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Talk:Counterexamples to an Old Earth (view source)
Revision as of 14:35, December 22, 2011
, 14:35, December 22, 2011I plan to answer Aschlafly's question...
Archive index also created.
Archive index also created.
[[User:JonM|JonM]] 00:49, 22 December 2011 (EST)
[[User:JonM|JonM]] 00:49, 22 December 2011 (EST)
== Major earthquakes are doubling every 40 years? ==
This claim should come out because it's false. Proof that it's false can be found here:[http://www.ngdc.noaa.gov/nndc/struts/form?t=101650&s=1&d=1]. For example between 1900 and 1909 there were 120 major earthquakes; between 2000 and 2009 there were 99. 100 years and no doubling - in fact, a 20% decrease. It doesn't help our case to make arguments that can be demonstrated to be false in 5 minutes. --[[User:MandyC|MandyC]] 18:57, 23 October 2011 (EDT)
:That database appears to depend in part on the amount of property damage, which would distort the results beyond recognition.
:Large earthquakes increased by 20% over the past decade, which fits almost perfectly the estimate of doubling every 40 years.--[[User:Aschlafly|Andy Schlafly]] 19:03, 23 October 2011 (EDT)
::They've doubled every 40 years if you only go back 40 years. If you go back 110 years they've stayed constant or decreased slightly. That database includes ALL major earthquakes; property damage is just one of the criteria you can search on. --[[User:MandyC|MandyC]] 19:10, 23 October 2011 (EDT)
::Actually I'm wrong. They've increased by 80% in the last 30 years. They've only increased by 20% in the last 40 years. They've stayed constant over the last 110 years. Numbers fluctuate but is always about 100, +/-30, per decade. There is NO INCREASE in major earthquakes and we shouldn't be claiming there is, because we can easily be proven wrong. --[[User:MandyC|MandyC]] 19:14, 23 October 2011 (EDT)
::: The table in the cited reference shows an increase factor of 1.5-4 every 38 years, and recent trends confirm a substantial increase over the past few decades. The statement seems well-supported by the table and recent data.--[[User:Aschlafly|Andy Schlafly]] 19:56, 23 October 2011 (EDT)
::::Yes, but the cited reference contradicts its own cited reference, which is the USGS earthquake data (found in the NOAA database.) There has been a substantial increase per decade since 1980, a MINOR increase per decade since 1970 and no increase whatsoever since 1900. The 1970s had exceptionally low earthquake activity and the increase since then is a statistical phenomena known as regression to the mean; it's the same numbers trick that makes it appear that speed cameras placed at accident blackspots reduce accidents. Anyone can cherry-pick figures to prove anything, but the long-term increase simply isn't there. There were more severe earthquakes between 1900 and 1910 than between 2000 and 2010. --[[User:MandyC|MandyC]] 20:13, 23 October 2011 (EDT)
Today the study ''[http://www.pnas.org/content/early/2011/12/12/1118525109.abstract Global risk of big earthquakes has not recently increased]'' was published: the authors show that the earthquakes of the last hundred years fit well into the model of a homogeneous Poisson process, i.e., there is no increase of the number of big quakes. ''Together these facts suggest that the global risk of large earthquakes is no higher today than it has been in the past. '' [[User:AugustO|AugustO]] 17:50, 20 December 2011 (EST)
:AugustO pulls out the heavy artillery: The Poisson distribution! The material on multiple regression and the Poisson distribution were my favorite parts of the last statistics course I took. :) [[User:Conservative|Conservative]] 22:08, 20 December 2011 (EST)
::AugustO, the article states, "The global rate of M≥8 earthquakes has been at a record high roughly since 2004." Its conclusion that earthquakes have not been increasing based on its view that "no plausible physical mechanism predicts real changes in the underlying global rate of large events." They need to spend more time studying and learning from [[Counterexamples to an Old Earth]]. Of course there is a plausible mechanism: increased disorder affects the Earth just as it affects everything else.--[[User:Aschlafly|Andy Schlafly]] 00:08, 21 December 2011 (EST)
:::Mr. Schlafly (Andy? What's the etiquette when user name = real name?), respectfully, I believe your short quotations from the abstract of the paper distort the context in which they were made. Here's the surrounding context:
{{cquote|We examine the timing of large (magnitude M ≥ 7) earthquakes from 1900 to the present, after removing local clustering related to aftershocks '''The global rate of M ≥ 8 earthquakes has been at a record high roughly since 2004''', but rates have been almost as high before, and the rate of smaller earthquakes is close to its historical average. Some features of the global catalog are improbable in retrospect, but so are some features of most random sequences—if the features are selected after looking at the data. For a variety of magnitude cutoffs and three statistical tests, the global catalog, with local clusters removed, is not distinguishable from a homogeneous Poisson process. Moreover, '''no plausible physical mechanism predicts real changes in the underlying global rate of large events.''' Together these facts suggest that the global risk of large earthquakes is no higher today than it has been in the past.}}
:::(your quotations emphasized). I believe their point is that it isn't enough to simply note that there have been more large earthquakes now than previously. In any random sequence there will always be some strange results, but we can't look at those anomalies in isolation. For example, if we flip a coin a thousand times and it's overall about 50-50, but the last 10 flips are all heads, we shouldn't immediately assume that the coin has recently become biased. Instead, we should consider the likelihood that chance alone could generate such a streak. I don't know enough about the math to evaluate their conclusion, but I think their premise is sound and I think you've mischaracterized it.--[[User:JustinD|JustinD]] 01:04, 21 December 2011 (EST)
:@Conservative: just take another course on statistics and you may find out the distinction between the Poisson distribution and a Poisson process.
:@Aschlafly: ''increased disorder affects the Earth just as it affects everything else'' that's not a ''plausible physical mechanism'', that's a philosophical statement.
:[[User:AugustO|AugustO]] 02:08, 21 December 2011 (EST)
::Entropy is physics, not philosophy. If you don't think increased disorder affects the [[Earth]], then please explain your view on whether [[perpetual motion machines]] are possible.--[[User:Aschlafly|Andy Schlafly]] 23:30, 21 December 2011 (EST)
:::It also relates to the second law of Thermodynamics, which states that Entropy in a system must always increase. [[User:NickP|NickP]] 00:17, 22 December 2011 (EST)