Talk:Coastline paradox

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[edit] Removed note

Actually it does mean that the coastline is of infinite length... or at least that successive approximations diverge. As you measure on smaller and smaller scales, the perturbations increase in magnitude, instead of vanishing. In a moment I'll be removing the section at the end of the article that confuses the whole issue, and adding a citation from Mandelbrot's "The Fractal Geometry of Nature". Andrew Rodland 06:07, 16 June 2007 (UTC)

For clarity, this is my comment on a section of the article I removed and rewrite, and not a note which was removed. I apologize for the poor heading but I'm not going to change it now. Andrew Rodland 06:27, 16 June 2007 (UTC)

It seems to me that the notion of coastlines being fractals and of infinite length and so on confuses the actual nature of coastlines with representations on them on maps. Even then it is not obvious to me that mapped coastlines are necessarily fractals. Even in the most fjordy, rock-ridden places there are tides, waves, mudflats, estuaries, marshes, etc. The coast "line" changes with tides and waves, and is ill-defined in estuaries, marshes, mudflats, and so on. In short, coastlines are only two-dimensional lines in the abstract, and dependent upon human-defined boundaries (eg, just where is the exact line between land and sea in Louisiana?). The fractal nature is obvious when looking at maps -- especially at larger, zoomed-out scales -- but in the real world it is not so simple. I realize there are sources that claim coastlines are fractals and infinite in length, and I have yet to find a source that offers a more realistic perspective (of course I haven't really looked). Still I can't help but comment on the topic. It seems obvious -- just try using an inch-long ruler to measure the "coastline" on a broad stretch of beach where the waves wash 50 feet in and out, while the tide is turning. Wouldn't the main problem be not that coastlines are fractals, but that they are subject to waves, tides, and are not "lines" at all? Pfly (talk) 06:19, 17 April 2008 (UTC)