On Wed, Mar 05, 2014 at 11:01:50AM +0100, Peter Wendorff wrote: > Aren't volcanos exactly what geothermal refers to, only near or at the > surface instead of deep down in the earth?
apparently not, I can only direct you to the wikipedia article: http://en.wikipedia.org/wiki/Geothermal_%28geology%29 > IMHO geothermal refers to "using the thermal energy (aka heat) of the > earth", which of course in general is higher if you go deeper down, but > the temperature per depth is variable, and at a volcano you just get > high temperature even in low depths, but that's all. yes but it is a difference. If we can do better we should not introduce new tags only to use them incorrectly afterwards. * hot_spring would catch everything that is called hot_spring, I am still thinking about geysirs. * geothermal would not apply for many south Italian hot springs, Methana (Greece) and Yellowstone ( http://pubs.usgs.gov/fs/2005/3024/, http://en.wikipedia.org/wiki/Grand_Prismatic_Spring ) ammong others Now consider the definitions in wikipedia * temperature: ** wikipedia-de: above 20°C ("Gemäß den Begriffsbestimmungen werden in Deutschland Grundwässer als Thermalwasser bezeichnet, wenn ihre Temperatur am Austrittsort mehr als 20 °C beträgt") ** wikipedia-en: *** a spring with water temperatures above its surroundings[2] *** a natural spring with water temperature above body temperature – normally between 36.5 and 37.5 °C (97.7 and 99.5 °F)[3] *** a natural spring with warm water above body temperature[4] *** a thermal spring with water warmer than 36.7 °C (98 °F)[5][6] *** a natural spring of water greater than 21.1 °C (70 °F) (synonymous with thermal spring)[7][8][9][10] *** a natural discharge of groundwater with elevated temperatures[11] *** a type of thermal spring in which hot water is brought to the surface. The water temperature of a hot spring is usually 6.5 °C (12 °F) or more above mean air temperature.[12] Note that by this definition, "thermal spring" is not synonymous with the term "hot spring" *** a spring whose hot water is brought to the surface (synonymous with a thermal spring). The water temperature of the spring is usually 8.3 °C (15 °F) or more above the mean air temperature.[13] *** a spring with water above the core human body temperature – 36.7 °C (98 °F).[14] *** a spring with water above average ambient ground temperature,[15] a definition favored by some *** a spring with water temperatures above 50 °C (122 °F)[16] I would not want to go as far as fixing wikipedia before making a definitionin OSM So my conclusion - using the locally accepted classification is the only usable definition of hot springs. Richard _______________________________________________ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging
