Wednesday 30 January 2019

Dynamic maps - finis

[Update 2:  this Story Map chronicles the 15 years of this on-again-off-again  work
Update 1: new Spillhaus projection is too cool for ocean data, see this on YouTube]

My last post on dynamic maps and its preceding project recap five years ago outlined how I used ¼M point free-to-use dataset on global historic shipping and climate data. This is the original video of ships'  locations produced a decade ago on Esri ArcMap:

The latest ArcGIS Pro update added a new projection, more akin to that used by National Geographic world maps: it  avoids the polar distortion you see above, which you will also see on Google Maps.
This has been addressed by Google Maps desktop that switch to globe view when zoomed out sufficiently. And I addressed this with polar Antarctic then Arctic  map exercises in QGIS and ArcGIS.
This Equal Earth projection was recently created by commercial, government and academic trio. They offer a global map view that's more pleasing than alternatives recently sought against a de-facto web map standard. It was rapidly made available to all other platforms from desktop to web.

Here is the global ships' location video for the 1745-1855 interval. It is colour-coded by traditional red (British), blue (French), orange (Dutch), yellow (Spanish) and grey (all others in small numbers). Note: CLIWOC did not include Portuguese data, a pity given their exploration record at that time.

Here are the global wind speed & direction video for the same time interval. Beaufort wind force scale is in rainbow colours, from smaller blue atop for lower wind force, to larger red  at bottom for stronger wind force - this ordering addressed the considerable overlap. Note: there are less data points at times; the painstaking recording twice a day of up to 120 parameters for the captains' ships logs had some shortcoming discussed in para. 3 of this map blog.

The improvement of the map proportions is complemented by Esri's Living Atlas oceans.
Harel Dan said in Geohipster: "There’s no reason not to share your work and ideas with the geo community", so please help yourself:
  • My projects are CC BY-SA 3.0 and posted online as explained in my earlier blogpost, which shall be updated  
  • This project will also be posted on Dropbox; if you're not on Esri, then low-fee ArcGIS Personal Use accesses them
  • Otherwise watch the next blogpost for brand new geopackaging alternatives in, say, QGIS to be also posted on Dropbox

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