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Comments 120901 to 120950:

  1. CO2 lags temperature
    As to "committing embarrassing blunders", useful science requires predictive ability: What significant prediction of current or past climate science with CO2 as a forcing function have you not been embarrassed by? How far into the future was that prediction that came true? How long do we have to wait to know if your outstanding predictions are accurate? As far as science goes, you guys are still very much in your infancy at predicting global climate changes or even trends. What bets have you made on your predictions? What odds are you willing to give? There are so many basic unanswered questions about climate that get papered over by climate scientists... Why are the climate patterns of the last 500 Kyrs significantly different from the 1500 Kyrs prior to it? Climate tends to have cyclic patterns to it but also gets major non-cyclic perturbations to it. What will be the next perturbations that will impact climate trends? I mean besides the unpredicted changes in solar emissions of the last few years.
  2. Flowers blooming earlier now than any time in last 250 years
    Geo Guy #30 Parmesan 2003 is a very comprehensive study about biological responses to global warming, analysing phenomena in every continent, including migration patterns, blooming, species distribution, among others.
  3. Arctic Sea Ice (Part 1): Is the Arctic Sea Ice recovering? A reality check
    Peter, thank you for putting the Arctic ice information together so well with so many good references. I also added Polar Science Center to Bookmarks. Even before I saw this article and that graph though, it was apparent to me from the NSIDC site that Arctic ice volume has not recovered, so I have no idea why anyone says Arctic ice has recovered, and i do not consider attempts to explain that simple fact to people as 'backpedaling' in any way.
  4. Flowers blooming earlier now than any time in last 250 years
    Geo Guy, not to get into dueling cites but clearly the picture is not quite as muddy as first impressions from a single article may suggest. Here's the general state of things as they stood in 2008, from an article I selected in honor of Skeptical Science based as it is in Australia: Numerous (mostly Northern Hemisphere) studies have collated information on global changes in phenological events in response to recent climate change (Hughes 2000; Walther, Post et al. 2002; Hughes 2003; Parmesan and Yohe 2003; Root, Price et al. 2003; Chambers 2006; Parmesan 2007; Miller-Rushing and Primack 2008; Rosenzweig, Karoly et al. 2008). A recent study of 28 880 records of (mostly phenological) changes in biological systems throughout the world in the past 30 years has shown that 90% of the changes are consistent with changes in temperature (Rosenzweig, Karoly et al. 2008). Climate change due to greenhouse gas emissions over the past 50 years is more likely to have caused these changes rather than natural climatic variability (Rosenzweig, Karoly et al. 2008). Potential Biological Indicators of Climate Change: Evidence From Phenology Records of Plants Along the Victorian Coast
  5. Arctic Sea Ice (Part 1): Is the Arctic Sea Ice recovering? A reality check
    Peter @24, That graph says it all. Thanks unrecovered.
  6. Arctic Sea Ice (Part 1): Is the Arctic Sea Ice recovering? A reality check
    Humanity @20, "Alarmists made the most of the aberrant 2007 sea ice extent to push the worst case scenario's. Recovery from that aberration has left them back peddling." Yes, some people were perhaps overly concerned that the 2007 event was the beginning of the end, ands some rather silly dates were thrown around. But 20 years form now we may agree with them that 2007 was a paradigm shift, only time will tell. Regardless, the NSIDC et al. are not "back pedalling" as you are trying to suggest. Overall, the scientists have been level-headed on this. As noted by Dr. Hogarth above "an imminent dramatic change in this trend or “tipping point” is unlikely, at least in the Arctic (Notz 2009, Eisenmann and Wettlaufer 2009)," Some scientists (Dr. V. Pope I think) suggested that the demise of the Arctic ice sheet may occur in steps. Humanity, the old argument that "they (the alarmist) did it so the fact we did is OK" does not cut it. A agree with your observation that "Short termism on both sides of the argument are unhelpful." Humanity "I wouldn't dispute the downward trend for several decades or that the past two years can be considered a recovery." This statement is internally inconsistent, and is also inconsistent with the your statement that "short termism on both sides of the argument are unhelpful." The long-term trend is statistically significant, the short term trend is not, there is no way of getting away from that fact. Also, you do not quantify by what you mean by a "recovery" (recovery of what exactly, to what extent/volume, transient or long-term?). It seems that you are setting a very low bar for "recovery" and a very high bar for "downward trend". The animation from DMI that you show is, IMO, misleading. First, the data are for 80 N and we all know that the Arctic starts at 66.5 N, with most of the sea ice north of about 72 N. Second, the scale makes it really difficult to discern small changes. Third, your statement seems to assume that the ocean, air and ice north of 80 N are isolated from their surroundings, which is not true. Fourth, the satellite data showing changes in the melt season in my original post do not extend north of 82.5 N (?), but they do show an increase in the summer melt right up to the edge of the data void (i.e., north of 80 N). Fifth, the seasonal warming over the Arctic in the summer has been documented using ERA data by Graversen et al. (2008, Nature). See their Fig. 1. While most of the warming (between 1979-2001) north of 70 N was observed in the boreal winter and spring (surface trends >0.8 C per decade), surface warming was also observed in the summer (0.1 to 0.2 per decade; 0.4 C per decade near 70 N). And in the fall, the warming was >0.5 C per decade North of 70 N and >0.7 C per decade north of 80 N. Also see their Fig. 4 which shows thew warming trend between April and October north of 80 N to be at least 0.4 C per decade. By comparison, global temperatures are increasing at about 0.15-0.17 C per decade. In a response to Graversen et al. (2008), Grant et al. (2008) convincingly demonstrate using both sounding and ERA data that the near surface warming between April and October over the Arctic (incl. north of 80N) is significant (see their Fig. 1). They did find issues with the warming near 700 hPa found in the ER-40 analyses which did not seem to be supported by in-situ radiosonde data. That all said (phew), we have to keep in mind when looking at the ERA-40 data north of 82.5 N is that the data are no longer constrained by radiosonde observations, but rather sub-par satellite data (Thorne, 2008 Nature; critique of Graversen et al. 2008). The trends in surface data in ERA-40 north of 72 N do appear to be reliable and those data are showing a distinct warming trend between April and October (and also for the summer months) which is not easily teased out of the DMI animation. Interestingly, WUWT is fond of using that DMI graphic. I think that we all know why that is.
  7. Flowers blooming earlier now than any time in last 250 years
    The article only touches on the UK. A similar study done in Nova Scotia compared records from 1996 to 1998 and compared the results to those collected between 1892 and 1923 and concluded that the average spring climate in Atlantic Canada has remained cool since 1948, with a warming blip experienced in 1998. "Monitoring of Spring Flower Phenology in Nova Scotia: Comparison Over the Last Century, Litte et al; Northeastern Naturalist, Vol 8, No 4, Pgs 293-402” So here we have two studies with opposite conclusions, something that we always run into when we are trying to determine what is driving climate change. Now IF higher levels of atmospheric CO2 was the main driving force of climate change, and since the CO2 content quote is for the entire atmosphere, we should expect to observe similar data from two maritime environments such as the UK and Atlantic Canada, but we don't. To me that suggests there is more at play wrt climate change than simply higher levels of CO2.
    Response: The key is not to look at just one region (this post about UK trends is the first step to a broader post on global trends) but to see what's happening all over the world. Nevertheless, thanks for the link - what would've really made my day was if you'd added it to the list of Peer-review papers on advancing springs. I've gone and done that just now.
  8. Flowers blooming earlier now than any time in last 250 years
    "I wonder what effect an earlier spring will have on the most common food crops?" Most of the problems with the season shift is when you have loss of environmental syncronism. Something like the bees coming in April missing the flowers that bloomed in March. My amateur guess is that human-made crops won´t suffer much. On the contrary, I usually read something related to a longer growing season. The problem here will be more the temperature itself, and maybe some alterations due to more CO2.
  9. Flowers blooming earlier now than any time in last 250 years
    Zephiran #26 Thanks for pointing it out, but my comment was sarcastic. I think I´m not very good at that, since people don´t get it quite often... Of course, the emails don´t disprove anything. I keep reminding people that no scientific paper will appear showing the "hidden decline" - for the obvious reason that that temperature decline does no exist.
  10. Peter Hogarth at 02:32 AM on 14 April 2010
    Arctic Sea Ice (Part 1): Is the Arctic Sea Ice recovering? A reality check
    Unrecovered at 01:37 AM on 14 April, 2010 Many thanks, this is a great resource, well worth highlighting. Zhang et al, PIOMAS chart from Polar Science Center, Advanced Physics Lab, University of Washington.
  11. CO2 lags temperature
    Along the lines of getting caught up on what climate models actually do and how they work, Weart provides a nice, linear narrative covering the evolution of models. First some deep background: Simple Models of Climate Change
    Next, more recent developments leading more or less to the present: General Circulation Models of Climate
    Reading Tom's RC links as well as Weart's more pedagogical work will improve your ability to discuss this topic without committing embarrassing blunders. Elsewhere I've blithely mentioned spending "a few hours" reading Weart but in fact he's produced a synopsis of many decades and many careers of work just covering the effort and dedication devoted to models so in all honesty it does take a little determination to wade through the story. If you're interested in discussing climate models and climate change while staying within the boundaries of established history and uncontroversial facts Weart's narrative is well worth the time.
  12. Flowers blooming earlier now than any time in last 250 years
    With regard to trophic mismatch, the recent paper by Thackeray et al. (2010) "Trophic level asynchrony in rates of phenological change for marine, freshwater and terrestrial environments" to be published in Global Change Biology is worth a look.
  13. Flowers blooming earlier now than any time in last 250 years
    Alexandre, you should know by now that those e-mails don´t have any bearing on the scientifical debate. On topic. I wonder what effect an earlier spring will have on the most common food crops?
  14. Arctic Sea Ice (Part 1): Is the Arctic Sea Ice recovering? A reality check
    Up to date Ice Volume Anomaly Estimates can be found here: Ice Volume Anomaly
  15. CO2 lags temperature
    nhthinker, your description of climate models is incorrect, though your misconception is a common one. Climate models are not mere statistical models that are fitted to the observed data. Instead they are physical models that incorporate knowledge of fundamental processes. The predictions (and postdictions) emerge from that knowledge. You mentioned only two of the criteria for evaluating scientific theories--parsimony and predictiveness. You omitted several others, such as explanatory power and fruitfulness. As Einstein said (paraphrasing), make things as simple as possible, but not simpler. When we know about physical mechanims, a good theory must incorporate those mechanisms, no matter how complicated they are. For more information, see the RealClimate post FAQ on Climate Models, Part I and Part II. If you want to argue about that topic, those RealClimate posts would be appropriate places to do so, but unfortunately it looks like commenting is closed on those posts. I can't think of a Skeptical Science post that is appropriate for that topic, and off-topic comments often get deleted.
  16. Flowers blooming earlier now than any time in last 250 years
    Argus, 1) Do you contend, then, that the present warming is happening over the same sort of time-scale as it has done in the past, i.e. in a natural and slow fashion ? Do you believe that any past civilizations have collapsed due to climate change, i.e. that they weren't able to adapt in time ? 3) Also countered on this very site : CO2 effect is weak CO2 is not a pollutant CO2 effect is saturated 4) The link also says : "Because current climate change is so rapid, the way species typically adapt (eg - migration) is, in most cases, simply not be possible. Global change is simply too pervasive and occurring too rapidly." And : "The most well known study to date, by a team from the UK, estimated that 18 and 35% of plant and animal species will be committed to extinction by 2050 due to climate change." Still waiting for some examples of this 'catastrophe-anxiety'...
  17. CO2 lags temperature
    nhthinker, you wrote "Water vapor is a dramatically more important GHG than CO2." But water vapor is a feedback, not a forcing, as explained in this Skeptical Science argument: Water vapor is the most powerful greenhouse gas. If you want to discuss that topic further, that thread is the appropriate place.
  18. Flowers blooming earlier now than any time in last 250 years
    arrgghh... I meant Fox News, of course.
  19. Flowers blooming earlier now than any time in last 250 years
    It´s frustrating to see how flowers let themselves be influenced by media alarmism. Climategate has clearly proved that we´re not warming. Scientists hid the decline... Flowers should watch Fow news more often.
  20. Flowers blooming earlier now than any time in last 250 years
    By 'everything adapts' I did not mean that 'all the species that have ever lived are still among us'. I guess I meant that the 'global ecological system of all living beings' always adapts, as a whole.
    Of course. We even see that at the KT boundary. At the time, the dinosaurs might've argued that the fact that the biosphere would eventually adapt to post-catastrophe conditions was of little solace to them. The problem is the pace and magnitude of change, the impacts on today's ecosystems and human populations which are largely dependent on them. The fact that over millenia the boreal forests of canada and siberia might be replaced with ecosystems better adapted to a more temperate climate, and that over a very long period of time soils might be built up that some day, far in the future, might be able to support sustained wheat, corn and soy production, isn't going to provide tomorrow's farmers with much comfort.
  21. Flowers blooming earlier now than any time in last 250 years
    Robert Murphy (#14), By 'everything adapts' I did not mean that 'all the species that have ever lived are still among us'. I guess I meant that the 'global ecological system of all living beings' always adapts, as a whole. I also certainly agree that we should be ''making sure any changes that do happen are as gradual as possible''. It still is a natural thing that species come and go. They have done so long before humans started making fire and growing wheat, but as far as possible we should refrain from cutting down the rainforests, or eating all the dodo birds. Better stay out of the extinction business!
  22. Flowers blooming earlier now than any time in last 250 years
    HumanityRules, can you point to a single person that is now living because of smoking, alcohol, drug or gun restrictions/prohibition ? Meanwhile, why not have a read into how climate change is affecting British species : Lost life: England’s lost and threatened species Also, could you give a few names and referenced examples of any of those people ("who wish to influence policy") who are 'peddling the catastrophe' ?
  23. Flowers blooming earlier now than any time in last 250 years
    JMurphy (#14), My 'arguments' are partly 'countered', but that does not mean they are wrong. Your points: 1. Climate has changed before. Yes, and it is changing now. No need to worry now, unless you believe that the biosphere is in a state of unstable equilibrium, where any small change starts an avalanche of accelerating changes in all areas. Do you? 2. It's just a natural cycle. - I didn't say that! We are most likely affecting the present change in CO2, but it doesn't have to be bad. 3. CO2 has been higher in the past. - I didn't say anything about that either! CO2 is increasing now, and is higher than it has been for a long period before us, but it is still on a very low level - not even half of a tenth of a percent. Almost all living things need CO2 in the atmosphere. If there is more, more will also be used and absorbed. 4. Animals and plants can adapt... Yes they can and they do. I quote from your link: ''Global warming to date has certainly affected species’ geographical distributional ranges and the timing of breeding, migration, flowering, and so on.'' Even individual plants can adapt to milder or colder (or longer) winters. See epigenetics and paramutation! 5. It's a climate regime shift. - I never denied that the present global warming was caused by humans. I didn't even mention the topic. As for catastrophe-anxiety, it is evident all over the place on this site. It is not a 'strawman' argument.
  24. HumanityRules at 23:11 PM on 13 April 2010
    Flowers blooming earlier now than any time in last 250 years
    9.doug_bostrom Don't throw the brick. There's nothing witless in seeing a twelve day swing in spring onset in 150years as shown by this paper and suggesting that British wildlife is still doing its thing. It obviously is. Please point me to a single species in the UK that has gone extinct in the last 150 years as a result of this. 14.JMurphy The catastrophe isn't a straw man. That's what's being peddled with this subject and others. Maybe not by these authors or John but certainly by those who wish to influence policy.
  25. Robert Murphy at 22:33 PM on 13 April 2010
    Flowers blooming earlier now than any time in last 250 years
    Argus says (#13): "Yet the history of the earth shows repeatedly that changes happen all the time, for various reasons, and that everything else adapts to the changes." Actually, what Earth history shows is that only a tiny percentage of the species that have ever lived are still around; most by far could not adapt to the changing environment and went extinct. Everything most definitely does *not* adapt to the changes. We have a vested interest in making sure any changes that do happen are as gradual as possible.
  26. CO2 lags temperature
    Have you ever studied the concept of integration in calculus? CO2 as a forcing function is incongruent with the concept of sharp peaks at the beginning of interglacials. If you add a forcing function with a time delay to a base cyclic pattern or even a pulse function, it produces a curve that is completely different than what the last 500 Kyrs of data demonstrates. The current climate models are filled with fudge factors that are constantly being updated- And updated at a much faster rate than the planet position charts were prior to the invention of the mathematical model for gravity. I believe in Occam's razor- the complexity of today's climate models are very much analogous to the planet charts of the middle ages. Relatively simplified mathematical models of a reasonable number of variables should be all that is needed to explain the natural record without force fitting very odd shaped forcing functions. That is what hard science strives for. Water vapor is a dramatically more important GHG than CO2 is and it has only seriously been studied extremely recently- CO2 data has been around much longer. Much of what was thought as extensible to environments that have not been monitored will be proven wrong. "ScienceDaily (Apr. 29, 2008) — MIT Professor Dara Entekhabi will lead the science team designing a NASA satellite mission to make global soil moisture and freeze/thaw measurements, data essential to the accuracy of weather forecasts and predictions of global carbon cycle and climate. NASA announced recently that the Soil Moisture Active-Passive mission (SMAP) is scheduled to launch December 2012." Climate scientists are only now starting to get the tools that they need to make real progress. But in some ways, there is too much ego and passion involved in quarters on both sides of this debate. Point me toward a solution that passes the Occam's razor test. I do have an open mind. If you point me to a solution that seems overly complex to explain the data, then I expect it needs to provide accurate prediction to be a useful model. Very complex models that were intentionally force fit to previous data are not very compelling.
  27. Flowers blooming earlier now than any time in last 250 years
    Time to update the old saying; 'March showers bring April flowers'. Matches what has happened here in the northeast US the past few years perfectly.
  28. Arctic Sea Ice (Part 1): Is the Arctic Sea Ice recovering? A reality check
    Re: Hugh #19, actually 'sea ice extent' is NOT "critical" in determining the ice albedo effect. If you refer back to my previous post you will see that I mentioned the albedo effect and explained the difference between ice area (which directly impacts albedo) and ice extent (which can be up to 667% of the ice area). In short, the fact that 'sea ice extent' is a measure of OCEAN area with "at least 15% sea ice" means that a 100 square foot area of ocean completely covered by ice has exactly the same 'extent' as one with only 15 square feet of ice coverage... but the albedo impact is going to be hugely different. In response to the comment attached to my post #13... I wasn't saying that ice extent is in all ways meaningless. Rather that even a ten year trend of increasing sea ice extent would not mean that Arctic sea ice was recovering if the same ten year period showed arctic ice VOLUME decreasing. This is because ice extent is a proxy (with up to a 667% error rate) for ice area... which is in turn a proxy for ice volume (providing two of the three dimensions needed to calculate it). Likewise, since ice extent is heavily impacted by temperature, winds, and currents it could serve as a proxy for any of those. However, due to the huge error bands involved it is only useful for getting a general idea from very long term trends. Hopefully the just launched Cryosat-2 and NASA's forthcoming ice monitoring satellite will finally give us the ability to measure ice volume more precisely and consistently. Ice extent had been the only game in town, but using it for predictions has been a bit like guessing what a cloud will look like three days after you first spot it.
  29. CO2 lags temperature
    The emphasis of this article is that the half million year data showed carbon following temperature. You still seem to be not reading (or not grasping) the point. In the ice core record changes in CO2 may not be starting the warming/cooling swings, but changes in CO2 are most definitely amplifying the warming/cooling swings. In other words, adding CO2 to the Pleistocene atmosphere did produce more warming, and removing it from the atmosphere did produce more cooling. Now, can you explain some reason why CO2 would act as a greenhouse gas in the laboratory, and in numerical models, and in the ice core records, and in many other times during Earth's long history, and on Venus ... but would mysteriously stop being a greenhouse gas once Homo sapiens began constructing coal-fired power plants?
  30. Flowers blooming earlier now than any time in last 250 years
    You should add these to the list of positives to come from global warming: florists.
  31. Flowers blooming earlier now than any time in last 250 years
    Argus, your 'arguments' are countered on this very site (apart from the strawman about catastrophe-anxiety) : Climate's changed before It's just a natural cycle C02 has been higher in the past Animals and plants can adapt to global warming It's a climate regime shift
  32. Flowers blooming earlier now than any time in last 250 years
    -watchingthedeniers, doug_bostrom etc: Climatologists and their followers seem to be an extremely anxious species. They have absolutely no faith in the ability of the biosphere to adapt to changes. As soon as the temperature goes up or a glacier goes down by even the smallest amount, they seem to think a catastrophe is waiting around the corner. Yet the history of the earth shows repeatedly that changes happen all the time, for various reasons, and that everything else adapts to the changes. As for flowering and pollination, ever heard of epigenetics in plants and animals, for instance?
  33. Flowers blooming earlier now than any time in last 250 years
    Why the grouping in 25 year lots?
  34. Peter Hogarth at 18:23 PM on 13 April 2010
    Arctic Sea Ice (Part 1): Is the Arctic Sea Ice recovering? A reality check
    Wingding at 08:37 AM on 13 April, 2010 This is actually an interesting question. Though ice chart data from Russian waters does show some correlations (see Mahoney 2008), and it would be interesting to track where the sparse temperature data is from, we can agree (hopefully) that temperature is a major part of the story. The chart you have referred to is air temperature. As a fair proportion of the ice melt is basal melt caused by warmer waters we also have to factor this in, (as well as energy transport by currents and atmospheric variations). Unfortunately there is little Ocean temperature profile data from before the 1950s, but we do have a proxy, and that is Sea level rise. HumanityRules at 16:04 PM on 13 April, 2010 I think you missed the references to significant trends in lengthening melt season in the post? The somewhat misleading animation in your comment becomes a little clearer when plotted in full for the length of the record. I have plotted the NCEP data and the Danish Meteorological Institute data from 1958 (where the DMI series starts). I’ve added a simple trend line. I'll get a larger version available.
  35. Flowers blooming earlier now than any time in last 250 years
    #8 watchingthedeniers: There is a study of Australian butterflies reported on ScienceDaily. I don't know if it is published yet. http://www.sciencedaily.com/releases/2010/03/100318132510.htm
    Response: It looks like the paper (Kearney 2010) is being published this Saturday, March 17. Thanks for the link, I'm adding it to the evidence for global warming and list of peer-review papers.
  36. Flowers blooming earlier now than any time in last 250 years
    I am not aware of a single life form that doesnt depend on mobility for survival. Fish swim, birds fly, and even plants exhibit mobility by diffusing their seed and pollen in so many ways. This ability to move, migrate, etc., is proof that the environment has always been continually in flux. The ability for flowers to bloom earlier or later is a manifestation of this same reality.
  37. Flowers blooming earlier now than any time in last 250 years
    HumanityRules pardon me, it's late here, but using your conclusion about nature's resiliency I can apply the same logic to conclude that I can toss a brick through my living room window and simply call a glazier in the morning and have it fixed, no harm done. That observation begs the question: If I have the brick in my hand should I throw it, or set it aside? Put another way, am I a witless catastrophe, or a mindful human? Time for bed...
  38. HumanityRules at 16:04 PM on 13 April 2010
    Arctic Sea Ice (Part 1): Is the Arctic Sea Ice recovering? A reality check
    #18 wingding My guess is there isn't a great deal of confidence in the early part of the long term record extent shown here. As john might put it the meme of low ice in the 1930s and 1940s is pushed by skeptics. #17.Albatross You seem to have it the wrong way around. Alarmists made the most of the aberrant 2007 sea ice extent to push the worst case scenario's. Recovery from that aberration has left them back peddling. It's not unexpected that skeptics would make the most of that. You should be most critical of the extreme alarmists, they do more to undermine the science. Short termism on both sides of the argument are unhelpful. If this article is only about whether there is a recovery in arctic ice wouldn't it be simple enough to state one aberrant month (March 2010) is insignificant compared to several decades of loss. I wouldn't dispute the downward trend for several decades or that the past two years can be considered a recovery. My objection continues to be the assumption that this is down to temperature when other factors are obviously important, if not dominant. This article contains many sentances where the temperature/ice extent relationship is assumed. For much of the highest latitudes the melt season has remained unchanged for the past 6 decades. What is driving ice loss in this region?
  39. watchingthedeniers at 16:03 PM on 13 April 2010
    Flowers blooming earlier now than any time in last 250 years
    Have just read the paper: two things interest me. Firstly, this is a very robust piece of research, and again confirms the reality of AGW. Secondly, it provides a model for monitoring the impact of climate change ecological systems are global/regional and national levels. Is there anything in Australia and/or NZ that attempts to record data for a similar analysis(granted our historical records won't have the depth of the UK)? To me, that would be an additional line of evidence and an interesting compare and contrast.
  40. HumanityRules at 15:36 PM on 13 April 2010
    Flowers blooming earlier now than any time in last 250 years
    What is the significance in this case of the present 25 years being the earliest springs? Is there any significance to the mid 1800’s showing the latest springs in 250 years? The data shows that nature can cope with a great deal of variation without apparent catastrophes.
    Response: My next post somewhat addresses this - looks at how nature has coped with dramatic climate change in the past. This goes much further back than the last few centuries which have been fairly mild compared to some of the changes in the deep past. Should hopefully finish it tomorrow.
  41. CO2 lags temperature
    Ned, there is enough uncertainty on PETM to make me very hesitant to suggest the hypothesis as fact - but at least it is consistent. nhthinker - aerosols lead to cooling but only for brief periods of time because aerosols dont remain in the atmosphere. CO2 does. "The point of the new climate models is to show CO2 as a forcing function." Huh???? This would be news the modellers. CO2 IS a forcing. We can measure its forcing (3-4 W/m2) more or less directly even. See Evans 2006 The point of models is to see what happens with this forcing. Perhaps some careful reading of the science in its not us
  42. CO2 lags temperature
    Well, nhthinker, we're making history every day, so time will tell. Maybe it tells us already? How about looking at this from a slightly different perspective. What do you see happening now-- in the history of the past few years that is to say-- that controverts the underpinnings of our understanding of how C02 behaves as a component of our climate?
  43. CO2 lags temperature
    Ned, The emphasis of this article is that the half million year data showed carbon following temperature. The point of the new climate models is to show CO2 as a forcing function. Your reference to the preceding years 300 Kyrs data is only useful if it also shows a forcing function of CO2. I would be much more interested in analysis of periods of history that show substantial emissions of CO2- but I'm afraid that these CO2 emissions are also correlated with major emissions of soot and other particulates from volcanoes. My minimal understanding of these events is that they quickly lead to a deep cooling periods as opposed to long warming periods. I think climate scientists need to search out and highlight these historic events that are most like today rather than just saying today is different and is producing different results that can be predicted just based on computer models, laboratory experiments and short term regional analysis.
  44. Flowers blooming earlier now than any time in last 250 years
    1930 - 1978 seems to have rather late flowerings compared to 1900 - 1930 (as best as I can make out from eyeballing the graph (I find it hard to make out the start and finish of intervals on the x-axis) while 1753 - 1783 has very early flowerings despite its correspondence with the so-called 'Little Ice Age.' These figures seem counterintuitive when compared against what we know of climate in a time when reasonable instrumental records were available. I note too the extraordinarily high uncertainties in early data compared with the narrow uncertainties of the recent record, which makes me wonder about the validity of the splicing of the data.
  45. CO2 lags temperature
    because there is a lack of natural causes that can suddenly release CO2 as a forcing not a feedback In recent years, perhaps. But some mass-extinction events involved sudden increases in CO2 (PETM, various flood basalt episodes).
  46. CO2 lags temperature
    "If this article, instead of showing half a million years, actually pointed to data sets from history that shows a substantial burst of CO2 (with similar levels of dust that are being produced today) and show that there was clearly a jump in temperatures that could not be explained by solar variation then I would take notice." Tricky- because there is a lack of natural causes that can suddenly release CO2 as a forcing not a feedback. I'm sorry but to me this like refusing to acknowledge that we could send a rocket to mars because there wasnt a "natural" trip by an object from earth to mars. We can safely predict the course within known uncertainties however because we just use physics. So do climate models. What predictions from climate model do you think are poor? That they cant predict weather? They dont try to. To Ned's list, I would actually add the Hansen 1988 for actual forcings. Sure it has some issues but good effort for such a primitive model! (For more on this and current model/data comparisons see updates-to-model-data-comparisons Climate science has also predicted pretty accurately both the change in OLR from AGW gases and the increased LR energy received at surface from these gases.
  47. Flowers blooming earlier now than any time in last 250 years
    There is also the issue of senescence. Warmer temperatures have been shown to make crop plants reach "old age" before maximum biomass can be achieved-thus resulting in reduced biomass overall. So far from being beneficial, earlier flowering & warmer winter, spring & summer temperatures could actually result in very detrimental outcomes for our food supplies. Also, John, I'm interested in the part of the graph for c 1900-1930. Now I realise the flowering times for 1978-2008 is even lower than for the 1900-1930 period, but did the author offer an explanation of why it was so low compared to the rest of the pre-1978 period? I'm guessing it had to do with the warming we got in the first part of the 20th century, but would just like that confirmed. Thanks :).
  48. watchingthedeniers at 12:35 PM on 13 April 2010
    Flowers blooming earlier now than any time in last 250 years
    Great article, and yet another example of a prediction made by climate science. So, how do the deniers try and spin this? Check you WUWT? http://wattsupwiththat.com/2010/04/06/global-warming-and-%e2%80%9cthe-early-spring%e2%80%9d-part-ii/ Apparently we don't need to worry, the paper's results are just a "myth". When it contradicts your world view, well deny.
    Response: Thanks for the WUWT link. I'd completely forgot that there is actually a skeptic argument denying that springs are advancing. I was only highlighting this study as I'd just added it to the evidence for global warming. But as there are some who don't even think springs are advancing, I've added a 106th skeptic rebuttal "Springs aren't advancing". For now, it just includes this UK study but will expand it to cover the rest of the globe shortly.

    Also, I set aside some time each day to add peer-reviewed papers to the links directory. I've just added Amano 2010 to the list of peer-reviewed papers on advancing springs. Anyone else who knows of other papers on this topic, please feel free to submit them to the directory.
  49. Flowers blooming earlier now than any time in last 250 years
    Robrtl, you'd certainly think so until you discover that complications arise, such as a food supply becoming available and then ending prior to the requirement of organisms depending on that food supply. Did you read John's article? ...a change in timing of plant flowering can disrupt the creatures that pollinate them. Similarly, changes in timing of plant or insect behaviour can affect the birds that use them as food supplies. Google on the topic and you'll see the complications emerge more fully.
  50. Rob Honeycutt at 12:24 PM on 13 April 2010
    Flowers blooming earlier now than any time in last 250 years
    @robertl... As my mother always said, "Be careful what you wish for."

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