Seeing beneath Stonehenge: Data Mining Under-The-Earth?

With the successively launch of the KMZ, knowing that the data is “free”, being used and hopefully enjoyed in Google Earth has made me reminisce about my time on the Project ,and the last few weeks before launch as I worked feverishly editing KML code, checking Sketchup model imports and re-positioning Gigapan panoramas so they hugged the ground again.

What stays with me is how easy it was to bring in anything we had created using the Google suite of products. Sometimes there were glitches, but there was always a forum or blog post. Someone who’d encountered the bug, solved it, or had a workaround we could adapt and use. We rarely had to turn to our Google Liaison.

Most of our problems came from exporting GIS layers into Google Earth, and only then because of the difficulties of changing Map Projections. The normal tools for this work well, but we needed our British Grid data to map exactly into the Google globe “real location”, rather than within a few meters. We had resigned ourselves to a complicated series of imports, map proofing and educated adjustments.

Luckily, we had our Eureka moment.  My colleague Harry Manley was showing me Google Earth’s historical Aerial imagery.  I knew one Aerial photography flight had just happened to catch some of our trenches in 2005 being excavated, perhaps it was in Google Earth’s historical Aerial Imagery? Harry moved the slider to 2005. There were the trenches.

We could then adjust our transformation so that our trench outlines fit exactly, use the same formula for other applicable data and produce similar work-flows for the rest of our material. If we were doing it now, the “on the fly” re-projection in open-source GIS programs like Qgis is actually pretty amazing, as is it’s KMl export.

Google’s  brought GI and GIS map data to everyone (in fact they’ve made it ubiquitous, recently celebrating 1 billion downloads in September). Anyone can now create, edit and share the geography that interests them, from our Stonehenge Landscape data to Chinese Military Installations.


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