 and not 1979-2010. Did you catch that? The record low extent didn't occur until 2007. These are some of the kinds of issues that can skew the trend analysis when only such a short period of time is availble.
  49. A Swift Kick in the Ice
    Funny how this thread has come to resemble the Denominator thread... The Yooper
  50. A Swift Kick in the Ice
    Marcus (RE: 124) "Typical straw-man argument-exactly what I expect from a card-carrying denialist. We only have 30-odd years of satellite data but-in spite of its greater accuracy-it does *not* invalidate the decades of direct observation & measurement that occurred in the decades prior to satellite. You just deny the evidence in front of your own eyes, & use the old canard of "30-years is insufficient" argument to cover yourself-because you know there is no real come-back if you refuse to accept other valid data." Sorry, I have a hard time believing non-satellite data on Artic sea ice extents is reliable. You should be a little more skeptical of such data yourself. Yet funny how you denialists will rant, rave & scream that "global warming has stopped" if even a *single* year-or even a single *month* is colder than expected." I don't do this. "Try closer to almost +0.5 degrees of warming in a 30 year period (over 0.16 degrees per decade), which is actually around 3 times faster than the warming we saw in the first half of the 20th century-you know, when solar activity was rising rapidly. This warming we've seen lately has occurred against the backdrop of falling solar activity, & higher than normal volcanic activity (especially over 1990-2010). It's about 10 times as fast as the warming believed to have occurred during the MWP (which saw a total of +0.6 degrees of warming over a span of SIX HUNDRED YEARS). So yep, the fastest warming ever recorded, & without the usual causes to explain even a slower rate of warming." Given that the amount of fluctuation from year to year is frequently as much as 0.4 to 0.5 C, I'm hardly shaking in my boots. The last 30 years could be easily wiped out in just a couple years.

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