Milankovitch Cycles

Discussion in 'Earth Science' started by space_geek, Feb 28, 2009.

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Your take on Milankovich Cycles

Poll closed Mar 15, 2009.
  1. Warming Earth

    14.3%
  2. Cooling Earth

    42.9%
  3. Insignificant

    14.3%
  4. Don't know about it

    42.9%
Multiple votes are allowed.
  1. iceaura Valued Senior Member

    Messages:
    24,432
    I found your interpretations, and the judge's, easy to understand and (once corrected from the original hyperbole, in this thread) plausible, and I said so.

    I don't think you have demonstrated that they are correct, however, and I don't think they are. By this I mean that I don't think that's what Gore was referring to in his cryptic little side comment, and the kinds of evidence you present are basically irrelevant - the judge's ruling, for example, has nothing to do with what Gore meant by what he said.

    But the entire argument is now beside the point, as far as my original question is concerned or the subject of this thread, OK? It is an example of this:
    , in that it has nothing to do with Gore's argument in the movie. It is at least two levels away from the physical issue, i.e. the "substantial" or "factual" situation that some claim Gore made many "errors" about.

    Apparently you are not among those people, and are complaining about another kind of "error" entirely, which I have no strong opinion about. I'm perfectly willing to agree that Gore's use of stock footage of ordinary glacial calving to illustrate anthropogenic meltback, or failure to include both sides of scientific debates about such things as the melting of the snows of Kilimanjaro, or failure to emphasize that many global warmings of the past were probably started by other factors than CO2 buildup, or side reference to all those islanders evacuating, are potentially misleading - have in fact misled many.

    The question of whether any such movie as Gore's could be made in such a way that it misled no one or at least very few people - how much Gore should be blamed for these flaws - is very interesting. I don't think, for example, that the film footage and movie dramatizations of the Apollo missions should be blamed for the common impression they created that there is no gravity in space or on the moon. We are just now getting a handle on how misleading even accurate documentary footage of events can be, the inherent problems with visual learning (first suggested by professional sleight of hand performers), and so forth.

    But it hardly belongs on this thread.
     
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  3. Trippy ALEA IACTA EST Staff Member

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    And yet you have not managed to present a single coherrent and reasonable interpretation of Al Gore's words.

    I'm struggling to find a coherrent statement in here, in fact it smells a lot like backpeddling.

    His statement about the citizens of those pacific islands wasn't just misleading, it was plan old wrong.

    Equally galling is the fact that in his response to the court case, Gore stated that he had evidence and such to support each of the points that had been questioned.

    There IS NO EVIDENCE of pacific island nations (note, Gore used the plural form, not the singular form) being evacuated to New Zealand as a rresult of rising sea levels.

    Gore should be responsible for his errors, end of story.
    He presented it as a factual piece, and a documentary.
    Lord Monckton identified 3 dozen scientific errors in the film, some of which (or all of which) were bought up in the case. So yes, Justice Burton ruled it as misleading, but he ruled it as misleading because of the scientific errors it contains.

    And as for it not belonging in this thread, I believe it originally came up because I was (essentially) critiscizing the implication made by Buffalo Roam that Al Gore invented global warming, or had something to do with serious global warming research.

    You claim that there are other reasonable interpretations, and yet you have failed to provide a single one of them.

    NOTE: I am neither citing Lord Monckton as an expert source, nor implying that I support his views, I am simply putting forward some of the other views on Gore's movie.
     
    Last edited: Mar 4, 2009
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  5. iceaura Valued Senior Member

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    I think you were misled. Which is OK, because I agree the statement is easy to take wrong. I think it may even be wrong - there's a chance Gore had some news story mixed up. I'll ask him, if I ever have the chance. But don't claim your take on it is the only one possible, OK? Because my initial take on it was just that some islanders had had to evacuate from some effect of rising sea levels, and at least a few had ended up in NZ. And that take is perfectly consistent with Gore's argument in the movie, and the context of the quote, and the circumstances of islander evacuations as found in the news, and so forth.
    I'm perfectly willing to answer questions if I have been unclear. I am not willing to take your misreadings as my assertions, though. Stuff like this:
    which is your third or fourth different interpretation of what Gore said, I'm not going to answer for when presented as mine.
    Well, those are all bullshit. I'm familiar with that crackpot's claims. And if you're getting your facts of the world from Glenn Beck, you're in trouble.
    No, that wasn't his reasoning. He's an intelligent man, and he can tell the difference between a polemical argument for one side of an issue and a scientific publication. He ruled that the movie contained potentially misleading segments if used as a scientific resource in the British schools , because it omitted proper qualifications and caveats for some of its presented evidence, not because it contained errors of fact.

    Furthermore the judge didn't rule that the movie as a whole was misleading at all. He ruled that overall it made its case clearly and persuasively, and presented a sound argument on an important matter. So claiming the judge ruled the movie was misleading due to errors it contained is globally false, as well as specifically.
     
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  7. Trippy ALEA IACTA EST Staff Member

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    And you have the nerve to accuse me of distraction.
    You're the one that has been claiming it is mearly misleading rather than factually accurate.
    It contains errors of fact.
    There has been no evacutaion of pacific island nations to new zealand.
    It is not reasonable to interpret proposed evacuations of the carteret islands to PNG as an event that has already happened, and involves an evacuation to NZ.
    It is not reasonable to state that this is because of global warming when the UN has sated there are, or may be other factors involved.
    It is not reasonable to state that the evacuation of a nation because of nuclear fallout is because of global warming.
    You have agreed that it is not reasonable to assume that your scenario of people leaving villages to go to the bigger cities, because of global warming would still attract media attention.

    Finally, from Justice Burtons judgement:

    Paragraph 17, point III:

    "There are errors and omissions in the film, to which I shall refer, and respects in which the film, while purporting to set out the mainstream view (and to belittle opposing views), does in fact itself depart from that mainstream, in the sense of the "consensus" expressed in the IPCC reports."

    Paragraph 19:
    "Of course that is right, and ss406 and 407 are not concerned with scientific disputes or with the approach of teachers to them. However, as will be seen, some of the errors, or departures from the mainstream, by Mr Gore in AIT in the course of his dynamic exposition, do arise in the context of alarmism and exaggeration in support of his political thesis."

    Paragraph 21:
    "However, for those same two reasons set out in paragraph 19 above , the teachers must at least be put into a position to appreciate when there are or may be material errors of fact, which they may well not, save for the most informed science teachers."

    Paragraph 22:
    "But Mr Downes sensibly limited his submissions to concentrate on those areas where, as he submitted, even on Dr Stott's case there are errors or deviations from the mainstream by Mr Gore. Mr Downes produced a long schedule of such alleged errors or exaggerations and waxed lyrical in that regard. It was obviously helpful for me to look at the film with his critique in hand."

    Paragraph 23:
    "All these 9 'errors' that I now address are not put in the context of the evidence of Professor Carter and the Claimant's case, but by reference to the IPCC report and the evidence of Dr Stott."

    Paragraphs 24 - 33 are labled "The 'Errors'".

    Paragraph 34:
    "As set out in paragraph 14 above, I am satisfied that, in order to establish and confirm that the purpose of sending the films to schools is not so as to "influence the opinions of children" (paragraph 7 above) but so as to "stimulate children into discussing climate change and global warming in school classes" (paragraph 6 above) a Guidance Note must be incorporated into the pack, and that it is not sufficient simply to have the facility to cross-refer to it on an educational website. The format of the Guidance Note put on the website is helpful, in splitting up consideration by reference to the three different categories of teachers who may make use of the film, those teaching science, geography and citizenship, and to include a chart, by reference to the various scenes of the film, which both includes descriptive passages and raises questions for potential discussion. I have no doubt that some teachers of science or geography will have a much broader knowledge of the subject than is simply contained in the film and in the existing Guidance Note, and will be in a position to assist in the stimulation of such discussion. However, as set out in paragraph 13 above, that is plainly not so for the majority of teachers. In any event it is important that, in such guidance, any serious apparent errors should be identified, not only so as to encourage informed discussion, but also so that it should not appear that the Defendant, and, as a result of the Defendant sending the film to schools, schools, are promoting partisan views by giving their imprimatur to it. That is not to say of course that there needs to be comment on every single aspect in the film in the Guidance Note nor discussion of every scientific dispute. However, it is noteworthy that in the (unamended) Guidance Note there is no or no adequate discussion at all, either by way of description or by way of raising relevant questions for discussion, in relation to any of the above 9 'errors', the first two of which are at any rate apparently based on non-existent or misunderstood evidence, and the balance of which are or may be based upon lack of knowledge or appreciation of the scientific position, and all of which are significant planks in Mr Gores's 'political' argumentation."

    Paragraph 35:
    "The introduction to the Guidance Note, as it stands, indicated that "the pack seeks to help teachers to engage pupils with … questions, discuss the facts and test the science". But the absence of comment about and correction of the 'errors' detracts from that prospect."

    Paragraph 36:
    "The lack of addressing of the 'errors' in the existing Guidance Note was exacerbated, as Mr Downes submitted, by other passages in it:
    i) In a discussion of the relationship between carbon dioxide and rising temperature, a question was raised for "possible teaching activities" namely: "Is CO2 the cause of rising temperatures or is rising CO2 caused by rising temperatures? Sceptics say we don't know – what is the explanation in AIT?" Plainly this is unsatisfactory, since it is common ground that the explanation in AIT is at best materially incomplete (see the fourth 'error' above).

    ii) In the part of the Guidance Note which relates to discussion in citizenship classes, teachers are encouraged to raise the questions:

    "Consider the reason why politicians may have wanted to ignore climate change? …
    What pressures can be put on politicians to respond to climate change?"
    iii) In the suggested planning of a whole day event on climate change for citizenship classes, there is no suggestion at all of the discussion of opposing views to that of Mr Gore, and the list of "Suggested Organisations for the Climate Change Fair and as Guest Speakers" is limited to organisations which support his views."

    Paragraph 37:

    "As a result of considerable discussion in Court, which I, and both Counsel, strained to avoid becoming a drafting session, a new Guidance Note has now been produced which the Defendant proposes to include in the pack, and which, to my satisfaction, addresses all of the above 9 'errors', both by drawing specific attention to where Mr Gore may be in error and/or in any event where he deviates from the consensus view as set out in the IPCC report, and by, where appropriate, raising specific questions for discussions. I need only refer, by way of example, to the insertion in respect of scene 21, of the following passage relating to the first 'error', with regard to sea level rise..."

    Paragraph 38:

    "It may also be interesting to note what the Defendant has inserted in relation to the second of the above 'errors', with regard to the evacuation to New Zealand:

    "Note: It is not clear what "Pacific nations" Gore is referring to in the section dealing with evacuations to New Zealand. [bIt is not clear that there is any evidence of evacuations in the Pacific due to human-induced climate change
    . Teaching staff may wish to use this as an example of the need in scientific presentation to give proper references for evidence used. However, the IPCC does predict that for small islands sea level rises will exacerbate storm surges and other coastal hazards and that, by the middle of this century, climate change will reduce water resources to the point where they become insufficient to meet demands in low-rainfall periods."..."

    Paragraph 40:

    "The amended Guidance Note contains in its introduction a new and significant passage:

    "[Schools] must bear in mind the following points
    AIT promotes partisan political views (that is to say, one sided views about political issues)
    teaching staff must be careful to ensure that they do not themselves promote those views;
    in order to make sure of that, they should take care to help pupils examine the scientific evidence critically (rather than simply accepting what is said at face value) and to point out where Gore's view may be inaccurate or departs from that of mainstream scientific opinion;
    where the film suggests that views should take particular action at the political level (e.g. to lobby their democratic representatives to vote for measures to cut carbon emissions), teaching staff must be careful to offer pupils a balanced presentation of opposing views and not to promote either the view expressed in the film or any other particular view. "

    Do you see that? 20 paragraphs in a 46 paragraph judgement where Justice Burton explicitly refers to them as errors, and a judgement where he requires them to include in the guidance that the film does, or may contain errors, not misleading statements, not misleading segments, but errors.

    I thought you said you had read this?

    For reference:

    Main Entry: error
    Part of Speech: noun
    Definition: mistake; wrong
    Synonyms: X*, absurdity, bad job, blunder, boner*, boo-boo, delinquency, delusion, deviation, erratum, failure, fall, fallacy, falsehood, falsity, fault, faux pas, flaw, glitch, goof*, howler, inaccuracy, lapse, misapprehension, misbelief, miscalculation, misconception, miscue, misdeed, misjudgment, mismanagement, miss, misstep, misunderstanding, offense, omission, oversight, screamer, screw-up, sin, slight, slip, slipup, solecism, stumble, transgression, trespass, untruth, wrongdoing
     
  8. iceaura Valued Senior Member

    Messages:
    24,432
    If you have convinced yourself that your post there is relevant, and answers the matter at hand, then I am likewise satisfied. I have already failed at avoiding further repetition once, but this looks like an even better opportunity. Over and out ?

    I can't resist: Notice that the judge puts the word "error" in British single quotes, whenever making a specific reference to the film, thus: 'error'. Notice also what the judge deemed acceptable by way of guidance to British teachers dealing with these 'errors' - not retraction, or correction, but expansion and context, explanation or qualification.

    Do you suppose the judge did that on purpose?

    Along those lines, what do you suppose the judge meant by this:
     
    Last edited: Mar 4, 2009
  9. Trippy ALEA IACTA EST Staff Member

    Messages:
    10,890
    If you want to cop out of the discussion, and avoid admitting your error (sorry, misleading statement) then by all means, feel free not to reply to this post.
     
  10. Slacker47 Paint it Black Registered Senior Member

    Messages:
    667
    Well, I am not going to jump into this ridiculous fight because there is too much to sort through. I will, however, discuss Milankovitch cycles.

    In the cycle that Earth orbits the sun further and closer, does the proximity to the sun cause any change in temperature? Of course the Earth would intercept more photons being closer than further, but does that cause a temperature change?

    Secondly, the change in tilt causes seasonally variant climate change. The plants on Earth are responsible for many weather and climate patterns at a large scale. A change in seasonal length and intensity would have a great impact on latitudes in question.

    In our current elliptical orbit, the Earth is closest to the sun around January 9th and furthest around July 4th. Does anyone have data about the amount of SW radiation change during these days?
     
  11. Buffalo Roam Registered Senior Member

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    16,931
    Actually the Earth orbit is now almost circular, but it will eventuall extend out to a eliptical orbit,

    http://www.globalchange.umich.edu/globalchange1/current/lectures/samson/climate_patterns/

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    Figure 9. Eccentricity changes on a ~100,000 year cycle.

    Copyright ©Regents of the University of Michigan

    TITLE 17 > CHAPTER 1 > § 107Prev | Next § 107. Limitations on exclusive rights: Fair use
     
  12. Slacker47 Paint it Black Registered Senior Member

    Messages:
    667
    Thank you. I hope that clears up alot of useless fighting.

    So, the present trend of orbit is 'regular.' The current tilt of the earth is 'regular' or average.

    So, why is the earth increasing in temperature? My thoughts fall on the amount of gasses added by humans... as well as the increased amount of chemicals and space for organisms to process thier daily intake and output gas. The space that I refer to is the organized system of land (and water) that humans have created that let organisms flourish in specific habitats. For example: fields for cow grazing, refuse for bacteria (i cant think of anymore right now). The amount of changes that man has made to the book of life physically and to intellectual process is only increasing quickly.

    Regardless of natural cycles, humans are creating a complex world for themselves at the expense of the rest of the world. It could be debated as necessary or greedy. I believe that the management of resources needs to be very closely examined. In a time of relative warmth, should we not save our coal and oil for a "natural" cold event. In an ice age, I would much rather my children be warm than us complaining about it now in 20 - 40 degree farenheit weather. We must consider the future.
     
  13. Buffalo Roam Registered Senior Member

    Messages:
    16,931
    I would say because of the orbit being in a period of low eccentricity, perihelion, we are recieveing more energy over the year, but from what I read, we are now moving into aphelion,

    Presently, we are in a period of low eccentricity (~3%) and this gives us a seasonal change in solar energy of ~7%. When the eccentricity is at its peak (~9%), the "seasonality" reaches ~20%. In addition a more eccentric orbit will change the length of seasons in each hemisphere by changing the length of time between the vernal and automnal equinoxes.

    Currently the difference between closest approach to the Sun (perihelion) and furthest distance (aphelion) is only 3.4% (5.1 million km). This difference is equivalent to about a 6.8% change in incoming solar radiation. Perihelion presently occurs around January 3, while aphelion is around July 4. When the orbit is at its most elliptical, the amount of solar radiation at perihelion is about 23% greater than at aphelion. This difference is roughly 4 times the value of the eccentricity.

    So when we are in the period of low eccentricity, we recieve more energy form the sun over the year, and do not cool off as much in the aphelion,

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    now once the orbit goes to a period of high eccentricity, we have a much shorter exposure to peak solar energy in the aphelion, and a much longer and colder Perihelion.

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  14. Trippy ALEA IACTA EST Staff Member

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    Also don't forget that as the eccentricity changes the velocity changes, currently in the northern hemisphere, the "Summer" half of the year is 6 weeks longer than the winter half of the year, but as the eccentriocity changes, so will that.

    One of the down sides of living in the summer hemisphere is that our winters are longer, and occur when the earth is at aphelion. The flip side of that is that our summers are shorter, and occur at perihelion.
     
  15. Slacker47 Paint it Black Registered Senior Member

    Messages:
    667
    BuffaloRoam,

    wow, 6.8% is a big difference. I was unaware of the data. I will have to do more research. Thanks
     
  16. Buffalo Roam Registered Senior Member

    Messages:
    16,931
    I am glad to help.

    I find this very interesting, and only have become aware of this because of the Thread, but it tickled my fancy and I am doing some research on the subject, and this would seem to say that the Milankovitch Cycles has far more to do with Global Warming than anything anthropomorphic.
     
  17. Buffalo Roam Registered Senior Member

    Messages:
    16,931
    ice, Trippy beat you senseless, and you weren't even in the debate, Al Gore is not and never has been correct.

    Al Gore is a fear mongering politician who has a agenda, and is using that agenda to further his own wealth.

    ALGORE has a carbon foot print the size of China, He spews 800 times the ammount of Carbon as the average person in the world.

    If it was so important to the cause of stopping global warming,

    WHY, HASN'T HE REDUCED HIS CARBON FOOT PRINT TO THE SIZE THAT HE DEMANDS WE MUST LIVE AT?

    He know nothing about the subject He expounds on and doesn't take the time to even do simple investigation of the subject let alone serious scholarly research into the Subject of Global warming.
     
  18. Slacker47 Paint it Black Registered Senior Member

    Messages:
    667
    In terms of milankovitch cycles, the earth is naturally on a cooling trend of 50 million years. However, we are in a warming short-term trend. The addition of anthropogenic greenhouse gasses will cause an even greater warmth. Changes lag behind the cause. So if we are creating warmth, the total effects will not be felt until it is too late to change.

    Milankovitch cycles happen at too long of cycles to cause the rates of warming that are occuring today. Major implications of this type of change are major changes in climate at regional and local scales. Good luck.
     
  19. Buffalo Roam Registered Senior Member

    Messages:
    16,931
    Now prove that.
     

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