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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 51751 to 51800:

  1. Global Surface Temperature: Going Down the Up Escalator, Part 1
    Current satellite data (Icesat, Grace, Jason..) would seem to suffer from some imprecision (1+ mm/yr), hence the proposed GRASP mission (it is marvelous to see the detail that goes into these projects) http://ilrs.gsfc.nasa.gov/docs/GRASP_COSPAR_paper.pdf
    Thus, we assess that current state of the art reference frame errors are at roughly the mm/yr level, making observation of global signals of this size very difficult to detect and interpret. This level of error contaminates climatological data records, such as measurements of sea level height from altimetry missions, and was appropriately recognized as a limiting error source by the NRC Decadal Report and by GGOS.
    This is all heading in the right directions, but it seems to me at this stage it still leaves us with a cycle of interdependent adjusted data: OHC/TSL/TOA.
  2. Global Surface Temperature: Going Down the Up Escalator, Part 1
    Markx, you seem to be going on an adjustment binge. Perhaps before questioning yet more adjustments you should describe in detail the basis of your doubts, keeping in mind that "I doubt it" is not an argument?
  3. Global Surface Temperature: Going Down the Up Escalator, Part 1
    ...interesting to note that the errors in the Argo data were detected due to mismatching with Ceres TOA data. I'd be interested in seeing a reference for that. Pointer?
  4. Global Surface Temperature: Going Down the Up Escalator, Part 1
    scaddenp at 14:42 PM on 4 November, 2012 "...the claim passes the "sniff test" - the OHC increase is consistent with thermosteric sea level rise...." In addition to above posts, satellite TSL rise itself is not matching OHC as calculated from known measurements. But is there a really tight agreement between calculated and TSL, measured OHC and TOA? It seems to me all require adjustments, partially based on each-other. GEOPHYSICAL RESEARCH LETTERS, VOL. 32, L12602, 4 PP., 2005 doi:10.1029/2005GL023112 Thermosteric sea level rise, 1955–2003 Antonov Levitus Boyer
    For the 1955–2003 period, the thermal expansion of the 0–700 m layer of the World Ocean contributed approximately 0.33 mm/year to global sea level rise. About half of this thermosteric trend is due to warming of the Atlantic Ocean. Approximately one third of the total thermosteric rise is due to the warming of the Pacific Ocean. For the period of available TOPEX/Poseidon (T/P) satellite altimetry data (1993–2003), the linear trend of thermosteric sea level (0–700 m) is 1.23 mm/year, 60% of which is due to the trends in the Pacific Ocean. For the 0–3000 m layer of the entire World Ocean, the linear trend of thermosteric sea level is 0.40 mm/year for 1955–1959 through 1994–1998.
  5. Global Surface Temperature: Going Down the Up Escalator, Part 1
    Rob Painting at 05:53 AM on 4 November, 2012 "....Virtually all datasets require corrections. Until such time as humans invent a perfect measuring instrument, it's something we have to live with..." Agreed. It was interesting to note that the errors in the Argo data were detected due to mismatching with Ceres TOA data. Of course, Ceres data is also adjusted, to match modeled TOA expectations. I respect and admire the detail these scientists go to to monitor, analyze and correct such data. But I cannot help but wonder about corrections piled on adjustments, and I appreciate the chance to discuss this. Loeb etal 2009 ‘Toward Optimal Closure of the Earth’s Top-of-Atmosphere Radiation Budget’ J. Climate, 22, 748–766
    This study provides a detailed error analysis of TOA fluxes based on the latest generation of Clouds and the Earth’s Radiant Energy System (CERES) gridded monthly mean data products [the monthly TOA/surface averages geostationary (SRBAVG-GEO)] and uses an objective constrainment algorithm to adjust SW and LW TOA fluxes within their range of uncertainty to remove the inconsistency between average global net TOA flux and heat storage in the earth–atmosphere system.
  6. Hurricane Sandy and the Climate Connection
    Physics, yeah. The challenge of physics here is how to vanish astounding amounts of extra energy, even the little proportion that isn't being sponged up by the ocean. A thorny problem. Hurricanes are giant heat engines but the hypothesis is they'll be prevented from feeding on additional available heat to do more work. All hurricanes will obey the new paradigm? The hypothesized mechanism to stop hurricanes from exploiting a more energetic environment will always work? Color me "ignorant" but that doesn't sound very likely. Also, what does an obedient hurricane look like? If a hurricane has followed the plan and is shrugging off the opportunity to be more kinetic but is only coincidentally the largest ever in its region what's the diagnostic of the obedience, the fingerprint of "normal?"
  7. Hurricane Sandy and the Climate Connection
    Dikran Marsupial at 21:10 PM on 4 November, 2012 "..... Note that in this case the observations are not the only line of evidence, there is also physics (as Trenberth amongst others points out)...." Indeed in agreement with Trenberth: http://www.livescience.com/24377-weather-climate-hurricane-sandy.html :
    In general, we estimate it increases the risk that the intensity of hurricanes can be somewhat greater and particularly the rainfall from hurricanes is about 5 to 10 percent greater than it otherwise would be,” Trenberth said. In the case of 2005′s Hurricane Katrina, which dumped at least 10 inches (25 centimeters) of rain along its track on the Gulf Coast, that means about 1 inch was attributable to climate change, Trenberth said. Sandy could dump similar levels of moisture over the Northeast. Trenberth added that “there are signs” that storms of Category 3 and above are becoming more common, but warned that hurricanes show tremendous natural variability from year to year, driven largely by climate patterns set up by El Niño.
  8. The View from Germany: Tackling the real questions
    Oops-- Guinea, not Ghana. Same insolation so no biggie. :-)
  9. The View from Germany: Tackling the real questions
    The frequently touted reduction of electricity consumption via conservation and efficiency hardly matters if you have a low carbon electricity supply. Hmm. I don't mean to sound contrary but my nephew in-law is currently in Ghana w/the Peace Corps and has been existing w/a ~3W solar panel for about a year now. This provides light to read and cook by and keeps his phone charged but he does not leave the light on all night or his phone switched on. Efficiency absolutely matters, always.
  10. The View from Germany: Tackling the real questions
    Well explained quokka. Yes we must of course work on decarbonizing transport. And again I draw the attention to France , where the Auto- Libe car share / hire scheme started operating last year. It is essential though that the car batteries are charged with zero emission electricity, which in France means nuclear. All I meant to say is that it is possible to make significant reductions in Co2 emissions, with proven and existing technology, without necessarily wrecking civilisation as we know it.
  11. The View from Germany: Tackling the real questions
    @doug_bostrum, Yes, it is in some ways depressing and indicative of the difficulties of getting to where we need to be. France's emissions in electricity generation are about 85g CO2/kWh. Going substantially lower than that without lots of hydro would be really difficult, and the only nations that do beat that are in fact those with lots of hydro. I would think that relative difference between France and Germany's emissions are representative of what can reasonably be expected by decarbonizing electricity supply in an industrialized western nation with some variation depending on national characteristics. As for decarbonizing other sectors such as transport, the outlook is bleak with little substantial action other than perhaps some improved fuel efficiency. The frequently touted reduction of electricity consumption via conservation and efficiency hardly matters if you have a low carbon electricity supply. Take the example of Sweden with lower emissions than France but huge electricity consumption. Nuclear+hydro is the key there. Ultimately a low carbon electricity supply at low cost is the key as the only reasonably plausible path to decarbonizing other sectors is maximum electrification.
  12. 2012 SkS Weekly News Round-Up #8
    Regarding "Crippled NY subways spark infrastructure, climate questions" article, with a quote about making NYC subways water-tight: "[it would be] engineering feat equal to the scale and creativity of the original construction" That's an interesting point, because it looks to me that crippled subways contributed very large (if not largest) chunk of Sandy's damage bill. And growing as the service restoration time is still unknown... But how about this news: Inflatable Plug Could Have Stopped NYC Subway Flooding It's important, because for me, it looks like subways are the weakest link of NYC infrastructure. Does anyone find this plausible/reasonable to implement? Or NYC subways will be eventually inundated forever, as we can expect Sandy-like storms every 2 years now? Unless they find something to hold water off, they won't be able to repair this sort of damage every two years and must eventually abandon the system...
  13. The View from Germany: Tackling the real questions
    Maybe "surprised" would be a better word than underwhelmed. Mystified also; given the mix of electrical generation capacity in France, what sector is propping up C02 emissions to that extent? I was expecting something more dramatic. It's actually a pretty depressing statistic considering France has effectively squeezed hydrocarbons (particularly coal) from their mix to the point HC combustion is only about 1/10th of French generation capacity.
  14. The View from Germany: Tackling the real questions
    That should be page 29. Also important in making comparisons is energy use per capita. Germany and France have almost identical Energy Use per Capita, though France's electricity consumption per capita is higher.
  15. The View from Germany: Tackling the real questions
    @doug_bostrom The latest figures I could locate are for 2011 are: Germany 9.9 tonne CO2 /person France 5.7 tonne CO2 /person Which by my calculation makes Germany's per capita emissions 73% higher than those of France. Trends in Global CO2 Emissions page 27. I would not call that underwhelming.
  16. James Hansen's Motivation
    Bill, can you clarify please? Paleocene is 55-65myr ago. No methane proxy. Can I assume you mean Pleistocene? Carbon isotope studies have looked at methane signature in ice bubble data. Indications to date are that methane source is not benthic hydrates nor boreal peatland(eg Petrenko et al. (Follow cites for other studies). Less consensus on what the methane sources actually are (swamp, burning, lakes etc).
  17. The View from Germany: Tackling the real questions
    I think Uncle Pete's point is that per capita C02 emissions in France are lower than Germany's. That said, the difference seems underwhelming:
  18. The View from Germany: Tackling the real questions
    Pete @16: What is your case?
  19. citizenschallenge at 08:17 AM on 5 November 2012
    Rose and Curry Double Down on Global Warming Denial
    {Doug B @49 Thanks great list!} ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ My little "Curry's No Consensus On Consensus - Challenged" is still a work in progress, so when I can I reread and refine. I want to share today's rewrite of paragraph one's review. cheers citizenschallenge =============================================== Judith Curry writes: ¶1)  The manufactured consensus of the IPCC has had the unintended consequences of distorting the science, elevating the voices of scientists that dispute the consensus, and motivating actions by the consensus scientists and their supporters that have diminished the public’s trust in the IPCC. ================================================= re: ¶1 ~ ~ ~ ~ ~ ~ ~ JC: "manufactured consensus of the IPCC has had the unintended consequences of distorting the science..." <<< That is an incredibly big and damaging charge. Where is Curry's evidence!? Specifically what topics have the IPCC distorted? Why no list? Where is Curry's examination comparing the scientific community's assessments  with the IPCC's manufactured and published "consensus"? Where does Curry outline and review the many meetings and conferences and writings and back and forth communication that goes on during this IPCC manufacturing process? Why make the base assumption: 'IPCC's all sinister'? {Just because the news is bad for big business?  I thought this was science we were discussing?} The IPCC is actually a small organization tasked with compiling the available legitimate science.   Curry doesn't seriously examine who the IPCC are; what they have been legally tasked with doing; and how they have gone about their task.   ~ ~ ~ ~ ~ ~ ~ JC: "... elevating the voices of scientists that dispute the consensus..." <<< What is Curry talking about?   What's it supposed to mean?   What point is Curry trying to weave into her story here? ~ ~ ~ ~ ~ ~ ~ JC: "... and motivating actions by the consensus scientists..." <<< Scientists read and talk and meet on all sorts of different levels.  There are seasons and politics just as in every other professional endeavor.  But, it's still a serious organization with a planned process, openly established and openly conducted, and it's produces reports on the state of the science.  Fair and square. ~ ~ ~ ~ ~ ~ ~ JC: "have diminished the public’s trust in the IPCC." <<< You won't find anything here about Seitz and Singer and the tactics of manufacturing doubt? Why not examine the various dirty tricks and PR tactics that have targeted the IPCC and climatologists in general? Why not ask if there's evidence this "diminished pubic trust" was the product of a manufactured publicity campaign? ================================================= Here's some evidence: The American Denial of Global Warming -  Perspectives on Ocean Science Series: "Perspectives on Ocean Science" [12/2007] [Science] [Show ID: 13459] Uploaded by UCtelevision on Dec 20, 2007 =============== A Merchant of Doubt attacks Merchants of Doubt by Naomi Oreskes and Erik Conway
  20. James Hansen's Motivation
    In his TED talk, Hansen showed graphs of temperature, carbon dioxide, and sea level during the Paleocene. He did not show the methane graph. He said (1) that carbon dioxide lags temperature by a couple thousand years; (2) that deniers use this fact to allege that warming increases carbon dioxide, not vice versa; (3) that, the climate change is in fact initiated by orbital changes [Milankovitch theory] and is accelerated by positive feedbacks, which include carbon dioxide released from the warming oceans as from a warming Coke. In contrast to carbon dioxide, methane leads temperature by about a thousand years in the Paleocene record. It would therefore seem that atmospheric methane was the initial accelerator of climate change and that the later increase of carbon dioxide included not only carbon dioxide coming out of solution in the oceans but also methane oxidized to carbon dioxide in the upper atmosphere. Carbon dioxide levels comparable to current levels are essentially nonexistent in the Paleocene record (industrial emissions of carbon dioxide did not exist then). We face a reasonable probability of major methane releases from thawing permafrost and from benthic methane hydrate desposits. For me, this adds to the urgency of Hansen's admonition.
  21. Hurricane Sandy and the Climate Connection
    Dhogaza at #76. I too appreciate your analogy. I hope you don't mind if I shamelessly plagiarise it in future posts!
  22. Papers on Hurricanes and Global Warming
    Probably relevant within context: Modelling sea level rise impacts on storm surges along US coasts [abstract] Claudia Tebaldi et al 2012 Environ. Res. Lett. 7 014032 doi:10.1088/1748-9326/7/1/014032 Tidally adjusted estimates of topographic vulnerability to sea level rise and flooding for the contiguous United States [abstract] Benjamin H Strauss et al 2012 Environ. Res. Lett. 7 014033 doi:10.1088/1748-9326/7/1/014033
  23. Dikran Marsupial at 21:10 PM on 4 November 2012
    Hurricane Sandy and the Climate Connection
    Just to be clear, the lack of a statistically significant trend does not mean that no trend is detected, it means that the possibility of there being no trend cannot be ruled out with high certainty (loosely speaking). However the real reason that AndersMi's argument is silly is because it is a straw man. Nobody AFAICS is arguing that climate change is the cause of this storm, but that climate change influences the intensity of storms. Note that in this case the observations are not the only line of evidence, there is also physics (as Trenberth amongst others points out). This suggests that the lack of statistical significance may be due to the test having low power, rather than the null hypothesis actually being true (i.e. you would expect not to see a statistically significant trend even if the null hypothesis is false).
  24. Hurricane Sandy and the Climate Connection
    @59 Albatross, I'm looking forward to what you can unearth. I've been scouring Google Scholar and other websites for more homogenous info regarding wind fields and sizes for historic hurricanes, but cannot come up with much. I would like to read the following study but cannot find a copy online: "Dunnavan. G. M. and Diercks, J. W. 1980. An analysis of super typhoon Tip"
  25. 2012 SkS News Bulletin #1: Hurricane Sandy & Climate Change
    markx - this is straying far the topic of this thread. I have instead responded to you here which I think is more appropriate before moderators start removing posts as offtopic.
  26. Hurricane Sandy and the Climate Connection
    Dhogaza - that's a most vivid analogy - thanks for posting! AndersMi, you need to examine in turn the factors that initiate, drive/inhibit, steer and multiply the effects of hurricanes in the North Atlantic and consider how these parameters may be affected by a system containing more energy. Such factors including variations in sea surface temperatures, convective instability in the tropics, deep-layer shear throughout the entire area, likewise atmospheric circulation patterns, changes in sea level and so on. These vary from basic physics based on observations over many years to new emergent properties (e.g. atmospheric responses to very rapid - compared to predictions - meltdown of Arctic sea ice). Some of these factors (e.g. shear profiles) may well change in ways that might inhibit developing storms (then again they may go the opposite way), but it is worth noting that Sandy ploughed straight through a zone of fairly high shear quite merrily on its way to landfall. Just one of the meteorologically-interesting features of the storm. Another was its explosion in energy during barotropic to part- and then fully-baroclinic transition. Baroclinic storms thrive in high-shear environments and these two features may well be related.
  27. CO2 limits will harm the economy
    Responding to Comment here markx - "equitable" <> "equal". What I means is that most of the extra carbon in the air is from the west. Other countries need to emit to grow their economies while the west has the wherewithal to decarbonise. I would also notice that in the west, it is predominantly the rich convervatives on the right that deny climate change and resist calls for decarbonising. Mind you a carbon-tax on the border would ensure that exporters to the west would rapidly look for ways to decarbonise too. Let the market work its magic.
  28. The View from Germany: Tackling the real questions
    Taken from the IEA monthly electricity stats archive are some figures on German electricity production. The first number is the production by combustible fuels, the second is total electricity production. Units are GWh. 2005: 372,086/581,251 2006: 354,871/569,943 2007: 388,834/584,939 2008: 380,334/607,286 2009: 357,134/571,397 2010: 374,080/580,849 2011: 354,178/551,348 In the period Jan-July 2012 electricity production by combustible fuels was up 4.2% on the corresponding period in 2011. Total production was up 3.5%. The situation appears approximately static. Assuming that combustible fuels includes biomass, the situation should be a little better than the figures indicate at first glance. But that also raises environmental concerns over the large scale use of agricultural biogas, it's carbon footprint and issues of scalability. Claims that Germany does or will show it is possible to do without nuclear and fossil fuels have a long way to go before they could be proven. Most likely decades and that is far too long. This is not an anti-renewables comment, it is a pro arithmetic comment.
  29. 2012 SkS News Bulletin #1: Hurricane Sandy & Climate Change
    markx - now you are talking about politics and that’s our biggest problem because it is corrupted by the existing energy generation “establishment”. I didn’t say this was going to be an easy transition. I bought solar panels two and a half years ago, and since then their power output has nearly doubled, while the price has nearly halved. It took coal generation 150 years to reach current efficiencies, so solar is still in its infancy. There are only a handful of base-load solar power stations so far so they have yet to reach economies of scale. “- like on your roof for one”........ so I wasn’t just talking about solar. There’s plenty more renewable energy sources that haven’t reached anywhere near their potential, and some we haven’t heard of yet. By the way, it will probably be China that develops them.
  30. 2012 SkS News Bulletin #1: Hurricane Sandy & Climate Change
    scaddenp at 14:35 PM on 4 November, 2012 "...An equitable solution would be decarbonise the west so other countries can grow without damaging the climate...." Not so simple really - I'm forever dealing with incredibly rich individuals and businesses in China - the wealth is astounding. And no doubt there are huge numbers of poor there, but such people also exist in western countries. So perhaps it is inevitable that any 'carbon trading scheme' will require a huge social engineering program, redistributing cash (the poor's energy needs are fixed - reduce energy usage and someone will go hungry or cold).
  31. 2012 SkS News Bulletin #1: Hurricane Sandy & Climate Change
    Brian Purdue at 10:45 AM on 4 November, 2012 "...We have to think local for our energy supply – like on your roof for one...." I agree entirely with you on that Brian. But I think you will find big business still has it's way in the end - governments much prefer centralized business control (purposes of tax, monitoring, QC, control, regulation). In some areas of Australia there are already limitation as to the number of solar cells you may put on a household roof (and anyway solar cells are not so far living up to the sales talk). Even solar hot water is over regulated, mainly because somewhere in the system you must have connections to a public supply system... and there is no hope of avoiding that as in some areas you cannot even catch the rain which falls on your roof - "they" want to catch it a sell it to you! ... with similar legislation for use of stream or underground water. (becoming fully a commercialized commodity.)
  32. Global Surface Temperature: Going Down the Up Escalator, Part 1
    Markx, at the moment, you are making a claim from Personal Incredulity. Perhaps it would be best to start with the actual papers that make the claims and fault their logic instead? But as Doug points out, the claim passes the "sniff test" - the OHC increase is consistent with thermosteric sea level rise.
  33. 2012 SkS News Bulletin #1: Hurricane Sandy & Climate Change
    If someone is going to play the "China" card then its worth noting that China is also retiring older inefficient coal plants; that the energy demand in the China is largely to supply goods to the west - in effect the West is exporting emissions to China; and that per capita energy use in China is far below that of USA. The emissions causing trouble in our atmosphere at the moment are from western emissions over the last 100 years, not Chinese. An equitable solution would be decarbonise the west so other countries can grow without damaging the climate.
  34. Hurricane Sandy and the Climate Connection
    If size of storm surge is a good proxy for intensity,(and since this proxy avoids observational biases in other measures)t then the Grinsted paper does find statistically significant correlation between temperature and intensity.
  35. Hurricane Sandy and the Climate Connection
    As so often happens, a denier is pulling the thread completely off track be presenting a vacuous argument, and then sticking to it no matter what, so that everyone finds the need to argue with him. Meanwhile, the original point of the post (that the fingerprints of climate change can be found all over this particular extreme weather event) is lost under silly arguments about what a trend is, what the trends say, how they apply, etc. If the argument actually had any merit, that would be one thing. But it doesn't. It's just another hardcore-denier pretending that there is no evidence, when the evidence is slamming his head over and over into a brick wall saying "can you hear me now?"
  36. 2012 SkS News Bulletin #1: Hurricane Sandy & Climate Change
    markx, you neglect to mention the mining of the coal. This is obliterating the landscape, poisoning the air and water, and destroying the health of the surrounding population along the way. A lot of the coal has to be transported halfway around the world by truck, rail and ships, which uses up oil reserves and damages the environment in the process. We have to think local for our energy supply – like on your roof for one.
  37. Hurricane Sandy and the Climate Connection
    AndersMi, you're confusing a lack of statistical significance with a lack of trend. The two are not the same. A dataset can have a strong apparent trend that has not quite enough datapoints to reach a desired level of significance. This does not mean that there is no trend. Your kind of fallacious argument has often been used in evaluating short-term global temperature trends- a trend of +0.010C/yr +/- 0.012C is nonzero and not quite statistically significant. Failing to reject the null hypothesis does not mean you unconditionally accept the null hypothesis.
  38. Hurricane Sandy and the Climate Connection
    "As for my "silly argument". No statistically significant increase doesn't mean, as you say, "an uncertainty in the magnitude of the increase". It means no increase detected." I'm sorry, but this is simply wrong. One can detect an increase that doesn't reach statistical significance, which is commonly meant to mean that the computed trend reaches the 95% confidence level. A[n] [in]famous example was the "no statistically signifcant trend since 1995" comment twisted into "no increase detected" by denialists. Actually, at the time the statement was made, the significance level was > 90% but < 95%. If you think this means "no increase detected", let me hand first hand you a revolver with 100 chambers, 95 filled with cartridges, and then one with (say) 92 cartridges. If you have faith in your interpretation you'll gladly play russian roulette with the second, because it is "empty" while the first is "full".
  39. Hurricane Sandy and the Climate Connection
    Tom, thanks for your long and interesting reply. I take the first of your quotings from SREX as supporting the lack of certainty over the presumed trends (the Webster et al. paper is dated 7 years earlier than the SREX report and has been certainly weighted in). The fact that the lack of confidence in the trend has to be attributed to a small number of new events or in the uncertainty in the actual number of old ones, is frankly irrelevant. And if overall this doesn't tell us that there is no trend, as Dana1981 rightly remarks, it suggests that the global warming signal, if there is any, must be difficult to single out. The new Grinsted et al paper is certainly interesting and I didn't know about it. Let's see whether its findings will be confirmed by other studies. As for my "silly argument". No statistically significant increase doesn't mean, as you say, "an uncertainty in the magnitude of the increase". It means no increase detected. If you can't detect changes in events on a statistical scale, how can you blame a single instance on a specific cause? Not only you would need an absolute certainty on the causation mechanism, and on the fact that in different conditions the event wouldn't have realized - which you don't and can't have in this case; but you also need to justify why this causation mechanism doesn't show its signature with a detectable statistical trend, that is, why doesn't it happen *repeatedly*. You're like somebody claiming that a tumour was caused in a patient by a particular chemical substance, although there is no statically significant increase in tumours in populations subject to that same substance.
  40. Philippe Chantreau at 09:10 AM on 4 November 2012
    Global Surface Temperature: Going Down the Up Escalator, Part 1
    Markx says ""I worry at the statistically calculated precision over a 55 year period from data which itself has required corrections." Looking a the loss of Arctic Sea ice, loss of permafrost, extreme weather events, rising sea levels, extreme storm surges, I am of the opinion that there are other things to "worry" about.
  41. The View from Germany: Tackling the real questions
    http://www.ucsusa.org/global_warming/science_and_impacts/science/graph-showing-each-countrys.html This is a graph of Co2 emissions by various countries. Please note the difference between Germany and France. I rest my case your honour.
  42. Hurricane Sandy and the Climate Connection
    AnderMi has variously conflated "low confidence" in the SREX report with lack of statistical significance (they are not the same), and quoted summary results on global statistics as though they are representative of observations in the North Atlantic. In fact, the SREX says this of the North Atlantic (p 159, PDF):
    "Regional trends in tropical cyclone frequency have been identified in the North Atlantic, but the fidelity of these trends is debated (Holland and Webster, 2007; Landsea, 2007; Mann et al., (2007a). Different methods for estimating undercounts in the earlier part of the North Atlantic tropical cyclone record provide mixed conclusions (Chang and Guo, 2007; Mann et al., 2007b; Kunkel et al., 2008; Vecchi and Knutson, 2008)."
    Webster et al (2005) (PDF) says of the North Atlantic:
    "Figure 3 shows that in each ocean basin time series, the annual frequency and duration of hurricanes exhibit the same temporal characteristics as the global time series (Fig. 2), with overall trends for the 35-year period that are not statistically different from zero. The exception is the North Atlantic Ocean, which possesses an increasing trend in frequency and duration that is significant at the 99% confidence level. The observation that increases in North Atlantic hurricane characteristics have occurred simultaneously with a statistically significant positive trend in SST has led to the speculation that the changes in both fields are the result of global warming (3)."
    So, the trend in North Atlantic cyclones (Hurricanes) is statistically significant, contrary to Andermi's clear suggestions. The validity of that trend, at the time of the SREX had "low confidence" not because the data do not show a trend, but because it is unclear whether the data accurately reflects the frequency of hurricanes in the early part of the record. That lack of confidence is no longer warranted. Grinsted et al have used long records of consistent quality to establish that Hurricanes are twice as likely in warm years as in cool years. The connection between increased temperature and increased frequency of Hurricanes in the North Atlantic must therefore be considered well established. (Note: although Grinsted et al show a positive trend in US land falling tropical storms, and in Accumulated Cyclone Energy, those trends are not statistically significant in large part because the record starts in the relatively warm 1930s.) Turning to AndersMi's frankly silly argument, he says:
    "So, since there is no clear statistical increase of storms, it follows that if we can prove that some storms are indeed caused by global warming, then some others must be disappearing to keep the observed balance even. Otherwise we would see an increasing trend, which we don't."
    Leaving aside the fact that his premise is false of the North Atlantic, the implied argument is nonsense. He equates "no statistically significant increase" with no increase. That is, he assumes uncertainty about the magnitude of the increase implies certainty that there has been no increase. Assume the increase in tropical cyclones since the 1950s was 5 +/-10 per annum. Then there would have been no statistically significant increase. We would not know from that fact, plus the fact that one particular cyclone was caused by global warming that the increase was in fact zero, and that therefore a potential cyclone was caused to dissipate by global warming.
  43. Hurricane Sandy and the Climate Connection
    Anders @72 - as I noted @70 and as I believe others have noted as well, inability to detect a statistically significant trend due to a large amount of noise does not mean a trend doesn't exist.
  44. Global Surface Temperature: Going Down the Up Escalator, Part 1
    I note that the graphical representation of the data from Levitus 2012 shows approximately 50% data coverage down to 2000 m up to the end of the time series shown. I suspect, given additional papers discussed in this Skeptical Science post, that improving the coverage would not favour the claim that the oceans are cooling.
  45. Hurricane Sandy and the Climate Connection
    Moderator and dana1981: as I've already written in many comments, the source for the statement "there is no clear statistical increase of storms" is IPCC's SREX report, published in March 2012. Full report, page 111: "There is low confidence that any observed long-term (i.e., 40 years or more) increases in tropical cyclone activity are robust, after accounting for past changes in observing capabilities." And more, with a slightly different nuance in the same report's Summary for Policymakers, page 6: "There is low confidence in any observed long-term (i.e., 40 years or more) increases in tropical cyclone activity (i.e., intensity, frequency, duration), after accounting for past changes in observing capabilities.". For Moderator, I'd appreciate if you'd remove from my previous comment the request to provide a source, since it suggests that I hadn't - while I alrady had in my very first comment to this post: >>----- AndersMi at 22:06 PM on 3 November, 2012 It seems to me that this post contradicts the latest IPCC report on extreme events, SREX, published in March 2012, where it says: "There is low confidence in any observed long-term (i.e., 40 years or more) increases in tropical cyclone activity (i.e., intensity, frequency, duration), after accounting for past changes in observing capabilities." >>----- For dana1981: The Knutson et al. (2010) paper has been surely taken in account in IPCC's SREX (2012). As for what Emanuel shows, it's fine, but it's model-based. Reality doesn't seem (yet) to show the signature of GW in this respect.
  46. Climate Newbie at 06:06 AM on 4 November 2012
    Hurricane Sandy and the Climate Connection
    Thanks michael sweet - it's just perplexing that he has enough time to answer the question, and to block me, and then to re-edit his answer. And erase my question. My comment and question were (and are) on this topic.
  47. Global Surface Temperature: Going Down the Up Escalator, Part 1
    Markx - Yes, with a mercury thermometer. Reversing thermometers, but it's good to see you've moved on from the ropes and buckets claim. I note you never attempted any explanation as to why you thought ropes and buckets were used to measure subsurface ocean heat. Is that a myth circulating on contrarian blogs? "It seems to be quite test of the power of the statistical analyses to take this back to 1955" The uncertainty of the analysis is shown in vertical red bars (0-2000mtrs) & grey shaded areas (700-2000m) in this figure from Levitus (2012): "I worry at the statistically calculated precision over a 55 year period from data which itself has required corrections" Virtually all datasets require corrections. Until such time as humans invent a perfect measuring instrument, it's something we have to live with. The issues with some of the ARGO floats is unlikely to side with the wishful thinking of contrarians I'm afraid. The faulty floats have a pressure sensor issue which underestimates the actual depth that they are at. This means they are taking a temperature reading colder than is actually the case, introducing a cool bias into the dataset. This issue is still being addressed, and no doubt other problems will crop up, but this is no different to any other climate-related dataset. I do note, however, that many contrarians, such as Roger Pielke Snr, thought ARGO was the greatest thing since sliced bread when it indicated the oceans were cooling. But now that ARGO confirms the long-term ocean warming trend, contrarians are falling over themselves trying to find excuses not to accept the evidence.
  48. 2012 SkS News Bulletin #1: Hurricane Sandy & Climate Change
    If China pulls off the juggling act they need to perform in order to maintain social and political stability while building a durable system it'll be quite remarkable. As Markx implies, coal is a necessary if unfortunate part of that equation but still amenable to optimization. It's the permitted longevity of the band-aid fix in the form of more efficient coal plants that's dubious, unpredictable. Brutal as it is,the Chinese government might order plants only a couple of decades old decommissioned, if that government survives, and be obeyed. Scary and fascinating at the same time.
  49. Hurricane Sandy and the Climate Connection
    Regarding hurricane intensity I recommend Knutson et al. (2010) linked in the post. They explain that there is a great deal of natural variability in hurricane intensity (and frequency), and therefore it is very difficult to discern a trend in the noise. Nevertheless, they do find a trend in the intensity of the strongest hurricanes, and the models clearly predict that they will continue to grow stronger in the future. Despite this difficulty in detecting the signal beneath the noise, as Emanuel shows (in the many links to his work in the post), higher SSTs fuel stronger hurricanes. SSTs are higher than they were in the past due to AGW, and that's the world in which Sandy existed.
  50. Hurricane Sandy and the Climate Connection
    AndersMi you have ignored the point I made. An absense of something doesn't impact the intensity of the individual events. The cause of an event that has a greater amplitude has no impact on the absense of the signal at other points. The problem I have with your statements is that you are implying a cause and effect regarding the absense of something. That is frankly absurd. It also probably breaks the laws of thermodynamics and most other phyical laws. You are confusing actual physical events and actions with mathematical human assessment of those events and actions.

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