Web maps on steroids

The last 6 blog posts over the last 3 months chronicled the use of dynamic maps using time attribute - years for historic ship tracks and wind data from same 150-350 yrs ago - not to animate maps but to filter them by decade and manage data fetches on ArcGIS Online. A parallel series of posts showed mega data sets on Amazon Web Services, as Mapcentia assured me postGIS handled giga datasets...

On joining and merging historic multi-lingual geodata

Earlier posts chronicled the history even the beauty of historic shipping and climate data from CLIWOC. British, Dutch, French and Spanish maritime agencies transferred paper logs to digital records. In doing so look-up tables allowed to convert multi-lingual records into quantifiable attributes. Something odd (to me) happened in the process of mapping these: over 1/4M records doubled to almost 1/2M when look-ups were joined and then wind and direction tables merged to create maps symbolised by wind force and orientation.