tag:blogger.com,1999:blog-8524070301101240472.post3585135379098290709..comments2023-09-28T08:13:11.489-07:00Comments on Only In It For The Gold: The Falsifiability QuestionMichael Tobishttp://www.blogger.com/profile/08229460438349093944noreply@blogger.comBlogger14125tag:blogger.com,1999:blog-8524070301101240472.post-31020001311748743302011-10-08T06:45:08.183-07:002011-10-08T06:45:08.183-07:00I think you are committing something of a straw ma...I think you are committing something of a straw man on this one and will endeavour to provide you with a more cogent argument against AGW concerning Falsifiability so that your refutations have more credence.<br />As Sir Karl Popper originally argued, falsification, not validation, is the criterion of a scientific theory. That is, in order for a theory to be scientific it must make risky (the more so the better) testable predictions. <br /><br />Einstein's theory of relativity is a great example of this. Eddington, in accordance with Einstein's theory of relativity predicted that during a total eclipse, some light from the sun would still be seen, as the moon would bend the light so it could be seen, even though the moon was directly between the sun and earth. In this way, he was able to test Einstein's theory of relativity, either the predicted phenomena would be observed and the theory would be strengthened by a genuine failure to falsify it, or it wouldn't be and the theory would be discarded.<br /><br />The criticism of AGW is that it does not make risky, testable predictions, so is not falsifiable. Following from my previous premise, if AGW is not falsifiable, it is not scientific.<br /><br />You claim that AGW is a consequence of a theory rather than a theory itself. I think that from this we can say that AGW isn't all that scientific then. It's like NASA trying to predict where one of their spacecraft will land, it's too applied, there are too many extraneous details for anything like a reasonable prediction.tullfroghttps://www.blogger.com/profile/05547329275129332691noreply@blogger.comtag:blogger.com,1999:blog-8524070301101240472.post-79386521567324276322009-08-23T21:04:18.414-07:002009-08-23T21:04:18.414-07:00"I thought that, without any feedbacks, a dou...<i><br />"I thought that, without any feedbacks, a doubling of CO2 would result in 1°C of global warming. The IPCC estimates that positive feedbacks will multiply this to produce around 3ºC of global warming."<br /></i><br />The figure of 3 C for a doubling of CO2 is the Charney sensitivity. It leaves out several aspects of climate because they were (or are) poorly understood or hard to simulate. These include ice sheets and the carbon cycle. Melting ice sheets reduces the planetary albedo, which in turn increases warming. Melting of ice sheets is a positive feedback not included in the 3C figure. Warming of arctic and subarctic soils melts permafrost. Melting permafrost releases CO2. Another positive feedback not in the Charney sensitivity. Warming enables beetle infestations in boreal forests, which kill trees, <a href="http://climateprogress.org/2008/04/25/nature-on-stunning-new-climate-feedback-beetle-tree-kill-releases-more-carbon-than-fires/" rel="nofollow">releasing CO2</a>. Large expanses of dead trees increase fire risk, resulting further carbon emissions. <a href="http://climateprogress.org/2009/08/17/positive-methane-feedbacks-permafrost-tundra-methane-hydrates/" rel="nofollow">More exotic positive feedbacks</a> may also be significant, and yet not in the Charney sensitivity. Please read <a href="http://www.realclimate.org/index.php/archives/2008/04/target-co2/" rel="nofollow">Real climate</a> for an in-depth discussion.llewellyhttps://www.blogger.com/profile/16001213921499191213noreply@blogger.comtag:blogger.com,1999:blog-8524070301101240472.post-30941709828651055432009-08-16T09:37:06.340-07:002009-08-16T09:37:06.340-07:00Georges,
That is essentially correct, yes. Multip...Georges,<br /><br />That is essentially correct, yes. Multiple lines of evidence converge on the net closed-loop amplification being close to 3 C. But if the earth had no water and simpler surface processes, I believe the number comes out to 1.2 C if I recall correctly. <br /><br />There is little doubt that water vapor feedback is an amplifying effect; the phenomenon is straightforward. Quantifying it is more difficult.<br /><br />Should the closed loop factor be different from 3.0 C, it will not constitute a falsification. If it turns out less than 1.5 or more than 5, it will be very surprising, and it will be an indication that something important has been missed, most likely. Some phenomenon we would have missed. It's very unlikely.<br /><br />But for the climate not to change at all under such forcing, that is essentially impossible. So when people ask what it would take to falsify, they're not asking a well-posed question.Michael Tobishttps://www.blogger.com/profile/08229460438349093944noreply@blogger.comtag:blogger.com,1999:blog-8524070301101240472.post-60311314597391805782009-08-16T08:44:08.363-07:002009-08-16T08:44:08.363-07:00Hi Michael
Sorry if I'm in the slow class her...Hi Michael<br /><br />Sorry if I'm in the slow class here.<br /><br />I thought that, without any feedbacks, a doubling of CO2 would result in 1°C of global warming. The IPCC estimates that positive feedbacks will multiply this to produce around 3ºC of global warming.<br /><br />This is crucial, because a warming of the planet by 1ºC is barely newsworthy, whereas 3ºC is a real problem.<br /><br />So what are the feedbacks? Mainly water vapor, ice-albedo & clouds. How well do we understand them? Are they all positive? Might clouds, for instance, have a mixture of positive and negative feedback effects?<br /><br />I think the 3ºC figure has a lot going for it, and is probably right. But the assumptions this figure is based on could be proved false, if the future climate diverges significantly from the IPCC predictions.georgesdelatourhttps://www.blogger.com/profile/03548858896924613970noreply@blogger.comtag:blogger.com,1999:blog-8524070301101240472.post-30273581289176887312009-07-29T10:17:55.714-07:002009-07-29T10:17:55.714-07:00Kate, yes, thanks.
You should blame Fourier, not ...Kate, yes, thanks.<br /><br />You should blame Fourier, not Arrhenius, for the fundamental physics. Arrhenius was first to work out the arithmetic, but the principles go back to Fourier around 1820.<br /><br />See http://www.aip.org/history/climate/simple.htm<br /><br />And of course, if we don't understand radiative physics, we also don't have any satellite measurements of the earth, or really any idea at all about planets and stars. That is a lot of apparently successful work to contemplate throwing away!Michael Tobishttps://www.blogger.com/profile/08229460438349093944noreply@blogger.comtag:blogger.com,1999:blog-8524070301101240472.post-32762431521949472072009-07-29T10:06:14.383-07:002009-07-29T10:06:14.383-07:00Very nice post, it sort of clarified some topics w...Very nice post, it sort of clarified some topics which were swirling around in my head, the "how could it not change climate?" idea is very true. The burden of proof is really on the skeptics to explain how we couldn't change the climate.<br /><br />If some new explanation came up which proved Arrhenius wrong (and really proved, not Watts-says-so proved), something which turned our understanding of radiative physics on its head, then I would accept that we weren't changing the climate. But until then, the prospect is too illogical.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-8524070301101240472.post-86303602376440825612008-12-18T14:25:00.000-08:002008-12-18T14:25:00.000-08:00I don't see the word 'ridiculous' anywhere on this...I don't see the word 'ridiculous' anywhere on this posting or the comments to it, and I doubt I would have used in this context, so I don't see why I should feel obligated to defend or clarify anything.<BR/><BR/>To answer your question, CO2 is not the only influence on climate. <BR/><BR/>It appears to lag temperature in the onset of the last glacial cycle especially in the southern hemisphere. The relationship between geochemistry and CO2 on that time scale in nature is not a solved problem, but it is pretty much conventional wisdom that the deglacitations are kicked off by solar forcing at the edge of the expanded ice sheets and not by CO2.<BR/><BR/>If CO2 has no great effect, explaining the 100,000 year cycle becomes dramatically more difficult, not less so.<BR/><BR/>That said, the local warming before the onset of northern hemisphere deglaciation in Antarctica is indeed peculiar and not well explained, but then again neither are most of the other bumps and wiggles in the record. It may be coincidental.<BR/><BR/>Nobody has made a significant scientific case about this event, as far as I know. The denialists have picked it as one of their favorite refutations but it really doesn't refute much of anything. <BR/><BR/>This peculiarity in the Antarctic ice cores just shows that CO2 is not the only influence. It doesn't show that CO2 has no influence. Of course, it can't do that, because reality has the highly useful property of being consistent.Michael Tobishttps://www.blogger.com/profile/08229460438349093944noreply@blogger.comtag:blogger.com,1999:blog-8524070301101240472.post-61275074627170121962008-12-18T14:09:00.000-08:002008-12-18T14:09:00.000-08:00HiWould you explain, please, why "CO2 lags tempera...Hi<BR/>Would you explain, please, why "CO2 lags temperature " is a "ridiculous" argument. At least it means that historically CO2 did not cause increases in temperatureAnonymousnoreply@blogger.comtag:blogger.com,1999:blog-8524070301101240472.post-89231852487490970442008-09-15T05:52:00.000-07:002008-09-15T05:52:00.000-07:00This comment has been removed by the author.Ianhttps://www.blogger.com/profile/01466343070140208641noreply@blogger.comtag:blogger.com,1999:blog-8524070301101240472.post-85799557005737667332008-07-26T12:06:00.000-07:002008-07-26T12:06:00.000-07:00Some discussion about this post here on an anti-su...Some discussion about this post here on an anti-superstition site: http://forums.randi.org/showthread.php?p=3892650<BR/><BR/>more or less as an indirect consequence of the word "skeptic" being appropriated by the delay squad.Michael Tobishttps://www.blogger.com/profile/08229460438349093944noreply@blogger.comtag:blogger.com,1999:blog-8524070301101240472.post-50081018292129568062008-05-08T19:53:00.000-07:002008-05-08T19:53:00.000-07:00Good post. I'm going to add this blog to my blogr...Good post. I'm going to add this blog to my blogroll. <BR/><BR/>From basic physical principles, AGW just follows from physics, such as radiative transfer, fluid dynamics, etc. I think that from a purely rigorous view, a falsification would require something absurd like showing that CO2 does not absorb infrared radiation, but since that's just not going to happen, AGW does carry some baggage to it along with just that...such as<BR/><BR/>- climate sensitivity is not negligible (I'll say greater than 2 C). Societal impacts will also be non-negligible<BR/><BR/>- Water Vapor increases with temperature to increase the absolute humidity but keep relative humidty pretty constant, and is thus a positive feedback to the GHG-induced warming.<BR/><BR/>- Expectations in a warmer climate, such as polar amplification and expectations of AGW, such as stratospheric cooling will be borne out<BR/><BR/>There's not much to convince me that any of this is wrong. If "skeptics" (not exactly the best word) want to make an argument, then they'll need to stop the nonsensical arguments such as "CO2 lags temperature" and "but it cooled in mid-century!" and boasting their arguments on fraudulent foundations of OISM, Inhofe's gang, etc. I would say that an appropriate rebuttal to AGW would also include something coherent from "the other side."Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-8524070301101240472.post-64275518695517378802008-05-05T14:35:00.000-07:002008-05-05T14:35:00.000-07:00Thanks!KCET owns everything I write over there, so...Thanks!<BR/><BR/>KCET owns everything I write over there, so I can't cross-post.<BR/><BR/>Also this really isn't the most accessible thing I could write on the subject. Maybe I'll try writing something similar for them, though.Michael Tobishttps://www.blogger.com/profile/08229460438349093944noreply@blogger.comtag:blogger.com,1999:blog-8524070301101240472.post-55035337377686135642008-05-04T19:19:00.000-07:002008-05-04T19:19:00.000-07:00Great post. You articulated a lot of thoughts runn...Great post. You articulated a lot of thoughts running around in my head regarding the 'falsification' meme clearly and concisely. If this isn't cross-posted at your Wired blog, it should be.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-8524070301101240472.post-53536490158428254372008-05-04T04:38:00.000-07:002008-05-04T04:38:00.000-07:00This comment has been removed by the author.apa tycka, apa skrivahttps://www.blogger.com/profile/11386141912731889101noreply@blogger.com