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Comments 75051 to 75100:

  1. apiratelooksat50 at 23:10 PM on 15 September 2011
    Climate Communication: Making Science Heard and Understood
    Oh, and the survy is not for the students. It is a survey designed by the students.
  2. Dikran Marsupial at 23:06 PM on 15 September 2011
    Climate Communication: Making Science Heard and Understood
    apiratelooksat50 perhaps it would help if you were to specify the purpose of the survey. Usually the problem with survey design is that the purpose is unclear (or that the purpose is all too clear, but disingenuous). If you want a good survey design, you first need to be clear about the intent of the study.
  3. apiratelooksat50 at 22:55 PM on 15 September 2011
    Climate Communication: Making Science Heard and Understood
    Sweet, Dunk, KR, Honeycutt I am not asking for criticisms of last years survey. That was thoroughly done already. I am asking for your contributions to this years survey. It's easy to criticize. Harder to do!
  4. Arctic sea ice low – what does it really mean?
    Interesting side note - according to the PIOMAS model results, every single day since December 20, 2009 has set a new record low volume for that day of the year. Of course, we are still waiting on Cryosat to see how close PIOMAS is to more directly measured results. It matched up pretty well with ICESat, but that has been offline for a few years now. In any case, ice volume appears to have dropped quite a bit again this year. If that continued we'd hit zero volume during Summer some time before this decade is over. The longer estimates for a 'nearly ice free' Arctic ocean in Summer all require that volume losses level off some time in the next few years.
  5. IPCC were wrong about Himalayan glaciers
    Yeah, I always love the 'no it is soot' argument.... even if it were true, the solution would be exactly the same: transition away from the coal power plants which are the primary source of increasing atmospheric CO2 AND soot. Somehow 'skeptics' never seem to make that connection.
  6. Arctic sea ice low – what does it really mean?
    #10 Not sure what you mean by 'premature post' there Jonathon, as this year goes to show we're on a trajectory, nothing premature about that assessment. As to the minimum being early (assuming that the minimum has happened), it the earliest since... 2008. Someone else may have the refreeze dates going back a few decades, but IIRC on average the dates have crept later and later, but with a great deal of variability. This year happens to be a quite early end, though still 2nd lowest or lowest extent on the record. Funny, talking about a trend with variability. I wonder where else we hear about that?
  7. Arctic sea ice low – what does it really mean?
    If we achieve an ice free Arctic ocean in the middle of the summer one year soon, the ocean becomes a giant solar collector throwing up masses of moist air with it's entrained latent heat. If this couples, like a mini Hadley cell, with the katabatic winds flowing down the slopes of Greenland, we suddenly get a huge import of heat to the ice. Ice melt could jump an order of magnitude. That would have some interesting effects. http://mtkass.blogspot.com/2008/07/arctic-melting-no-problem.html
  8. Arctic sea ice low – what does it really mean?
    Any significance to the minimum being earlier this year? The last several years showed the annual minimum occurring in mid to late September, while this year's minimum has apparently occurred in early September. Thoughts? Of course, this would be a premature post if sea ice declined further in the next year or two.
  9. Arctic sea ice low – what does it really mean?
    Look for another significant drop by 2016- perhaps 25-30% less then 2007, 2011. See 80-85% less ice compared to the 1979-2000 median in 10 years (2020 or 2021)
  10. 2010 - 2011: Earth's most extreme weather since 1816?
    Albatross - "So much for the models being too aggressive ..." Quite the contrary, the models are far too stable. They are unlikely to accurately portray the reality of a rapidly changing climate. See: Built for stability - Valdes (2011)
  11. Arctic sea ice low – what does it really mean?
    Glenn Tamblyn -" I believe, although I don't have this data to hand, that the major warming in the Arctic is a rise in winter minimums." Yup, visible in the graphs at the Danish Meteorological Institute. They don't have an animation set up (sadly) - you have to scroll through the individual years to see the trend.
  12. Arctic sea ice low – what does it really mean?
    Addendum Have a look at the post at Climate Progress http://thinkprogress.org/romm/2011/09/11/316326/new-arctic-abnormal-record-low-sea-ice-volume-area-and-extent/ Nice changing graphic of Arctic ice Extent / Area(similar) / Volume. Look at the difference in the slopes of the area vs volume graphs. Volume is sliding faster than area. Ergo. More and more thin weak ice. Not good. Not good at all!
  13. Arctic sea ice low – what does it really mean?
    Just some thoughts. I believe, although I don't have this data to hand, that the major warming in the Arctic is a rise in winter minimums. Ice tends to impose a local temperature effect on the air immediately above it that restricts maximum temps until the ice is gone. As the minimums rise, this slows ice growth through the winter since the source of the cooling leading to ice formation is air temps, not water. This can come from both more ice freezing on the top although this is limited since the freezing air is so cold. But also from the thermal gradient through the ice sheet. If the air above is cold enough, the underside of the ice can be cold enough to cause more freezing. Raise the winter minimums and the bottom freezing rate reduces and ice thickness doesn't grow as much through winter. Then the melt starts and progressively a constant melt defeats a reduced freezing rate. Obviously an additional factor is the impact that declining extent has on water temps during summer as there is more ocean to absorb heat. So this could increase summer melt rates. But I can't see how this warming would carry through that much into water temps in winter since autumn freezing would tend to suck up this heat. Then the other impact is mechanical. Ice doesn't just melt. It fractures, splits, compresses, refreezes, drifts, swells, crashes around across the Arctic basin etc. And all of these things can impact, positively or negatively on total ice volume or extent. Ice that can break up more easily, even when it is thick, can more easily float away to warmer climes where it can melt faster. Ice thickness will fluctuate through the season, even at the north pole. If thickness drops below a critical threshold is can either melt completely in Summer, or become mechanically weak because it is too thin. So in the opinion of this arm-chair expert on arctic ice, what we are seeing is rising winter air temps, more summer water heating and mechanical weakening. And the Arctic Death Spiral. Possibly the key measure of what is happening isn't extent or mass. It is the ratio. If mass is low but extent is high we have masses of thin ice - easily melted in Summer, mechanically weak. If extent is low but mass is high, what is left is thick and strong
  14. Arctic sea ice low – what does it really mean?
    Decline in the extent of winter ice since 2003 tends to confirm that warming Arctic Ocean water is eroding ice from beneath throughout the year and, at least in winter is warmer than the atmosphere. This infers that sea ice contraction is accompanied by sea-atmosphere heat exchange enhancing land based ice melt. On the other hand, can it be argued that resulting increase in glacier outflow should cool ocean water, thereby reducing the rate of sea ice erosion – which is not what we see. Is this because increased glacier output only has cooling effect in a very limited area?
  15. Arctic sea ice low – what does it really mean?
    as the Oceanic Heat Content steadily rises with the atmospheric GHG effect the effect on arctic sea ice would be steady thinning through the year, the effect of this thinning to summer ice coverage is steady rise in the acceleration of the yearly minimum if there's no changes in the oceanic currents, thus the yearly maximum would be steadily decreasing and the minimum exponentially (^1.5 faster), this line of reasoning doesn't take the slowing effect of the greenland melt in the extent of the ice into account nor the changing weather systems, f.e. when was the last time there was a stable polar vortex in the summer over arctic? computers' still acting funny so i do not wonder if this rant gets deleted on the way.
  16. 2010 - 2011: Earth's most extreme weather since 1816?
    albatross, muoncounter. Yes. I had to read the Climate Abyss piece twice. And then I knew I didn't have the scientific or stats capacity to respond - even though I saw signs of weird inconsistencies. I rather think he was attempting something just not possible in teasing out distinctions between the heat caused this and the drought caused that and AGW egging everyone on in the background (or with a conductor's baton) with no good mechanisms for discounting or augmenting inter-relationships. His explanations for choosing his methods just looked .... inadequate? If anyone's going to do this successfully, it'll take a lot more work. Maybe a tour de force from Tamino.
  17. Arctic sea ice low – what does it really mean?
    I think that the University of Bremen reported a record low based off of a single extent for one day - the NSIDC uses a five-day moving average, so it is possible that the record day may not show up in their data set. In any case it does not matter much, the past record in 2007 is a rather arbitrary line to cross. Whether 2011 breaks it or not does not change the fact that the negative trend continues. What is worth noting, however, is that the year's very-close-to-record minimum is without, if I'm not mistaken, the wind anomalies that contributed to the 2007 record.
    Response:

    [DB] The UB product uses a 6.25km resolution gridding, NSIDC 25km, adding to the difficulties in directly comparing them.

  18. IPCC were wrong about Himalayan glaciers
    You might also like to look at its soot if you are interested in the science rather than repeating skeptic talking points.
  19. IPCC were wrong about Himalayan glaciers
    Of course, black carbon and CO2 are often from same source. You might also note that black carbon has much lesser role on other ice melts (distance from asia). Also note that effect of black carbon is short-lived while CO2 is very much longer.
  20. 2010 - 2011: Earth's most extreme weather since 1816?
    Muoncounter @406, Over at M-T's place, N-G actually seems to be coming around a bit. He says: "So, this event (i.e., this particular combination of drought and heat) has been made three times as likely by anthropogenic greenhouse gases, with lots of assumptions built in." That, alas, is not how his original blog post came across when I read it at the time. M-T: "We will be seeing more and more unlikely events, I fear. At present I see things as going quite a bot worse than predicted. In which case the GCMs are not going to be especially helpful." So much for the models being too aggressive ...we are likely in for some nasty surprises down the road.
  21. IPCC were wrong about Himalayan glaciers
    5, Roh234, Wrong. From the article you linked (emphasis mine):
    "Tibet's glaciers are retreating at an alarming rate," said James Hansen, coauthor of the study and director of NASA’s Goddard Institute for Space Studies (GISS) in New York City. "Black soot is probably responsible for as much as half of the glacial melt, and greenhouse gases are responsible for the rest."
    That says black soot gets up to but not more than half. This does not equal "the major role" and may in fact be at best equal to (but probably secondary to) greenhouse gases. The concluding line?
    "Reduced black soot emissions, in addition to reduced greenhouse gases, may be required to avoid demise of Himalayan glaciers and retain the benefits of glaciers for seasonal fresh water supplies," Hansen said.
    Which means the problem is even worse, because we now have two problems to fix instead of only one.
  22. IPCC were wrong about Himalayan glaciers
    Its black carbon deposited by pollution that plays the major role in the melting. The article does imply that the greenhouse effect does play a role but the majority of the melting is caused by black carbon deposits. http://www.nasa.gov/topics/earth/features/carbon-pole.html
    Response:

    [DB] Apart from Sphaerica's fine response, you may wish to read up a bit on Himalayan Glaciers.  Your NASA reference dates from 2009.  Glaciologist Mauri Pelto has a list of blog posts on glaciers worldwide here.  The Himalayan posts are all 2009-2011.  Mauri indicates that fresh snowfall on the glaciers tends to blunt the impacts of black soot on the glaciers (due to their altitude, they retain much of the fresh snow year-round in their accumulation zones).

    Despite this, many such as the Gangotri Glacier have receded heavily over the past century:

    Gangotri

  23. 2010 - 2011: Earth's most extreme weather since 1816?
    adelady#405: "John Nielsen-Gammon's list " He's being very lukewarm lately: Precipitation: The balance of evidence does not support the assertion that the rainfall deficit since October 2010 was made larger or more likely by global warming. Temperature: Compared to long-term averages of summer temperature, the rainfall deficit accounted for about 4 F of excess heat and global warming accounted for about 1 F of excess heat. Warmer temperatures lead to greater water demand, faster evaporation, and greater drying-out of potential fuels for fire. Thus, the impacts of the drought were enhanced by global warming, much of which has been caused by man. No doubt the denierblogs are lapping this up. When Trenberth makes an attribution statement, they explode in a frenzy of 'you can't say that.' But by the law of double standards, it's ok when they do it. In what is shaping up to be a classic UT vs. TAMU battle, Michael Tobis is taking this lukewarmism on. ... what we have is not because of a change in the mean but because of a spreading, an expansion of the cloud of possibilities. From a dynamics perspective, that's not surprising in the least. We're passing, year by year, from one climate configuration to another at a very rapid pace, and we are used to thousands of years of unusual stability. ... There's a first time for everything. If you push something hard enough it will fall over. I for one think the fan is no longer pristine. ... I think it's time to take this bull by the horns. You can't apply small-signal arguments to large signals in nonlinear systems.
  24. Arctic sea ice low – what does it really mean?
    Also, it will be interesting when the Cryosat2 data goes live as a confirmation.
  25. Arctic sea ice low – what does it really mean?
    Nice post. Here is another interesting (and scary) graph from PIOMass. Ice Volume rather than Ice Volume Anomally. The bottom of the graph is 0. No Volume! My tip for an ice free Arctic - 2016 Nuff Said...
  26. 2010 - 2011: Earth's most extreme weather since 1816?
    That reminds me of John Nielsen-Gammon's list last month. "Texas Drought: Percentages At the current rate of precipitation across Texas, our rainfall percentages are shaping up to be the following (based on period of record 1895-2011): June-August 2011: 73% May-August 2011: 73% April-August 2011: 66% March-August 2011: 66% February-August 2011: 62% January-August 2011: 69% December-August 2010-2011: 72% November-August 2010-2011: 77% October-August 2010-2011: 75% Rather low precipitation departures from normal, aren’t they? Except these aren’t departures from normal. They’re departures from the previous extremes." (My emphasis)
  27. 2010 - 2011: Earth's most extreme weather since 1816?
    Here's a fun map: source Twelve months of less than 60% of the 50 year average; yeah, I'd say that's extreme. Using the metaphor of rolling a pair of dice, we expect 2-12. Nature now seems to be rolling 13s.
  28. Climate Communication: Making Science Heard and Understood
    apirate... Yeah, I think some of your questions are leading. And question #4 (I think) said "according to this graph is global temp rising, stable or falling." Well, that's not a good chart (Vostok) to determine any trend in current temps.
  29. Philippe Chantreau at 09:33 AM on 15 September 2011
    Republican Presidential Candidates vs. Climate Science
    That NYT editorial makes a number of good points indeed. You have to admire the depth of denial of a guy like Perry. Texas is ablaze with wildfires, in the grip of a megadrought, seeing 100 degrees plus temperatures for more days in a row than ever in more locations than ever but it's all scientists trying to get more money. Not a shadow of doubt in his mind. I guess that's what you get with faith driven elected officials. I remember back in the days I lived in North-Central Texas, having 30 consecutive days of 100+ temp was considered unusual. That was only about 10 years ago.
  30. Climate Communication: Making Science Heard and Understood
    Why not show a graph like this? Then you might ask students to determine whether there is anything different about the temperature rise prior to the MWP and that of the last hundred years. What is the purpose of doing this survey? Are you going to have them retake the survey after they finish the unit? That would be a way to see if they've really learned something.
  31. Medieval Warm Period was warmer
    The 10 hottest years in which region? The peak warmth occurred in different times at different places.
  32. Climate Communication: Making Science Heard and Understood
    apiratelooksat50 - Just looked at your previous (last years) survey. It's horrible! You've preset your answers with limited and misleading information (as in question 2, "From the graph: the Earth's current average temperature is:", where your graph doesn't show current temperatures), 'poison the well' for the questions about renewables, load queries with words like 'disastrous', etc. It's about as unbiased as a "Clean Coal" advertisement, and clearly intended to lead the survey respondents into supporting your position. That's the kind of 'survey' I would expect from an ad agency drumming up support for a client, not from a teacher.
  33. Climate Communication: Making Science Heard and Understood
    I particularly like the second question, where you ask the respondents to determine whether temperatures are currently increasing, stable, or decreasing... "based on" a graph which does not SHOW current temperatures. That's a neat trick. How could anyone possibly think this survey was biased? Why, the gratuitous complaints about renewable energy being expensive and unreliable prior to asking whether respondents would be willing to pay higher energy costs to reduce CO2 levels alone shows how 'impartial' it is. :]
  34. Climate Communication: Making Science Heard and Understood
    Come to think of it, I'd like your answers, pirate, before the course begins and your students' answers at the completion of the course.
  35. Climate Communication: Making Science Heard and Understood
    I'd like your students' answers to the following. This would serve better as a diagnostic near the beginning of the course. 1. Do you understand how carbon dioxide in the atmosphere works to keep the planet warmer than it would be without carbon dioxide? a. yes, very well b. yes, pretty much c. err . . . sort of d. not really e. no clue 2. If you answered "yes" to question 1, choose the answer below that best describes the process of CO2 warmth. a. CO2 naturally emits heat and thus warms the atmosphere. b. Radiation from the planet's surface "bounces" around between "greenhouse" gas molecules before it eventually escapes to space. c. Greenhouse gases trap heat like a greenhouse roof. d. Since pressure causes heat, the weight of CO2 in the atmosphere causes the surface to warm. 3. Atmospheric CO2 is increasing rapidly and has been for a century. How do we know that this increase is caused by humans? a. Humans cannot cause changes in the climate. b. We don't really know, but we have been releasing massive amounts of CO2 through the burning of fossil fuels and use of concrete. c. Studies show that features of the natural world, like the oceans, have stopped acting mainly as sources for CO2 and instead have been acting as sinks; at the same time, we are releasing massive amounts of CO2. We also have isotope studies. d. We don't know because the measurements of CO2 are all flawed and do not match each other. 4. How much credence do you give to the idea that working climate scientists would intentionally misrepresent climate science in order to make more money for themselves? a. It's ridiculous. Climate scientists make good wages, and any funding they get they have to use on projects. A few make money on books, but the books did not have a market until the so-called 'skeptics' began to resist the message of the science. b. I can see how it might happen. After all, companies that make war machines profit from war, and they usually strongly support going to war. c. I doubt it; government-funded scientists don't have to work from the profit motive. d. Of course: it's all a giant hoax to rip off taxpayers. 5. Natural climate cycles occur. The sun's radiated energy waxes and wanes. Earth's orbit wobbles and ovals. The continents move. La Nina and El Nino happen. How do we know that these natural cycles aren't responsible for 20th/21st century warming? a. I don't know. b. The cycles with all of those listed are either too long, too short, or too weak to match current warming, though there may be other cycles we don't know about, and that fact invalidates climate models. c. The cycles with all of those listed are either too long, too short, or too weak to match current warming. d. We do know that it is natural cycles. The sun is causing the current warming trend. 6. What do the IPCC and other international agencies predict about global warming if we do nothing to stop it? Check all that apply. a. The Mississippi River will be dry in 100 years. b. There will be no summer ice in the Arctic by 2100. c. Plants and animals will be forced to adapt to changing conditions, and some species will become extinct. d. The Earth will be on average 10C warmer in 2100. e. The Earth will be on average 2-5C warmer in 2100. f. The seas will rise up and drown coastal cities. g. Many glaciers will melt, causing a loss of drinking water for tens of millions of people. h. The changes will cause big migrations of people. i. Over the next century, some areas will get more intense rainfall, and other areas will become very dry. j. People around the equator will burn to death. k. food and water prices will continue to rise rapidly. 7. What is more important, a healthy economy or a healthy environment? Note that choosing one does not mean you think the other is not important. 8. If you believe that a rapidly warming planet is a problem, how will (not "how can") that problem be solved? a. through individual action alone, using the mechanism of the free market. b. through government-subsidized clean energy start-ups. c. through direct government intervention. d. through government regulation programs like carbon trading. e. through cultural change, a movement to live differently. f. it won't be solved. We'll just have to pick up the pieces after the worst of it and then build the world in a better way. 9. Do you think climate science should be publicly funded (as it is now)? a. yes b. yes, and funding should be increased c. no d. no - climate science should be subject to the forces of the market, like any other product 10. How different will the world be for your grandchildren due to global warming? a. no different. b. different, but better, because we will have solved the problem. c. different -- worse, because people will be fighting for resources instead of working together. d. different, but only a little different because the problem isn't really that bad. e. different, but better because more territory and resources will be available in a warmer world. Willing to share your answers, pirate?
  36. Climate Communication: Making Science Heard and Understood
    A Pirate: One of the criticisms last year was the survey chose a graph showing long term (800,000) year climate with CO2 having a lag to temperature and then asked questions about current Global Climate Change. You biased the sample by showing an unrelated graph that suggested CO2 always follows warming. Perhaps this year you could show the GISS temperature graph first (which actually relates to AGW, unlike the ice core data you showed last year) and then ask if it is getting warmer? You could compare last years answers to this years answers and see if the lead in graph influences peoples responses. You claim your students make up the survey on their own but the graph they used was the same one that you used in one of your first posts to question Global Warming. If they use data that is independant from your opinions it will seem less biased. The impression that I was left with is that you teach your students that AGW is not occuring before they make up the survey.
  37. Republican Presidential Candidates vs. Climate Science
    Every time I listen to Gov. Rick Perry of Texas and Representative Michele Bachmann of Minnesota talk about how climate change is some fraud perpetrated by scientists trying to gin up money for research, I’m always reminded of one of my favorite movie lines that Jack Nicholson delivers to his needy neighbor who knocks on his door in the film “As Good As It Gets.” “Where do they teach you to talk like this?” asks Nicholson. “Sell crazy someplace else. We’re all stocked up here.” The above is the opening paragraph of Thomas Friedman's op-ed, “Is It Weird Enough Yet?” published in the New York Times on Sep 13, 2001.
  38. Climate Communication: Making Science Heard and Understood
    I meant a link to the previous discussion where the denizens of SkS attacked you survey because the conclusions contradicted the group ideals.
  39. Climate Communication: Making Science Heard and Understood
    Mark Harrigan - Great link, thanks!
  40. apiratelooksat50 at 01:06 AM on 15 September 2011
    Climate Communication: Making Science Heard and Understood
    pbjamm at 6 Per your request is the link from last year's survey. I would like to know why you consider this request to not be objective. But, that is not a topic for this site. You can respond to the e-mail in #4. http://www.surveymonkey.com/s/5TTX57B
  41. Climate Communication: Making Science Heard and Understood
    apirate@4 "I posted a link to our survey from last year and was roundly criticized for it's design because the results contradicted some of the ideals held by visitors of this site." Have you completely given up on even pretending to be objective? Your comments of late have been almost entirely combative and you assertions baseless. As I (vaguely) recall your previous survey was not criticized because of its conclusions but because of its poorly worded questions and small sample size. Perhaps you would care to link to the original discussion to provide some evidence for your claim. That is pretty common practice in rational discussions.
  42. Climate Communication: Making Science Heard and Understood
    Great site - thanks for publicising here. Another wonderful link that I think says it all in one page can be found here NASA key climate indicators I certainly find it useful
  43. apiratelooksat50 at 23:59 PM on 14 September 2011
    Climate Communication: Making Science Heard and Understood
    My Environmental Science classes are studying Climate Change. Once again they are going to present a survey that will be sent to all students and faculty in our school and perhaps the district. I posted a link to our survey from last year and was roundly criticized for it's design because the results contradicted some of the ideals held by visitors of this site. This year if any of you would like to design the survey, I will gladly post it. It needs to be 10 questions long and neutrally worded. It will be posted on www.survymonkey.com If you are interested please contact me at mikemacdonald64@yahoo.com Thanks, Mike
  44. Medieval Warm Period was warmer
    Fitz1309, like many 'skeptic' arguments this boils down to arguing that climate science has failed to do the impossible; 'They have not compared 300 years of AGW warming to the 300 years of the MWP'... obviously AGW hasn't been going on for 300 years and thus the data to perform such a comparison does not exist. 'They have not compared the 10 hottest years of AGW (thus far) to the 10 hottest years of the MWP'... proxy data resolution is not detailed enough to identify what the 10 hottest years (globally) of the MWP were with any confidence, let alone to generate a map of global variations for such a small time period. In the realm of things which might be possible; A comparison of the last 50 years to ~1026-1075 would show less pronounced differences than the maps above, but the overall conclusion would be the same. A few small parts of the world were slightly warmer back then, but the vast majority of the globe is much warmer now.
  45. Dikran Marsupial at 23:02 PM on 14 September 2011
    Medieval Warm Period was warmer
    Fitz1309 The argument that a 300 year average is bound to appear colder than a 10 year average is bogus. A 10 year average will have greater variability than a 300 year average because there is less data, however that would be equally likely to make it colder than the "true" temperature as warmer. Picking the warmest 10 years in the MWP would indeed be cherry picking, if someone used such evidence to claim that the MWP was warmer than now that would be bogus. However it would be a good way to show that current temperatures are warmer than the MWP, if it were the case even though you cherry pick the data that minimises the evidence in favour of the hypothesis. Having said which, if you look at the magniture of the difference, I rather doubt cherry picking a ten year period in the MWP would make much of a difference anyway.
  46. Medieval Warm Period was warmer
    Fitz, see Daniel Bailey @ post 20 of this thread. You're looking for a graph, and Daniel has a few for you.
  47. There is no consensus
    Roh: "And in the Oreskes report he took a poll in 'refered journals'. There has been rejection of skeptic papers in the journal as it 'goes againt the consensus'." Roh, you really don't understand how journals work, do you? You assume there's pressure on journals to adhere to the consensus. Why? What's the mechanism? If anything, there's pressure not to adhere to the consensus. Who would want to reject a paper because it "blows a hole" in the dominant theory? That's the kind of stuff that Science and Nature salivate for. In reality, though, there's simply pressure to get the science right, whatever it might mean for our understandings. Don't you agree?
  48. Medieval Warm Period was warmer
    I've just read an argument claiming that the maps you display above comparing the MWP to the last decade anomaly isn't repersentative as you're comparing 300 years to 10 so it's bound to appear colder. Perhaps a map of the 10 years at the height of the MWP would be more repersentative, but then I guess you have the problem of which years to pick as you'll be accused of "cherry picking" which ever you do.
  49. IPCC is alarmist
    lancelot, no the Wikipedia article does not attribute Pachauri's position to the IPCC. In any case, it hardly matters whether 'you' or 'your interpretation of the Wikipedia article' are incorrect... the position stated (by whomever) is not accurate. You also still haven't given ANY reason for the claim that 350 ppm is "crying wolf"... which is certainly your own claim rather than anything in the Wikipedia article. It needs to be understood that the primary difference between Hansen's 350 ppm estimate and the more common 450 ppm estimate of 'safe' CO2 levels is the timeframes involved. If we look only at 'fast' (e.g. within 100 years or so) feedbacks then we could likely go up to about 450 ppm. However, if you take the long term view then going over 350 ppm would eventually cause significant warming and flooding of major coastal cities around the world. The relevant questions then become how soon would major consequences from exceeding 350 ppm manifest, and would that allow us enough time to get back down below 350 ppm. Is 350 ppm a reasonable target to get back down to within 500 years? I'd say yes... if we switch away from fossil fuels in the next several decades and then work on technologies to pull CO2 out of the atmosphere that seems entirely possible. Could we get back to 350 ppm within 50 years? Certainly not... but then we shouldn't be seeing major problems (e.g. large sea level rises, major agricultural disruptions, millions of deaths) in 50 years unless we continue to push CO2 levels higher.
  50. Hockey stick is broken
    Roh234, as others have pointed out, the 'hockey stick' has been confirmed by numerous subsequent studies by different groups of scientists, and even 'skeptics', all over the world using several different data sources. Alot of this is also detailed in the article above. On McIntyre's specific claim about 34 tree ring data sets... have you heard of the divergence problem? Basically, over the past century many trees have shown very low growth even as the temperature has increased. This is believed to be due to environmental toxins and other factors. However, what it means is that the rings on these trees are not accurate proxies for RECENT temperatures. Thus, McIntyre essentially went out and found recent tree rings (from a completely different study BTW) that did not match ACTUAL temperatures and is claiming that Briffa should have factored them in. In short, he is criticizing Briffa for not using INCORRECT data. That McIntyre is wrong should be obvious to any thinking person who looks at the graph. The red and black temperature lines essentially match up until the last 50 years or so. Then the black line plummets downward while the red shoots up. Now let's engage basic reasoning for a moment... What have actual temperatures done over the past 50 years? Has it gotten significantly colder? If not, then the black line is wrong. Ask yourself how 'skeptical' you are being when you blindly accept the validity of a graph which is at odds with observed reality.

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