Image talk:Recent Sea Level Rise.png

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I am not entirely happy with the coloration of the individual records. I think it is very important to show them, to demonstrate that sea level rise is not a matter of cherry picking records, as some sceptics have claimed, but I also am not sure what is the best way to present them. If people have suggestions, I am glad to hear them. Dragons flight 23:26, May 28, 2005 (UTC)

[edit] TOPEX/Poseideon

(William M. Connolley 10:44, 29 May 2005 (UTC)) Nice picture. Thank you. Is there any scope for ading in the satellite derived trends?

[edit] Selection criteria

I suppose this would count as "original research" or somesuch, but Donald's criteria state that sites should "Not be located at collisional plate boundaries" yet this is not the case for several of the 24 (23?) sites used:

• The four New Zealand sites are all located on or quite close to just such a boundary, and indeed all are subject to significant degrees of seismic activity--Wellington in particular is extremely active, sometimes violently so, for example in 1855 it had a Richter 8.2 earthquake which caused 3 metres of uplift! Wellington was not used for the chart but the other 3 also are fairly seismic.
• Italy (2 sites) is near a (slow) collisional zone and has moderate seismic and volcanic activity, and Trieste at least is known to be subsiding;
• California (four sites) is on a transform boundary, but one which is seismically very active. Being a transform boundary its frequent earthquakes mainly produce horizontal displacements but vertical displacements of up to 20 cm, quite close to some of these sites, have occurred many times within the observational period;
• Hawaii is not a collisional zone but is an active volcanic hotspot! Oahu (on which Honolulu is found) has no active volcanoes but is subject to occasional moderate earthquakes, about 3 quakes of greater than Richter 6 per century. These are mainly caused by the isostastic load of the massive volcanic shield and do involve vertical displacements.
• Canary islands are another hotspot like Hawaii, and are also actively volcanic! Tenerife's volcano has not erupted since the fifteenth century but nearby islands have erupted as recently as 1971, and Tenerife is subject to earthquakes.
• The three Florida sites are not subject to seismic or volcanic activity but do not "Show reasonable agreement at low frequencies with nearby guages sampling the same water mass", in fact all of them are subsiding but at different rates.

In short about 15 of the sites do not meet the stated selection criteria, and quite a few of them are in fact the antithesis of "stable". -- Securiger 16:46, 6 September 2005 (UTC)