<[EMAIL PROTECTED]> wrote in message news:<[EMAIL PROTECTED]>... > > > For consequences like that, I'd hope a one in 10,000 chance would do it! > > I think meteorite strikes and what, or rather how little, we do about
(btw, I think in this example, the odds are 1 in millions and we are taking actions.) > I think meteorite strikes and what, or rather how little, we do about > them is an indication that even for extinction we do take account of > probability. As we should, that's what I mean. But so far I have yet to see any discussion of what probablity of really catastrophic climate change it would take to justify some kind of tangible sacrifice. So far the discussions seem to encompass mostly arguments about whether or not it is worth "a single american job" and the underlying assumption that 100% certainty of anthropogenic causes is required before any change in policy is justified. I don't think I made my point clear, I hope that helps. I think the IPCC is too complacent a vehicle to fully frame the important questions. I think Michael Tobis has made this point frequently, but it is not only rational, but essential, to provide insight into the possibilities, even if the uncertainties are huge, of really disasterous occurences. eg. if the science can not *rule out* with greater than, say 99% (higher? lower?) certainty the release of huge quantities of ocean sediment methane then that should be on the table, front and center. I recall thinking when James et al's paper on climate sensitivity came out where they find 95% certainty of sensitivity less than 4.5oC that that is simply not an acceptable risk. 5% chance of 4.5oC warming before 2100 is *not* good news! And this does not even consider (as far as actual temperature projections go) carbon feedbacks from permafrost and oceans. Can science tell us that this *will not* happen with 99% certainty? > > > You should just accept the straightforward explanation, the vast > > > majority of the population is not convinced that climate change is > > > gonna wipe us out. > > > > You keep stating this in a way that implies it means it must be the truth. > > I don't think there is any good reason to make that leap, in this issue or > > any others! > > There is very little we can state as being true with 100% probability. > I think there's a spectrum of possibilities/opinions as to how bad > climate change can/will be, and I think that Alastair's take on this > goes well beyond the IPCC consensus or most climate scientists' own > opinions. I'm 0 for 2, here, let me clarify. I meant to say that you have several times quoted the public's expectations of future risks as if that were a gauge of the reality. It does not matter to the reality of the situation if the public by and large is or is not worried. Yes, Alastair's take is well beyond the consensus. It is beyond my personal assessment. But I can not say what he fears is *impossible*. And as soon an outcome is (practically) not impossible it should be on the table, it should be assessed as to how likely or unlikely it is and it should be in the equation used when deciding what to do. Scientists would waste 99% of their time if they focused always on extreme improbabilities, when you want to find something, look in the most likely place. So if sound science says there is only a 1% chance that an ice sheet could behave in a particular way, then they quite rightly develope theories that are based on something 99% likely to be right. But risk assessment has to look at the improbable outcomes as well, especially if they have severly negative outcomes. > You are not nearly as pessimistic as Alastair, but still on the > pessimistic side of general opinion on climate change and peak oil. Probably. But again, general opinion is irrelevant, reality is not democratcally determined! I am mostly very pessimistic about the future IF nothing is done to directly address the problems. I have not decided what I think will actually happen. > The IPCC does not predict the end of civilisation, and their > assumptions on petroleum availability rather differ from those of a > number of prominent petroleum geologists associated with "peak oil". Yes, peak oil can change everything. It could be in good (for CO2 emissions) ways, or bad ways. I think this is kind of like trying to predict the path of not one, but two hurricanes that are about to collide. > http://www.oilcrisis.com/laherrere/EGUVienna2006.pdf > > Have a look a page 10 of Laherrere's paper, where his projection of > natural gas supply in the 21st century is compared to IPCC scenarios. > > The IPCC chapter on scenarios includes a discussion as to why they > chose those particular scenarios. They excluded massive technological > change, as in such a future climate change wouldn't matter, and > likewise excluded apocalyptic WWIII nuclear destruction type scenarios, > arguing that likewise the world would be worrying about other things. > > But, be that as it may, I think the scenarios amount to an argument > that climate change and business as usual are quite compatible (in the > basic sense that climate change won't shut the world economy down / > bring about the end of world civilisation). I don't think the scenarios incorporate the effects of the climate change they go along with, do they? ie I don't think you can look at the A1F1 scenario and say "see, een the IPCC says economic growth will be good with a 5oC temperature change by 2100". Is that what you are saying? Coby --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups Global Change ("globalchange") newsgroup. 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