With the best will in the world, what use is a contour plot operationally, when a simple graphic will in fact do, and be much easier to read? The only thing the contours and colours add is prettyness for those who don't need it, detail for those who need it! If you can't fly in concentrations of ash above 400micrograms, then thats all you need to know! People always want flashy pictures.... :P
What you need to remember though, and what has been mentioned numerous times, is that meteorology is an inexact science (its not bad science in any way, but the atmosphere is a complex beastie!) I don't know what those Norwegian charts represent - I don't read Norwegian and I can't see anything other than a single image! However the dispersal pattern of whatever it represents doesn't look too dissimilar to those on the Met Office VAAC charts. Some agencies will produce much more "optimistic" charts, and others much more "pessimistic". Just because one chart shows you what you want to see now, doesn't mean it will show you what you want to see later - you have to accept that the atmosphere changes dynamically, and that each model run will be different.
and if it helps, the meteorological community do talk to each other, and are highly collaborative.
and finally, every Met organisation in the world is most likely capable of producing pretty contoured output like the Norwegian Met Office.
Last edited by Postman Plod; 26th May 2011 at 09:21.