Climate Science Glossary

Term Lookup

Enter a term in the search box to find its definition.

Settings

Use the controls in the far right panel to increase or decrease the number of terms automatically displayed (or to completely turn that feature off).

Term Lookup

Settings

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.

Home Arguments Software Resources Comments The Consensus Project Translations About Support

Bluesky Facebook LinkedIn Mastodon MeWe

Twitter YouTube RSS Posts RSS Comments Email Subscribe


Climate's changed before
It's the sun
It's not bad
There is no consensus
It's cooling
Models are unreliable
Temp record is unreliable
Animals and plants can adapt
It hasn't warmed since 1998
Antarctica is gaining ice
View All Arguments...



Username
Password
New? Register here
Forgot your password?

Latest Posts

Archives

Recent Comments

Prev  2514  2515  2516  2517  2518  2519  2520  2521  2522  2523  2524  2525  2526  2527  2528  2529  Next

Comments 126051 to 126100:

  1. What happened to the evidence for man-made global warming?
    This has been a PR disaster. I've been watching this unfold for some time, having started in our local paper (which has touting global warming conspiracy theories for years) and the problem with so-called "climategate" is that climatologists are letting the Denial community totally dominate the news. I hear talk of leaked e-mails, faked and/or altered/hidden data, politicians calling for investigations and claiming hoaxes. Honestly to the casual layman this looks really bad. Climatologists have to make the public understand, in simple terms, what's in these e-mails exactly, how many researchers are involved, what exactly the research they're talking about is, what it means, what it doesn't mean, and most importantly all the other evidence pointing to climate change. Otherwise the public is going to buy into the conspiracy theories and nothing will get done.
  2. What happened to the evidence for man-made global warming?
    "This attack on an entire field of science is unprecedented". That's true, it's never happened before. What it also means is that the climate science community has no idea how to fight back. You've allowed yourselves to be backed into a corner, while the deniersphere is pummeling you, and all you can do is cower there, covering your heads,crying and whining cuz people are being mean to you. Now I don't know about anybody else, but I'm reluctent to come to the defence of someone who isn't willing to defend themselves. Even though I have, along with a lot of other people on other websites. Then I come here and find out that I'm being lazy cuz I'm not offering an explanation with the link to this site I'm providing. I can't repeat the first thought I had when I read that,but I think you get my drift. But back to my point, you've got to start fighting back. It's not like the deniersphere isn't handing you ammo. The "hide the decline" email is a perfect example. Ann Coulter in her latest op-ed, "quoted" the email thus,"I used a trick to 'hide the decline' in global temperatures since the 1960s". This is a LIE. Why aren't ya'll screaming that at the top of your media lungs?!?!?!? This is what's out in the media, this is what regular people, people who are too concerned with how they're going to feed and house themselves and their CHILDREN, are reading. People who are looking for any reason to have one less thing to worry about. And they'll stop worrying about the things that they can't see. Like global warming. So, either start fighting back, or shut up, cuz your losing the public.
  3. What happened to the evidence for man-made global warming?
    Imo, the CRU email has little or no bearing at all for the scientifically based critics. It does not add anything of interest and it doesnt withdraw anything of interest. It's just a curious side note in the protocol. However I can understand why some get upset about it, and this is the reason why they should be upset then: A thesis (or intepretation) in science must be inferred with the excluded third: the interpretation will be held as true only after an experiment been conducted that shows that the antithesis is false. And the antithesis in this case is "global warming is due to natural variations". Such experiment has been conducted – namely in simulated climate models. These models shows only a warming trend when human released CO2 is added to the model. I have no objection against accepting the simulation results, but then it should also be made clear that the conclusion is not based on an empirical evidence but a theoretical argument. Not every scientist, in particular experimentalist and field researches, is convinced about this theoretical predictions reliability and/or want to see empirical evidence supporting the theoretical predictions. But no such empirical experiment has been made so far. This is what the scientific criticism is (or should be) about The "broad view" argument, pointing at a long list of experiment showing global temperature increases, CO2 is an greenhouse gas and CO2 level increases etc etc, is nothing else than a long list of positive confirmations to the prediction made by models. From an epistemological point of view it adds nothing weather we have one(1) or one thousand experiment if they only are positive confirmation of this prediction, there is still the possibility of something else to be the cause, unless the antitheses can be experimental established.
  4. What happened to the evidence for man-made global warming?
    Here´s another paper, based on tropical glaciers, that already shows a reconstruction remarkably similar to the multi-proxy papers (see graphs on page 15): Thomson et al 2003 TROPICAL GLACIER AND ICE CORE EVIDENCE OF CLIMATE CHANGE ON ANNUAL TO MILLENNIAL TIME SCALES http://bprc.osu.edu/Icecore/Thompsonetal-climatic-change-2003.pdf
  5. Comparing CO2 emissions to CO2 levels
    Norman wells I imagine my thinking is over simplified but it seems to me that when all fossil fuels have been exhausted,and the carbon therein released ,the Earth's atmosphere should contain approximately as much Co2 as it held when vegetable life began.Since plants were able to grow in those conditions,Earth's temperature could not have been so high that life could not be supported .Why then is there such great concern over the future effects of global warming ?
    Response: Because back when the Earth's CO2 levels were much higher than today, the solar output was also around 5% less than current levels. More on higher CO2 levels in the past...
  6. What happened to the evidence for man-made global warming?
    #2 response In many ways there should be no boundaries to where these discussions should go. Although I can understand your impatience at the distrust shown by your mystery emailer. Do you want a discussion of the papers in your article? As a biologist, Parmesan 2003 interested me. Unfortunately it's a review which means the data is actually spread over dozens of other papers. So a quick look at them shows that most of the data is generated in Europe (in many cases naturalists in the UK), a little is in N America, I have found only one reference with data in the tropics (Costa Rica). This might put a big question mark over the "global" nature of the data. Having read a couple of papers throughout and a few abstracts I note several omissions from the review. ( numbers are Parmeson's references) 36 - equates most changes with nutrient/toxin (sulphates) changes rather than temperature (can only correlate with temperature over a five year period). 40 - shows flucuations in species correlated with changes in the NAO rather than a linear change to AGW. 22 - showed only 60 (rather than 279) plants flowered significantly earlier in recent times. While this paper showed greatest correlatiopn with temperature it also noted a correlation with NAO. 43 - The Costa Rica paper, this paper spend the whole time relating species change to precipitation (mist). But I do concede, and it is this sort of thing that baffles me the most, then relates this to temperature change. Unfortunately I don't have time to look at any others but I looked at these because they represented large numbers in Table 1 or were referred to multiple times. The case that this review is "global" or that it shows the fingerprint of AGW can be questioned. Personnally I don't distrust scientists. But I'm well aware they love to extract the maximum significance from their limited data. It helps to secure journals with a higher impact factor, very important to scientists.
  7. CO2 effect is saturated
    NkThrasher, that has been done. A long time ago, and repeated with increasing precision and thoroughness right up to currently. See the post How do we know CO2 is causing warming?; in that post, look in the green "Acknowledgements" box just above the start of the Comments section. Click on the link "laboratory measurements...".
  8. What happened to the evidence for man-made global warming?
    It seems equally unfair to equate the rantings of one crazy rightwing senator with all those people who want a critical/depolitisized debate on the science. As it is unfair to say one email from one scientist represents the views/morals of the whole body of scientists. There's plenty to read here, I'm going to have to give up my day job!!! (the Hansen 2005 link seems broken)
    Response: I'll concede that Inhofe is one of the more extreme cases of global warming skepticism but he's certainly not alone in dismissing climate science. There are many examples in the media and blogosphere. One personal anecdote: I've been corresponding by email with one skeptic, having a constructive, reasonable discussion of the science. However, Climategate has him distrusting all climate scientists, effectively making any further discussion of peer reviewed science impossible.

    Thanks for the tip re Hansen 2005 - I've fixed that link.
  9. CO2 effect is saturated
    Wouldn't a much more useful test of a saturation point be, testing for a saturation point? This only seems to directly indicate that if there is such a saturation point, we haven't hit it yet, not that there is no saturation point to hit. I haven't been able to find anything to this effect, but a test in a laboratory using a similar method to observe the absorption rate of the same wavelengths passing through a chamber with various concentrations of the gasses we would expect to see in the upper atmosphere could show whether it does have an asymptotic behavior and thus 'saturates'? Just seems somewhat fishy that the logic goes "It could reach a saturation point!" "But it's still increasing as we increase the CO2, so there is no saturation point!", analogous to "If you eat too much candy you get sick!" "But I've been eating candy for the last 20 minutes and I continue to feel fine!"
  10. What happened to the evidence for man-made global warming?
    Congratulations on getting on the BBC's list of recommended blogs.
    Response: Thanks for the link, I didn't know about that page, must be hot off the press (will "hot off the server" be a phrase used by future generations?). That page is a useful resource.
  11. An overview of glacier trends
    Data: current North American Glacial Area 13080.6 sq.Km Overview of current North american Glaciation: Source: http://www.ccin.ca/cms/en/socc/currentGlaciers.aspx
  12. What do the hacked CRU emails tell us?
    And now greenman3610 has posted a video with a bit more technical detail (though with a bit less humor, unless you're a Beevis and Butthead fan).
  13. Al Gore got it wrong

    I am astounded to see point 8 ("that coral reefs were bleaching because of global warming") included as an 'error'. I'd suggest you could safely add that one to the list of what Al got right. Yes, there are other factors that cause corals to bleach, but mass coral bleaching is accepted to occur as a result of higher-than-normal sea temperatures resulting from global warming. Leaving it to the experts: "The primary cause of mass coral bleaching is increased sea temperatures. At a local scale, many stressors including disease, sedimentation, cyanide fishing, pollutants and changes in salinity may cause corals to bleach. Mass bleaching, however, affects reefs at regional to global scales and cannot be explained solely by localised stressors operating at small scales. Rather, a ontinuously expanding body of scientific evidence indicates that such mass bleaching events are closely associated with large-scale, anomalously high sea surface temperatures. Temperature increases of only 1-2ºC can trigger mass bleaching events because corals already live close to their maximum thermal limits." (Marshall and Schuttenberg, 2006) Re: bleaching, climate change and temperature, the Australian Institute of Marine Science simply states: What is known: - Global climate is changing rapidly due to human activities and will result in continued rising temperatures both on land and in the sea. - Climate change due to the enhanced greenhouse effect has significant consequences for coral reefs. There is a direct link between unusually warm seawater temperature and bleaching of reef-building corals around the world. (http://www.aims.gov.au/pages/search/search-coral-bleaching.html) Some overviews of bleaching science containing dozens of references to the primary literature: Johnson JE and Marshall PA (editors) (2007) Climate Change and the Great Barrier Reef LINK In particular, see Chapter 10: Hoegh-Guldberg O, Anthony K, Berkelmans R, Dove S, Fabricus K, Lough J, Marshall P, van Oppen MJH, Negri A and Willis B (2007) Chapter 10 Vulnerability of reef-building corals on the Great Barrier Reef to Climate Change. In Climate Change and the Great Barrier Reef, eds. Johnson JE and Marshall PA. Great Barrier Reef Marine Park Authority and Australian Greenhouse Office, Australia Marshall and Schuttenberg (2006) "A Reef Manager's Guide to Coral Bleaching", Great Barrier Reef Marine Park Authority. LINK A few useful links: Great Barrier Reef Marine Park Authority (what is coral bleaching) LINK NOAA Coral Reef Watch (satellite based sea temperature monitoring for coral bleaching prediction) http://coralreefwatch.noaa.gov/satellite/index.html Status of Coral Reefs of the World http://www.aims.gov.au/pages/research/coral-bleaching/scr2004/

  14. An overview of glacier trends
    I have found an estimate of the North american Continental Ice sheet at the LGM,as measured in area, just in case any others might find this information usefull. " an area of about 15 million square kilometres (17.4 million, including Greenland ice)." For a full description here is the source: http://ess.nrcan.gc.ca/ercc-rrcc/proj4/theme1/deglac_e.php
  15. What do the hacked CRU emails tell us?
    Fantastic video on the hack! Posted on deSmogBlog.
    Response: Thanks for the link - have added it to the Climategate page (and what the hey, have embedded it here for ease of viewing).

  16. What do the hacked CRU emails tell us?
    Actually Chris, my original source was the BBC news - it has also been reported in the paper press as a resignation, but I accept that UEA press statement says he has stood aside as Director "until the completion of the Independent Review to ensure that CRU can continue to operate normally and the Independent Review can conduct its work into the allegations"
  17. What do the hacked CRU emails tell us?
    no he hasn't Mizimi. He's stepped aside temporarily while the review takes place. That's pretty standard practice in this sort of circumstance. http://www.uea.ac.uk/mac/comm/media/press/2009/dec/homepagenews/CRUreview what strange places you go to, to source your "information"!
  18. Measuring Earth's energy imbalance
    guinganbresil, I think maybe your (admirably!) deeply detailed and technical thinking on this topic has distracted you away from the more plain and fundamental physical fact that an imperfect insulator will continue to let out a portion of energy that is accumulating.
  19. Measuring Earth's energy imbalance
    Tom, I hate to be in a position of defending an analogy, but it does get to the root of my point. The OLR spectrum covers more than just the CO2 band. The total OLR (integrated over the spectrum) is the term that will affect the radiative balance - not just the CO2 band. If CO2 is the causative factor in radiative imbalance, it will need to dominate the overall OLR behavior. If the CO2 is not dominating the behavior of the total OLR then it could/would be an aggravating factor to other causative factors. This is CRITICAL to evaluating the applicability of predictions made by climate models. The figure 1C (Harries 2001) shown in "How do we know CO2 is causing warming?" is only showing the effect of trace gases. It gives the false impression that total OLR is going down. If you look at Harries figure 1B, it shows an increase in the range 750-1000 cm^-1 that clearly exceeds the decrease in the CO2 band. That is the "Non-CO2 hole" in the bucket. Harries explains the increase in this range as due to the effects of ice crystals not completely removed from the data set due to the differences in FOV between the IRIS and IMG detectors. This does not explain how the same effect is seen by Griggs 2004 and Chen 2007 with the addition of AIRS and TES data with different FOV's. Chen asserts that the behavior in the window region is not due to cloud contamination. Satellite measurements of total OLR also indicate an upward trend. To boil it down - looking at only the decrease in the CO2 15 um band and concluding that the overall energy balance of the Earth is controlled by that decrease neglects the effect of the non-CO2 regions of the OLR spectrum. The argument that the decrease in CO2 warms the Earth which causes the other regions of the spectrum to increase even more does not conserve energy. To go back to the dreaded analogies it is like saying that you wrap a space heater in insulation and the heater inside heats up (I agree) and the room outside of the insulation also heats up (I disagree.) I would agree with CO2 being the causative factor if the increase in the window region was less than the decrease in the CO2 band - that would make sense both with increased blackbody from a warmer Earth and still conserve energy. If more IR is being trapped by GHG's then the total OLR must decrease - this should be basic stuff - I am missing something? Look at Venus, OLR is ~150 W/m^2 compared to Earth's ~235 W/m^2... Riccardo mentioned an observed increase in OLR due to the recovery from a past transient and referenced Murphy (seen in response to #1 above). I am not aware of any historical records (Vostok etc.) indicating that we should be recovering from a large transient. The step response in Murphy shows an increase in OLR but ONLY AFTER the increase in CO2 stops. The OLR should be decreasing while CO2 increases if the CO2 is the causative factor.
  20. Can you make a hockey stick without tree rings?
    @leto, 42 My very personal opinion: Gather trustwothy anectdotal data, and proceed from there in whatever manner you have statistical justification for. If there were one proxy series of the type you are asking for, we would have known by now, I think. I can give you a couple of examples from Norway. In Halvdan Svartes saga, it is told that he drowned (about 880 CE) in Røykensvik in late winter when the ice broke under horse and sledge because of cattle being watered out on the ice and their droppings making the ice rotten. That means it can not have been much warmer than now, but not much colder either. In Eigils saga (ca 950 CE), Eigil Skallagrimson is ordered by king Håkon to take a trip to Vermland (now Sweden) to collect taxes. It seems to be about this time of year, and the saga tells us that the winter roads are cleared ('breyttir vegar'). Well, I can tell you, they are not frozen, so there is no way you can use those tracks right now, I happen to live along them. That piece of information indicates temperatures around or slightly below the 2000-2009 mean. This is all in line with the present consensus in Norway, that medieval temperatures were 0.5-1 oC higher than the 1961-1990 mean, which means about what we experience now. No amount of proxy reconstructions is going to change the historical record, and I guess quite a lot of good information is still to be gathered from careful analysis of anecdotal evidence. And the 'precision' you get from proxy reconstructions is most often illusionary. Just compare the different reconstructions.
  21. Can you make a hockey stick without tree rings?
    DeNihilist, Thanks for the response. I will look at the material in more detail, but I have already heard a lot from the anti-AGW (skeptical) camp. I am familar with the whole Yamal saga, which is part of the reason I do not trust tree rings. I am somewhat surprised I have not had any reply from the pro-AGW camp pointing me to one unambiguous non-tree proxy that fits the 'global hockey stick with local European MWP' pattern. This is, after all, supposed to be the scientific consensus, or so I'd been told. Is there such a proxy? I would have thought, from the title of this thread, that such proxies did exist. Reconstructions based on combined data don't carry the same evidential weight for me, I'm afraid. I'm not saying data can't be combined but there is always room for human subjectivity and confirmation bias to creep into the combination process. I repeat, I am not not trolling to make a point here. I would just like to know if there is any firm ground to stand on before launching into my own analysis of the more complex statistical methods. Leto.
  22. An overview of glacier trends
    An excellent read, Thanks for the suggestion.However, not much information of the sort i am seeking.
  23. An overview of glacier trends
    well, perhaps, I have other use for this data than the current climate change issue, wich i do.Thats why i was hoping someone could help me.I am specifically looking for North American continiental deglacition rates from the point in time of its southern most advance to the present day.estimated original mass,percentage of the original mass that exist today.wether it be tables, graphs etc. Im not sure that such estimates even exist.However, you have knowledge i dont wich points that its far far greater than it was in time frames of geologic scale. perhaps you could provide those geologic time frames you work with ? I have to start somewhere
    Response: I don't know of tables or downloadable data but one paper How sensitive is the world's climate? (Hansen 1993) examines the period when the Earth fell into the last major ice age, calculating the change in Earth's albedo due to growing ice sheets. Should be worth a read - a good introduction to the concept of climate sensitivity also.
  24. An overview of glacier trends
    bigdaddy, the point is that the changes we are experiencing now are far, far faster than those in more geologic time frames. That's the point, and that's the problem.
  25. Can you make a hockey stick without tree rings?
    how about isotopes from tree rings? http://www.arctic.ucalgary.ca/main/documents/media_release_pdfs/Analysis%20of%20isotopes%20in%20tree%20rings%20can%20reveal%20past%20climate%20events.pdf
    Response: This seems to be a developing technology (or to be more precise, an existing technology that has become more affordable) so hopefully this will provide a lot more proxy information in upcoming years.
  26. Was there a Medieval Warm Period?
    Anyone know if there has ever been a search through the monastic enclaves of europe/middle east, etc. for any kind of climate/temperature data from before instrument period?
  27. Philippe Chantreau at 18:24 PM on 6 December 2009
    Can you make a hockey stick without tree rings?
    Blair, watch that program again and read some books. You are extremely confused. Levels of CO2 "hundreds" of time higher than preindustrial would be at or above 56000ppm; care to point when exactly was that happening? And look at that word again from a good source. It's Neanderthal.
  28. An overview of glacier trends
    Additionally, if any could resolve Mr.Lindzens concerns about climate modeling,as expressed in this article. http://online.wsj.com/article/SB10001424052748703939404574567423917025400.html?mod=googlenews_wsj
  29. An overview of glacier trends
    Pardon me gentlmen,Its my initial observation that your discussion is based on relatively short spans of time. Could any point me in the direction to obtain graphs of N.A.contitnental ice sheet deglaciation rates in more geologic time frames?
  30. Can you make a hockey stick without tree rings?
    As far as I can see, from my perspective, the issue is not the rise in temperature, rather, what is its cause. Now, I haven't gone through all of the postings above, but it appears that little, if anything, is said about the CO2 levels. There was a program on PBS regarding mankind and our evolution. To summarize, our precursor was nethanderals. The great ice age gradually forced the nethanderals further south as a consequence of impact of great droughts. Further, statements (not in this program) have been made to effect, the CO2 levels during this period were 100s of times greater than the CO2 level today. (One wonders what brand of SUVs the nethanderals were driving?) Yet, there was an ice age. Anyhow, the survivors ended up on eastern mid-Africa. Out of the survivors, came us, the homosapiens (shades of Darwin). Indeed, our genes have nethanderal traces. The next item that is relevant to this issue of warming is the reaction time of influences. Just because you give your car gas, it doesn't mean that in 1 second you will be going 60 mph. Likewise, how long does it take for a car going 60 mph to stop. Let alone the other issue of relaxation time. i.e., once the influence is removed, how long does it take to go back to the previous level. To continue, I think that the next few winters are going to be interesting regarding the CO2 hypothesis. So far, this winter is starting up as a cold one, even though there have been forecasts of a warmer NE. To summarize, I think that that the CO2 people still have to make their argument. Certainly, their postings and data manipulations have not given a lot of people the feeling that their science is objective.
    Response: "the issue is not the rise in temperature, rather, what is its cause. Now, I haven't gone through all of the postings above, but it appears that little, if anything, is said about the CO2 levels"

    This is because proxy records tell us what temperature has been in the past, not what's causing the temperature changes. But as you say, attribution is indeed the central issue of global warming - I would go so far as to say the hockey stick controversy serves as a distraction from the more crucial observations that rising CO2 levels are causing an enhanced greenhouse effect which is the main contributor to global warming.

    The issue of relaxation time is also an important point that is rarely discussed. In an earlier post, we examined the whole concept of climate time lag and "warming in the pipeline".

    There is also a detailed examination of the argument that CO2 has been higher in the past.
  31. Al Gore got it wrong
    why are errors by al gore acceptable just because he isnt a scientist? he is reading a script isnt he? hopefully, scientists wrote the 'script'. but, if 'scientists' did write the script, then why is it filled with so many glaring lies. sorry, i cant call them errors or untruths. the included 'information' was clearly deliberate for causing alarm. so, then, back to my original question. why are errors acceptable in the global warming but so aggressively belittled and attacked when skeptics raise a legitimate question? i am very curious about the bias attitude of error forgiving/overlooking nature of global warming vs strike down global warming skeptics. heck, i would rather be a ufo believer. at least i will just get laughed at instead of being vehemently attacked!
  32. Can you make a hockey stick without tree rings?
    DeNihilist, here is a short page with links regarding Loehle. There is a lot of material here on Skeptical Science, too, if my fuzzy memory serves.
  33. Can you make a hockey stick without tree rings?
    Well, i found some time today to look over those papers, now realize that i am not a scientist but do have a capacity to understand technicalities. Chris, the Moberg paper in my opinion is top drawer, the only critique I have, is I wish that they would not lay the instrumental on top of the original data. My eyes are not as good as they use to be. Tom, the second paper you put up was to me what science should be, a constructive argument about anothers' work. thank-you. Since you don't seem to have much respect for "my friend" JoNova, how this paper then, by Loehle... http://www.ncasi.org/publications/Detail.aspx?id=3025 any hidden agendas here that I should know about? Thanx
  34. Models are unreliable
    The above article attempts to debunk the "skeptic argument." However, the attempted debunking rests upon the abnormal semantics which the article attaches to the word "prediction." As normally defined, a "prediction" is a logical proposition about the outcome of a specified statistical event that is made at a specified interval in time in advance of the occurrence of the event's outcome. As it is an example of a proposition, a prediction is true or false. I understand that the climatologist James Hansen once predicted that the highway outside his office in Manhattan would be underwater 20 years later. Hansen had made a prediction. In the event, Hansen's prediction proved false, invalidating Hansen's hypothesis. All of the article's examples of "predictions" are computed temperatures. They provide the basis for comparison of computed to measured temperatures. However, by itself such a comparison neither validates nor invalidates the associated model for the events are unspecified. With the events unspecified, the model lacks the property of "falsifiability" that is possessed by every model that is "scientific" in nature. To render one of the IPCC's models falsifiable, the builders of this method would have to specify the statistical event that is associated with each prediction. According to authorities that include the IPCC itself, this task has not yet been accomplished. In its most recent report, the IPCC states that its models do not make "predictions" but rather that they make "projections." While predictions support the validation of a model, the IPCC's "projections" support only "evaluation." The distinction is an important one, for to control any sort of system, one must have the capacity for predicting the outcomes from movement of the control system's actuators. Whether the IPCC's models have the capacity for doing so remains unknown pending the definition of the events and conduct of a validation exercise. Thus, whether regulation of carbon dioxide emissions would have the desired effect of controlling global temperatures is also unknown. Associated with confusion over the differing meanings of "prediction" and "projection" in the language of climatology is a mistake repeatedly made by people who are interested in climatology but unfamiliar with the methodology of science. This mistake is to confuse a model built by scientists with a scientific model. A scientific model makes predictions. A model that makes no predictions is not a scientific model even when built by scientists.
  35. Can you make a hockey stick without tree rings?
    i find that most of the cynic blogs are a complete waste of my time , the inhabitants therein seek only to spread denial they are not interested in fact, the best way to help is to answer their letters to the editor garbage in your local paper.remember though to make your reply interesting and use lay terms . the use of logic rather than ad infinitum scientific opinion also can be very usefull. simple and to the point ,,,
  36. Measuring Earth's energy imbalance
    guinganbresil, the bucket analogy is only that--an analogy. It's not nearly a perfect one. I'm not going to try to improve it, because that will yield diminishing returns. But consider what I wrote in #24. The real atmosphere behaves on a continuum, but with a delay. Insulation causes energy accumulation which increases temperature which increases outgoing radiation. That takes a little while, but not very long. Blackbody radiation laws that fit really well to nearly all condensed matter. Of course, a portion of that outgoing radiation gets absorbed and re-emitted, which raises the temperature, and so on.
  37. Measuring Earth's energy imbalance
    Riccardo, Look at #23-#29 (Tom and canbanjo)... I didn't see them before. I like the analogy, but the bucket should have two holes - one representing the CO2 band at 15um and the other the other represents the much larger non-CO2 OLR. As the CO2 "hole" is made smaller, the rate of water exiting the bucket is reduced (i.e. OLR goes down) and the water level starts going up. The increased pressure causes more water to exit the non-CO2 "hole". There is less water exiting the CO2 "hole" (has to be, since when the CO2 "hole" is completely closed, no water will be exiting! You don't get more water exiting a smaller hole.) The total water exiting the two holes will only start going up again when you STOP shrinking the CO2 "hole" - then it will go up until it equals the input and you are back in equilibrium. Moral of the story: OLR should be going down with increasing greenhouse effect.
  38. How do we know CO2 is causing warming?
    Riccardo, I think the confusion is in the definition of the system - if you consider the boundary at TOA, the OLR must go down to cause the radiative imbalance as described by the greenhouse effect. To say that the CO2 absorbs long wave from the surface and re-emits it back down causing a temperature increase and subsequent temperature rise that causes total OLR to increase does not conserve energy. Look at a block of CO2 at TOA - that reasoning would have it emitting more IR downward AND more IR upward! Unless it is creating energy (which it is not) or converting short wave (which it is not) or is being warmed by some other source (of which I am unaware...) this scenerio is non-physical. I fully agree with your point on increasing OLR due to a drastic imbalance in the past that we are still moving back toward equilibrium. As I understand historical CO2 concentrations, they have been much lower than present for 100K's of years, so this rapid CO2 event you mentioned did not happen in the recent past. Please take a much closer look at the behavior of a system with the step function response (as described by Murphy) driven by a ramp instead of a step. You can get a feel for it by looking at a series of small steps (like a staircase) and add up the step responses. The OLR should go down while the CO2 is going up. The OLR will go up only after the CO2 increase has stopped (or the rate has gone down significantly.) All of the complications and nonlinearities you mentioned should be buried in the step response and as long as you are in a quasi-equilibrium condition, the general behavior should hold. This is pretty basic stuff in electrical engineering (charging capacitors etc.) Concerning Venus - I found a great paper describing the atmosphere - very interesting! I thought it resembled a baked potato wrapped in aluminum foil. In fact, Venus looks cooler at TOA than Earth! This is completely consistant with the decrease in OLR with increasing CO2 I mentioned earlier. Also, a large portion of the high surface temperatures on Venus are due to the high atmospheric pressure via adiabatic lapse rate. http://yly-mac.gps.caltech.edu/Z444/Flash4/Venus_greenhouse/RT_in_Venus_Atmosphere_AGU_GM01301CH08.pdf
  39. What do the hacked CRU emails tell us?
    Also, I'd like to add that when proposing a theory, the onus is on those that aim to prove the theory correct, not on the skeptics. The skeptics provide very useful information in keeping all the scientific avenues open for exploration, and gradually theories that contradict the hypothesis may be brought down with carefully investigated evidence and with the utmost consideration... absence of politics.
  40. Can you make a hockey stick without tree rings?
    Just for the record, there are plenty of ways ocean heat redistribution can potentially impact how much heat is kept and/or brought into the system. For instance, changes in the SOI can cause changes in precipitation, increases in precipitation cause cooling and increased precipitation means (see Wentz et al. 2007 How Much More Rain will GLobal Warming for a discussion of the precipitation, temperature and WV effects of El Ninos. Cheers, :)
  41. Can you make a hockey stick without tree rings?
    #31 sgking sgking: As you seem to accept Jo Nova as an authority on this, maybe you would care to get an explanation from her why she uses the 1997 Huang/Pollack paper in the post, with no mention of their later work? If she has found errors in those later papers, it would be very interesting to know. I would also like to know your own reflection on this. Since you are referring to that blog post here, you must have made some assessments.
  42. Can you make a hockey stick without tree rings?
    Thanks, chris!
  43. Can you make a hockey stick without tree rings?
    sgking, unfortunately the person who created the stuff you linked to is misrepresenting the science. Their misrepresention of the Moberg’s paleotemperature reconstruction is described above (see my post: chris 07:25 AM on 5 December, 2009) Their misrepresentation of the 1997 Huang/Pollock/Shen (HSP1997) borehole data is a truly dismal piece of cherrypicking; the misrepresenter has declined to point out that Huang/Pollock/Shen (HPS) have already pointed out that their 1997 data is completely unsuitable for comparing the temperatures of the MWP with current temperatures[**]. They have recently concluded that their borehole reconstruction indicates that the MWP was around 0.5 K cooler than current temperatures.[*] So the borehole data is entirely consistent with all the other scientific data and analysis. [*]S. P. Huang and H. N. Pollack P.-Y. Shen (2008) A late Quaternary climate reconstruction based on borehole heat flux data, borehole temperature data, and the instrumental record Geophys. Res. Lett. 35, L13703, doi:10.1029/2008GL034187 Abstract: We present a suite of new 20,000 year reconstructions that integrate three types of geothermal information: a global database of terrestrial heat flux measurements, another database of temperature versus depth observations, and the 20th century instrumental record of temperature, all referenced to the 1961–1990 mean of the instrumental record. These reconstructions show the warming from the last glacial maximum, the occurrence of a mid-Holocene warm episode, a Medieval Warm Period (MWP), a Little Ice Age (LIA), and the rapid warming of the 20th century. The reconstructions show the temperatures of the mid-Holocene warm episode some 1–2 K above the reference level, the maximum of the MWP at or slightly below the reference level, the minimum of the LIA about 1 K below the reference level, and end-of-20th century temperatures about 0.5 K above the reference level. ------------------------------------------------- [**]HSP describe carefully in their 2008 paper why their 1997 paper (HSP 1997; used by the misrepresenter that you linked to) can’t be used to compare MWP with current temperatures. The data in HSP 1997 contains no data for the 20th century, because of concern in the large number of boreholes analyzed that the top 100 metres of depth might be contaminated by non-climatic influences. The end of the record in HSP1997 defines the estimated temperature around the turn of the end 19th century. The data in John Cook’s Figure 1 (Huang 2000) is from a set of boreholes that have passed a quality control for eliminating non-climatic contributions, and this approaches is extend much further in HSP2008 cited just above.
  44. What do the hacked CRU emails tell us?
    So Jones has resigned. UEA is conducting an enquiry into data 'misuse' The head of the world climate forum is also launching an enquiry. For an overview of the situation go here.... http://mensnewsdaily.com/sexandmetro/2009/12/01/top-global-warming-scientist-resigns-over-allegations-he-overstated-the-case-for-man-made-climate-change/
  45. Can you make a hockey stick without tree rings?
    Here are some graphs that seem to suggest something different than those above: http://wattsupwiththat.com/2009/12/04/jo-nova-finds-the-medieval-warm-period/
  46. Can you make a hockey stick without tree rings?
    John 27 response does last glacial maximum = LIA ?? If you set out to find the LIA in the borehole, stalagmite and glacial data presented above you really couldn't find it. If that data can't identify this 'period of dramatic climate change' why should we trust it to identify any period of dramatic climate change. I don't see how we can defend this data as a climate proxy and believe in the LIA. We have to throw away one or the other.
  47. Was there a Medieval Warm Period?
    I am even more perplexed now. Fig 3 and Fig 4 span 10 years of data. Fig 1 and Fig 2 span 300 years of data How can you compare 300 years of data to 10 years of data (what's more the hottest). I hope you realise that some of your detractors are accusing your side of cherry picking the data. Please don't do it on the site intended for the general public.
  48. Was there a Medieval Warm Period?
    I am a bit perplexed when i look at Fig1 and Fig2 for MWP and LIA. Why do we have this remarkable anomaly over GreenLand?
  49. Can you make a hockey stick without tree rings?
    WeatherRusty - the simplest method of getting the word out is just to post, post, post - on your blog, on Facebook, and especially on the comments sections of news sites which run the misleading stories. Link them here so they can read the info for themselves. Sure, you run the risk of more uninformed commentary, but maybe some minds will be changed.
  50. The growing divide between climate scientists and public opinion
    The challenge for objective people is to remain skeptical while not becoming drawn into the blind faith that is becoming increasingly a feature of the deniers (people who claim to be skeptics). It is important to question things but, not in the process of doing so, to deny evidence or indicators that do not reinforce a particular theory. Sadly, a significant number of people are latching on to points of view that are more driven by inverse intellectual snobbery than a considered point of view that is soundly based. My biggest concern is that points of view that reinforce our deep seated human desire to do nothing are quite appealing.

Prev  2514  2515  2516  2517  2518  2519  2520  2521  2522  2523  2524  2525  2526  2527  2528  2529  Next


The Consensus Project Website

THE ESCALATOR

(free to republish)


© Copyright 2024 John Cook
Home | Translations | About Us | Privacy | Contact Us