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Global Warming

  1. Oct 9, 2007 #1
    I know there is already a post on this, but I just wanted to make a point.

    I live in California, so obviously there is a great deal of controversy here by the coast and especially where I am (a small conservative community) whether or not warming is legit (long story short, I believe...). Anyhoo, I was recently speaking with an exchange student from Hong Kong, and she matter of factly stated a few things about global warming. Surprised, I asked her if she had any doubts. Nope. Her textbooks teach it, back it up, and give you the facts, agree or disagree. She explained that it made perfect sense, and mainland China was beginning a campaign to save the coast and raise awareness. Now, for all the global-warming-China-destroying-the-ozone-bashing I hear, that's pretty neat. Anyone here agree? Disagree?

    Should scientific subjects be forcibly taught in schools? (Not talking about creationism.)
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  3. Oct 31, 2007 #2
    Well, it is very comforting to hear that China, a big consumer of coal and other sources of greenhouse gases, seem to be aware of the problem of global warming. As a growing economy with tremendouse growth potential, it is very imporant that the new development takes measures to ensure environmental sustainability for the generations to come.

    Whether something should be forcibly taugth in schools or not is rather difficult however, as people should be allowed to believe what they want. The great paradox of freedom of speech... However, personally I would like to see greater awareness raised about sustianable development. Now what your friend is saying sounds very promising, and hopefully other countires will also make an effort to raise awareness about environmental degradation as much of our economy and way of life depends on limited resources being used in a sustainable manner.
  4. Oct 31, 2007 #3

    jim mcnamara

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    The forcibly taught thing is more suited for discussion in another forum, like General Discussion.
  5. Oct 31, 2007 #4
    Right you are. Yet, the discussion on whether or not environmental issues should be taught in schools are also a vital aspect when considering which environmental theories for which there consists a general approval of and for which it does not.

    Still, as you state, the discussion in this forum should not focus on whether something should be forcibly taught or not, but rather which theories should be taught in schools if such a corriculum were to be imposed. That is the true question; what is the correct theory?
  6. Oct 31, 2007 #5

    jim mcnamara

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    AppleBite -

    Um, it's more complex than you might like.

    A international climate panel, the IPCC, issued a statement that there is a 90% chance that the warming we are seeing (the warming is pretty much accepted as real) is caused by human activity, like dumping [tex]CO_{2}[/tex] into the atmosphere.

    See this site:http://www.ipcc.ch/

    So we have a
    Part A: is there a very recent warming trend - yes. IMO.
    Part B: did humans do it (implication being humans can undo it)? less certainty, the IPCC says a 90% chance humans did it.

    And there is a more slippery Part C:
    What will happen? - the answer here is that any answer you see is at least partial speculation by experts or maybe something derived from a model. While speculation from a climate expert is absolutely better than what you & I can come up with, it is very far from established scientific fact.

    For example:
    While rising sea levels will do exactly what is described, see the policymaker's document, the extent of the possible rise (based on the assumption that things stay warm) is hard to forecast well. The IPCC provides uncertainty guidance for policymakers to allow them to get a handle on the policymaker's document contents, and assess the threats they perceive.

    The difference between a sea level rise of 6" versus 2 feet (as a contrived example), is the displacement of extra millions of people living in low-lying areas near the sea - parts of Florida, or New York City, for example. And loss of infrastructure a long with it. In theory.

    So - bottom line - it's as much political as scientific, and I think if humans caused it we are in deep doo-doo. Human governments that fix things other humans broke have a horrible track record. Humans fixing things they did not break also has a bad rep. It's a lose-lose thing IMO.
  7. Oct 31, 2007 #6
    Right you are again Mr. Mcnamara. Good work.

    The questions you've posted are exactly the theories I was refering to. There is today a general consensus on global warming, what it is and what is causing it. However, there is still debate within the community on what the results will be. There are still debates on how weather will be affected by the rising temperatures, for example, and as you state yourself about the rising sea levels. The question on whether we can predict these changes BEFORE they occur, (many of them are accelerating already) is yet to be determined.

    The question of politics is also an important aspect. Now, although we humans have a history of shooting ourselves in the foot and then jumping into a pool with sharks, the alternative of just sitting there doing nothing with the matter seems to me more terrifying than the results of a possibly-failed attempt. Would you not agree?
  8. Nov 1, 2007 #7

    jim mcnamara

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    Let's assume the climate isn't "broken", in the sense that us humans did not do much of CC, something else did.

    If we can't identify the cause with great certainty, how can we fix it? Right now, the IPCC says we have a 90% chance of being right. So, conversely, we have a 10% of applying a wrong fix. Assuming there exists a fix.

    Let's follow the 10% chance of being wrong:

    Suppose that global dimming is real. There is evidence to support the idea, but I'm not a climate scientist, so I cannot say definitively what it's status is. Anyway, suppose we clean the skies up, and let more sunshine in. And, further, suppose that our problems are due in part to insolation - solar input - our 10% chance of a wrong solution. Cleaning the skies will just make it even hotter.

    This is an absolutely horrible example, but it's the best I can do. Maybe we can fix it, or maybe our piddling will cause the next white earth phase, who knows?

    We all have a hidden assumption of cause and effect in this problem. The implication is 'removing the cause removes the effect'. But you have to be clear about the cause.
    And in climate does removing the cause reverse the problem?

    Climate is VERY complex. One approach to science is to deal with complex systems by abstracting out a few things, one at a time, and then analyzing each in turn. It just takes time. We are in so-called beta science in climatology. We need time to assemble the pieces we abstracted out an put them back into agrand model. But we don't have time to do that. If in fact we are the cause of the current problem.

    It's a quandary - a lose-lose situation as I said. Basically, I do not know more than that it is getting warmer, nothing else is all that clear to me. Did we do it? I do not know for sure. Since it is in the political arena where logic does not apply, we all will probably lose. US policy makers are more interested in keeping themselves in office than in anything else.

    I'm really old so all of this is just gonna kick future generations in the teeth. Not me, I already lost some teeth. :)
  9. Nov 22, 2007 #8
    It is not a horrible example Jim, because that is exactly what happened from 1940 - 1970. The climate was cooling, even as solar activity and GHGs were increasing because of the cooling effect of aerosols. This is known as http://en.wikipedia.org/wiki/Global_dimming" [Broken]

    Last edited by a moderator: May 3, 2017
  10. Nov 28, 2007 #9
    That is a good example Skyhunter.

    However, the sad part of the tale is where the aerosols come from of course. There has been drawn quite good links between global dimming and seismic activity in the same period of time(vulcanoes errupting all over the place, to put it bluntly), as well as human sources such as the sulfur aerosols in what you quote.
  11. Dec 3, 2007 #10


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    What concerns me is the fact that many proposed solutions do not involve removal of the suspected cause. A project to stop Global Warming has already begun, that assumes human output of CO2 is the cause, and suggests dumping tons of iron oxide into the ocean is the cure. The iron oxide will provide a rich growth medium for algea, which in turn will sequester the carbon. At least, that's the plan. I think dumping huge amounts of rusty metal into the ocean might have some effects we haven't predicted yet. so could deliberately triggering a population explosion among the microorganisms of a particular habitat.

    To make matters worse (for my own peace of mind, that is), I do not belong to the "concensus" who agree that Global Warming is even happening at all! I'm not saying it isn't, only that I'm not anywhere near convinced that it is. What if the temperature isn't going up, and we find some clever way to reduce it?

    I think there is a lot of room for questions on this issue and, in light of that fact, I don't think it should be taught in the classroom under "things we know for certain."
  12. Dec 3, 2007 #11
    I believe that the restatement of the IPCC's statement is a bit more stringent than is actually the case.

    At last years APS, the statement was read to be more along the lines of "... it is 90% likely that human activity has had a significant effect..."

    The whole report reads like that. With "likely" and "very likely" being some of the top runners along with "high confidence", "significant" etc.

    The phrases are meant to correlate with an established ranking system, I believe. With "Very likely" meaning greater than 90% and it going down from there.

    What disturbs me is the fact that the media is distorting what the scientist mean when they use the word "consensus'.
  13. Aug 22, 2008 #12
    yes it should be taught in schools. climate science is very young and whatever the cause its difficult to tell whether its possible for us to reverse it. whether temperatures are goin up or not the worlds glaciers are melting at an increased rate and with 1/3 of the worlds population depending on water from glaciers its important that, whatever the probabiity that our efforts will help, its worth a shot. if we're wrong about climate change but try to do somthing about it then a small dent in the ecconomy and a small effort by everyone is the consiquence, but if we're right and dont do anything then 3 to 4 billion peoples lives could pottentially be lost. If climate change is taught in schools as factual science more students will want to do something about it than if it was taught as pottentially happening or not taught at all so i find it difficult, given the pottential disaster that climate change could cause, that its even a debate. personaly i think that more drastic measures should be taken because just cutting back on CO2 emmisions is so unlikely to help.
  14. Aug 23, 2008 #13


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    But that's just my point; those will not be the only consequences. If we're wrong about Global Warming, and we try to correct it by reducing carbon emissions, then all we end up doing is wasting time and money and effort. But, if we're wrong about it and try to fix it through some other means (like we find some clever way to dilliberately cool the planet by increased albedo) we could trigger the next Ice Age, and billions will die.

    Ironic if the clmate change we so greatly feared did not exist, untill we caused with our attempt at a cure.
  15. Aug 24, 2008 #14


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    Who exactly is making this assumption?
  16. Aug 24, 2008 #15
    we dont need to take measures to cool the planet necessarily, just slow down the negative effects. we obviously need to cut down on emmisions for a million other reasons than global warming but thats probably not going to be enough. if anything it will just slow it down. in germany they have just built a giant screen to direct cool air over a glacier to slow its melting. solutions like this are exactly what we need. the thing is, the most badly affected countires are the ones that cant afford to help themselves.

    you are right that we should definitly not play with the global climate until we are 99.9% sure of what the effects will be. there is a lot of room for a huge disaster if we miscalculate and with the vast learning still to be done in climate science that seems too likely to risk.
  17. Aug 24, 2008 #16


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    That sounds like an incredibly stupid idea, but I couldn't say with more certainly without looking at a real report.
  18. Aug 24, 2008 #17


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    Current global warming discussions are usually more about politics than they are about science. Since public education teaches both political and scientific things it makes perfect sense to teach global warming.
  19. Aug 24, 2008 #18
    I agree 100%. The last thing we need to do is deliberately attempt to meddle with the Earths climate. Sure, years and years worth of spilling our byproducts into the atmosphere may be having an effect, but imagine what we could really screw up if we were to intentionally execute a major change in global climate.

    At this point, we know just enough to get ourselves in some deep crap.

    Myth of Consensus Explodes: APS Opens Global Warming Debate

    Scientists sign petition denying man-made global warming
  20. Aug 24, 2008 #19


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    That article was incorrect, it was the APS Forum on Physics & Society that invited a debate. At no time did the APS governing body, the APS Council, retract it's stance, but it's a start in the right direction, IMO.

    If you want interesting reading, see here.

    The release of the IPCC Fourth Assessment Report Papers: Working Group I, The Physical Science Basis of Climate Change, 2005-2007; Expert Review Comments on First-Order Draft, Chapter 1. ESPP IPCCAR4WG1, which was previously withheld from the public until they were sued for the information under the "Freedom of Information Act".

    The previously withheld report can be viewed here - http://pds.lib.harvard.edu/pds/view/7794905?n=2&imagesize=1200&jp2Res=.25 Where you can see how the IPCC "picked" the data they wished to present. Make your own judgement. I would suggest you download it since the IPCC has been "moving it" without re-directional links to let you find it. Surely it's not intentional.

    I'm afraid I don't trust the title of that as it seems too sensasionalist. I don't believe that the petiton is that they "deny" AGW, but rather they believe that there is not sufficient scientific evidence to support it.
    Last edited: Aug 24, 2008
  21. Aug 24, 2008 #20
    im not an expert by any means. i dont know much at all about climate science, im a mechanical engineer. i read about it in the news recently; all i know is it involved germany, a giant screen, cool air, an slowing glacier melting. i'd imagine you are unlikely to find funding for such a project if its a 'stupid idea'. they'd of done a whole lot of computer and scale model testing before a real world test was done so chances are, its going to work, its just a matter of how bigger difference it makes.
  22. Aug 24, 2008 #21


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    You would be surprised how many hairbrained ideas can get funding from equally hairbrained organizations. How much energy would it take to cool a glacier?

    Can you find a link to this?
  23. Aug 24, 2008 #22
    Thanks for the link Evo. I remember you mentioning it in another thread at one time, but didn't see a link. I tried searching for it with Google but couldn't find the original.

    That's pretty much what I read into it. I usually take headline statements with a grain of salt anyway. Did you by chance hear about Chris Landseas resignation from the IPCC last year? With all the talk about the IPCC being sway by political agendas, it was a little hard to find truth in it. His resignation letter definitely didn't help my opinion of them.


    Resignation Letter of Chris Landsea from IPCC
  24. Aug 24, 2008 #23
    I'd also like to see a link. The first question that pops into my mind is are they 100% certain that the glacier melting isn't being caused by a local condition rather than global?
  25. Aug 25, 2008 #24
    That's right. There are two sides to this, About the science, you could question the basic assumption of AGW that the difference between the "black body" radiation and the actual average temperature of 33 K is caused by the greenhouse effect. Advise to consult a basic meteorology textbook for that and learn about convection, hadley cells, etc and use your physical knowledge to project transfer of energy here.

    about the political-economal side, this is the wrong place to discuss it. To "follow the money" it might be interesting to google Enron Kyoto, but fasten seatbelts first.

    I intend to upload and link to the missing IPCC documents but I have to find out if that is legal first. I can mail them though.
    Last edited: Aug 25, 2008
  26. Aug 25, 2008 #25


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    This too, is incorrect. The petition signed by 31,000 scientists (the majority of whom don't have PhDs?) says the following: "There is no convincing scientific evidence that human release of carbon dioxide, methane, or other greenhouse gases is causing or will, in the foreseeable future, cause catastrophic heating of the Earth's atmosphere and disruption of the Earth's climate."

    They do not go anywhere near denying AGW. They only deny that it would be catastrophic as well as disruptive in the foreseeable future.

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