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Comments 108551 to 108600:

  1. The Big Picture (2010 version)
    Perhaps we should move this discussion to How sensitive is our climate? We're well off topic here...
    Moderator Response: Yes, everybody, please do.
  2. The Big Picture (2010 version)
    Given that the various empirical climate sensitivity estimates include volcanic aerosols, Milankovitch redistributions, seasonal irradiation, and the 11 year solar cycle, I think there's plenty of data there on different kinds of forcings. Water vapor and clouds act as feedbacks on other forcings; if the temperature of the atmosphere changes, we should see regional feedbacks in a matter of days at most. In fact, given the speed of water vapor feedback, we should see your postulated large negative feedback on a seasonal basis (summer/winter) - and we don't. Unless you have evidence/papers indicating fractal vapor distribution changes over the seasons that induce large negative feedback on seasonal temperature changes??? Regarding glacial estimates and uncertainties, I am much more interested in papers such as Tung 2007; calculating 2.3 to 4.1°C based on the 11-year solar cycle (i.e., what happens when deviating from current conditions), Hoffert 1992, who looked at reconstructions for both colder and warmer periods, est. 2.3 +/- 0.9 °C, and Bender 2010, response to Mount Pinatubo aerosols, 1.7 to 4.1°C. I agree that glacial ice coverage introduces additional effects - hence my preference for estimates that don't include glacial periods. And again, your postulated large negative feedback is not seen.
  3. The Phony War: Lies, Damn Lies and the IPCC
    Ned, it is the IPCC that predicts the 0.2 C per decade rate that should be occurring now. And it is the IPCC that predicts the various warming rates for different 'scenarios'. Science is about predictions of theories and the following observations which reject or modify the theories. It is incorrect to state that all the models show acceleration. In fact, in the IPCC graph, only one scenario indicates even a slight acceleration, that being the A2 (red). The 'middle' scenario, the A1B, indicates a DEceleration of temperature trend. So does the 'most optimistic' scenario, the B1(blue). And all observed temperature trends are at or below the 'most optimistic' scenario!
    Moderator Response: please limit image size to 400. Thank you.
  4. The Phony War: Lies, Damn Lies and the IPCC
    archiesteel, The CRU and GISS trends are at or below the best estimate for the "most optimistic scenario" for the period you prefer. They are below the most optimistic scenario for the subsequent MSU era. And not surprisingly, no I am not "concerned" about the recent warming rates. Why? 1. The same rate occurred in the CRU without modern CO2 forcing ( CRU and HadSST 1.7 K per century from 1910 to 1945 ). So such a 35 year trend is not even a record in the global thermometer era. 2. During the Holocene Climatic Optimum, climate was actually much more extreme: (longer, hotter summers -and- longer colder winters). But this was the period of the founding of human civilization!
  5. The Big Picture (2010 version)
    You can see climate variability during glacial times is huge compared to its present day value. This variability also implies a much higher sensitivity. Therefore paleo climate sensitivity values derived from glacial epochs have to be scaled down considerably to be applicable today.
  6. Billions of Blow Dryers: Some Missing Heat Returns to Haunt Us
    @TimTheToolMan: absence of evidence is not evidence of absence. What the article is about is the fact that the deep ocean *is* warming, which indicates there's lots of room for the "missing heat" to hide, and thus it is erroneous to claim OHC has not increased since 2005.
  7. The Big Picture (2010 version)
    #134 I wrote: "Modeled and empirical evidence indicates that the actual climate sensitivity is ~3°C for a doubling of CO2 or an equivalent radiological forcing." - see How sensitive is our climate? I see. Climate sensitivity is at leas 3°C (Lorius 1990), but not more than 2.3°C (Tung 2007). Fine. The science is settled. Seriously. As I have already mentioned multiple times, not all "forcings" are created equal. They act at different parts of the climate system (soot: snow covered surface, CO2: upper troposphere to stratosphere) and influence different processes (SW absorption vs. LW emission). Sensitivity of average surface temperature can be radically different for such agents, even if their magnitude converted to the common currency of energy flux anomaly happens to be the same. Also, regional distribution of climate response also varies widely depending on the particular kind of forcing applied. With paleoclimatic studies it is a bit more difficult. It is quite easy to see that general climate sensitivity should be higher in a world where permanent continental ice caps reach down to 40N than in our present day setup. Therefore "climate sensitivity" does not only depend on the kind of forcing but also on structural aspects of the climate system, changing themselves slowly over geologic times (as mountain ranges, configuration of continents, oceanic currents, presence or lack of ice sheets, etc.)
  8. Is Greenland losing ice? (psst, the answer is yes, at an accelerating rate)
    I agree with some posting here that the results from Wu et al. should be included. With that said, as Cynicus pointed out @12, nowhere in their paper do Wu et al. speak to the rate of change of loss with time (i.e., acceleration or a slow down), they talk about the mean loss between 2002 and 2008. Wu et al. do confirm recent studies which found that the once thought to be stable EAIS may be losing ice (albeit with large error bars). They also confirm that Alaska Yukon are lost about 100 Gt a year between 2002 and 2008-- that is about as much as the loss from GIS, or as much loss as EAIS and WAIS combined. Also, there is a note of caution required. From a summary of the Wu et al. paper by Bromwich and Nicolas(2010): "However, the revised estimates of glacial isostatic adjustment carry their own uncertainties: they depend strongly on a small number of GPS records that are all located on the ice-sheet margins." So, the jury is still out as someone else here has noted ...in the mean time the data indicate that GIS, WAIS and EAIS continue to lose ice mass, very likely at an accelerating rate.
  9. Is Greenland losing ice? (psst, the answer is yes, at an accelerating rate)
    Here's a screen grab from the paper that suggests the mechanism controlling mass loss for SE Greenland glacier. ( http://i51.tinypic.com/2wqvkab.png ) This got me thinking whether it's sensible to produce a whole Greenland mass loss and then try to attribute this to a single forcing? As Kahn 2010 paper suggests NW Greenland acceleration in mass loss began in 2005. The Murray 2010 paper suggests SE Greenland accelerated early 2000's and then the rate declined late 2000's. I assume acceleration in SW Greenland began in early 2000's but I don't know how it then developed. Let's ignore what's going on in the NE. If we have multiple different processes occuring at different times in different regions of Greenland over the past decade can we lump the results from these different processes into a single whole Greenland ice mass loss and get any real meaning from that? (BTW Murray et al 2010 suggest the above mechanism as the main process controlling mass loss in SE Greenland.)
  10. Is Greenland losing ice? (psst, the answer is yes, at an accelerating rate)
    As part of the Arctic Report Card Hanna, Box and Huybrechts (2008) summarized the mass balance state of the Greenland Ice Sheet. The mass balance has been assessed using multiple measures only one of which is GRACE. Reading this report card will indicate that the bulk of the studies are closer to the Wu et al., (2010) results discussed above. Ten years ago we could not assess the mass balance of the ice sheet. Today we are still developing this skill. As usual it is best to rely on multiple data sets. We have laser altimetry, surface mass balance models and GRACE. A couple of sentences from the aforementioned authors ..." A recent survey concludes that the GrIS is currently losing ~100 Gt yr-1 (Shepherd and Wingham 2007). However, there remains considerable discrepancy among these pioneering observational estimates. " and "Airborne and satellite laser-altimetry data analyses indicate a volume loss of about 60 km3 yr-1 in the 1993/4 - 1998/9 period, that increased to about 80 km3 yr-1 in 1997-2003 (Krabill et al. 2004, Thomas et al. 2006). Various recent analyses of gravimetric (GRACE) satellite data suggest greater mass (volume) losses in the 101-226 Gt yr-1 (111-248 km3 yr-1) range within the recent few years, that is, 2002-2006 (Luthcke et al. 2006, Velicogna and Wahr 2006). " The time periods and methods are not identical but do indicate that the low 100 Gt yr-1 has been a frequent result. It is evident that the loss has not stopped, as the volume losses of Humboldt, Jakobshavns, Petermann and many others continued in 2010
  11. Is Greenland losing ice? (psst, the answer is yes, at an accelerating rate)
    I think a lot of people have been talking about the Wu et al. 2010 paper with respect to these Greenland estimates. A newer paper (Bamber and Riva, 2010) was recently published and included an estimate for both ice sheets. I submitted a comment on the paper asking why the authors chose to go with Van Den Broeke's (2009) estimate rather than the Wu et al (2010) estimate. The Bamber and Riva Paper can be accessed here: http://www.the-cryosphere-discuss.net/4/1593/2010/tcd-4-1593-2010.pdf Their reply is listed here: http://www.the-cryosphere-discuss.net/4/C813/2010/tcd-4-C813-2010.pdf Some highlights of the reply include: "Because a paper is the most recent does not, necessarily, make it the most reliable or "best" estimate." "It is important to realise that they are producing a global solution for GIA and PDMT by finding a least squares minimisation for the GRACE, GPS and modelled OBP data sets. The solution has not been tuned for any one location and the quality of the solution will depend on the quality and spatial density of the data sets that went into it. As far as we can tell, the solution is not constrained to pass through the observations. In Greenland, there are very few GPS site with a sufficiently long record (just 3) that could be used and none in the interior of either Antarctica or Greenland." Bamber and Riva are both very well known glaciologists and Bamber is well-known as being a world leading glaciologist. One of the best, therefore we should take his estimates quite seriously. What I think the take home message is that Wu et al (2010) use a new approach to calculate Greenland mass balance. This approach may become the best approach in the near future when more GPS stations are available (IPY put up a lot) but that currently this approach (although novel and useful) is not accurate enough to be termed the "best" estimate for Greenland Ice Losses. I have identified quite a few issues myself with the Wu et al (2010) paper that are not big but that require maybe some questioning. I think that a lot of people have to watch out how quickly they jump on the bandwagon of a new paper. Funny how well reported the Wu et al (2010) paper was compared to Bamber and Riva (2010) which is newer...
  12. The Big Picture (2010 version)
    BP, Riccardo, KR Excellent discussion gentlemen. This WV-Cloud-CO2 interaction is the nub of the whole AGW hypothesis. I have followed BP's arguments through many months and many threads, and a constant theme is that the WV and ice albedo feedbacks are not as positive as claimed and therefore the 'greenhouse' insulating effect of the atmospheric column is lower. Dr Trenberth puts the WV and ice albedo feedback at about +2.1W/sq.m - would anyone like to update this figure? I don't profess to fully understand how this energy flux number relates to temperature differential across the column or how the 'fractal' nature of clouds as seen from space affects the average IR emitting temperature of the Earth which is quoted at about 255degK. BP's response on the paleo data argument would also be very interesting.
  13. French translation of the Scientific Guide to 'Skeptics Handbook'
    Having recently returned from a trip to the South of France, I would like to make the following comment about this translation : Très bon !
  14. The Big Picture (2010 version)
    Berényi - You missed half of my statement, and a very important half: I wrote: "Modeled and empirical evidence indicates that the actual climate sensitivity is ~3°C for a doubling of CO2 or an equivalent radiological forcing." - see How sensitive is our climate? Not just models, but multiple sets of paleo data and analyses indicate about 3°C climate sensitivity. The empirical evidence shows it quite clearly; we don't have the large negative feedback you are postulating. And as I have stated before, if the evidence contradicts your hypothesis, you need a new hypothesis. Claiming "we can't know, so what about this theory!" is a variation of the Appeal To Complexity; a bad argument.
  15. Is Greenland losing ice? (psst, the answer is yes, at an accelerating rate)
    JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 115, F03026, 15 PP., 2010 doi:10.1029/2009JF001522 Ocean regulation hypothesis for glacier dynamics in southeast Greenland and implications for ice sheet mass changes. T. Murray et al I recommend a read of the above paper if you can get past the paywall. It proposes a slightly more complex process controlling glaciers in SE Greenland. They even dare to suggest re-advancing glaciers in this region in the late 2000's.
  16. 2010 Climate Change Resource Roundup
    I posted a link to a peer-reviewed article about denialism to which Anthony seemed to accept. His problem is with the use of "denier" is in the pejorative sense, where AGW denier is like holocaust denier. Although I usually don't see this connection made, except to show that the underlying psychological reaction to information that goes against one's preferred reality is similar (no racism or attempt to downplay the holocaust). I can see why this is bothersome to Anthony, but I doubt this is what John Bruno was attempting. The awkward thing is that Watts' blog is full of the examples shown in the article I posted.
  17. Billions of Blow Dryers: Some Missing Heat Returns to Haunt Us
    ...now zoom in to that graph to see what the data really shows by joining the two known points. And that is a much lower rate of temperature increase over the period. This paper says trends are "evidence". They're just not. Only artual measuments are evidence and they simply dont have enough to say anything about 2005-2010
  18. Billions of Blow Dryers: Some Missing Heat Returns to Haunt Us
    Nonsense. Look at the one data point that has two readings in the period of interest. P18. This is the one that they choose to graph in figure 3. You can see what they "want" to show by the way they've trended it back to the early to mid 90's. No zoom in to that graph to see wha
  19. Is Greenland losing ice? (psst, the answer is yes, at an accelerating rate)
    JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 115, F03026, 15 PP., 2010 doi:10.1029/2009JF001522 Ocean regulation hypothesis for glacier dynamics in southeast Greenland and implications for ice sheet mass changes Ocean regulation hypothesis for glacier dynamics in southeast Greenland and implications for ice sheet mass changes T. Murray
  20. Billions of Blow Dryers: Some Missing Heat Returns to Haunt Us
    Posted by doug_bostrom on Thursday, 23 September, 2010 at 04:40 AM in amusingly prosaic terms: the newly located reservoir of energy is akin to what would be liberated by loading every man, woman and child on Earth with five 1,400 watt hairdryers each and running those appliances continuously for the 20 year interval between measurements That's about 8.4×1012 W. As surface of oceans is 3.6×1014 m2, this newly discovered heat flux is 23 mW/m2. Average geothermal heat flux at ocean bottom, which is usually considered negligible, is four times that much. In other words it would take about twenty thousand years for mankind to increase ocean temperatures by 1°C using hairdryers. Amusing, indeed.
  21. The Big Picture (2010 version)
    Berényi Péter, did I say that WV is not a gas? Did I say it does not absorb IR? Did I say that its distribution is not related to the possible phase changes in the atmosphere? No, obvisously, I was pointing out the opposite. I also warned to treat the various phase separately and that the liquid easily absorbs thermal IR throughout the relevant frequency range. The liquid phase, I'm sure you'll agree, is one the larger uncertainty in many respects and needs a much larger point of view. Finally, no one I'm aware of has calculated the WV effect as a well mixed gas. That local inhomogeneities significantly affect the estimates has yet to be proven.
  22. Is Greenland losing ice? (psst, the answer is yes, at an accelerating rate)
    Do the majority of people really care if Greenland is losing a little ice and the oceans are rising a few centimeters and it's getting a little warmer? The people I know have air conditioners for when it's too hot, and more days for the beach, golf, and tennis than before. I've sent them links to Skeptical Science, but they've trashed them. They don't understand all that technical stuff. They don't care whether this or that paper has errors or not, they just know from watching TV, reading magazines and newspapers, and experiencing the weather, that global warming research has been inconclusive. Skeptical Science would have more impact if the topics and discussions swung around to introducing and describing real-world environmental and economic scenarios that will unfold in the wake of climate changes. Write scripts for those disaster movies, but make them realistic. Global warming is not going to bury the Statue of Liberty or send tidal waves over cities. Turn all those meaningless warnings written in technical papers into realistic scenarios the average Joe can understand and interpret, and maybe he will start to notice and reason. Otherwise he will continue along the paths set by big business and the oil industry.
  23. Billions of Blow Dryers: Some Missing Heat Returns to Haunt Us
    TimTheToolMan, it shows that the graphs on which the 'no OHC increase from 2005 to 2010' claim are based are wrong. Those graphs would only be correct if there was minimal warming of the deep oceans on a decadal time scale. However, this study proves that is NOT the case. Portions of the ocean below 4000 m have warmed significantly. Thus, the claim that there has been no increase since 2005 is based on data we now KNOW to be erroneous... and the claim is now PROVEN nonsense rather than merely the OBVIOUS nonsense that it was before. No, we do not have a complete time series for every cubic kilometer of the oceans and thus still cannot produce an accurate OHC measurement graph. But we now have conclusive proof that the previous graphs were leaving out a significant amount of heat. Which, of course, was obvious to begin with since we knew that observed sea level rise matched the heat which we knew SHOULD have been generated by observed radiation fluxes... but the measured ocean heat buildup was inconsistent with both.
  24. 2010 Climate Change Resource Roundup
    I know what you mean dorlomin, but it really is a matter of the one way thin skin. Happy to brand people as watermelons or eco-fascists or worse. Shocked horror pulling the skirts away if anyone mumbles the 'd.....' word in the next street.
  25. Is Greenland losing ice? (psst, the answer is yes, at an accelerating rate)
    @Ned, #11 "the black line is from Velicogna, some of the green triangles are from Luthcke, and the other green triangles are from ..." Thanks for the info, but that's not my question. The various green triangles have relatively small vertical black lines, drawn in the manner which is usually used to denote error bands. These bands are relatively small, indicating that the various authors of these estimates believe that they have a relatively precise, accurate measurement. Unfortunately, it appears that these multiple, relatively precise measurements are inconsistent with each other. Am I interpreting the graph incorrectly? For example, if two simultaneous measurements of some parameter are expressed as -220+/-10 and -90+/-10 is there not an obvious underestimation of the error of the measurements?
  26. The Asymmetric War on Climate Change: No Cause for Alarmism?
    No Roger, I'm very much afraid the 'intelligent' thinking is I'm all right, Jack. Someone else can clean up my mess. Attitude much like the 14 yr old kid in the bathroom and the scattered wet towels. More money, more power, more mess. Same attitude.
  27. Billions of Blow Dryers: Some Missing Heat Returns to Haunt Us
    I dont think you understand the problem CBDunkerson. The claim is that there is OHC increase between 2005 and 2010 and the evidence is not from measurement but from extrapolation from a time when there WAS measured warming. The research doesn't ACTUALLY show warming at all. It assumes it.
  28. Is Greenland losing ice? (psst, the answer is yes, at an accelerating rate)
    #8 Falcon, there is a slight difference between "on average -101 Gt/yr" and "-101 Gt/yr". The former allows for acceleration and the latter doesn't. From the Geoscience publication: "[..] for the period spanning April 2002 to December 2008, Wu and colleagues find an average annual ice-mass change of −104 ± 23 Gt yr−1 for Greenland and −64 ± 32 Gt yr−1 for West Antarctica."
  29. The Asymmetric War on Climate Change: No Cause for Alarmism?
    RSVP@44: The people referred to in Roger@43 use their intelligence, but for their own personal gain. The news media is controlled by oil companies and big businesses, and the news media controls conservative actions. Climate change mitigation will cost oil companies and big businesses "trillions of dollars," and no one wants to see their taxes and prices increased to pay for that. Even though several recent surveys have shown that the majority of people in the United States and the world believe global warming is serious and something should be done about it, very little is being done. I guess the intelligent thinking is, "God made the world, let Him fix it."
  30. Is Greenland losing ice? (psst, the answer is yes, at an accelerating rate)
    Charlie A: As you might have noticed from the previous comments in this thread, there has been some disagreement among different groups processing the GRACE data (though all show declining mass balance). The different green diamonds (and the black line, too) come from different groups working with the same GRACE data. I don't have the Jiang paper in front of me, but IIRC the black line is from Velicogna, some of the green triangles are from Luthcke, and the other green triangles are from ... someone else I don't remember.
  31. Billions of Blow Dryers: Some Missing Heat Returns to Haunt Us
    TimTheToolMan, whether you find it convincing or not is irrelevant. The research shows that there has been warming of the deep oceans. This disproves the (frankly ridiculous to begin with) claims that previous OHC graphs were capturing all ocean warming. We have found significant warming which was not accounted for in previous results... ergo we now know that some of the "missing OHC" is to be found in deep ocean warming. Precisely where everyone who isn't completely ridiculous thought it must be.
  32. Billions of Blow Dryers: Some Missing Heat Returns to Haunt Us
    How does this paper answer the question of missing OHC between 2005 and 2010 when fewer than half the stations have readings during that period? And almost all of those have but a single reading? What they've done is extrapolated constant warming over the 20-30 year period of the data beyond that which it was actually measured. Very unconvincing.
  33. The Big Picture (2010 version)
    #130 Riccardo at 20:33 PM on 28 September, 2010 you treatment assume a condensed phase behaviour No, it does not. Water vapor is a gas, transparent in the visible portion of the spectrum (with some absorption lines in the near IR though) and lots of absorption in thermal IR, even in the so called "atmospheric window" between 8 and 14 μm (see the slightly mysterious "water vapor continuum"). In its gas (a.k.a. "vapor") phase water is a perfectly legitimate GHG quite independent of its condensed phase ("cloud" or "fog") behavior. It is its atmospheric distribution which is not independent of the fact it can have multiple (gas, fluid, solid) phases under ordinary meteorologic conditions. As soon as a parcel of air gets saturated (due to adiabatic cooling) and precipitation is formed, the air exiting at cloud top is left with very low specific humidity (and high potential temperature). As it enters a cloud free region, it starts to cool radiatively to space, descending slowly. In this process it can get turbulently mixed with other air parcels with different specific humidities, but due to multi-scale properties of turbulent 3D flows this mixing seldom have the chance to complete its job, that is, before homogenization could get down to the molecular level, another saturation episode occurs, resetting the clock once again. Therefore water vapor (gas phase) distribution is very far from being uniform most of the time and under most meteorologic conditions, even under clear skies. So average specific humidity alone can never tell the whole story of its radiative properties, much less column integrated water content. Humidity distribution above the boundary layer is pretty much decoupled from surface temperatures below, reflecting history of air masses involved.
  34. Is Greenland losing ice? (psst, the answer is yes, at an accelerating rate)
    Can someone explain the meaning of the error bars in the graph. The various, almost simultaneous, estimates of mass loss by the Grace system have relatively small error bars, but many of them are non-overlapping. It seems that the error bars reflect only statistical sampling error and grossly underestimate the true potential error of the measurements.
  35. The Big Picture (2010 version)
    Berényi Péter, to add to my previous comment, absorption coefficient of water is relatively high throughout the infrared and all light is fully absorbed in a few tens of microns. Just a few droplets in the water column will suffice to block all the outgoing radiation.
  36. The Asymmetric War on Climate Change: No Cause for Alarmism?
    Roger A. Wehage #43 God gave us our intelligence. It's up to us to use it.
  37. 2010 Climate Change Resource Roundup
    They took exception to your use of the word 'denier'. I would suggest, given the oeuvre of Johns blog, that people writing the posts should be hypersensitive to the sensibilities of the 'other side of the mirror' so as not to afford them opertunities to ignore the content and focus on the style.
  38. A detailed look at galactic cosmic rays
    Argus (d) Fortunately rather than being ignorant and subject to argument by arbitrary assertion, we can use facts to check our understanding of the world.
  39. The Big Picture (2010 version)
    Berényi Péter you treatment assume a condensed phase behaviour. As I said before, unless you call water vapour micron size liquid droplets it does not apply. Probably it's just a misunderstanding, you include clouds under the term water vapour. In this case, I agree with you, distribution does matter. By the way, it's included in any model.
  40. Is Greenland losing ice? (psst, the answer is yes, at an accelerating rate)
    #7 cynicus I hadn't seen Luthcke et al 2007, thanks for that. In my view it reinforces the need to point out and quantify the uncertainties rather than unintentionally marginalise them.
  41. Is Greenland losing ice? (psst, the answer is yes, at an accelerating rate)
    Whether the rate of loss is increasing is an important issue. Don't forget this article claims that "that these losses have drastically increased since the year 2000" Velicogna et al (2009) concluded that the mass loss increased from 137 Gt/yr in 2002–2003 to 286 Gt/yr in 2007–2009. However, Wu et al (2010) cite mass losses between 2002 and 2008 of 104 +/- 23 Gt/yr which would suggest that there is little evidence in the data that the rate of melt has been increasing. I suggest it won't be long before someone jumps all over the way this article has summarized the issue.
  42. Is Greenland losing ice? (psst, the answer is yes, at an accelerating rate)
    #3 Falcon, we reference the same paper but we disagree in details: 1. I have not found any reference that the paper disputes acceleration of the losses. 2. The paper does not "less then half" all other GRACE-based estimates: Luthcke et al 2007 used GRACE data and applied a method with greater spatial and temporal resolution to come up with -101 Gt/yr between 2003 and 2005 which seems to correlate perfectly with the Wu et al paper. Perhaps Luthcke has found a way around the isostatic rebound and mass redistribution using the greater spatial and temporal resolution. It sounds plausible to me but I'm not qualified to judge that.
  43. 2010 Climate Change Resource Roundup
    I read (and re-read) this post but I don't understand what has Anthony and the "skeptic" community so upset about it. It seems pretty bland and light-hearted; certainly not a hit piece. Maybe the promotion of fact-based sources for information about climate change (many of which are run by scientists) is what is so threatening? The post itself obviously isn't peer reviewed (nor is any post on any blog) but most of the science covered in these blogs/outlets certainly is. The arguments and evidence in every one of these sources is based on extensive peer-reveiwed science and the citations/sources are very clear. Yes, I am a different John, and to be totally clear on who I am and what my scientific credentials are, where my funding comes from, etc., go here
  44. Is Greenland losing ice? (psst, the answer is yes, at an accelerating rate)
    Too early to say really. The writers of the earlier papers based on GRACE data believe they got the isostatic rebound correct. A new paper by Wu suggests it is a larger factor. Frankly, the jury is still out. One issue with the Wu analysis is that if significantly less ice has melted than previously thought then we have a bigger problem explaining the observed sea level rise. Any decrease in ice loss must be made up by increased expansion due to heating. In any case, given that they confirm the increasing rate of ice loss the magnitude isn't really a major issue... the rate has been doubling every few years, so if the current rate is half what had been thought then we'd still be back up to the previously estimated rate within the decade. The long term difference is negligible.
  45. Is Greenland losing ice? (psst, the answer is yes, at an accelerating rate)
    I think it should be noted that the mass balance estimates based on GRACE might be a bit exaggerated in some literature (Velicogna et al 2009 and Chen et al 2009). The linked paper argues that redistribution of the mass of the ice loss around the globe and isostatic rebound due to unloading is not fully accounted for in a number of papers which use GRACE data. However, while this papers disputes the magnitude of the loss in some literature, it does not dispute the acceleration of the loss. (A more elaborate summary is here.)
  46. Is Greenland losing ice? (psst, the answer is yes, at an accelerating rate)
    The graphs probably need to be updated, incorrect accounting for post glacial rebound is probably doubling the figures given there!
  47. We're coming out of the Little Ice Age
    cruzn246 #36: As usual, you seem to be basing your conclusions on fiction. "The carbon data is all over the place clearly showing the Little ice age big time, but hockey stick Mann claims it wasn't a NA event. Please." Mann doesn't say that the LIA was a non event. It is very clearly evident in the Mann 2008 reconstruction; "WHY? Are they afraid to show what happened with carbon 14 after that? I would say yes." Congratulations, your official wacky conspiracy theorist tin foil hat is in the mail. Carbon 14 ratio was a reasonable proxy for solar irradiance prior to the point that we started putting tons of fossil carbon into the atmosphere and releasing bursts of radiation with atomic explosions. Of course, we've been able to measure solar irradiance directly for decades so we don't need proxies any more. We've been in a pronounced solar minimum for a few decades now... while temperatures have been going through the roof. "I know this is not a carbon 14 measure, but this closely follows the same of pattern carbon 14 readings." Ummm... what? They aren't even close. Total atmospheric carbon levels barely changed at all between 1000 AD and 1800 AD while Carbon 14 ratio was going up and down like a roller coaster along with TSI. Since then total atmospheric CO2 has risen at a steadily increasing rate while Carbon 14 has continued to roller coaster.
  48. The Asymmetric War on Climate Change: No Cause for Alarmism?
    The world needs fixing fast, and God isn't helping.
  49. Is Greenland losing ice? (psst, the answer is yes, at an accelerating rate)
    The article fails to mention that a new paper, Wu et al. (2010), has concluded that that losses have not in fact accelerated as claimed. Although the ice-sheets are losing mass, the losses estimated by the authors represent less than half of the other GRACE-based estimates, which undermine the collusions the four papers cited in Wray's article. Wu et al. conclude that "a significant revision of the present estimates of glacial isostatic adjustments and land-ocean water exchange is required". Reference: Wu et al (2010) "Simultaneous estimation of global present-day water transport and glacial isostatic adjustment" Nature Geoscience 3, 642 - 646 (2010)doi:10.1038/ngeo938 (Link to www.nature.com)
  50. The Big Picture (2010 version)
    archiesteel #125 Ned and I did some forensics on BP's failed statistical analysis (i.e. would get him a fail grade as a first year university assignment) in this thread. We determined that the analysis suggested that if his estimate of the urban heat island effect was reasonable (and it's far more likely to be an overestimate - but we can't say if it is or by how much because he hasn't released his methodology) then his estimate for climate sensitivity is bang-on 3 degrees Celsius once corrected for the urban heat island effect. Which is entirely consistent with the mainstream climate science estimate. BP's current tangent appears to be a variant of the 'models are inaccurate' argument. It seems to me to be without merit as it uses the "if we can't know everything then we know nothing fallacy.

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