cliwoc attributes

Download CLIWOC Attributes

Post on 01-Nov-2014



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  • 1. Shipping and weather dataCLIWOC ships captains logs 1662-1855A Question on Joining Look-up TablesAndrew ZolnaiCambridge UKaiz@zolnai.caImage: Royal Museum Greenwich

2. Historic Climatology Ships captains logs data from 1662 to 1855 Ships and routing details and location Weather recording of almost 120 parameters Release 1.x (2004) and Release 2.x (2007) 3. Location Metadata First added to Esri file geodatabase The complete (weather and location) dataset hasalmost 290,000 points, and is almost 250Mb database The locations were extracted into a geodatabase (70Mb), then into a compressed file geodatabase (10 Mb) Post map package for Release 2.0 layer files showing them in 25-year time-slices and for Captains Cook and de la Perouse Posted as ArcGIS Online map service Use time stamps to aggregate layers But stock server has performance issues So Filter data by nationality and decade Limits web fetches to 1000s not 100,000s 4. (Visio Pro data model reverse-engineeredfrom Dbase extracts of File Geodatabase) 5. Climate Metadata CLIWOC posted all shipboard data it had from British, Dutch, French and Spanish sources with look-up tables for each different source Merged wind force and direction data almostdoubles the number of feature classes as observed Started with Wind Force Then joined Wind Direction Finally merged Force & Direction Map package and layer template 6. (Dbase extract 8 char limit:add prefix ofCLIWOC21_Features_to all except look-upsLookup_{ }_WindDirection_) 7. (Dbase extract 8 char limit:add prefix ofCLIWOC21_Features_to all except look-upsLookup_{ }_WindForce_) 8. Wind Direction from each Maritime Agency Look-up to MergedWind Force from each Maritime Agency Look-up to Merged 9. Question Joining four lookup tables for each Nationality /Maritime Agency created redundant attributes Performing a merge in Geoprocessing collapsed theredundancies into single computable columns Why does it almost double the feature count? GIS data Visio diagrams