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Comments 72251 to 72300:

  1. Correction to the True Cost of Coal Power - MMN11
    @keithpickering At great risk of running off topic (from causes to remedies), the obvious immediate risk of your proposal is that applying such a tax unilaterally within one country would (be seen to) put products manufactured in that country at a disadvantage compared to those produced in a country without such a tax. For imports, one can imagine this being remedied by an import duty based on the ratio of fuel types consumed in the producing country. However exporters would still (be seen to) be at a disadvantage. What, in outline, would be your solution?
  2. Models are unreliable
    Thanks for the further links, DB. I've now located a paper which discusses the discrepancy in time-averaged global mean temperatures between the different GCM's: An Overview of Results from the Coupled Model Intercomparison Project (CMIP) The paper states: "Both flux-adjusted and non-flux-adjusted models produce a surprising variety of time-averaged global mean temperatures, from less than 12°C to over 16°C. Perhaps this quantity has not been the subject of as much attention as it deserves in model development and evaluation." However, given that we're dealing with energy flux here, the appropriate unit is surely the Kelvin. In this context, all of the models get within 2K of the actual global mean, which appears to be around 287K - that's within 0.7%!! I'd say that's pretty remarkable given all the various features which are incorporated into the models. Indeed, if they model the response to greenhouse gases anything like that well I'm sure the scientists will be delighted! Paul
  3. Anne-Marie Blackburn at 04:29 AM on 17 October 2011
    Review of Rough Winds: Extreme Weather and Climate Change by James Powell
    Norman You are constantly cherry-picking areas you claim have seen no changes. But what about those places that have already seen changes in extreme event frequency and/or intensity? How do you explain those? And how do you explain that rising temperatures and water vapour levels have no impact on extreme weather? The US Global Change Research Program's report on National Climate Change highlights some of the changes that have already happened. How do you explain these without taking into account climate change? What mechanisms are responsible? How are the effects of rising temperatures and water vapour levels, and changing atmospheric circulation, for example, nullified?
  4. Review of Rough Winds: Extreme Weather and Climate Change by James Powell
    228, Norman, Thank you for being the poster child for denial
    "...but in Nebraska there is no evidence..."
    Everyone can relax because in your opinion Nebraska looks fine.
  5. Review of Rough Winds: Extreme Weather and Climate Change by James Powell
    muoncounter @222 You have suggested looking farther then out ones own window to get a sense if the climate is changing for the worse, but in Nebraska there is no evidence of this taking place. I do have good memory of several extreme weather events that have taken place in my local area and there is no evidence of an increasing number. Last 10 years of Corn Harvests in Nebraska have been very good. And 2011 looks just as good or better. Record Corn harvest expected for Nebraska in 2011.
  6. Ocean Heat Poised To Come Back And Haunt Us?
    RobP#18: "Except for a great many skeptics you mean" Please take both parts of my sentence as a whole: 'Skeptics' blindly make such claims because of their gross oversimplifications. "Statistical significance is a whole lot less intuitive to a public audience, ... " The discussion just concluded was very clear on this issue, both in Dana's introduction and subsequent comments.
    it's entirely possible that over such a short timeframe, short-term noise such as ENSO and solar cycles may have masked the continuing long-term global warming trend."

    Quoting resident statistical significance guru Dikran M,

    if you want to suggest there is any scientific interest in this hypothesis, then you need to show that the hypothesis test has meaningful power. So my question is, what is the statistical power of the test?

    Conclusions drawn from short periods should be treated very carefully; that's neither complicated nor anti-intuitive. " ... than is examining why we have these hiatus periods." Here is Tom Curtis the last time this came up:

    there has been ongoing global warming in the period 2001-1010 at a rate similar to the preceding two decades; There may have been a slight reduction in the rate of warming in the last three years due primarily to an unusually for the 2000's cold year in 2008, although an unusually warm year for any other decade of the instrumental record;

    That post dealt with the 'hiatus' via Kaufmann et al 2011, in terms of the slight changes in radiative forcing. Quoting,

    the cooling effect of sulfates nearly cancels out the warming effect of greenhouse gases, allowing natural processes to control the climate.... the small drop in sunlight reaching the Earth as part of the natural solar cycle, ... leads to a much smaller push in the direction of warming.

    Those are legitimate reasons why radiative forcing would briefly decrease (as illustrated in Figure 2), taking global temperatures on ‘hiatus.’ Are we now saying that explanation was insufficient? Because Meehl’s heat storage model requires no such drop in energy flux, as shown by the twin bars in left hand of Figure 3 here). So I’m with Peru on this: let’s save this model for some hiatus to come. "let's just say we disagree and leave it at that." Now that phrase is awfully familiar. I'm arguing neither the model nor the data, but let us at least have some consistency in how we reconcile the two.

  7. Ocean Heat Poised To Come Back And Haunt Us?
    Thank you Rob, great article. I have been struggling to understand when and how the heat being absorbed by the ocean - especially the deep ocean - will be "given back". I have a question about two alternate scenarios to those depicted in your wonderful graphics (Figs 1 and 2); how likely do you/the literature think they are. The first being an increase in the amplitude of the cycles (eg, more "severe" ENSO cycles) and in the second, the cycle gets washed out by the background temp rise and "disappear". A lot of scientists that don't specialize on climate change still assume ENSO will become more severe and when I was working at CSIRO last year, I heard a lot of talk about their models suggestion ENSO would be soon washed out and sort fo fade away. Thoughts? And how did you make those figures?! Cheers, JB
  8. Ocean Heat Poised To Come Back And Haunt Us?
    Thanks for the explanation for my question in comment #7. The increased or decreased evapotranspiration from ENSO does make sense in changing the temperatures in the tropics and subtropics, but the cooling and warming of El Nino and La Nina seem to reach the high latitudes too. For example, the winter of 2006-07(an El Nino winter) was the warmest winter on record by far in the northern hemisphere, with the warmth most pronounced in the high latitudes. A year later, the winter of 2007-08(a La Nina winter) was one of the coldest northern hemisphere winters of the decade, with the cooling most pronounced in the mid to high latitudes. Since EL Nino and La Nina occur in the tropics, one would expect their cooling effects to restricted to the tropics and subtropics. But they seem to have a strong influence on temperatures in the mid to high latitudes. Is there an explanation of how warming or cooling of equatorial pacific waters can cause warming or cooling, say in the arctic, northern Eurasia, and North America?
  9. Antarctica is too cold to lose ice
    Based on the post, I get the impression that the causal connection between (CO2 driven) rising global temperature and the decline in Antarctic land ice can be summerazised as follows: 1) CO2 causes an increase in surface air temperature 2) From 1) an increase in ocean temperatures follow 3) The warmer ocean causes ice shelves at the terminus of the glaciers to thinnen, making them lighter and thus given less resistance to the ice flow of the glaciers 4) From 3) an increase in glacier velocity occurs and this removes more ice from the accumulation zone, the result being that the glacier shrinks. Is this an accurate summary of how more CO2 is leading to less antarctic land ice? Suggestions and corrections are more than welcome
  10. Correction to the True Cost of Coal Power - MMN11
    I should have said "How some economists". Unfortunately, many of those economists get headlines in the Wall Street Journal and on Fox news regularly. Assessments from the other side are not publicised to the same extent in the main stream media. If the weather of the past 18 months turns out to be the new normal, they will have devalued all of our lives.
  11. Review of Rough Winds: Extreme Weather and Climate Change by James Powell
    skywatcher @226, What my data shows is that it resembles the graph of extreme one day preciptiaton events that the Figure 16 of the Peterson (2008) graph shows (I don't have the ability at this time to post this graph, it does not have the normal link of other graphs or I would like to post it here). In the data I compiled for Oklahoma City, there is a large increase in extreme one day precipitation amounts (both in number and preciptiation amount) in the 1980's and then it drops off in the 1990's and 2000's. Very similar pattern to the Figure 16 graph of the Peterson (2008) paper. He has a trend line that shows it going up but nothing comes close to the peak in the 1980's.
  12. Dikran Marsupial at 19:47 PM on 16 October 2011
    Continued Lower Atmosphere Warming
    Ger The models are dynamical systems, forcings can be applied to them to simulate both the transient and equilibrium responses. For example of analysis of transient response, IIRC there were several papers on modelling the transient response to the Pinatubo eruption. However discussions of the workings of the models are clearly off-topic for this thread, as they are not involved in assessing whether there has been a statistically significant change in the observed trends. So please take the discussion to a more appropriate thread, such as "the models are unreliable".
  13. Continued Lower Atmosphere Warming
    #57, Spaerica, did glance over the document, and yes most if not all are equilibrium models on which perturbation is applied to find out how well behaved those are. Equilibrium sensitivity etcetera. But is cloud forming, mainly shape etc. governed by a equilibrium model? Is the change of coastal areas and changing flow patterns governed by an equilibrium model? Are volcano eruptions, earthquakes etc governed by some equilibrium model? One can consider all those as governing conditions to be input to an equilibrium model, but those boundary conditions are rather unpredictable. Clouds, coastal lines etc can be modelled into by chaotic models perhaps. No idea if that will obey normal statistics. Volcanoes etc. are related with radio-active decay so one can assume those will follow a Poison distribution.So to say: any one can pick a starting date, before or after a large change in one of these parameters and "proof" or "disprove" a statement based on the statistics of an equilibrium model. One can have endless debates on the time period to chose whether not to include, exclude those singularities.
  14. Ocean Heat Poised To Come Back And Haunt Us?
    Muon - "No one suggests warming is monotonic" Except for a great many skeptics you mean. Statistical significance is a whole lot less intuitive to a public audience, than is examining why we have these hiatus periods. No matter, let's just say we disagree and leave it at that. There are a whole bunch of climate scientists who have looked at this hiatus period, and have papers awaiting publication. So I'll be writing more about it in the future.
  15. Ocean Heat Poised To Come Back And Haunt Us?
    Rob P, No one suggests warming is monotonic without making gross oversimplifications. But as many have said, its a noisy dataset; analysis of short period variation is a messy business at best.
  16. Review of Rough Winds: Extreme Weather and Climate Change by James Powell
    You are absolutely kidding me, Norman. You're saying that one city does not show a trend, therefore we can't be sure there's a trend. Peterson08 analysed thousands of stations across North America, the overall trend in temperature and precipitation extremes is very clear, as shown by their conclusions. That you continue to try and dismiss a published quantitative analysis of extremes at thousands of stations by discussing a single station is utterly ridiculous.
  17. Ocean Heat Poised To Come Back And Haunt Us?
    Muon - I see little point in pretending a short-term hiatus doesn't exist, just because the long-term (and statistically significant) trend is one of warming. Why pretend warming is monotonic?
  18. keithpickering at 15:01 PM on 16 October 2011
    Correction to the True Cost of Coal Power - MMN11
    The important point is that even using the most conservative estimates, the price of coal is artificially low by a factor of ~2. Correcting this imbalance via a pigovian tax would put renewables on a level playing field.
  19. Ocean Heat Poised To Come Back And Haunt Us?
    Rob P#14: "why the climate varies on short timescales, the up-and-down wiggles" Didn't we just finish wrangling over how those wiggles weren't statistically significant? And take a well-known researcher to task for statements such as "The lower tropospheric global annual average temperature trend (TLT) from 2002 until now cannot distinguished from a zero trend." ...and the trends during this time period are different than the trends earlier in the time period."? Why now are we making very similar sounding statements? "we may currently be in one of these decade-long hiatus periods."
  20. Ocean Heat Poised To Come Back And Haunt Us?
    Barry @10 - I'm working my way through a few papers. This one mght be of interest to you, given your questions: The passive and active nature of ocean heat uptake in idealized climate change experiments - Xie & Vallis (2011) Jsquared @11 - Yes. Plot the data and let us know what you find. Also see Sutton & Roemmich (2011). From the abstract: "Key Points: -The southern ocean dominates decadal global heat content change -Steric contributions below 1500 m are significant and increase towards the south -Simple spatial averaging of WOCE data does not resolve decadal signals" I have copy of the full paper, but I can't remember where I got it from - so can't provide a link. From Peru @13 - you're not the first "warmist" to get hung up on that. I am not referring to long-term trends - yes, we know the Earth is warming, but short-term periods of little or no warming are clearly evident in the observational record. We are looking at why the climate varies on short timescales, the up-and-down wiggles, rather than following a monotonic (straight line) trend. Interesting that the NINO 3.4 index, that you link to, shows a La Nina-like trend since about 2005 (not that this wasn't obvious).
  21. Review of Rough Winds: Extreme Weather and Climate Change by James Powell
    Normna, this has now been going on since comment 15. We're up to 225. 85 of those are yours... more than 30%. They all say the exact same thing, over and over. "Look, look, I found another extreme weather event. Here's another anecdote! Another headline! Another thingy." You have littered this thread with 85 comments pointing out that there has been extreme weather in the past, and so without any other metric than squinting one eye and saying "looks the same to me" you are trying to argue that nothing is wrong, nothing to see, everyone please move along. After 85 of 225 comments it has become very tiresome.
  22. Review of Rough Winds: Extreme Weather and Climate Change by James Powell
    Norman, is that seriously the best you can come up with? That there were some prior events considered 'extreme' is not news to you, me, James Powell or anyone else. Additionally, cherry-picked news articles can hardly be considered credible enough to faithfully place weather events into their proper climatological context (usually kinda turns the readers off...). I'm sure the newspapers from Russia, Pakistan or other places would have been suitably apocalyptic in their prognosis of the relevant extreme events! What is more interesting is when data is placed into a climatological context, such as Peterson et al, or many other papers including Rosenzweig (outdated with regard to recent extremes by virtue of being published in 2001, but hardly supporting your case anyway). By the way, in Peterson et al fig 16, the smoothed line is most likely a moving average or other smoothing function so that you can see the trend over the noise. Is that the worst criticism you have of that paper, seriously? I'll echo michael sweet's request at #223.
  23. Visual depictions of Sea Level Rise
    adelady, thank you ... I'll have to think about the explanation.
  24. Ocean Heat Poised To Come Back And Haunt Us?
    Ummm, this paper shows how a hiatus in global warming can be totally consistent to climate models... ...but I seriously doubt that the 2000s were a hiatus decade, because: 1)Temperatures do not flattened: 2) As is evident in this NINO 3.4 timeseries, ENSO was either neutral or moderate El Niño for most of past decade. The only significant La Niñas were in 2007-2008 and 2010-2011. This is consistent with the previous graph, that shows continuing warming except for a small hiatus in 2008-2009. Certainly a 2-year cooling or flattening is not a warming hiatus decade, is just a minor yearly fluctuaction. The warming pattern is different that the pattern of figure 4: Showing strong warming in the Arctic, unlike figure 4, that shows strong cooling. So is an interesting article, but it could explain some possible warming hiatus decade in the future, not in the present.
  25. Ocean Heat Poised To Come Back And Haunt Us?
    Re #1. Roughly decadal or perhaps roughly 11 years? http://www.woodfortrees.org/plot/sidc-ssn/from:1960 It is perhaps coincidence that the period where this whole haitus thingy starts (~2002) happens to be around the maximum of solar cycle 23, since which we've seen a significant drop to the solar minimum of 2009.
  26. Correction to the True Cost of Coal Power - MMN11
    Not. all. economists, Michael.
  27. Review of Rough Winds: Extreme Weather and Climate Change by James Powell
    Norman, Your list includes many newspaper headlines. I recall last fall when deniers trumpeted a headline stating England was having the coldest winter in 350 years. It did not pan out that way. Dr. Masters has researched his list and when he says it was the worst flood in Pakistan in 500 years that is believable. The newspaper headlines you quote are not vetted and not believable. Please provide a peer reviewed list of disasters. I will note that last year there were 19 countries with all time highest temperatures and none with all time lows. How does that list count for extreme weather? Top that, if you can.
  28. Review of Rough Winds: Extreme Weather and Climate Change by James Powell
    Norman#219: Nice article you've cited: Human activities are causing the augmentation of the natural atmospheric greenhouse effect. Future climate models (which should not be accepted uncritically) predict that anthropogenic forcing will bring about changes in the magnitude and frequency of all key components and natural cycles of the climate system. Climate change will gradually (and, at some point, maybe even abruptly) affect regional and global food production. Warming temperatures and a greater incidence and intensity of extreme weather events may lead to significant reductions in crop yields. --emphasis added Given that this was in 2001, perhaps those projections are coming home to roost. Oops, that was a short compilation of news events.
  29. Review of Rough Winds: Extreme Weather and Climate Change by James Powell
    Daniel Bailey @220 I am not actually allied to the c3 website and I do not agree with their thoughts on Skeptical Science. I like this web site and it contains a vast amount of useful information. I like the strict moderation to keep things on topic. I just saw the list of items on this page and clicked on several to see they were newpaper items. I do not know how else one can determine extreme weather events since they do not always leave evidence that can be analyzed later. I do not want to disappoint and will steer clear of c3 or other type blogs for gathering evidence of the point I am trying to make. That weather may not be getting more extreme as the globe warms.
  30. Ocean Heat Poised To Come Back And Haunt Us?
    Rob Painting @#6 The NODC datasets for ocean heat content to 700m and to 2000m are divided up into contributions for the northern and southern hemispheres. They are at ftp://ftp.nodc.noaa.gov/pub/data.nodc/woa/DATA_ANALYSIS/3M_HEAT_CONTENT/DATA/basin/yearly/h22-w0-2000m.dat and h22-w0-700m.dat. Shouldn't they also show that the heating of the deep ocean is more pronounced in the southern hemisphere? I haven't plotted those data, and I don't have any feeling for what the coverage of the measurement grid is in the lower southern ocean.
  31. Review of Rough Winds: Extreme Weather and Climate Change by James Powell
    To tack onto muoncounter's able comment above: I would not trust any information from a site such as c3 (given its history) in any fashion, to the point of even checking what the time of day was compared to that shown on the website. No compilation of news events, no matter how lengthy, should be relied upon with any form of scientific accuracy. There is simply no context to base any kind of assessment. It is simply a cacophony of anecdotal events in tabular form, listed with the presumption by the reader that it is not only complete but accurate as well. At best, one may consider it interesting in the same sense that one finds supermarket tabloids interesting. Honestly, it is difficult to even know how to respond to you Norman, without it sounding cross. You continually cherry-pick, use anecdotal references interchangeably with scientific ones and preferentially cite denialist websites preferentially over scientific ones. This latest site you ally yourself with has this post:
    "SkepticalScience.com: The 'SS' Global Warming Propaganda & Lie Machine Exposed - Fundamentally Evil"
    Seriously? Since you, by extension/virtue of your reliance upon c3, maintain that Skeptical Science is "Fundamentally Evil", then why are you here? I, for one, no longer believe your protestations of 'just looking for the truth' (paraphrased). It can no longer be construed as innocent mistake your predilection for frequenting & citing such websites as c3. Indeed, I am personally quite offended by this most recent tack you have taken. It was a mis-step; you have over-played your hand. And I am very disappointed.
  32. Correction to the True Cost of Coal Power - MMN11
    It is amazing how economists wil devalue the lives of our children (and ourselves if you are less that 60).
  33. Review of Rough Winds: Extreme Weather and Climate Change by James Powell
    Daniel Bailey, Here is a link to a peer-reviewed article that shows similar patterns to the c3 website. Look at Table 1 of the link. Severe droughts and severe floods from 1977 to 1998. Many samples of such events taking place. It does not seem to be as alarming as James Powell feels it is. Peer Reviewed article with list of weather extremes.
  34. Ocean Heat Poised To Come Back And Haunt Us?
    I am still curious about the physical systems that draw warmth down to the depths. As per my question a couple of weeks ago, how, when the physical processes are so little known, are we able to ascertain mixing rates in order to determine, for example, that oceanic thermal lag takes about 30 - 40 years to reach equilibrium with changes in forcing (Equilibrium Climate Sensitivity)? Also, I read about the 30 - 40 year lag, but also that ocean turnover takes 100s of years - and that these are not to be confused. But it is confusing. Why is the centennial turnover rate not a factor in ECS, and how does one make these distinctions when the physical processes of vertical mixing are so little understood? (At least, I have not found much in the literature or elsewhere that suggests we know more than a little about where and how vertical mixing takes place. I have enquired before, but no luck with recommendations so far)
  35. Review of Rough Winds: Extreme Weather and Climate Change by James Powell
    Okay, so in spite of my better judgement, I clicked a few of these - and there was good old Steve G, Prince of CherryPickerville. Including the infamous picture of USS Skate, supposedly at the 'ice-free' North Pole. That's the problem with a 'source' like C3: there is no vetting of the material cited, which leaves those gullible enough to take it on face value thinking, 'wow, that's a lot of information - must mean something.' We've had another player - friend PT - who operated the same way. It's also a Faux News tactic - 'people are saying that global warming is ... ', when the 'people' saying those things are the Faux News on-air talking heads. Repeat it often enough and it must be true, no? In addition, Norman: please note that many of these headlines are reports of disaster - bridge collapse, 400 dead, etc. You've specifically disputed the use of disaster counts as meaningful - yet here they are being used by you.
  36. Review of Rough Winds: Extreme Weather and Climate Change by James Powell
    [ response to deleted snipped ] The topic of this Thread is "Extreme weather and Climate Change". Finding a large sample of past extreme weather events that compare to those in James Powell's ebook should not be considered off-topic or extraneous. It is what the topic is about. The topic is Global Warming causing climate to shift in such a way that more extreme weather will be the result. If it can be clearly demonstrated that extreme weather events are not exceptional for these last few years (by showing large lists of past extreme weather events that are very similar to the ones brought up today), then that would seem a valid position to consider.
  37. Models are unreliable
    DB, I appreciate your response. In fact, I have already pointed out the fact that anomalies rather than absolute temperatures are used for the reasons stated by NOAA. My problem was that I was not sufficiently confident of my facts regarding the models to say for certain that the raw data output does not appear in the form of absolute temperature. It certainly wouldn't make sense for it to do so given that the global temperature datasets are presented as anomalies, but I wanted to check up first. Thanks, Paul
    Response:

    [DB] Apologies; I didn't mean to imply that you hadn't.  My intent was to provide you with a sourced, concise reference.  Sphaerica gives some good links to resources on models here.

  38. Ocean Heat Poised To Come Back And Haunt Us?
    Karamanski - without going into technical detail - think of how heat is lost by the human body when you sweat, the evaporation of moisture takes heat with it, cooling the skin. In much the same way, the same thing occurs over the surface of the Earth. Consider how much cooler local temperatures are in tropical forests (with lots of moisture) compared to dry regions of the world at similar latitudes. I'll track down some papers for you - if you're genuinely interested (I do remember a very recent one about forests and water recycling cooling the Earth surface). As for the PDO, AFAIK I don't think an actual mechanism has been discovered. So whether it can be responsible for anything is moot.
  39. Ocean Heat Poised To Come Back And Haunt Us?
    Karamanski, I assumed (anyone can correct me if I'm wrong) that it is a result of increased evapotranspiration/Latent heat. The added water on land gets less energy put into heat/temperature, because it goes instead into evaporating at least some of the additional water (which requires a substantial amount of energy -- 600 times more to evaporate water than to raise it 1˚C).
  40. Ocean Heat Poised To Come Back And Haunt Us?
    It doesn't make any sense how more rain over land would cool global surface temperatures during La Nina and how less rainfall over land would warm global surface temperatures during El Nino. I was also wondering what cycle governs when hiatus periods occur. Is it the Pacific Decadal Oscillation, or increased frequency of La Ninas?
  41. Review of Rough Winds: Extreme Weather and Climate Change by James Powell
    Daniel Bailey @214, I would hope that linking this sight does not undermine my credibility. Someone took the time (which would be a daunting task to compile) and gathered newpaper clippings of extreme weather events in the past. If one ignores the opinion of the author of the sight and concentrates only on the actual data (Newpaper clippings from around the world on extreme weather events) you get a historical perspective on severe weather events in number, intensity, and time frame. If you would insert Jeff Masters 2010-2011 weather compilation into this long list would it still stand out as something not seen since 1816? When looking at the whole globe, it would appear that somewhere they are experiencing extreme weather quite often. Look at some of the headlines in the long list of extreme event. Here is a sample: "1976: Worst Drought In England And Wales For 500 Years" "1951: Mississippi River Reaches Highest Level For 107 Years" "1951: 100 Degree Heatwave Lasts For 7 Weeks In Texas" "1952: Scientist Says Both Polar Ice Caps Melting At Alarming Rate" "1977: Worst Drought In California History - Year 2" "1977: Antarctica Iceberg Is 45 Miles Long & 25 Miles Wide"
  42. Models are unreliable
    With reference to my post above, I've now been given a link to the article it is apparently based on. It's from lucia at The Blackboard Has anyone come across this before?
  43. Ocean Heat Poised To Come Back And Haunt Us?
    Critical Mass - See Sutton & Roemmich (2011). Based on the observations, they indicate that most of the ocean warming is occurring below about 35°S. Not so co-incidentally the model used by Meehl (2011) indicates that is where most of the heat uptake to the deep oceans is occurring too, although I don't mention that in the post.
  44. Review of Rough Winds: Extreme Weather and Climate Change by James Powell
    213, Norman, Wow. That's just amazing. You (and your source) have proven that there have been extreme weather events prior to the advent of AGW, therefore AGW must not be affecting extreme weather events. Well done! Fantastic! Well, I'll certainly sleep easier tonight.
  45. Ocean Heat Poised To Come Back And Haunt Us?
    FundME - For the warm-coloured regions (in figure 4) - think of what happens when you pull the plug from the bathtub - you get this rotating mass of water as it disappears down the plughole. Those warm-coloured regions are gyres - rotating masses of water, and these are affected by wind speed. Increase wind speed and more heat is driven down into the deep. It's whole lot more complex than that of course, but that's the broad picture. Remember too, that the cool water brought to the surface during La Nina or La Nina-like periods, allows it to be warmed by the sun (that's how the ocean are warmed). So that surface layer, even though it is causing cooler global surface temperatures, is steadily gaining heat. These two processes are operating at the same time. Is that any clearer?
  46. Ocean Heat Poised To Come Back And Haunt Us?
    Joshag - Nice work there. I've not seen any observation-based studies which look at this issue, so I'll see if I can get a reply from some of the experts working on this. It does seem to support the decadal trends seen in the climate model though.
  47. Review of Rough Winds: Extreme Weather and Climate Change by James Powell
    Norman, why is it in your desire to prosecute your agenda (and it is patently obvious you have one) you first frequent the denialist and dissembling websites for ammunition rather than relying upon the science and the scientific method themselves? A hint: The words "Gore 'Lie-A-Thon' " on the top of your linked source should have been a tipoff of bias. And a very typical page at c3. Reliance upon this type of "source" undermines your credibility severely.
  48. Models are unreliable
    A blogger has just posted an objection to climate models that I haven't come across before. Hopefully someone here knows more about it than me. The claim is that: "By concentrating on anomalies they (scientists) hide the fact that the models get the absolute global temperatures wrong by as much as 2C." I was under the impression that temperature anomalies are used because they correlate well over large distances, whereas absolute temperature doesn't. This sounds like the type of argument that McKitrick and Essex might have used. Any ideas, anyone? Thanks, Paul
    Response:

    [DB] "By concentrating on anomalies they (scientists) hide the fact that the models get the absolute global temperatures wrong by as much as 2C."

    The key word in your quote is "hide".  Your blogger is operating under the premise that there is a conspiracy, therefore ____________ is true.  This is a blatant obfuscation, easily proven wrong.

    From the NOAA page:

    1. Why use temperature anomalies (departure from average) and not absolute temperature measurements?

      Absolute estimates of global average surface temperature are difficult to compile for several reasons. Some regions have few temperature measurement stations (e.g., the Sahara Desert) and interpolation must be made over large, data-sparse regions. In mountainous areas, most observations come from the inhabited valleys, so the effect of elevation on a region’s average temperature must be considered as well. For example, a summer month over an area may be cooler than average, both at a mountain top and in a nearby valley, but the absolute temperatures will be quite different at the two locations. The use of anomalies in this case will show that temperatures for both locations were below average.

      Using reference values computed on smaller [more local] scales over the same time period establishes a baseline from which anomalies are calculated. This effectively normalizes the data so they can be compared and combined to more accurately represent temperature patterns with respect to what is normal for different places within a region.

      For these reasons, large-area summaries incorporate anomalies, not the temperature itself. Anomalies more accurately describe climate variability over larger areas than absolute temperatures do, and they give a frame of reference that allows more meaningful comparisons between locations and more accurate calculations of temperature trends.

    NASA has a nice synopsis on models, here.

  49. Review of Rough Winds: Extreme Weather and Climate Change by James Powell
    michael sweet @212 It appears someone has already compiled a list of what I have been looking for. This person took extreme weather events from the 1950's, 60's and 70's and put them on a list. I will link you to this webpage and you can see what you make of it. List of some extreme weather events.
  50. Philippe Chantreau at 06:38 AM on 16 October 2011
    Continued Lower Atmosphere Warming
    Of course muon, that's the way it will inevitably be represented by some. There is nothing anyone can do about that. The attentive reader who wants to know will notice that Dr P in fact showed nothing. Sure he showed that there is no warming "trend" since 2002 but also readily acknowledged this was meaningless because no trend, or lack thereof, can be establish over that time period. Then when asked by why he would devote so much attention to a meaningless trend, he was rather evasive. I must say I found that whole exchange rather surprising considering Dr P's background. We had countless occurrences on this site of people arguing about meaningless short term "trends", I recall there were threads devoted to the explanations of why short term says really nothing. I do not remember any respectable scientist with a deep understanding of noisy time series making that same argument.

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