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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

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Comments 67901 to 67950:

  1. Roy Spencer on Climate Sensitivity - Again
    Tom @51, Many thanks. This exercise reflects very poorly on Spencer and Christy.
  2. Updating the Climate Big Picture
    mace, we do already have the warming expected from the lower end of the range of climate sensitivities. Your link indicates that the surface temperature anomaly in the 1880s was -0.25 - -0.3 oC when [CO2] was ~293 ppm. The anomaly in your record is now 0.55 oC. So the warming is 0.8 - 0.85 oC over that period from your data. A 2 oC climate sensitivity should give an equilibrium warming of ~0.85 oC on raising [CO2] from 293 ppm then to 394 ppm now. So we've had pretty much all the warming already that is expected from the lower end climate sensitivity of 2 oC. Since the bulk of that warming has come from hugely enhanced increase in rate of [CO2] since the 1970's (i.e. relatively recently) we've got quite a bit of warming still to come as the Earth surface tends towards equilbration with the enhanced forcing. And that amount of warming has accrued despite the rather significant cooling contribution from greatly enhanced release of manmade atmospheric aerosols. Since the evidence indicates that natural warming contributions over this period (largely solar) have been small, this rather large temperature rise is in itself indicative that climate sensitivity is more likely nearer the middle of the range (i.e. near 3oC for a forcing equivalent to 2 x [CO2]) than the lower end. (one should also factor in the contribution to warming from other greenhouse gaes including methane, nitrous oxide, tropospheric ozone and CFC's....)
  3. Roy Spencer on Climate Sensitivity - Again
    CBDunkerson @44, You noted about Eric's comments here that, "you seem very concerned that the Washington Post article and/or graph could be misinterpreted to mean something other than intended but still true... but not particularly put out that what Spencer and Christy are saying is blatantly false." That is the exact same impression that I have. We can debate the semantics of how the graph might have been better, but the message of that graphic is very (inconveniently) clear-- the UHI data were biased on the low side, and when Spencer and Christy eventually did start implementing the corrections, some from the RSS team, some of their own, in the majority of cases the corrections increased the temperature estimates. There are a number of problems here: 1) Spencer and Christy, to this day, remain way too confident in the veracity of their product and repeatedly overstate the robustness and accuracy of the satellite inferred temperatures, while greatly exaggerating uncertainties in the surface temperature record. 2) When told back in 1997 by Hurrell and Trenberth that their product likely had a significant cool bias, they dismissed it and made excuses (more on that later). Yet to this day they claim that they are interested in producing a robust product. 3) They are using their data to play politics and mislead politicians, the public and policy makers. 4) Even now Spencer and Christy are bending over backwards and cherry picking to lower the warming trend in their own data. For example, Christy cherry-picking 1998 is beyond belief. That issues has been dealt with so many times I have lost count (most recently here), but that does not stop Spencer and Christy peddling his nonsense in late 2011. 5) Spencer and Christy still have not released their code used to calculate the temperatures from the satellite data. That did not stop Christy from testifying before congress that their code was freely available. There are probably more disturbing issues with this saga, so feel free to add them. I'm writing something up on how badly Spencer and Christy have behaved on this file and will post it soon. I'm amazed that Spencer and Christy have not been investigated by UAH for scientific misconduct. Their repeated misrepresentations, cherry-picking, distortions, exaggerations, and their politicization of science are reprehensible and the very antithesis of good science. Unbelievably, Spencer has the gaul to accuse other scientists studying attribution of "pseudo-scientific fraud".
  4. Roy Spencer on Climate Sensitivity - Again
    Dana @54, Christy, Spencer and Braswell, 2000 attribute the discovery of the orbital decay adjustment they make to Wentz and Schabel (Wentz, F. J., and M. Schabel, 1998: Effects of satellite orbital decay on MSU lower tropospheric temperature trends. Nature, 394, 361–364.) The diurnal correction in 2005 is attributed to Carl Mears and Frank Wentz of RSS in Christy's readme file. Sorry, 3:22 am here so this is definitely my last post of the night.
  5. Roy Spencer on Climate Sensitivity - Again
    Tom, thanks for the analysis. Didn't UAH come up with the +0.1°C/decade orbital decay correction though? I thought I remembered Spencer taking credit for that, or maybe it was the diurnal drift (I know RSS identified at least one of those two).
  6. The Media & Global Climate Science Communication
    First, I just want to thank you for all the work you do to keep this website going. It is a terrific resource. That said, take no offense at my questions below. I am easily confused by lack of definition, and am frustrated, but not with you, with my confusion. Please note the first post question for this column (not from me), in these comments. I hope you will respond to that poster's question. It would be very helpful for me, if you could actually define "negative" and "positive" for these charts. Does negative mean the article or headline says there isn't GCC, or that there might be, but humans are not to blame/can't fix it/it is "normal" cycles, or they were against policy changes or money budgetted toward the problem? And must "positive" articles/headlines be 100% in agreement with science and policy? Where do articles with mixed results land? I would very much love to share these charts, but first, I need to know something of the parameters that put an article or headline into one category or the other. Again, thank you, thank you, for your website. Best, Shoe
  7. Roy Spencer on Climate Sensitivity - Again
    CBDunkerson @52, I suspect that you are mostly right, but I cannot know that without somebody sufficiently expert getting their code and going through it with a fine tooth comb. However, I am sure the adjustments are legitimate. The problem is that the method of correcting a known warming influence (ie of making a cooling adjustment) is not always implicit in the data. Different teams might use different methods without it being possible to demonstrate which method is better from the satellite data alone. So while the reasons for the adjustments are probably legitimate, the method of adjustment may well have seen a consistent bias towards methods that show lower trends.
  8. Updating the Climate Big Picture
    An excellent article that sums up the main points of the science. As the article says we need to concentrate on determining the feedback mechanisms so that we can provide a better understanding to the general public of what the future temperature increase will be. We know that a doubling of CO2 from 280ppm to 560ppm should produce a temperature increase of 2-4.5C. However, it's also clear that we don't currently have the 0.78C anomaly that the lower end of this range would predict for the 39% increase from 280ppm to 390ppm. The expected 5 year mean anomaly for 2011 is about 0.55 based on the annual figures and projected monthly figures from GISS http://data.giss.nasa.gov/gistemp/_graphs3/Fig.A2.txt I feel we need a more convincing strategy than to label our opponents as skeptics or denialists who don't understand the science. We should concentrate on the science rather than getting in to arguments which could be construed as overly defensive.
  9. Roy Spencer on Climate Sensitivity - Again
    DB wrote: "I demur. Stating something that is "Completely false" is misleading." Well, fine... if you're going to get all 'technical' about it. :] Thanks for the detailed analysis Tom. On your point about the existence of 'cooling' adjustments... I think it is still valid to say that errors in Spencer & Christy's work have consistently been biased towards cooling. Indeed, some of their cooling adjustments are likely examples of this problem, and even if there are correct cooling adjustments they are clearly very minor compared to the cooling errors.
  10. Roy Spencer on Climate Sensitivity - Again
    Update to my 39 and 40: Going exhaustively through the readme file for the UAH TLT dataset, I found listed the following significant adjustments: Version D: 4 Feb 2000 +0.013 C/ Decade 6 Oct 2000 +0.002 C/Decade 2 Nov 2001 +0.002 C/Decade 8 Apr 2002 +0.012 C/decade Version 5.0: 7 Mar 2003 +0.02 C/decade 5 Feb 2004 +0.002 C/decade 20 Aug 2004 +0.02 C/decade 7 Aug 2005 +0.035 C/decade 5 Dec 2006 +0.01 C/decade Together with prior adjustments, these amount to a cumulative adjustment of 0.146 C/decade. However, I note that the switch between version D and version 5 is quoted as generating an adjustment of +0.008 C/decade in the table above, and in the peer reviewed literature whereas it shows a cumulative adjustment of +0.029 C/decade in the readme file. Any such discrepancy must be resolved in favour of the peer reviewed literature, and therefore I propose to treat the readme file adjustments as ad hoc, and likely to be superceded without notice. Therefore I will ignore them. That being the case, the cumulative adjustments to the UAH TLT record add a trend of 0.069 degrees C per decade to that which would be shown by the original method. That represents 49.3% of the current 0.14 C/decade trend. To place that into context I calculated how much the 97/98 El Nino added to the trend by the simple expedient of calculating the base trend, and then recalculating the trend with all values during the El Nino period adjusted to parity with those of the immediately adjacent months (0.02 C). The adjusted trend was 0.008 C/decade less than the true data, showing that the 97/98 El Nino added 0.008 C/decade to the overall trend. That represents just 5.7% of the total trend, and just 11.6% of the effect on the trend of the various adjustments. Returning to Christy, we recall that he said:
    "The major result of this diagram is simply how the trend of the data, which started in 1979, changed as time progressed (with minor satellite adjustments included.) The largest effect one sees here is due to the spike in warming from the super El Nino of 1998 that tilted the trend to be much more positive after that date."
    Describing adjustments that account for nearly 50% of the entire trend as "minor satellite adjustments" is misleading at the minimum. This is especially so as the single largest contribution to the trend (comparing adjustments and individual years) was the 0.035 adjustment found by Mears and Wentz, which represents 25% of the final trend. The largest single change in trend from year to year is the change of 0.1 C/decade between 1998 and 2000 (publication dates). In that change, the components where: Orbital Decay Adjustment +0.1 C/decade Hot Target Adjustment -0.07 C/decade 97/98 El Nino +0.07 C/decade It is true that the El Nino represents 70% of the net change in trend. However it is also true that the Orbital Decay Adjustment amounts to 100% of the net change in the trend. Picking the El Nino as being the most important part of that change is dubious at best. Saying that the largest effect is the spike due to the El Nino without mentioning that 30% of that spike in trends was due to the net adjustment is also misleading (at best). Finally, it is sometimes incorrectly stated by "warmists" that Spencer and Christy never find adjustments themselves, or that all the adjustments have been in one direction. In the chart @39, the two adjustments in red where found by other teams, whereas all other adjustments where found by Spencer and Christy. Further, there are clearly both positive and negative adjustments. Therefore both of these "warmist" beliefs are myths and should not be repeated. However, it is possible to note that the cumulative adjustments found by Spencer and Christy sum to a -0.066 trend. In contrast, those found by other teams sum to +1.35 C/decade. Interestingly, that means that left to their own devices, Spencer and Christy would still be reporting a trend of 0.05 C/decade. Given that their product has been an outlier sitting well below other temperature products from the beginning, the trend of their adjustments (excluding those found by other teams) is troubling to say the least. This is not a record you can look at and say with confidence that the scientists involved have not let biases guide their work. Characteristically, Spencer hints that they have another negative adjustment in the pipeline already.
  11. Roy Spencer on Climate Sensitivity - Again
    Tom @40 - I'd be interested in seeing a more accurate record. It would be useful for the response post.
  12. Foster and Rahmstorf Measure the Global Warming Signal
    Re: skept.fr @ 57, and others Aerosol Optical Depth is usually measured using sun photometers, which have a series of narrow-band filters (a few nm wide) to take direct sun measurements at selected wavelengths. Yes, such methods are biased towards clear skies. The largest network with international coverage is NASA's AERONET. Look there for data, methods, etc. Another international network is the Global Atmosphere Watch PFR network, run out of Switzerland. There's is probably the best instrument, but there are far fewer of them that in AERONET. Measurements can also be made using "Rotating Shadow Band" instruments (also filtered), such as those by the USDA UVB Monitoring Network.
  13. Ocean Acidification Is Fatal To Fish
    The results of the cod project that Arkadiusz refers to can be found here: http://www.codyssey.co.uk/ I think it should be pointed out that the research wasn't designed to investigate whether overall increases in temperature would be acceptable (eg increases across the board). In fact the site gives the impression that cod rested in the warmer temperatures, eg didn't feed.
  14. Foster and Rahmstorf Measure the Global Warming Signal
    mace#69: "if the oceans are getting warmer than why is the La Nina in 2010/11 cooler than that in 2000?" Let's not turn this into an el Nino/la Nina-centric discussion; there are several existing threads for that. The point here - really the core of Foster and Rahmstorf - is that these short term oscillations are noise written on the underlying signal. The amplitude of these oscillations is still large enough to make it look like 'it's cooling' when in fact that is just noise. FR removes the noise; without taking that step, we will still see occasional years that look cooler than they 'should' be. In fact, that's one way to show they have done an excellent job of separating the trend from the noise. But you seem to be confusing 'index' with 'cooler'. Look here for a description of how MEI is calculated.
  15. Foster and Rahmstorf Measure the Global Warming Signal
    So, what I'm essentially saying is that given that the La Nina in 2010/11 had a greater cooling effect than that in 2000, yet 2011's global mean temperature is higher, then this means that another forcing agent must be responsible for raising the temperature and most likely that's manmade pollution. However, given that the oceans are getting warmer due to global warming, you would expect the La Nina in 2010/11 to have a reduced cooling effect as well, so 2011 should be warmer than what it is. Do you see my point? Our sea level predictions are dependent on the oceans getting warmer as well as the ice melting, but if the oceans are getting warmer than why is the La Nina in 2010/11 cooler than that in 2000?
  16. Foster and Rahmstorf Measure the Global Warming Signal
    @Tom Curtis. Sorry, you misunderstood what I was asking. If you take a look at the Multivariate ENSO Index (MEI) figures in the chart in the article, the La Nina from autumn-2010 to summer-2011 had a cooling effect that was more pronounced than the one in 2000. I agree that 2010 as a whole had the highest global mean temperature and 2011 will be the hightest global mean temperature of a year where part of it had a La Nina.
  17. Arkadiusz Semczyszak at 01:26 AM on 23 December 2011
    Ocean Acidification Is Fatal To Fish
    The results of both the cited works are very precise and should be simply to accept. The facts are not discussed, but ... ... but in no case, however, they authorize author's post above - R.P. - the title of post: “Ocean Acidification Is Fatal To Fish“ I propose this presentation . And are there any conclusions, eg: “How can acidification affect fish/fisheries? • Through growth – Ecological effects • Change in food quality, quantity, timing • Reduced growth may affect the fertility • Reduced growth may reduce survival – Direct physiological effects? • Through mortality • Physiological effects? How can acidification affect fisheries? • Through recruitment – Early life stages of fish (eggs, larvae) are likely to be vulnerable to change in pH – Changes in the plankton community may reduce survival in the early life stages due to: • Food quality • Food quantity • Timing – match/mismatch • Predation We are now facing a future with lower pH and higher CO2 that in combination with a rising temperature most likely will be unfavourable - at least for some species in some ecosystems.” ... but even these conclusions are there too, and such general - very important - the main comments: „Acidification – Effects on fish stocks and fisheries: • Nature and degree of effects are largely unknown • Both direct and indirect effects are anticipated • Effects likely to be highly diverse, depending on, i.a., ecosystem, fish species, state of exploitation • Effects may be confounded by effects of climate change and overfishing” To this I add Hoffmann & Sgrò (2011): “Evolutionary adaptation can be rapid and potentially help species counter stressful conditions or realize ecological opportunities arising from climate change.” Staying near the Baltic coast I very much like cod fishing - with the cutter. About the Baltic cod is here. Cod has 9 subspecies. Cod is the "old" species of fish - has a great adaptive capacity. According to some evolutionists - gene mutations provide adaptation - almost immediately - to the very rapid climate change, there is always a population of significant size This rapid change in the environment gives them mutations - "asleep" mutations accumulated in the population - “the chances”. It was found that species such as plants that bloom in the wild in only one color genes are virtually all colors. This is called "black & white cow effect" - which never occurred in nature. Moreover, it is worth noting that the maps - the location of many economically important species of marine organisms in this presentation (for example, slide 9 - No 13 Atlantic Cod) - waters are often the lowest pH . Perhaps it is coincidence - areas of low pH is usually also fertile areas for reasons other than pH: estuaries, shallow shelf, upwelling zones, etc. . However, it is known that eg the availability of many microelements (eg iron, manganese) strongly increases at a pH below 7.5. Lowering the pH can - in many areas of large surface - to increase NPP. Powerful ocean areas (up to 75% of the area) with a higher pH are “biological deserts” (as compared to those with a lower pH). In addition, remember that laboratory testing are not always confirmed by experiments in the environment. This was the case with cod and temperature. “ScienceDaily (Apr. 29, 2006) — Scientists at CEFAS (UK) have found that the migration pattern of wild cod is much less restricted by environmental temperature than laboratory studies suggest.” “... scientists following movements of wild cod equipped with electronic tags that record depth and temperature have found that whilst some fish prefer deeper cooler waters, others tagged at the same time prefer to swim in shallower habitats in the Southern North Sea where summer temperatures are consistently above 17ºC. [in the experiments it was: 11-15 ºC]”
    Moderator Response: Please try be brief and on topic. Your theories of everything are, shall we say, difficult to follow.[Doug]
  18. Foster and Rahmstorf Measure the Global Warming Signal
    mace @66, who says La Nina's are not becoming less pronounced? The graph below shows the various La Nina years in blue. If you look closely you will see a pattern. They are getting warmer. Indeed, the last two La Nina's have been warmer than every recorded El Nino year prior to 1998. If that is not becoming less pronounced, I don't know what is. What has not happened, is that La Nina's have not become less pronounced relative to years within the same decade. But there is no reason why they should. Just as La Nina's are getting hotter for La Nina's, normal years are getting hotter for normal years, and El Nino's are getting hotter for El Nino's. So the short term contrast between El Nino's and La Nina's remains the same, and is expected to. Meanwhile, in the long term La Nina's are hotter than the El Nino's my father used to enjoy (and that I enjoyed as a child).
  19. Climate's changed before
    mace @303, humans emerged in the Pleistocene as hunter gatherers in small groups of from 50 to 200 individuals. There is nothing in the consequences currently predicted from global warming that would make the life of small groups of hunter gatherers particularly difficult. In contrast, humans did not invent agriculture, cities, or civilization until the Holocene. There is a reason for that based in climate. During the Pleistocene climate was very variable over short time spans, with variations in temperature of up to half a degree C occurring in the space of a few hundred years, a condition likely to be inimical to agriculture. And certainly there is much in the potential consequences that will make agriculture much more difficult. So the question for your denier friend is, does he want all 7 billion of us to go back to being hunter gatherers? And how many of us does he think would survive if we did? Because todate, only Holocene conditions have proved capable of supporting agriculture, and we are rapidly leaving those conditions.
  20. Ocean Acidification Is Fatal To Fish
    The cause of this slow growth, deformation and decline in survival rates in the experiments is not known, but given that inland silverside can grow and thrive in more acidified freshwater, this suggests something other than pH. Baumann (2011) suggest this may be related to high CO2 levels, or even the carbonate chemistry of the water.
    I'm not sure that I'd completely dismiss pH itself as a contributor to altered growth and/or development in all marine fish. It has been known for many decades that the eggs/zygotes/larvae of many freshwater fish are exquisitely sensitive to hydronium ion concentration. Ask any serious breeder of some of the finnicky South American characins for a start - although the phenomenon is recognised in many taxa. Ironically, in fresh water it is often acid-loving species that are sensitive to changes in pH. Certainly carbonates and other salt species are enormously conspicuous components of the saltwater chemical milieu, and quite possibly dominate most piscine physiological responses to varying concentrations of dissolved ions, but hydronium itself is physiologically important. Changing its concentration in an environment that it extremely consistent by ecophysiological standards is quite possibly going to affect sensitive growth stages of at least some marine fish species, either by itself or in concert with coincident chemical changes arising from increase in ocean carbonic acid concentration. Whatever the mechanism, it should come as no surprise to most fish physiologists that pH will tend to target the early life-stages of fish. I've been speaking of such vulnerability for years, and I suspect that in a few more decades, should carbon emission control remain as limp as it has been to date, there will be a recognised crash in recruitment to quite a few important (and many not-so-important) marine fish stocks, arising directly from physiologial mal-adaptation to altered hydronium ion concentration.
  21. Ocean Acidification Is Fatal To Fish
    I see your point DB. Sorry, I just want to arm myself as much as possible to combat some denialist rubbish coming my way at the moment. Please don't put me in the same bucket as those nutcases.
    Response:

    [DB] "Please don't put me in the same bucket as those nutcases."

    I do not.  However, repeating a meme gives it undeserved life.  Perhaps a slight rephrasing of your statements would be more effective:

    "One thing that I've heard repeated in some circles is that the temperature and CO2 spikes that occurred during the Pleistocene period were greater than what is happening today.  Can someone help me understand why this statement isn't true or relevant to today?"

  22. Climate's changed before
    Hi all, I've been directed to this great post by DB. Unfortunately, it doesn't quite counteract the argument that has been presented to me by a denialist. In the Pleistocene period, human beings first emerged http://en.wikipedia.org/wiki/Pleistocene yet the climate history is telling us that there were some severe spikes and troughs during that period. http://en.wikipedia.org/wiki/Paleoclimatology Is the current increase in global warming greater than those experienced during Pleistocene periods? Can you provide me with a peer-reviewed paper that would help me to combat this denialist rubbish.
  23. Roy Spencer on Climate Sensitivity - Again
    I demur. Stating something that is "Completely false" is misleading.
  24. Foster and Rahmstorf Measure the Global Warming Signal
    @DB. The peer-reviewed paper in the article is saying that if you remove the effects of solar irradiance, aerosols and ENSO, then the warming trend continues. The article says "Foster and Rahmstorf find that ENSO has the largest impact on short-term temperature variations", as indeed is shown in their graphs. The graph is showing a cooling effect caused by La Ninas in 2008 and 2010, which accounts for what skeptic-deniers perceive to be the flattening in the warming trend. La Ninas are caused by upwelling of cold water, so my question is that given that the oceans are absorbing a lot of heat, why aren't the La Ninas getting less pronounced?
    Response:

    [DB] "why aren't the La Ninas getting less pronounced?"

    Who said the La Ninas would get less pronounced? The La Ninas themselves are warming up.  The most recent La Nina was the warmest on record, warmer indeed than many El Ninos.  What you are missing is the incomplete temperature monitoring of the ocean deeps.  Thus, what may seem like a "cooling effect" in the surface temperature record (which statistically is still warming during the La Nina) misses the injection of heat into the deep. Essentially, ENSO causes a redistribution of heat (thus the use of the word "variations"), but overall does not warm nor cool the Earth.

    In the face of said posited "cooling", ask yourself how it is then that the most recent decade is the warmest in the surface temperature record?

  25. Roy Spencer on Climate Sensitivity - Again
    Eric wrote: "That is not particularly clear but not misleading." Misleading, no. Completely false, yes. The El Nino was NOT the largest effect. See Tom's analysis above and his subsequent note about additional adjustments which weren't included in the chart.
  26. Roy Spencer on Climate Sensitivity - Again
    Just looked at Christy, Spencer & Braswell 2000 which acknowledges that they were not the first to find the errors. They also point out that their trend estimate of 0.06 was plus or minus 0.06 and that error range does not include the shortness of the time series nor future unknown errors. At the very least the graphic in post 27 and the Washington Post should have shown those error bars.
  27. Roy Spencer on Climate Sensitivity - Again
    CBDunkerson, 61% is not minor, and the Washington Post caption is misleading. As far as S&C, their blogging style is poor point scoring and Spencer in particular is always changing the topic. Their heading for the graph is "The major result of this diagram is simply how the trend of the data, which started in 1979, changed as time progressed (with minor satellite adjustments included.) The largest effect one sees here is due to the spike in warming from the super El Nino of 1998 that tilted the trend to be much more positive after that date." That is not particularly clear but not misleading.
  28. Roy Spencer on Climate Sensitivity - Again
    For those readers who are not familiar with Spencer and Christy it should be pointed out that Spencer and Christy did not find the errors in their temperature measurements. The errors were pointed out by other scientists and only then did Spencer and Christy correct their mistakes. Usually scientists find their own errors. Since there were so many errors to be corrected, and S&C consistently errored in the negative direction one wonders why they are usually low in their measurements.
  29. Roy Spencer on Climate Sensitivity - Again
    To put it another way, you seem very concerned that the Washington Post article and/or graph could be misinterpreted to mean something other than intended but still true... but not particularly put out that what Spencer and Christy are saying is blatantly false.
  30. Ocean Acidification Is Fatal To Fish
    Thanks, it would be useful, if the chart located here http://en.wikipedia.org/wiki/Paleoclimatology showed how today compares with the rest of known history. skeptic-deniers can point to the spikes that occurred during the pleistocene period as being greater than what happened today, for example, a period during which humans emerged as a species http://en.wikipedia.org/wiki/Pleistocene
    Response:

    [DB] "skeptic-deniers can point to the spikes that occurred during the pleistocene period as being greater than what happened today"

    You mean as you are doing now?  Your concerns are better addressed in the Climate's changed before thread.  And you are incorrect for multiple reasons.  Please read the referenced thread and place any remaining concerns there.

  31. Roy Spencer on Climate Sensitivity - Again
    Eric, it is entirely accurate to call the chart a list of corrections because the papers cited were corrections. Yes, the warming trend would also change over time, but as has been demonstrated above, that is a relatively minor contributor... Christy's claim to the contrary is; A: Demonstrably false based on the numbers. B: Directly contradictory to the original claims in their press release that their results were biased high (Ha!) due to anomalously cool years in the early part of the record and thus showed that the warming trend was declining over time. I suppose a chart could have been constructed to calculate the trend only over the period covered by Spencer & Christy's original report (i.e. up to 1995) based on each stage of the corrections, but obviously that would have required access to all the past values rather than just citing the trends that Spencer & Christy themselves reported at various points. It would also then be 16 years out of date. A 'perfect' comparison would require using the base satellite data and their different methodologies / calculations (which I don't believe they release) from each stage of revision to compute a trend up to present. If anything, given that they had several issues which introduced progressively larger cooling biases over time, that would likely show a much larger divergence. Finally, in your most recent post you ask how people would interpret "corrections"... but I don't see why. Either of the possible interpretations you cite would be entirely accurate.
  32. Foster and Rahmstorf Measure the Global Warming Signal
    Looking at the info, it seems that it's mainly the ENSO that's had an effect over since 1998 to make it appear that global warming has ended, which is what the skeptic-deniers always claim. I guess a logical question is, as global warming is causing the ocean to warm up, why is the cooling effect of the La Nina still so pronounced?
    Response:

    [DB] "it seems that it's mainly the ENSO that's had an effect over since 1998 to make it appear that global warming has ended, which is what the skeptic-deniers always claim"

    You mean the denialist meme you are repeating? 

    "why is the cooling effect of the La Nina still so pronounced"

    What cooling effect?  Please read the OP again.  You must've missed this bit:

    All five data sets show statistically significant warming even for the time span from 2000 to the present

  33. Ocean Acidification Is Fatal To Fish
    mace @23, what the article tells us is that high CO2 levels are in and of themselves something fish need to adapt to. It has previously been known that many fish species are threatened by the probably loss of coral reefs, and of many species of planckton which will be adversely effected by high CO2 levels. That lead to risks to fish populations due to starvation (among other causes). But we now know fish themselves face direct adversity from rising CO2 levels.
  34. Ocean Acidification Is Fatal To Fish
    What we need to be doing is to improve our models so that the skeptic-deniers don't have any ammunition. The previous article which shows that removing the effects of solar irradiance, aerosols and ENSO keeps us on track for a constantly warming planet is, in my opinion, the way forward.
    Response:

    [DB] "What we need to be doing is to improve our models"

    Please take your concerns to the Models are unreliable thread.

  35. Ocean Acidification Is Fatal To Fish
    mace @19 &20, as already indicated by John Bruno, what is different is that modern fish have adapted to pre-industrial conditions of low CO2 concentration. What he has not given you is the appropriate perspective on time. To gain that, consider the problem of lactose intolerance in humans. The important thing here is that cows milk, which is rich in lactose, is a readily available food source rich in nutrition and very commonly used in Europe. Being unable to use milk or milk products represents a major problem, and in pre-industrial times a significant impediment to survival. Cattle where first domesticated some 9 thousand years ago. The original Indo-European language (the language of the ancestors of nearly all Europeans) included a word for cattle. So Europeans have been relying on cattle, and cattle products, especially milk for around 4 thousand years at least. Yet there are still Europeans who are lactose intolerant. Four thousand years is insufficient time to fully evolve lactose tolerance in the the European population. Fish will not have 4 thousand years to evolve adaptability to high CO2 concentrations. They have had only 150 years so far to adapt to rising CO2 levels, and will have 100 to 150 more at most given BAU to adapt to levels which are currently severely damaging. The only way populations can evolve that fast is by crashing, ie, to reducing down to the very few individuals that may be currently tolerant, and then gradually rebuilding population levels. The problem with this approach is that if a population crashes, there is no guarantee that it will rebuild. Indeed, given the results discussed in the article above, many species of fish may be on their way to extinction, and possibly many regions of the Oceans will become fish free for perhaps centuries (if we are lucky) or millenia (if we are not). That is not guaranteed to happen, but it is a realistic possibility on current data. The contrast with natural changes in CO2 levels is that the large changes have occurred over millions of years, thereby giving animal species time to evolve new traits and to adapt to the new conditions. If we also where raising CO2 levels at a rate of 1 ppm per millenium or less, than we to would have little to worry about in terms of biological adaption. On the other hand, when nature has caused CO2 levels to rise rapidly (on 10 thousand year time scales) wide spread extinctions have always occurred. Given that we are raising CO2 levels at 100 times that rate (and 10,000 times the normal rate of natural change), we have no reason for confidence.
  36. Ocean Acidification Is Fatal To Fish
    Thanks JohnBruno, I'm just a bit lost as to what this article is trying to tell us. If the climate had never changed, we'd still have dinosaurs. Obviously, when conditions change, some species die, some flourish. I don't know what the point of this scientist was killing fish just to point out the bleeding obvious. What's his next experiment, setting fire to a cat?
    Response:

    [DB] "Obviously, when conditions change, some species die, some flourish."

    Your concerns are better addressed on the Climate's changed before thread.  Please avoid statements such as your last, which adds nothing to the dialogue and is largely interpretable as trolling.

  37. Roy Spencer on Climate Sensitivity - Again
    Tom, do you think that in a nontechnical press article that people are going to realize that "corrections" means "journal article" or are they going to read that "[Santer] and other researchers contacted for this column noted that there have been several instances when Christy and Spencer have had to correct their datasets for factors such as changes in satellite orbits over time, and with each correction the data has come into better alignment with surface warming and model projections." (right below the figure noting the "corrections") I realize that the WashPost article is ambigious since it also says "Santer's recent study found that the warming seen in the UAH dataset is unlikely to be the result of natural variability alone." Thanks for quantifying the correction versus the trend. That's something that should have been done all along.
  38. Ocean Acidification Is Fatal To Fish
    mace @ 20: If you had a giant time machine and transported all of the extant (google it) fishes to the Cambrian, most would go extinct. The fact that life existed in the past when the land and seas were very different does not mean there would/will be no effect on life if we recreate those conditions today. Cambrian species evolved to exist in a Cambrian world, extant species aren't.
  39. Ocean Acidification Is Fatal To Fish
    mace @ 19: We still have fish, but none of the species we had 510 million years ago. They all went extinct due to environmental change, negative interactions with other species, etc. Nobody is arguing that anthropogenic climate change will completely exterminate life on the planet. Acidification might not even cause the species used in the experiments Rob described to go extinct. However, based on the results, their populations would likely be reduced, greatly. Steve L @ 17: Great question. This would be really hard to tease out with this system and some of the variance is surely non-genetic experimental noise (or demonic intrusion). I am working with two colleagues here at UNC to look at this with coral, which, due to their clonal nature, we can fragment to create a large number of replicates of the same genotype that we then expose to different temperature and pH treatments. (the small colonies of the same genotype are called "ramets") We just completed an experiment, and when analyzing the data will look for genotype by environment interactions, essentially testing if different genotypes reacted more strongly (or more weakly) to the experimental treatments. To do all this, you need to expose the same genotype (with replication) to multiple treatments - hard to do with most vertebrates unless you have a model system like mice with inbred lines in which there is little genetic variance among species. I suspect we will find variance for response to pH, but that doesn't necc. mean populations will be abale to evolve adaptively without costs, due to tradeoffs, etc.
  40. Ocean Acidification Is Fatal To Fish
    http://en.wikipedia.org/wiki/Cambrian Useful source of info. During period that fish first emerged, the global mean temperature was 7C above anomoly and CO2 was 4500ppm (more than 10 times present day).
    Response:

    [DB] See the response to your previous statement.

  41. Ocean Acidification Is Fatal To Fish
    Hi guys, another great post. I'm having a little difficulty understanding this, however. Fish first emerged about 510 million years ago, and we've had warming periods much greater than present day (up to 7C anomaly at the highest extreme) since then. As we know CO2 is correlated with global warming, we know that CO2 must have been at much higher levels than 1000ppm during those periods of high temperature. Yet we still have fish.
    Response:

    [DB] You are missing the fundamental point that the rate of change is the issue with today's human-induced climate change.  The rate of CO2 injection into the atmosphere is more than 10x that which occurred during the PETM, the most comparable period in Earth's history.  And, as you point out, CO2 is correlated with global warming (and cooling).

    Please read the CO2 Currently Rising Faster Than The PETM Extinction Event thread.

  42. Ocean Acidification Is Fatal To Fish
    For the commenters having trouble accepting that OA is a problem, I can recommend this booklet. It was the work of 160 marine scientists.
  43. The Media & Global Climate Science Communication
    oneiota – you confirm what is in the article but Media Watch gives an insight into “climate science coverage”. “There has been no equivalent studies done covering the radio and television media but from observing their output on climate change policy a similar result could be extrapolated”.
  44. The Media & Global Climate Science Communication
    And of course the printed media is not the only offender in Oz.....the airwaves have their stalwarts of distortion as well as "exposed" by the Australian ABC's Media Watch. The threads of misinformation are woven closely.
  45. Roy Spencer on Climate Sensitivity - Again
    Tom @40, I know time is an issue, but I encourage you to please do that.
  46. Roy Spencer on Climate Sensitivity - Again
    Addendum, looking through the UAH readme file, I have found more positive corrections not reported in the above chart and not included in the calculations I performed. I may produce a more accurate record later if I have time and interest.
  47. Roy Spencer on Climate Sensitivity - Again
    Eric (skeptic) @38, I believe you are over interpreting the graph's title. The graph does indeed show corrections to the "University of Alabama-Huntsville temperature record over time". Every data point, except the most recent is a journal article reporting a correction. The articles are presented so as to show the reported trend for each journal article. It is true that as presented in the blog, the graph invites your misunderstanding, which is a problem. However, it is certainly not clear that the problem lies in the graph, which as originally produced and presented by Abrahams may well have explained the issue we are discussing. Taking a different approach to that issue, I have just come across this figure detailing corrections to the UAH record: (h/t to Eli) Together with the correction of 5th Dec 2006 (listed here, they sum to a total correction of + 0.079 degrees C per decade, ignoring some minor corrections whose effects are not given. That means by Spencer and Christy's own account, corrections represent 39% of the total change in reported trend from 1994 to 2011. Adjustments post 97/98 El Nino amount to 0.049 degrees C per decade, meaning the El Nino itself contributed 0.052 degrees C of the trend in 2000. That is, the 97/98 El Nino, which Spencer and Christy call the largest effect, is approximately equal in effect to adjustments since 1998, and less in effect than total adjustments which they consider not worthy of mention. I need only add that the significance of the 97/98 El Nino declined with time given the warm years that followed.
  48. Ocean Acidification Is Fatal To Fish
    Great post. I'm impressed with the apparently high variance among larvae in damage (Figure 4). It would be useful to find out how much of this was additive genetic variance, and therefore learn something about potential of populations to evolve in response to this stressor as it worsens.
  49. Roy Spencer on Climate Sensitivity - Again
    Tom: you are mostly correct, although the jump in trend after 98 "tilted the trend to be much more positive after that date." as Christy claims. But you are right that the trend after that should have decreased if "... little or no additional warming" since 1997 is a correct claim. It is clear that the 1997 claim is not correct looking at trends. Assuming that Christy is misleading in that latter claim, it still does not justify using the label on the graph in #27 which I quoted in #36. It is not possible to say that the label is correct given the jump in 1998, the start of trending in 1979, and the relative flatness in the 80's. What would make the label correct is saying it applies post 1998 or something along those lines.
  50. Roy Spencer on Climate Sensitivity - Again
    Eric (skeptic) @36, using current UAH data, the trend from 1979 to 1997 is positive, whereas in 1998 UAH showed it as negative. The difference is such that around half difference between C&S 1998 and CS&B 2000 is a result of corrections, and so it is not true that, as Christy would have it:
    "The major result of this diagram is simply how the trend of the data, which started in 1979, changed as time progressed (with minor satellite adjustments included.) The largest effect one sees here is due to the spike in warming from the super El Nino of 1998 that tilted the trend to be much more positive after that date."
    Further,on their current product, the trend from 1979 to 2002 is less than the trend between 1979 and 1999. Therefore that 0.03 C/decade increase in the trend is entirely due to adjustments. In all, based on a visual inspection of this graph, around three quarters of the total increase in trend over time is due to adjustments. Attributing the "major result" of the diagram to being "...simply how the trend of the data ... changed as time progressed" is a substantial misstatement. Further, if there had been "... little or no additional warming" since 1997 as Spencer and Christy maintained in their press release, then the trend would have declined gradually after 1997 as the years lengthened but the temperature did not increase. In other words, if their statement in the press release had been true, the trend for 2011 would have been less than that reported in 1998, with any difference being the result of adjustments. Being generous, the decline in trend should follow the result reported in 2000, meaning that if their press statement was correct, and their criticism of Abraham's graph were also true, the current UAH trend should be 0.05 C/decade or less. This constitutes a major contradiction between their two statements, and is not reconcilable as an honest mistake. If they thought a week ago that the data indicated no increase in the trend after 1997, then one weeks data cannot have justified a switch to the position that most of the increase in trend since then has been the result of warming. If, on the other hand, the claim that the increase in trend since 1997 reflects the data rather than adjustments is their honest opinion, they cannot also have believed just one week ago that there has been "... little or no additional warming since then".

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